Add the app

.gitignore

@@ -0,0 +1,78 @@
+.DS_Store
+MyPlayground.playground/
+
+### Swift ###
+# Xcode
+#
+# gitignore contributors: remember to update Global/Xcode.gitignore, Objective-C.gitignore & Swift.gitignore
+
+## Build generated
+build/
+DerivedData/
+
+## Various settings
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata/
+
+## Other
+*.moved-aside
+*.xccheckout
+*.xcscmblueprint
+
+## Obj-C/Swift specific
+*.hmap
+*.ipa
+*.dSYM.zip
+*.dSYM
+
+## Playgrounds
+timeline.xctimeline
+playground.xcworkspace
+
+# Swift Package Manager
+#
+# Add this line if you want to avoid checking in source code from Swift Package Manager dependencies.
+# Packages/
+# Package.pins
+.build/
+
+# CocoaPods - Refactored to standalone file
+
+# Carthage - Refactored to standalone file
+
+# fastlane
+#
+# It is recommended to not store the screenshots in the git repo. Instead, use fastlane to re-generate the
+# screenshots whenever they are needed.
+# For more information about the recommended setup visit:
+# https://docs.fastlane.tools/best-practices/source-control/#source-control
+
+fastlane/report.xml
+fastlane/Preview.html
+fastlane/screenshots
+fastlane/test_output
+
+### Xcode ###
+# Xcode
+#
+# gitignore contributors: remember to update Global/Xcode.gitignore, Objective-C.gitignore & Swift.gitignore
+
+## Build generated
+
+## Various settings
+
+## Other
+
+### Xcode Patch ###
+*.xcodeproj/*
+!*.xcodeproj/project.pbxproj
+!*.xcodeproj/xcshareddata/
+!*.xcworkspace/contents.xcworkspacedata
+/*.gcno

OTP.xcodeproj/project.pbxproj

@@ -7,23 +7,119 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		D60E9D6E26D1998B009A4537 /* OTPGeneratorTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D60E9D6D26D1998B009A4537 /* OTPGeneratorTests.swift */; };
+		D60E9D7226D1A863009A4537 /* KeyView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D60E9D7126D1A863009A4537 /* KeyView.swift */; };
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+		D60E9D7726D1B160009A4537 /* CodeScanner in Frameworks */ = {isa = PBXBuildFile; productRef = D60E9D7626D1B160009A4537 /* CodeScanner */; };
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-		D61479DB26D0AF1C00710B79 /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61479DA26D0AF1C00710B79 /* ViewController.swift */; };
-		D61479DE26D0AF1C00710B79 /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = D61479DC26D0AF1C00710B79 /* Main.storyboard */; };
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 		D61479E326D0AF1E00710B79 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = D61479E126D0AF1E00710B79 /* LaunchScreen.storyboard */; };
+		D61479EB26D13DEF00710B79 /* AppView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61479EA26D13DEF00710B79 /* AppView.swift */; };
+		D61479F526D141F700710B79 /* OTPKit.docc in Sources */ = {isa = PBXBuildFile; fileRef = D61479F426D141F700710B79 /* OTPKit.docc */; };
+		D61479FB26D141F800710B79 /* OTPKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = D61479F126D141F700710B79 /* OTPKit.framework */; };
+		D6147A0226D141F800710B79 /* OTPKitTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A0126D141F800710B79 /* OTPKitTests.swift */; };
+		D6147A0326D141F800710B79 /* OTPKit.h in Headers */ = {isa = PBXBuildFile; fileRef = D61479F326D141F700710B79 /* OTPKit.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		D6147A0626D141F800710B79 /* OTPKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = D61479F126D141F700710B79 /* OTPKit.framework */; };
+		D6147A0726D141F800710B79 /* OTPKit.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = D61479F126D141F700710B79 /* OTPKit.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
+		D6147A1026D1421900710B79 /* TOTPKey.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A0F26D1421900710B79 /* TOTPKey.swift */; };
+		D6147A1326D1446E00710B79 /* Base32.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A1226D1446E00710B79 /* Base32.swift */; };
+		D6147A1726D147B400710B79 /* TOTPKeyTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A1626D147B400710B79 /* TOTPKeyTests.swift */; };
+		D6147A1926D14AAB00710B79 /* OTPGenerator.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A1826D14AAB00710B79 /* OTPGenerator.swift */; };
+		D6147A1B26D14ADF00710B79 /* OTPKey.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A1A26D14ADF00710B79 /* OTPKey.swift */; };
+		D6147A1D26D14B5F00710B79 /* OTPAlgorithm.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A1C26D14B5F00710B79 /* OTPAlgorithm.swift */; };
+		D6147A1F26D14BA000710B79 /* TOTPCode.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6147A1E26D14BA000710B79 /* TOTPCode.swift */; };
+		D68B3DA026D2937000CB35A2 /* AddURLForm.swift in Sources */ = {isa = PBXBuildFile; fileRef = D68B3D9F26D2937000CB35A2 /* AddURLForm.swift */; };
+		D68B3DA226D293BE00CB35A2 /* DismissAction.swift in Sources */ = {isa = PBXBuildFile; fileRef = D68B3DA126D293BE00CB35A2 /* DismissAction.swift */; };
+		D6A2BCAE26D29601004DC4E3 /* EditedKey.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BCAD26D29601004DC4E3 /* EditedKey.swift */; };
+		D6A2BCB026D313E7004DC4E3 /* AddQRView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BCAF26D313E7004DC4E3 /* AddQRView.swift */; };
+		D6A2BCCC26D3E670004DC4E3 /* PreferencesView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BCCB26D3E670004DC4E3 /* PreferencesView.swift */; };
+		D6A2BCD026D3E888004DC4E3 /* BackupDocument.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BCCF26D3E888004DC4E3 /* BackupDocument.swift */; };
+		D6A2BCEC26D3F7F9004DC4E3 /* QRCodeView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BCEB26D3F7F9004DC4E3 /* QRCodeView.swift */; };
+		D6A2BD0826D449FA004DC4E3 /* KeyData.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BD0726D449FA004DC4E3 /* KeyData.swift */; };
+		D6A2BD0A26D44AC3004DC4E3 /* KeyStore.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BD0926D44AC3004DC4E3 /* KeyStore.swift */; };
+		D6A2BD0C26D5332B004DC4E3 /* FolderView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BD0B26D5332B004DC4E3 /* FolderView.swift */; };
+		D6A2BD1026D533EB004DC4E3 /* FoldersSection.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BD0F26D533EB004DC4E3 /* FoldersSection.swift */; };
+		D6A2BD1226D56C70004DC4E3 /* KeysSection.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BD1126D56C70004DC4E3 /* KeysSection.swift */; };
+		D6A2BD1426D5707F004DC4E3 /* FolderRow.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6A2BD1326D5707F004DC4E3 /* FolderRow.swift */; };
 /* End PBXBuildFile section */
 
+/* Begin PBXContainerItemProxy section */
+		D61479FC26D141F800710B79 /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = D61479CB26D0AF1C00710B79 /* Project object */;
+			proxyType = 1;
+			remoteGlobalIDString = D61479F026D141F700710B79;
+			remoteInfo = OTPKit;
+		};
+		D61479FE26D141F800710B79 /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = D61479CB26D0AF1C00710B79 /* Project object */;
+			proxyType = 1;
+			remoteGlobalIDString = D61479D226D0AF1C00710B79;
+			remoteInfo = OTP;
+		};
+		D6147A0426D141F800710B79 /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = D61479CB26D0AF1C00710B79 /* Project object */;
+			proxyType = 1;
+			remoteGlobalIDString = D61479F026D141F700710B79;
+			remoteInfo = OTPKit;
+		};
+/* End PBXContainerItemProxy section */
+
+/* Begin PBXCopyFilesBuildPhase section */
+		D6147A0B26D141F800710B79 /* Embed Frameworks */ = {
+			isa = PBXCopyFilesBuildPhase;
+			buildActionMask = 2147483647;
+			dstPath = "";
+			dstSubfolderSpec = 10;
+			files = (
+				D6147A0726D141F800710B79 /* OTPKit.framework in Embed Frameworks */,
+			);
+			name = "Embed Frameworks";
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXCopyFilesBuildPhase section */
+
 /* Begin PBXFileReference section */
+		D60E9D6D26D1998B009A4537 /* OTPGeneratorTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OTPGeneratorTests.swift; sourceTree = "<group>"; };
+		D60E9D7126D1A863009A4537 /* KeyView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyView.swift; sourceTree = "<group>"; };
+		D60E9D7326D1ABF9009A4537 /* CircularProgressView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CircularProgressView.swift; sourceTree = "<group>"; };
+		D60E9D7926D1E985009A4537 /* EditKeyForm.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EditKeyForm.swift; sourceTree = "<group>"; };
 		D61479D326D0AF1C00710B79 /* OTP.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = OTP.app; sourceTree = BUILT_PRODUCTS_DIR; };
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 		D61479D826D0AF1C00710B79 /* SceneDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SceneDelegate.swift; sourceTree = "<group>"; };
-		D61479DA26D0AF1C00710B79 /* ViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ViewController.swift; sourceTree = "<group>"; };
-		D61479DD26D0AF1C00710B79 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/Main.storyboard; sourceTree = "<group>"; };
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 		D61479E426D0AF1E00710B79 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
+		D61479EA26D13DEF00710B79 /* AppView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppView.swift; sourceTree = "<group>"; };
+		D61479F126D141F700710B79 /* OTPKit.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = OTPKit.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		D61479F326D141F700710B79 /* OTPKit.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = OTPKit.h; sourceTree = "<group>"; };
+		D61479F426D141F700710B79 /* OTPKit.docc */ = {isa = PBXFileReference; lastKnownFileType = folder.documentationcatalog; path = OTPKit.docc; sourceTree = "<group>"; };
+		D61479FA26D141F800710B79 /* OTPKitTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = OTPKitTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
+		D6147A0126D141F800710B79 /* OTPKitTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OTPKitTests.swift; sourceTree = "<group>"; };
+		D6147A0F26D1421900710B79 /* TOTPKey.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TOTPKey.swift; sourceTree = "<group>"; };
+		D6147A1226D1446E00710B79 /* Base32.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Base32.swift; sourceTree = "<group>"; };
+		D6147A1626D147B400710B79 /* TOTPKeyTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TOTPKeyTests.swift; sourceTree = "<group>"; };
+		D6147A1826D14AAB00710B79 /* OTPGenerator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OTPGenerator.swift; sourceTree = "<group>"; };
+		D6147A1A26D14ADF00710B79 /* OTPKey.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OTPKey.swift; sourceTree = "<group>"; };
+		D6147A1C26D14B5F00710B79 /* OTPAlgorithm.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OTPAlgorithm.swift; sourceTree = "<group>"; };
+		D6147A1E26D14BA000710B79 /* TOTPCode.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TOTPCode.swift; sourceTree = "<group>"; };
+		D68B3D9F26D2937000CB35A2 /* AddURLForm.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AddURLForm.swift; sourceTree = "<group>"; };
+		D68B3DA126D293BE00CB35A2 /* DismissAction.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DismissAction.swift; sourceTree = "<group>"; };
+		D6A2BCAD26D29601004DC4E3 /* EditedKey.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EditedKey.swift; sourceTree = "<group>"; };
+		D6A2BCAF26D313E7004DC4E3 /* AddQRView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AddQRView.swift; sourceTree = "<group>"; };
+		D6A2BCCB26D3E670004DC4E3 /* PreferencesView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreferencesView.swift; sourceTree = "<group>"; };
+		D6A2BCCF26D3E888004DC4E3 /* BackupDocument.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BackupDocument.swift; sourceTree = "<group>"; };
+		D6A2BCEB26D3F7F9004DC4E3 /* QRCodeView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = QRCodeView.swift; sourceTree = "<group>"; };
+		D6A2BD0726D449FA004DC4E3 /* KeyData.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyData.swift; sourceTree = "<group>"; };
+		D6A2BD0926D44AC3004DC4E3 /* KeyStore.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyStore.swift; sourceTree = "<group>"; };
+		D6A2BD0B26D5332B004DC4E3 /* FolderView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FolderView.swift; sourceTree = "<group>"; };
+		D6A2BD0F26D533EB004DC4E3 /* FoldersSection.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FoldersSection.swift; sourceTree = "<group>"; };
+		D6A2BD1126D56C70004DC4E3 /* KeysSection.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeysSection.swift; sourceTree = "<group>"; };
+		D6A2BD1326D5707F004DC4E3 /* FolderRow.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FolderRow.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -31,16 +127,54 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				D60E9D7726D1B160009A4537 /* CodeScanner in Frameworks */,
+				D6147A0626D141F800710B79 /* OTPKit.framework in Frameworks */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		D61479EE26D141F700710B79 /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		D61479F726D141F800710B79 /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				D61479FB26D141F800710B79 /* OTPKit.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
+		D60E9D7826D1E976009A4537 /* Views */ = {
+			isa = PBXGroup;
+			children = (
+				D61479EA26D13DEF00710B79 /* AppView.swift */,
+				D6A2BD1126D56C70004DC4E3 /* KeysSection.swift */,
+				D6A2BD0F26D533EB004DC4E3 /* FoldersSection.swift */,
+				D6A2BD1326D5707F004DC4E3 /* FolderRow.swift */,
+				D60E9D7126D1A863009A4537 /* KeyView.swift */,
+				D60E9D7326D1ABF9009A4537 /* CircularProgressView.swift */,
+				D6A2BD0B26D5332B004DC4E3 /* FolderView.swift */,
+				D6A2BCAF26D313E7004DC4E3 /* AddQRView.swift */,
+				D68B3D9F26D2937000CB35A2 /* AddURLForm.swift */,
+				D60E9D7926D1E985009A4537 /* EditKeyForm.swift */,
+				D6A2BCCB26D3E670004DC4E3 /* PreferencesView.swift */,
+				D6A2BCEB26D3F7F9004DC4E3 /* QRCodeView.swift */,
+			);
+			path = Views;
+			sourceTree = "<group>";
+		};
 		D61479CA26D0AF1C00710B79 = {
 			isa = PBXGroup;
 			children = (
 				D61479D526D0AF1C00710B79 /* OTP */,
+				D61479F226D141F700710B79 /* OTPKit */,
+				D6147A0026D141F800710B79 /* OTPKitTests */,
 				D61479D426D0AF1C00710B79 /* Products */,
 			);
 			sourceTree = "<group>";
@@ -49,6 +183,8 @@
 			isa = PBXGroup;
 			children = (
 				D61479D326D0AF1C00710B79 /* OTP.app */,
+				D61479F126D141F700710B79 /* OTPKit.framework */,
+				D61479FA26D141F800710B79 /* OTPKitTests.xctest */,
 			);
 			name = Products;
 			sourceTree = "<group>";
@@ -56,19 +192,67 @@
 		D61479D526D0AF1C00710B79 /* OTP */ = {
 			isa = PBXGroup;
 			children = (
+				D61479E426D0AF1E00710B79 /* Info.plist */,
 				D61479D626D0AF1C00710B79 /* AppDelegate.swift */,
+				D6A2BCCF26D3E888004DC4E3 /* BackupDocument.swift */,
+				D68B3DA126D293BE00CB35A2 /* DismissAction.swift */,
+				D6A2BCAD26D29601004DC4E3 /* EditedKey.swift */,
+				D6A2BD0726D449FA004DC4E3 /* KeyData.swift */,
+				D6A2BD0926D44AC3004DC4E3 /* KeyStore.swift */,
 				D61479D826D0AF1C00710B79 /* SceneDelegate.swift */,
-				D61479DA26D0AF1C00710B79 /* ViewController.swift */,
-				D61479DC26D0AF1C00710B79 /* Main.storyboard */,
 				D61479DF26D0AF1E00710B79 /* Assets.xcassets */,
 				D61479E126D0AF1E00710B79 /* LaunchScreen.storyboard */,
-				D61479E426D0AF1E00710B79 /* Info.plist */,
+				D60E9D7826D1E976009A4537 /* Views */,
 			);
 			path = OTP;
 			sourceTree = "<group>";
 		};
+		D61479F226D141F700710B79 /* OTPKit */ = {
+			isa = PBXGroup;
+			children = (
+				D61479F426D141F700710B79 /* OTPKit.docc */,
+				D61479F326D141F700710B79 /* OTPKit.h */,
+				D6147A1C26D14B5F00710B79 /* OTPAlgorithm.swift */,
+				D6147A1826D14AAB00710B79 /* OTPGenerator.swift */,
+				D6147A1A26D14ADF00710B79 /* OTPKey.swift */,
+				D6147A1E26D14BA000710B79 /* TOTPCode.swift */,
+				D6147A0F26D1421900710B79 /* TOTPKey.swift */,
+				D6147A1126D1446500710B79 /* Vendor */,
+			);
+			path = OTPKit;
+			sourceTree = "<group>";
+		};
+		D6147A0026D141F800710B79 /* OTPKitTests */ = {
+			isa = PBXGroup;
+			children = (
+				D6147A0126D141F800710B79 /* OTPKitTests.swift */,
+				D60E9D6D26D1998B009A4537 /* OTPGeneratorTests.swift */,
+				D6147A1626D147B400710B79 /* TOTPKeyTests.swift */,
+			);
+			path = OTPKitTests;
+			sourceTree = "<group>";
+		};
+		D6147A1126D1446500710B79 /* Vendor */ = {
+			isa = PBXGroup;
+			children = (
+				D6147A1226D1446E00710B79 /* Base32.swift */,
+			);
+			path = Vendor;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
+/* Begin PBXHeadersBuildPhase section */
+		D61479EC26D141F700710B79 /* Headers */ = {
+			isa = PBXHeadersBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				D6147A0326D141F800710B79 /* OTPKit.h in Headers */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXHeadersBuildPhase section */
+
 /* Begin PBXNativeTarget section */
 		D61479D226D0AF1C00710B79 /* OTP */ = {
 			isa = PBXNativeTarget;
@@ -77,15 +261,57 @@
 				D61479CF26D0AF1C00710B79 /* Sources */,
 				D61479D026D0AF1C00710B79 /* Frameworks */,
 				D61479D126D0AF1C00710B79 /* Resources */,
+				D6147A0B26D141F800710B79 /* Embed Frameworks */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+				D6147A0526D141F800710B79 /* PBXTargetDependency */,
+			);
+			name = OTP;
+			packageProductDependencies = (
+				D60E9D7626D1B160009A4537 /* CodeScanner */,
+			);
+			productName = OTP;
+			productReference = D61479D326D0AF1C00710B79 /* OTP.app */;
+			productType = "com.apple.product-type.application";
+		};
+		D61479F026D141F700710B79 /* OTPKit */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = D6147A0826D141F800710B79 /* Build configuration list for PBXNativeTarget "OTPKit" */;
+			buildPhases = (
+				D61479EC26D141F700710B79 /* Headers */,
+				D61479ED26D141F700710B79 /* Sources */,
+				D61479EE26D141F700710B79 /* Frameworks */,
+				D61479EF26D141F700710B79 /* Resources */,
 			);
 			buildRules = (
 			);
 			dependencies = (
 			);
-			name = OTP;
+			name = OTPKit;
-			productName = OTP;
+			productName = OTPKit;
-			productReference = D61479D326D0AF1C00710B79 /* OTP.app */;
+			productReference = D61479F126D141F700710B79 /* OTPKit.framework */;
-			productType = "com.apple.product-type.application";
+			productType = "com.apple.product-type.framework";
+		};
+		D61479F926D141F800710B79 /* OTPKitTests */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = D6147A0C26D141F800710B79 /* Build configuration list for PBXNativeTarget "OTPKitTests" */;
+			buildPhases = (
+				D61479F626D141F800710B79 /* Sources */,
+				D61479F726D141F800710B79 /* Frameworks */,
+				D61479F826D141F800710B79 /* Resources */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+				D61479FD26D141F800710B79 /* PBXTargetDependency */,
+				D61479FF26D141F800710B79 /* PBXTargetDependency */,
+			);
+			name = OTPKitTests;
+			productName = OTPKitTests;
+			productReference = D61479FA26D141F800710B79 /* OTPKitTests.xctest */;
+			productType = "com.apple.product-type.bundle.unit-test";
 		};
 /* End PBXNativeTarget section */
 
@@ -100,6 +326,13 @@
 					D61479D226D0AF1C00710B79 = {
 						CreatedOnToolsVersion = 13.0;
 					};
+					D61479F026D141F700710B79 = {
+						CreatedOnToolsVersion = 13.0;
+					};
+					D61479F926D141F800710B79 = {
+						CreatedOnToolsVersion = 13.0;
+						TestTargetID = D61479D226D0AF1C00710B79;
+					};
 				};
 			};
 			buildConfigurationList = D61479CE26D0AF1C00710B79 /* Build configuration list for PBXProject "OTP" */;
@@ -111,11 +344,16 @@
 				Base,
 			);
 			mainGroup = D61479CA26D0AF1C00710B79;
+			packageReferences = (
+				D60E9D7526D1B160009A4537 /* XCRemoteSwiftPackageReference "CodeScanner" */,
+			);
 			productRefGroup = D61479D426D0AF1C00710B79 /* Products */;
 			projectDirPath = "";
 			projectRoot = "";
 			targets = (
 				D61479D226D0AF1C00710B79 /* OTP */,
+				D61479F026D141F700710B79 /* OTPKit */,
+				D61479F926D141F800710B79 /* OTPKitTests */,
 			);
 		};
 /* End PBXProject section */
@@ -127,7 +365,20 @@
 			files = (
 				D61479E326D0AF1E00710B79 /* LaunchScreen.storyboard in Resources */,
 				D61479E026D0AF1E00710B79 /* Assets.xcassets in Resources */,
-				D61479DE26D0AF1C00710B79 /* Main.storyboard in Resources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		D61479EF26D141F700710B79 /* Resources */ = {
+			isa = PBXResourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		D61479F826D141F800710B79 /* Resources */ = {
+			isa = PBXResourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -138,23 +389,73 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				D61479DB26D0AF1C00710B79 /* ViewController.swift in Sources */,
 				D61479D726D0AF1C00710B79 /* AppDelegate.swift in Sources */,
+				D6A2BCCC26D3E670004DC4E3 /* PreferencesView.swift in Sources */,
+				D6A2BD0C26D5332B004DC4E3 /* FolderView.swift in Sources */,
 				D61479D926D0AF1C00710B79 /* SceneDelegate.swift in Sources */,
+				D6A2BD1026D533EB004DC4E3 /* FoldersSection.swift in Sources */,
+				D6A2BCAE26D29601004DC4E3 /* EditedKey.swift in Sources */,
+				D6A2BD1426D5707F004DC4E3 /* FolderRow.swift in Sources */,
+				D6A2BCD026D3E888004DC4E3 /* BackupDocument.swift in Sources */,
+				D6A2BD1226D56C70004DC4E3 /* KeysSection.swift in Sources */,
+				D60E9D7226D1A863009A4537 /* KeyView.swift in Sources */,
+				D68B3DA026D2937000CB35A2 /* AddURLForm.swift in Sources */,
+				D61479EB26D13DEF00710B79 /* AppView.swift in Sources */,
+				D68B3DA226D293BE00CB35A2 /* DismissAction.swift in Sources */,
+				D60E9D7426D1ABF9009A4537 /* CircularProgressView.swift in Sources */,
+				D6A2BCEC26D3F7F9004DC4E3 /* QRCodeView.swift in Sources */,
+				D60E9D7A26D1E985009A4537 /* EditKeyForm.swift in Sources */,
+				D6A2BD0A26D44AC3004DC4E3 /* KeyStore.swift in Sources */,
+				D6A2BCB026D313E7004DC4E3 /* AddQRView.swift in Sources */,
+				D6A2BD0826D449FA004DC4E3 /* KeyData.swift in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		D61479ED26D141F700710B79 /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				D61479F526D141F700710B79 /* OTPKit.docc in Sources */,
+				D6147A1F26D14BA000710B79 /* TOTPCode.swift in Sources */,
+				D6147A1326D1446E00710B79 /* Base32.swift in Sources */,
+				D6147A1026D1421900710B79 /* TOTPKey.swift in Sources */,
+				D6147A1D26D14B5F00710B79 /* OTPAlgorithm.swift in Sources */,
+				D6147A1926D14AAB00710B79 /* OTPGenerator.swift in Sources */,
+				D6147A1B26D14ADF00710B79 /* OTPKey.swift in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		D61479F626D141F800710B79 /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				D6147A1726D147B400710B79 /* TOTPKeyTests.swift in Sources */,
+				D6147A0226D141F800710B79 /* OTPKitTests.swift in Sources */,
+				D60E9D6E26D1998B009A4537 /* OTPGeneratorTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 /* End PBXSourcesBuildPhase section */
 
-/* Begin PBXVariantGroup section */
+/* Begin PBXTargetDependency section */
-		D61479DC26D0AF1C00710B79 /* Main.storyboard */ = {
+		D61479FD26D141F800710B79 /* PBXTargetDependency */ = {
-			isa = PBXVariantGroup;
+			isa = PBXTargetDependency;
-			children = (
+			target = D61479F026D141F700710B79 /* OTPKit */;
-				D61479DD26D0AF1C00710B79 /* Base */,
+			targetProxy = D61479FC26D141F800710B79 /* PBXContainerItemProxy */;
-			);
-			name = Main.storyboard;
-			sourceTree = "<group>";
 		};
+		D61479FF26D141F800710B79 /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			target = D61479D226D0AF1C00710B79 /* OTP */;
+			targetProxy = D61479FE26D141F800710B79 /* PBXContainerItemProxy */;
+		};
+		D6147A0526D141F800710B79 /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			target = D61479F026D141F700710B79 /* OTPKit */;
+			targetProxy = D6147A0426D141F800710B79 /* PBXContainerItemProxy */;
+		};
+/* End PBXTargetDependency section */
+
+/* Begin PBXVariantGroup section */
 		D61479E126D0AF1E00710B79 /* LaunchScreen.storyboard */ = {
 			isa = PBXVariantGroup;
 			children = (
@@ -285,6 +586,7 @@
 		D61479E826D0AF1E00710B79 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_STYLE = Automatic;
@@ -294,9 +596,9 @@
 				INFOPLIST_FILE = OTP/Info.plist;
 				INFOPLIST_KEY_UIApplicationSupportsIndirectInputEvents = YES;
 				INFOPLIST_KEY_UILaunchStoryboardName = LaunchScreen;
-				INFOPLIST_KEY_UIMainStoryboardFile = Main;
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
+				IPHONEOS_DEPLOYMENT_TARGET = 15.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -313,6 +615,7 @@
 		D61479E926D0AF1E00710B79 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_STYLE = Automatic;
@@ -322,9 +625,9 @@
 				INFOPLIST_FILE = OTP/Info.plist;
 				INFOPLIST_KEY_UIApplicationSupportsIndirectInputEvents = YES;
 				INFOPLIST_KEY_UILaunchStoryboardName = LaunchScreen;
-				INFOPLIST_KEY_UIMainStoryboardFile = Main;
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
+				IPHONEOS_DEPLOYMENT_TARGET = 15.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -338,6 +641,112 @@
 			};
 			name = Release;
 		};
+		D6147A0926D141F800710B79 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				DEFINES_MODULE = YES;
+				DEVELOPMENT_TEAM = V4WK9KR9U2;
+				DYLIB_COMPATIBILITY_VERSION = 1;
+				DYLIB_CURRENT_VERSION = 1;
+				DYLIB_INSTALL_NAME_BASE = "@rpath";
+				GENERATE_INFOPLIST_FILE = YES;
+				INFOPLIST_KEY_NSHumanReadableCopyright = "";
+				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+					"@loader_path/Frameworks",
+				);
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = net.shadowfacts.OTPKit;
+				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
+				SKIP_INSTALL = YES;
+				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+				VERSIONING_SYSTEM = "apple-generic";
+				VERSION_INFO_PREFIX = "";
+			};
+			name = Debug;
+		};
+		D6147A0A26D141F800710B79 /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				DEFINES_MODULE = YES;
+				DEVELOPMENT_TEAM = V4WK9KR9U2;
+				DYLIB_COMPATIBILITY_VERSION = 1;
+				DYLIB_CURRENT_VERSION = 1;
+				DYLIB_INSTALL_NAME_BASE = "@rpath";
+				GENERATE_INFOPLIST_FILE = YES;
+				INFOPLIST_KEY_NSHumanReadableCopyright = "";
+				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+					"@loader_path/Frameworks",
+				);
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = net.shadowfacts.OTPKit;
+				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
+				SKIP_INSTALL = YES;
+				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+				VERSIONING_SYSTEM = "apple-generic";
+				VERSION_INFO_PREFIX = "";
+			};
+			name = Release;
+		};
+		D6147A0D26D141F800710B79 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				DEVELOPMENT_TEAM = V4WK9KR9U2;
+				GENERATE_INFOPLIST_FILE = YES;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+					"@loader_path/Frameworks",
+				);
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = net.shadowfacts.OTPKitTests;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_EMIT_LOC_STRINGS = NO;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/OTP.app/OTP";
+			};
+			name = Debug;
+		};
+		D6147A0E26D141F800710B79 /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				DEVELOPMENT_TEAM = V4WK9KR9U2;
+				GENERATE_INFOPLIST_FILE = YES;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+					"@loader_path/Frameworks",
+				);
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = net.shadowfacts.OTPKitTests;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_EMIT_LOC_STRINGS = NO;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/OTP.app/OTP";
+			};
+			name = Release;
+		};
 /* End XCBuildConfiguration section */
 
 /* Begin XCConfigurationList section */
@@ -359,7 +768,44 @@
 			defaultConfigurationIsVisible = 0;
 			defaultConfigurationName = Release;
 		};
+		D6147A0826D141F800710B79 /* Build configuration list for PBXNativeTarget "OTPKit" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				D6147A0926D141F800710B79 /* Debug */,
+				D6147A0A26D141F800710B79 /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+		D6147A0C26D141F800710B79 /* Build configuration list for PBXNativeTarget "OTPKitTests" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				D6147A0D26D141F800710B79 /* Debug */,
+				D6147A0E26D141F800710B79 /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
 /* End XCConfigurationList section */
+
+/* Begin XCRemoteSwiftPackageReference section */
+		D60E9D7526D1B160009A4537 /* XCRemoteSwiftPackageReference "CodeScanner" */ = {
+			isa = XCRemoteSwiftPackageReference;
+			repositoryURL = "https://github.com/twostraws/CodeScanner";
+			requirement = {
+				kind = upToNextMajorVersion;
+				minimumVersion = 1.0.0;
+			};
+		};
+/* End XCRemoteSwiftPackageReference section */
+
+/* Begin XCSwiftPackageProductDependency section */
+		D60E9D7626D1B160009A4537 /* CodeScanner */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = D60E9D7526D1B160009A4537 /* XCRemoteSwiftPackageReference "CodeScanner" */;
+			productName = CodeScanner;
+		};
+/* End XCSwiftPackageProductDependency section */
 	};
 	rootObject = D61479CB26D0AF1C00710B79 /* Project object */;
 }

OTP.xcodeproj/xcuserdata/shadowfacts.xcuserdatad/xcschemes/xcschememanagement.plist

@@ -5,6 +5,11 @@
 	<key>SchemeUserState</key>
 	<dict>
 		<key>OTP.xcscheme_^#shared#^_</key>
+		<dict>
+			<key>orderHint</key>
+			<integer>1</integer>
+		</dict>
+		<key>OTPKit.xcscheme_^#shared#^_</key>
 		<dict>
 			<key>orderHint</key>
 			<integer>0</integer>

OTP/AppDelegate.swift

@@ -11,9 +11,7 @@ import UIKit
 class AppDelegate: UIResponder, UIApplicationDelegate {
 
 
-
     func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
-        // Override point for customization after application launch.
         return true
     }
 

OTP/BackupDocument.swift

@@ -0,0 +1,45 @@
+//
+//  BackupDocument.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/23/21.
+//
+
+import SwiftUI
+import UniformTypeIdentifiers
+import OTPKit
+
+struct BackupDocument: FileDocument {
+    
+    private static let encoder = PropertyListEncoder()
+    private static let decoder = PropertyListDecoder()
+    
+    static var readableContentTypes: [UTType] { [.propertyList] }
+    
+    private(set) var data: KeyData
+    
+    init(data: KeyData) {
+        self.data = data
+    }
+    
+    init(configuration: ReadConfiguration) throws {
+        if let data = configuration.file.regularFileContents {
+            let store = try BackupDocument.decoder.decode(KeyData.self, from: data)
+            self.data = store
+        } else {
+            self.data = KeyData()
+        }
+    }
+    
+    init(url: URL) throws {
+        let data = try Data(contentsOf: url)
+        let store = try BackupDocument.decoder.decode(KeyData.self, from: data)
+        self.data = store
+    }
+    
+    func fileWrapper(configuration: WriteConfiguration) throws -> FileWrapper {
+        let data = try! BackupDocument.encoder.encode(data)
+        return FileWrapper(regularFileWithContents: data)
+    }
+    
+}

OTP/Base.lproj/Main.storyboard

@@ -1,24 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="13122.16" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
-    <dependencies>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13104.12"/>
-        <capability name="Safe area layout guides" minToolsVersion="9.0"/>
-        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
-    </dependencies>
-    <scenes>
-        <!--View Controller-->
-        <scene sceneID="tne-QT-ifu">
-            <objects>
-                <viewController id="BYZ-38-t0r" customClass="ViewController" customModuleProvider="target" sceneMemberID="viewController">
-                    <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
-                        <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
-                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
-                        <color key="backgroundColor" xcode11CocoaTouchSystemColor="systemBackgroundColor" cocoaTouchSystemColor="whiteColor"/>
-                        <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
-                    </view>
-                </viewController>
-                <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
-            </objects>
-        </scene>
-    </scenes>
-</document>

OTP/DismissAction.swift

@@ -0,0 +1,14 @@
+//
+//  DismissAction.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/22/21.
+//
+
+import Foundation
+import OTPKit
+
+enum DismissAction {
+    case cancel
+    case save(TOTPKey)
+}

OTP/EditedKey.swift

@@ -0,0 +1,74 @@
+//
+//  EditedKey.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/22/21.
+//
+
+import Foundation
+import OTPKit
+
+struct EditedKey {
+    var secret: String
+    var period: Period
+    var digits: Digits
+    var issuer: String
+    var label: String
+    
+    init() {
+        self.secret = ""
+        self.period = .thirty
+        self.digits = .six
+        self.issuer = ""
+        self.label = ""
+    }
+    
+    init?(totpKey: TOTPKey) {
+        guard totpKey.period == 30 || totpKey.period == 60,
+              totpKey.digits == 6 || totpKey.digits == 8 else {
+            return nil
+        }
+
+        self.secret = totpKey.secret.base32EncodedString
+        self.period = totpKey.period == 30 ? .thirty : .sixty
+        self.digits = totpKey.digits == 6 ? .six : .eight
+        self.issuer = totpKey.issuer
+        self.label = totpKey.label ?? ""
+    }
+    
+    func toTOTPKey() -> TOTPKey? {
+        let secretStr = self.secret.replacingOccurrences(of: " ", with: "")
+        guard secretStr.count > 0,
+              let secret = secretStr.base32DecodedData,
+              !issuer.isEmpty else {
+            return nil
+        }
+        return TOTPKey(secret: secret, period: period.value, digits: digits.value, label: label.trimmingCharacters(in: .whitespacesAndNewlines), issuer: issuer)
+    }
+    
+    enum Period: Hashable {
+        case thirty, sixty
+        
+        var value: Int {
+            switch self {
+            case .thirty:
+                return 30
+            case .sixty:
+                return 60
+            }
+        }
+    }
+    
+    enum Digits: Hashable {
+        case six, eight
+        
+        var value: Int {
+            switch self {
+            case .six:
+                return 6
+            case .eight:
+                return 8
+            }
+        }
+    }
+}

OTP/Info.plist

@@ -2,6 +2,10 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>NSPhotoLibraryAddUsageDescription</key>
+	<string>Save exported QR codes</string>
+	<key>NSCameraUsageDescription</key>
+	<string>Scan OTP keys from QR codes</string>
 	<key>UIApplicationSceneManifest</key>
 	<dict>
 		<key>UIApplicationSupportsMultipleScenes</key>
@@ -15,8 +19,6 @@
 					<string>Default Configuration</string>
 					<key>UISceneDelegateClassName</key>
 					<string>$(PRODUCT_MODULE_NAME).SceneDelegate</string>
-					<key>UISceneStoryboardFile</key>
-					<string>Main</string>
 				</dict>
 			</array>
 		</dict>

OTP/KeyData.swift

@@ -0,0 +1,121 @@
+//
+//  KeyData.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/23/21.
+//
+
+import Foundation
+import OTPKit
+
+struct KeyData: Codable {
+    
+    private(set) var entries: [Entry] = []
+    private(set) var folders: [Folder] = []
+    
+    init(entries: [Entry] = []) {
+        self.entries = entries
+    }
+    
+    init(from decoder: Decoder) throws {
+        let container = try decoder.container(keyedBy: CodingKeys.self)
+        self.entries = try container.decode([Entry].self, forKey: .entries)
+        self.folders = try container.decode([Folder].self, forKey: .folders)
+    }
+    
+    func encode(to encoder: Encoder) throws {
+        var container = encoder.container(keyedBy: CodingKeys.self)
+        try container.encode(entries, forKey: .entries)
+        try container.encode(folders, forKey: .folders)
+    }
+    
+    mutating func addKey(_ key: TOTPKey) {
+        entries.append(Entry(key: key))
+    }
+    
+    mutating func addOrUpdateEntries(_ entries: [Entry]) {
+        for e in entries {
+            if let index = self.entries.firstIndex(where: { $0.id == e.id }) {
+                self.entries[index] = e
+            } else {
+                self.entries.append(e)
+            }
+        }
+    }
+    
+    mutating func updateKey(entryID id: UUID, newKey: TOTPKey) {
+        guard let index = entries.firstIndex(where: { $0.id == id }) else {
+            return
+        }
+        entries[index].key = newKey
+    }
+    
+    mutating func removeKey(entryID id: UUID) {
+        entries.removeAll(where: { $0.id == id })
+    }
+    
+    mutating func clearEntries() {
+        entries.removeAll()
+    }
+    
+    mutating func addFolder() {
+        let count = folders.filter { $0.name.starts(with: "New Folder") }.count
+        if count > 0 {
+            folders.append(Folder(name: "New Folder \(count + 1)"))
+        } else {
+            folders.append(Folder(name: "New Folder"))
+        }
+    }
+    
+    mutating func updateFolder(_ newFolder: KeyData.Folder) {
+        guard let index = folders.firstIndex(where: { $0.id == newFolder.id }) else {
+            return
+        }
+        folders[index] = newFolder
+    }
+    
+    mutating func removeFolder(id: UUID) {
+        folders.removeAll(where: { $0.id == id })
+        for (index, e) in entries.enumerated() where e.folderID == id {
+            entries[index].folderID = nil
+        }
+    }
+    
+    mutating func moveEntryToFolder(entryID: UUID, folderID: UUID?) {
+        guard let index = entries.firstIndex(where: { $0.id == entryID }),
+              folderID == nil || folders.contains(where: { $0.id == folderID }) else {
+            return
+        }
+        entries[index].folderID = folderID
+    }
+    
+    struct Entry: Identifiable, Hashable, Codable {
+        let id: UUID
+        var key: TOTPKey
+        var folderID: UUID?
+        let image: Data?
+        
+        init(id: UUID = UUID(), key: TOTPKey, folderID: UUID? = nil, image: Data? = nil) {
+            self.id = id
+            self.key = key
+            self.folderID = folderID
+            self.image = image
+        }
+    }
+    
+    struct Folder: Identifiable, Codable {
+        let id: UUID
+        var name: String
+        
+        init(id: UUID = UUID(), name: String) {
+            self.id = id
+            self.name = name
+        }
+    }
+    
+    private enum CodingKeys: CodingKey {
+        case entries
+        case folders
+    }
+    
+}

OTP/KeyStore.swift

@@ -0,0 +1,89 @@
+//
+//  KeyStore.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/23/21.
+//
+
+import Foundation
+import OTPKit
+import Security
+import Combine
+
+class KeyStore: ObservableObject {
+    static let shared = try! KeyStore()
+    
+    private lazy var documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
+    private lazy var storeArchiveURL = documentsDirectory.appendingPathComponent("KeyStore").appendingPathExtension("plist")
+    
+    private let encoder = PropertyListEncoder()
+    private let decoder = PropertyListDecoder()
+    
+    @Published private(set) var data: KeyData! {
+        didSet {
+            let data = try! encoder.encode(data)
+            try! data.write(to: storeArchiveURL, options: .completeFileProtectionUntilFirstUserAuthentication)
+        }
+    }
+    
+    var entries: [KeyData.Entry] {
+        data.entries
+    }
+    
+    var folders: [KeyData.Folder] {
+        data.folders
+    }
+    
+    var sortedFolders: [KeyData.Folder] {
+        data.folders.sorted(by: { (a, b) in a.name < b.name })
+    }
+
+    private init() throws {
+        if let data = try? Data(contentsOf: storeArchiveURL) {
+            self.data = try decoder.decode(KeyData.self, from: data)
+        } else {
+            self.data = KeyData()
+        }
+    }
+    
+    func updateFromStore(_ newStore: KeyData, replaceExisting: Bool) {
+        if replaceExisting {
+            data = newStore
+        } else {
+            data.addOrUpdateEntries(newStore.entries)
+        }
+    }
+    
+    func addKey(_ key: TOTPKey) {
+        data.addKey(key)
+    }
+    
+    func updateKey(entryID id: UUID, newKey: TOTPKey) {
+        data.updateKey(entryID: id, newKey: newKey)
+    }
+    
+    func removeKey(entryID id: UUID) {
+        data.removeKey(entryID: id)
+    }
+    
+    func clearEntries() {
+        data.clearEntries()
+    }
+    
+    func addFolder() {
+        data.addFolder()
+    }
+    
+    func updateFolder(_ newFolder: KeyData.Folder) {
+        data.updateFolder(newFolder)
+    }
+    
+    func removeFolder(id: UUID) {
+        data.removeFolder(id: id)
+    }
+    
+    func moveEntryToFolder(entryID: UUID, folderID: UUID?) {
+        data.moveEntryToFolder(entryID: entryID, folderID: folderID)
+    }
+    
+}

OTP/SceneDelegate.swift

@@ -6,17 +6,23 @@
 //
 
 import UIKit
+import SwiftUI
 
 class SceneDelegate: UIResponder, UIWindowSceneDelegate {
 
     var window: UIWindow?
 
-
     func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
         // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
         // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
         // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
-        guard let _ = (scene as? UIWindowScene) else { return }
+        guard let windowScene = scene as? UIWindowScene else { return }
+        
+        window = UIWindow(windowScene: windowScene)
+        
+        window!.rootViewController = UIHostingController(rootView: AppView())
+        
+        window!.makeKeyAndVisible()
     }
 
     func sceneDidDisconnect(_ scene: UIScene) {

OTP/ViewController.swift

@@ -1,19 +0,0 @@
-//
-//  ViewController.swift
-//  OTP
-//
-//  Created by Shadowfacts on 8/20/21.
-//
-
-import UIKit
-
-class ViewController: UIViewController {
-
-    override func viewDidLoad() {
-        super.viewDidLoad()
-        // Do any additional setup after loading the view.
-    }
-
-
-}
-

OTP/Views/AddQRView.swift

@@ -0,0 +1,95 @@
+//
+//  AddQRView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/22/21.
+//
+
+import SwiftUI
+import CodeScanner
+import OTPKit
+
+struct AddQRView: View {
+    let dismiss: (DismissAction) -> Void
+    @State private var isPresentingScanFailedAlert = false
+    @State private var scanError: ScanError?
+    @State private var scannedKey: TOTPKey?
+    @State private var isShowingConfirmView = false
+    
+    var body: some View {
+        NavigationView {
+            CodeScannerView(codeTypes: [.qr], scanMode: .once) { (result) in
+                switch result {
+                case .success(let code):
+                    if let components = URLComponents(string: code),
+                       let key = TOTPKey(urlComponents: components) {
+                        self.scannedKey = key
+                        isShowingConfirmView = true
+                    } else {
+                        isPresentingScanFailedAlert = true
+                        scanError = .invalidCode(code)
+                    }
+                case .failure(let error):
+                    isPresentingScanFailedAlert = true
+                    scanError = .scanner(error)
+                }
+            }
+            .edgesIgnoringSafeArea(.bottom)
+            .navigationBarTitle("Scan QR Code", displayMode: .inline)
+            .toolbar {
+                ToolbarItem(placement: .navigationBarLeading) {
+                    Button("Cancel") {
+                        dismiss(.cancel)
+                    }
+                }
+            }
+            .overlay {
+                NavigationLink(isActive: $isShowingConfirmView) {
+                    EditKeyForm(editingKey: scannedKey, showCancelButton: false, dismiss: dismiss)
+                        .navigationTitle("Add Key")
+                } label: {
+                    // EmptyView because this is only used to trigger programatic navigation
+                    EmptyView()
+                }
+
+            }
+        }
+        .alert("Unable to get OTP key from QR code", isPresented: $isPresentingScanFailedAlert) {
+            Button("Cancel", role: .cancel) {
+                dismiss(.cancel)
+            }
+            Button("Try Again") {
+                isPresentingScanFailedAlert = false
+            }
+        } message: {
+            if let error = scanError {
+                Text(error.localizedDescription)
+            }
+        }
+    }
+    
+}
+
+extension AddQRView {
+    enum ScanError: LocalizedError {
+        case scanner(CodeScannerView.ScanError)
+        case invalidCode(String)
+        
+        var errorDescription: String? {
+            switch self {
+            case .invalidCode(let code):
+                return "Invalid Code: '\(code)'"
+            case .scanner(.badInput):
+                return "Scanner: Bad Input"
+            case .scanner(.badOutput):
+                return "Scanner: Bad Output"
+            }
+        }
+    }
+}
+
+struct AddQRView_Previews: PreviewProvider {
+    static var previews: some View {
+        AddQRView() { (_) in }
+    }
+}

OTP/Views/AddURLForm.swift

@@ -0,0 +1,90 @@
+//
+//  AddURLForm.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/22/21.
+//
+
+import SwiftUI
+import OTPKit
+
+struct AddURLForm: View {
+    let dismiss: (DismissAction) -> Void
+    @State private var inputURL = ""
+    @State private var extractedKey = EditedKey()
+    @FocusState private var urlFocused: Bool
+    
+    private var isValid: Bool {
+        extractedKey.toTOTPKey() != nil
+    }
+    
+    var body: some View {
+        Form {
+            HStack {
+                TextField("URL", text: $inputURL)
+                    .focused($urlFocused)
+                
+                Button {
+                    self.inputURL = UIPasteboard.general.string ?? ""
+                } label: {
+                    Label("Paste", systemImage: "doc.on.clipboard")
+                        .labelStyle(.iconOnly)
+                        .foregroundColor(.accentColor)
+                }
+                .buttonStyle(.plain)
+                .disabled(!UIPasteboard.general.hasStrings)
+            }
+            
+            Section {
+                TextField("Issuer", text: $extractedKey.issuer)
+                TextField("Label", text: $extractedKey.label)
+                TextField("Secret", text: $extractedKey.secret)
+            } header: {
+                Text("Extracted Key")
+            }
+            .disabled(true)
+        }
+        .onSubmit {
+            if isValid {
+                dismiss(.save(extractedKey.toTOTPKey()!))
+            }
+        }
+        .onAppear {
+            // doesn't work, see FB9551099
+            urlFocused = true
+        }
+        .navigationTitle("Add from URL")
+        .toolbar {
+            ToolbarItem(placement: .navigationBarLeading) {
+                Button("Cancel") {
+                    dismiss(.cancel)
+                }
+            }
+            ToolbarItem(placement: .navigationBarTrailing) {
+                Button("Save") {
+                    dismiss(.save(extractedKey.toTOTPKey()!))
+                }
+                .disabled(!isValid)
+            }
+        }
+        .onChange(of: inputURL, perform: self.updateExtractedKey(inputURL:))
+    }
+    
+    private func updateExtractedKey(inputURL: String) {
+        let text = inputURL.trimmingCharacters(in: .whitespacesAndNewlines)
+        if !text.isEmpty,
+           let components = URLComponents(string: inputURL),
+           let totpKey = TOTPKey(urlComponents: components),
+           let edited = EditedKey(totpKey: totpKey) {
+            extractedKey = edited
+        } else {
+            extractedKey = EditedKey()
+        }
+    }
+}
+
+struct AddURLForm_Previews: PreviewProvider {
+    static var previews: some View {
+        AddURLForm() { (_) in }
+    }
+}

OTP/Views/AppView.swift

@@ -0,0 +1,210 @@
+//
+//  AppView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import SwiftUI
+import OTPKit
+import Combine
+
+struct AppView: View {
+    @ObservedObject private var store: KeyStore
+    @ObservedObject private var entryHolder: CodeHolder
+    @State private var isPresentingScanner = false
+    @State private var isPresentingScanFailedAlert = false
+    @State private var isPresentingAddURLSheet = false
+    @State private var isPresentingManualAddFormSheet = false
+    @State private var isPresentingPreferences = false
+    
+    init() {
+        self.store = .shared
+        self.entryHolder = CodeHolder(store: .shared) { (entry) in entry.folderID == nil }
+    }
+    
+    var body: some View {
+        NavigationView {
+            List {
+                KeysSection(codeHolder: entryHolder)
+                
+                FoldersSection()
+            }
+            .listStyle(.insetGrouped)
+            .navigationTitle("OTP")
+            .toolbar {
+                ToolbarItem(placement: .navigationBarLeading) {
+                    Button {
+                        isPresentingPreferences = true
+                    } label: {
+                        Label("Preferences", systemImage: "gear")
+                    }
+                }
+                
+                ToolbarItem(placement: .navigationBarTrailing) {
+                    Menu {
+                        Section {
+                            Button {
+                                isPresentingScanner = true
+                            } label: {
+                                Label("Scan QR", systemImage: "qrcode.viewfinder")
+                            }
+                            Button {
+                                isPresentingAddURLSheet = true
+                            } label: {
+                                Label("From URL", systemImage: "link")
+                            }
+                            Button {
+                                isPresentingManualAddFormSheet = true
+                            } label: {
+                                Label("Enter Manually", systemImage: "textbox")
+                            }
+                        }
+                        
+                        Section {
+                            Button {
+                                store.addFolder()
+                            } label: {
+                                Label("New Folder", systemImage: "folder.badge.plus")
+                            }
+                        }
+                    } label: {
+                        Label("Add Key", systemImage: "plus.circle")
+                    }
+                }
+            }
+        }
+        .tint(.blue)
+        .sheet(isPresented: $isPresentingPreferences, content: self.preferencesSheet)
+        .sheet(isPresented: $isPresentingScanner, content: self.scannerSheet)
+        .sheet(isPresented: $isPresentingManualAddFormSheet, content: self.manualAddFormSheet)
+        .sheet(isPresented: $isPresentingAddURLSheet, content: self.addURLSheet)
+    }
+    
+    private func preferencesSheet() -> some View {
+        NavigationView {
+            PreferencesView()
+        }
+    }
+    
+    private func scannerSheet() -> some View {
+        AddQRView() { (action) in
+            self.isPresentingScanner = false
+            switch action {
+            case .cancel:
+                break
+            case .save(let key):
+                store.addKey(key)
+            }
+        }
+    }
+    
+    private func addURLSheet() -> some View {
+        NavigationView {
+            AddURLForm { (action) in
+                self.isPresentingAddURLSheet = false
+                switch action {
+                case .cancel:
+                    break
+                case .save(let key):
+                    store.addKey(key)
+                }
+            }
+        }
+    }
+    
+    private func manualAddFormSheet() -> some View {
+        NavigationView {
+            EditKeyForm(editingKey: nil, focusOnAppear: true) { (action) in
+                self.isPresentingManualAddFormSheet = false
+                switch action {
+                case .cancel:
+                    break
+                case .save(let key):
+                    store.addKey(key)
+                }
+            }
+            .navigationTitle("Add Key")
+        }
+    }
+    
+    struct CodeEntry: Identifiable, Equatable, Hashable {
+        let entry: KeyData.Entry
+        let code: TOTPCode
+        var key: TOTPKey { entry.key }
+        var id: UUID { entry.id }
+        
+        init(_ entry: KeyData.Entry) {
+            self.entry = entry
+            self.code = OTPGenerator.generate(key: entry.key)
+        }
+    }
+    
+    class CodeHolder: ObservableObject {
+        private let store: KeyStore
+        private let entryFilter: ((KeyData.Entry) -> Bool)?
+        private var timer: Timer!
+        private var cancellables = Set<AnyCancellable>()
+        
+        init(store: KeyStore, entryFilter: ((KeyData.Entry) -> Bool)? = nil) {
+            self.store = store
+            self.entryFilter = entryFilter
+            
+            updateTimer(entries: filterEntries(from: store.data))
+            
+            store.$data
+                .sink { [unowned self] (newData) in
+                    self.objectWillChange.send()
+                    self.updateTimer(entries: filterEntries(from: newData!))
+                }
+                .store(in: &cancellables)
+        }
+        
+        var entries: [CodeEntry] {
+            return filterEntries(from: store.data).map { CodeEntry($0) }
+        }
+        
+        var sortedEntries: [CodeEntry] {
+            return entries.sorted(by: { (a, b) in
+                if a.key.issuer == b.key.issuer,
+                   let aLabel = a.key.label,
+                   let bLabel = b.key.label {
+                    return aLabel < bLabel
+                } else {
+                    return a.key.issuer < b.key.issuer
+                }
+            })
+        }
+        
+        private func filterEntries(from data: KeyData) -> [KeyData.Entry] {
+            if let filter = entryFilter {
+                return data.entries.filter(filter)
+            } else {
+                return data.entries
+            }
+        }
+        
+        private func updateTimer(entries: [KeyData.Entry]) {
+            if entries.isEmpty {
+                timer?.invalidate()
+                return
+            } else if timer == nil || !timer.isValid {
+                timer = .scheduledTimer(withTimeInterval: 0.5, repeats: true) { [weak self] (timer) in
+                    guard let self = self else {
+                        timer.invalidate()
+                        return
+                    }
+                    self.objectWillChange.send()
+                }
+                timer.tolerance = 0.01
+            }
+        }
+    }
+    
+}
+
+struct AppView_Previews: PreviewProvider {
+    static var previews: some View {
+        AppView()
+    }
+}

OTP/Views/CircularProgressView.swift

@@ -0,0 +1,39 @@
+//
+//  CircularProgressView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import SwiftUI
+
+struct CircularProgressView: View {
+    let progress: Double
+    let colorChangeThreshold: Double
+    
+    var body: some View {
+        ZStack {
+            Circle()
+                .stroke(lineWidth: 4)
+                .foregroundColor(progress <= colorChangeThreshold ? .red : .accentColor)
+                .opacity(0.4)
+                .animation(.default, value: progress)
+            
+            Circle()
+                .trim(from: 0, to: progress)
+                .stroke(lineWidth: 4)
+                .foregroundColor(progress <= colorChangeThreshold ? .red : .accentColor)
+                .rotationEffect(.degrees(270))
+                .animation(.default, value: progress)
+
+        }
+        .aspectRatio(1, contentMode: .fit)
+    }
+}
+
+struct CircularProgressView_Previews: PreviewProvider {
+    static var previews: some View {
+        CircularProgressView(progress: 0.6, colorChangeThreshold: 0)
+            .frame(width: 30)
+    }
+}

OTP/Views/EditKeyForm.swift

@@ -0,0 +1,113 @@
+//
+//  EditKeyForm.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import SwiftUI
+import OTPKit
+
+struct EditKeyForm: View {
+    let dismiss: (DismissAction) -> Void
+    let showCancelButton: Bool
+    let focusOnAppear: Bool
+    @State private var editedKey: EditedKey
+    @FocusState private var issuerFocused: Bool
+    
+    init(editingKey: TOTPKey?, showCancelButton: Bool = true, focusOnAppear: Bool = false, dismiss: @escaping (DismissAction) -> Void) {
+        self.dismiss = dismiss
+        self.showCancelButton = showCancelButton
+        self.focusOnAppear = focusOnAppear
+        if let totpKey = editingKey,
+           let edited = EditedKey(totpKey: totpKey) {
+            self.editedKey = edited
+        } else {
+            self.editedKey = EditedKey()
+        }
+    }
+    
+    var isValid: Bool {
+        editedKey.toTOTPKey() != nil
+    }
+    
+    var body: some View {
+        Form {
+            TextField("Issuer", text: $editedKey.issuer)
+                .focused($issuerFocused)
+            TextField("Account", text: $editedKey.label)
+                .disableAutocorrection(true)
+                .autocapitalization(.none)
+            
+            HStack {
+                TextField("Secret", text: $editedKey.secret)
+                Button {
+                    self.editedKey.secret = UIPasteboard.general.string ?? ""
+                } label: {
+                    Label("Paste", systemImage: "doc.on.clipboard")
+                        .labelStyle(.iconOnly)
+                        .foregroundColor(.accentColor)
+                }
+                .buttonStyle(.plain)
+                .disabled(!UIPasteboard.general.hasStrings)
+            }
+            
+            HStack {
+                Text("Period")
+                Spacer()
+                Picker("Period", selection: $editedKey.period) {
+                    Text("30 sec").tag(EditedKey.Period.thirty)
+                    Text("60 sec").tag(EditedKey.Period.sixty)
+                }
+                .pickerStyle(.segmented)
+                .frame(maxWidth: 200)
+            }
+            
+            HStack {
+                Text("Digits")
+                Spacer()
+                Picker("Digits", selection: $editedKey.digits) {
+                    Text("6").tag(EditedKey.Digits.six)
+                    Text("8").tag(EditedKey.Digits.eight)
+                }
+                .pickerStyle(.segmented)
+                .frame(maxWidth: 200)
+            }
+        }
+        .onAppear {
+            if focusOnAppear {
+                // todo: this just doesn't work :/
+                // https://developer.apple.com/forums/thread/681962
+                // FB9551099
+                issuerFocused = true
+            }
+        }
+        .onSubmit {
+            if isValid {
+                dismiss(.save(editedKey.toTOTPKey()!))
+            }
+        }
+        .toolbar {
+            ToolbarItem(placement: .navigationBarLeading) {
+                // ToolbarContentBuilder doesn't support conditionals, so this has to go inside the ToolbarItem
+                if showCancelButton {
+                    Button("Cancel") {
+                        dismiss(.cancel)
+                    }
+                }
+            }
+            ToolbarItem(placement: .navigationBarTrailing) {
+                Button("Save") {
+                    dismiss(.save(editedKey.toTOTPKey()!))
+                }
+                .disabled(!isValid)
+            }
+        }
+    }
+}
+
+struct EditKeyForm_Previews: PreviewProvider {
+    static var previews: some View {
+        EditKeyForm(editingKey: nil) { (_) in }
+    }
+}

OTP/Views/FolderRow.swift

@@ -0,0 +1,80 @@
+//
+//  FolderRow.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/24/21.
+//
+
+import SwiftUI
+
+struct FolderRow: View {
+    @ObservedObject private var store: KeyStore
+    @State private var folder: KeyData.Folder
+    @State private var editing = false
+    @FocusState private var focused: Bool
+    @State private var isTargetedForDrop = false
+    
+    init(store: KeyStore, folder: KeyData.Folder) {
+        self.store = store
+        self._folder = State(initialValue: folder)
+    }
+    
+    var body: some View {
+        NavigationLink {
+            FolderView(folder: folder)
+        } label: {
+            HStack {
+                Image(systemName: "folder.fill")
+                    .foregroundColor(.accentColor)
+                
+                if editing {
+                    TextField("Name", text: $folder.name)
+                        .focused($focused)
+                        .submitLabel(.done)
+                        .onSubmit {
+                            withAnimation {
+                                store.updateFolder(folder)
+                            }
+                            editing = false
+                            focused = false
+                        }
+                } else {
+                    Text(folder.name)
+                }
+            }
+//            .background(isTargetedForDrop ? Color.red : nil)
+//            .onDrop(of: [.text], isTargeted: $isTargetedForDrop) { (itemProviders) in
+//                guard let provider = itemProviders.first,
+//                      provider.canLoadObject(ofClass: NSString.self) else {
+//                          return false
+//                      }
+//                provider.loadObject(ofClass: NSString.self) { (idString, error) in
+//                    guard error == nil,
+//                          let idString = idString as? NSString,
+//                          let id = UUID(uuidString: idString as String) else {
+//                              return
+//                          }
+//                    store.moveEntryToFolder(entryID: id, folderID: folder.id)
+//                }
+//                return true
+//            }
+        }
+        .contextMenu {
+            Button {
+                editing = true
+                // just waiting 1 runloop iteration does not work for some reason :/
+                DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+                    focused = true
+                }
+            } label: {
+                Label("Rename Folder", systemImage: "pencil")
+            }
+        }
+    }
+}
+
+struct FolderRow_Previews: PreviewProvider {
+    static var previews: some View {
+        FolderRow(store: .shared, folder: .init(name: "Test"))
+    }
+}

OTP/Views/FolderView.swift

@@ -0,0 +1,37 @@
+//
+//  FolderView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/24/21.
+//
+
+import SwiftUI
+
+struct FolderView: View {
+    @ObservedObject private var store: KeyStore
+    private let folder: KeyData.Folder
+    @ObservedObject private var codeHolder: AppView.CodeHolder
+    
+    init(folder: KeyData.Folder) {
+        let store = KeyStore.shared
+        self.store = store
+        self.folder = folder
+        self.codeHolder = AppView.CodeHolder(store: store) { (entry) in
+            entry.folderID == folder.id
+        }
+    }
+    
+    var body: some View {
+        List {
+            KeysSection(codeHolder: codeHolder)
+        }
+        .listStyle(.insetGrouped)
+        .navigationTitle(folder.name)
+    }
+}
+
+struct FolderView_Previews: PreviewProvider {
+    static var previews: some View {
+        FolderView(folder: .init(name: "Test"))
+    }
+}

OTP/Views/FoldersSection.swift

@@ -0,0 +1,33 @@
+//
+//  FoldersSection.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/24/21.
+//
+
+import SwiftUI
+
+struct FoldersSection: View {
+    @ObservedObject private var store: KeyStore = .shared
+    @FocusState private var focusedEdited: Bool
+    
+    var body: some View {
+        Section {
+            ForEach(store.sortedFolders) { (folder) in
+                FolderRow(store: store, folder: folder)
+            }
+            .onDelete { (indices) in
+                let folderIDs = indices.map { store.sortedFolders[$0].id }
+                withAnimation {
+                    folderIDs.forEach(store.removeFolder(id:))
+                }
+            }
+        }
+    }
+}
+
+struct FoldersSectionView_Previews: PreviewProvider {
+    static var previews: some View {
+        FoldersSection()
+    }
+}

OTP/Views/KeyView.swift

@@ -0,0 +1,77 @@
+//
+//  KeyView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import SwiftUI
+import OTPKit
+
+struct KeyView: View {
+    let key: TOTPKey
+    let currentCode: TOTPCode
+    
+    var formattedCode: String {
+        let code = currentCode.code
+        let mid = code.index(code.startIndex, offsetBy: code.count / 2)
+        return "\(code[code.startIndex..<mid]) \(code[mid...])"
+    }
+    
+    init(key: TOTPKey, currentCode: TOTPCode) {
+        self.key = key
+        self.currentCode = currentCode
+    }
+    
+    var body: some View {
+        HStack {
+            VStack(alignment: .leading) {
+                Text(key.issuer)
+                    .font(.title3)
+                
+                if let label = key.label, !label.isEmpty {
+                    Text(label)
+                        .font(.footnote)
+                }
+            }
+            
+            Spacer()
+            
+            Text(formattedCode)
+                .font(.system(.title2, design: .monospaced))
+            
+//            Text("\(currentCode.validUntil, style: .relative)")
+//                .font(.body.monospacedDigit())
+            
+            // I don't think this TimelineView should be necessary since the CodeHolder timer fires every .5 seconds
+            TimelineView(.animation) { (ctx) in
+                ZStack {
+                    CircularProgressView(progress: progress(at: Date()), colorChangeThreshold: 5.0 / Double(key.period))
+                    
+                    Text(Int(round(currentCode.validUntil.timeIntervalSinceNow)).description)
+                        .font(.caption.monospacedDigit())
+                }
+                .frame(width: 30)
+            }
+            
+        }
+    }
+    
+    private func progress(at date: Date) -> Double {
+        let seconds = round(date.timeIntervalSince(currentCode.validFrom))
+        let progress = 1 - seconds / Double(key.period)
+        return progress
+    }
+}
+
+struct KeyView_Previews: PreviewProvider {
+    static var key: TOTPKey {
+        TOTPKey(urlComponents: URLComponents(string: "otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&issuer=Example")!)!
+    }
+    static var code: TOTPCode {
+        OTPGenerator.generate(key: key)
+    }
+    static var previews: some View {
+        KeyView(key: key, currentCode: code)
+    }
+}

OTP/Views/KeysSection.swift

@@ -0,0 +1,141 @@
+//
+//  KeysSection.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/24/21.
+//
+
+import SwiftUI
+import UniformTypeIdentifiers
+
+struct KeysSection: View {
+    @ObservedObject private var store: KeyStore = .shared
+    @ObservedObject private var entryHolder: AppView.CodeHolder
+    @State private var editedEntry: AppView.CodeEntry? = nil
+    @State private var presentedQRCode: AppView.CodeEntry? = nil
+    
+    init(codeHolder: AppView.CodeHolder) {
+        self.entryHolder = codeHolder
+    }
+    
+    var body: some View {
+        Section {
+            ForEach(entryHolder.sortedEntries) { (entry) in
+                KeyView(key: entry.key, currentCode: entry.code)
+                // disabled because dropping onto list rows does not work :/
+//                    .onDrag {
+//                        NSItemProvider(object: entry.id.uuidString as NSString)
+//                    }
+                    .contextMenu {
+                        self.keyMenu(entry: entry)
+                    }
+            }
+            .onDelete { (indices) in
+                withAnimation(.default) {
+                    for index in indices {
+                        store.removeKey(entryID: entryHolder.sortedEntries[index].id)
+                    }
+                }
+            }
+        }
+        .sheet(item: $editedEntry, content: self.editFormSheet)
+        .sheet(item: $presentedQRCode, content: self.qrCodeSheet)
+    }
+    
+    @ViewBuilder
+    private func keyMenu(entry: AppView.CodeEntry) -> some View {
+        Section {
+            Menu {
+                Button("No Folder") {
+                    withAnimation {
+                        store.moveEntryToFolder(entryID: entry.id, folderID: nil)
+                    }
+                }
+                .disabled(entry.entry.folderID == nil)
+                
+                Section {
+                    ForEach(store.sortedFolders) { (folder) in
+                        Button {
+                            withAnimation {
+                                store.moveEntryToFolder(entryID: entry.id, folderID: folder.id)
+                            }
+                        } label: {
+                            Text(folder.name)
+                        }
+                        .disabled(entry.entry.folderID == folder.id)
+                    }
+                }
+            } label: {
+                Label("Move to Folder", systemImage: "folder")
+            }
+            
+            Button {
+                // even the .contextMenu closure is called again, SwiftUI seems not to update the actual context menu buttons
+                // so when this closure is called, it's copy of entry may be stale if the entry's since been edited
+                // so we lookup the known current one by ID and edit that
+                let realEntry = entryHolder.entries.first { $0.id == entry.id }
+                editedEntry = realEntry
+            } label: {
+                Label("Edit Key", systemImage: "pencil")
+            }
+            
+            // todo: can't mark menu as destructive
+            Menu {
+                Button("Cancel", role: .cancel) {}
+                
+                Button("Delete Key", role: .destructive) {
+                    // todo: why doesn't this animation work?
+                    withAnimation(.default) {
+                        store.removeKey(entryID: entry.id)
+                    }
+                }
+            } label: {
+                Label("Delete Key", systemImage: "trash")
+            }
+        }
+        
+        Section {
+            Button {
+                let realEntry = entryHolder.entries.first { $0.id == entry.id }
+                presentedQRCode = realEntry
+            } label: {
+                Label("Export as QR", systemImage: "qrcode")
+            }
+            
+            Button {
+                UIPasteboard.general.url = entry.key.url
+            } label: {
+                Label("Copy as URL", systemImage: "link")
+            }
+        }
+    }
+    
+    private func editFormSheet(editedEntry: AppView.CodeEntry) -> some View {
+        NavigationView {
+            EditKeyForm(editingKey: editedEntry.key) { (action) in
+                self.editedEntry = nil
+                switch action {
+                case .cancel:
+                    break
+                case .save(let key):
+                    store.updateKey(entryID: editedEntry.id, newKey: key)
+                }
+            }
+            .navigationTitle("Edit Key")
+        }
+    }
+    
+    private func qrCodeSheet(entry: AppView.CodeEntry) -> some View {
+        NavigationView {
+            QRCodeView(key: entry.key)
+                .id(entry.id)
+        }
+    }
+    
+}
+
+struct KeysSection_Previews: PreviewProvider {
+    static var previews: some View {
+        KeysSection(codeHolder: .init(store: .shared))
+    }
+}

OTP/Views/PreferencesView.swift

@@ -0,0 +1,79 @@
+//
+//  PreferencesView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/23/21.
+//
+
+import SwiftUI
+
+struct PreferencesView: View {
+    @ObservedObject private var store = KeyStore.shared
+    @Environment(\.dismiss) private var dismiss
+    @State private var clearBeforeImport = false
+    @State private var isPresentingExport = false
+    @State private var isPresentingImportMode = false
+    @State private var isPresentingImport = false
+    @State private var isPresentingImportFailedAlert = false
+    @State private var importFailedError: Error? = nil
+    
+    var body: some View {
+        List {
+            Section("Backup") {
+                Button("Export to File...") {
+                    isPresentingExport = true
+                }
+                Menu("Import from File...") {
+                    Button("Keep Existing Keys") {
+                        clearBeforeImport = false
+                        isPresentingImport = true
+                    }
+                    Button("Replace Existing Keys", role: .destructive) {
+                        clearBeforeImport = true
+                        isPresentingImport = true
+                    }
+                }
+            }
+        }
+        .navigationTitle("Preferences")
+        .toolbar {
+            ToolbarItem(placement: .navigationBarTrailing) {
+                Button("Done") {
+                    dismiss()
+                }
+            }
+        }
+        .fileExporter(isPresented: $isPresentingExport, document: BackupDocument(data: store.data), contentType: .propertyList, defaultFilename: "OTPBackup") { (_) in
+        }
+        .fileImporter(isPresented: $isPresentingImport, allowedContentTypes: [.propertyList], allowsMultipleSelection: false) { (result) in
+            switch result {
+            case let .failure(error):
+                self.importFailedError = error
+                self.isPresentingImportFailedAlert = true
+            case let .success(urls):
+                do {
+                    let backup = try BackupDocument(url: urls.first!)
+                    store.updateFromStore(backup.data, replaceExisting: clearBeforeImport)
+                    dismiss()
+                } catch {
+                    self.importFailedError = error
+                    self.isPresentingImportFailedAlert = true
+                }
+            }
+        }
+        .alert("Import Failed", isPresented: $isPresentingImportFailedAlert) {
+            Button("OK", role: .cancel) {}
+        } message: {
+            if let error = importFailedError {
+                Text(error.localizedDescription)
+            }
+        }
+    }
+    
+}
+
+struct PreferencesView_Previews: PreviewProvider {
+    static var previews: some View {
+        PreferencesView()
+    }
+}

OTP/Views/QRCodeView.swift

@@ -0,0 +1,169 @@
+//
+//  QRCodeView.swift
+//  OTP
+//
+//  Created by Shadowfacts on 8/23/21.
+//
+
+import SwiftUI
+import OTPKit
+import CoreImage.CIFilterBuiltins
+
+struct QRCodeView: View {
+    let key: TOTPKey
+    @State private var image: UIImage?
+    @Environment(\.dismiss) private var dismiss
+    @State private var isPresentingShareSheet = false
+    
+    init(key: TOTPKey) {
+        self.key = key
+//        self._image = State(initialValue: createImage())
+    }
+    
+    private func createImage() -> UIImage? {
+        let filter = CIFilter.qrCodeGenerator()
+        filter.message = key.url.absoluteString.data(using: .utf8)!
+        let transform = CGAffineTransform(scaleX: 5, y: 5)
+        
+        let context = CIContext()
+        guard let output = filter.outputImage?.transformed(by: transform),
+           let cgImage = context.createCGImage(output, from: output.extent) else {
+            return nil
+        }
+        
+        let issuerFont = UIFont(descriptor: .preferredFontDescriptor(withTextStyle: .largeTitle).withSymbolicTraits(.traitBold)!, size: 0)
+        let labelFont = UIFont(descriptor: .preferredFontDescriptor(withTextStyle: .body), size: 0)
+        
+        let paragraphStyle = NSMutableParagraphStyle()
+        paragraphStyle.lineBreakMode = .byWordWrapping
+        
+        let issuer = key.issuer as NSString
+        let size = CGSize(width: CGFloat(cgImage.width - 8), height: .greatestFiniteMagnitude)
+        
+        var issuerRect = issuer.boundingRect(with: size, options: [.usesFontLeading, .usesLineFragmentOrigin], attributes: [.font: issuerFont, .paragraphStyle: paragraphStyle], context: nil)
+        issuerRect.origin.y += 4
+        issuerRect.origin.x += 4
+        
+        var labelRect = CGRect.zero
+        if let label = key.label, !label.isEmpty {
+            labelRect = (label as NSString).boundingRect(with: size, options: [.usesFontLeading, .usesLineFragmentOrigin], attributes: [.font:  labelFont, .paragraphStyle: paragraphStyle], context: nil)
+            labelRect.origin.x += 4
+            labelRect.origin.y += ceil(issuerRect.maxY)
+        }
+        
+        let imageSize = CGSize(width: CGFloat(cgImage.width), height: CGFloat(cgImage.height) + ceil(issuerRect.height) + ceil(labelRect.height) + 4)
+        let renderer = UIGraphicsImageRenderer(size: imageSize)
+        return renderer.image { (ctx) in
+            ctx.cgContext.setFillColor(UIColor.white.cgColor)
+            ctx.cgContext.fill(CGRect(origin: .zero, size: imageSize))
+            
+            issuer.draw(in: issuerRect, withAttributes: [.font: issuerFont, .paragraphStyle: paragraphStyle])
+            
+            if let label = key.label {
+                (label as NSString).draw(in: labelRect, withAttributes: [.font: labelFont, .paragraphStyle: paragraphStyle])
+            }
+            
+            let imageRect = CGRect(x: 0, y: imageSize.height - CGFloat(cgImage.height), width: CGFloat(cgImage.width), height: CGFloat(cgImage.height))
+            ctx.cgContext.draw(cgImage, in: imageRect)
+        }
+    }
+    
+    var body: some View {
+        return mainView
+            .navigationTitle("Export QR Code")
+            .toolbar {
+                ToolbarItem(placement: .navigationBarTrailing) {
+                    Button("Done") {
+                        dismiss()
+                    }
+                }
+            }
+            .background {
+                ActivityView(isPresented: $isPresentingShareSheet, items: [image as Any, key.url])
+            }
+            .task {
+                self.image = createImage()
+            }
+    }
+    
+    @ViewBuilder
+    private var mainView: some View {
+        if let image = image {
+            VStack(alignment: .center) {
+                Image(uiImage: image)
+                    .cornerRadius(5)
+                    .shadow(radius: 3)
+                
+                HStack {
+                    Button {
+                        isPresentingShareSheet = true
+                    } label: {
+                        Label("Share", systemImage: "square.and.arrow.up")
+                    }
+                    Spacer()
+                    Button(action: save) {
+                        Label("Save", systemImage: "square.and.arrow.down")
+                    }
+                }
+            }
+            // fix the size so that the HStack doesn't grow beyond with width of the image
+            .fixedSize()
+        } else {
+            ProgressView()
+                .progressViewStyle(.circular)
+        }
+    }
+    
+    private func save() {
+        guard let image = image else { return }
+        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
+    }
+}
+
+struct ActivityView: UIViewControllerRepresentable {
+    var isPresented: Binding<Bool>
+    let items: [Any]
+    
+    func makeUIViewController(context: Context) -> Wrapper {
+        return Wrapper(isPresented: isPresented, items: items)
+    }
+    
+    func updateUIViewController(_ uiViewController: Wrapper, context: Context) {
+        uiViewController.update(isPresented: isPresented, items: items)
+    }
+    
+    class Wrapper: UIViewController {
+        private(set) var isPresented: Binding<Bool>!
+        private(set) var items: [Any]!
+        
+        init(isPresented: Binding<Bool>, items: [Any]) {
+            self.isPresented = isPresented
+            self.items = items
+            
+            super.init(nibName: nil, bundle: nil)
+        }
+        
+        required init?(coder: NSCoder) {
+            fatalError("init(coder:) has not been implemented")
+        }
+        
+        func update(isPresented: Binding<Bool>, items: [Any]) {
+            self.isPresented = isPresented
+            self.items = items
+            
+            if isPresented.wrappedValue, presentedViewController == nil {
+                let vc = UIActivityViewController(activityItems: items, applicationActivities: nil)
+                vc.completionWithItemsHandler = { (_, _, _, _) in
+                    isPresented.wrappedValue = false
+                }
+                present(vc, animated: true)
+            }
+        }
+    }
+}
+
+struct QRCodeView_Previews: PreviewProvider {
+    static var previews: some View {
+        QRCodeView(key: TOTPKey(urlComponents: URLComponents(string: "otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&issuer=Example")!)!)
+    }
+}

OTPKit/OTPAlgorithm.swift

@@ -0,0 +1,12 @@
+//
+//  OTPAlgorithm.swift
+//  OTPKit
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import Foundation
+
+public enum OTPAlgorithm: Codable {
+    case SHA1
+}

OTPKit/OTPGenerator.swift

@@ -0,0 +1,45 @@
+//
+//  OTPGenerator.swift
+//  OTPKit
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import Foundation
+import CryptoKit
+
+public struct OTPGenerator {
+    
+    private init() {}
+    
+    public static func generate(key: OTPKey, counter: Int64) -> String {
+        let data = withUnsafeBytes(of: counter.bigEndian) {
+            Data($0)
+        }
+        
+        let mac = HMAC<Insecure.SHA1>.authenticationCode(for: data, using: SymmetricKey(data: key.secret))
+        
+        let uint32Code = mac.withUnsafeBytes { (ptr) -> UInt32 in
+            let offset = Int(ptr.last! & 0x0F)
+            let offsetPtr = ptr.baseAddress!.advanced(by: offset)
+            return offsetPtr.assumingMemoryBound(to: UInt32.self).pointee.bigEndian & 0x7FFFFFFF
+        }
+        
+        let truncated = uint32Code % UInt32(pow(10, Double(key.digits)))
+        
+        var s = truncated.description
+        if s.count < key.digits {
+            s = String(repeating: "0", count: key.digits - s.count) + s
+        }
+        return s
+    }
+    
+    public static func generate(key: TOTPKey) -> TOTPCode {
+        let now = Date()
+        let counter = Int64(now.timeIntervalSince1970 / Double(key.period))
+        let start = Date(timeIntervalSince1970: Double(counter * Int64(key.period)))
+        let code = generate(key: key, counter: counter)
+        return TOTPCode(code: code, validFrom: start, validInterval: key.period)
+    }
+    
+}

OTPKit/OTPKey.swift

@@ -0,0 +1,15 @@
+//
+//  OTPKey.swift
+//  OTPKit
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import Foundation
+
+public protocol OTPKey {
+    var secret: Data { get }
+    var digits: Int { get }
+    var algorithm: OTPAlgorithm { get }
+    var period: Int { get }
+}

OTPKit/OTPKit.docc/OTPKit.md

@@ -0,0 +1,13 @@
+# ``OTPKit``
+
+<!--@START_MENU_TOKEN@-->Summary<!--@END_MENU_TOKEN@-->
+
+## Overview
+
+<!--@START_MENU_TOKEN@-->Text<!--@END_MENU_TOKEN@-->
+
+## Topics
+
+### <!--@START_MENU_TOKEN@-->Group<!--@END_MENU_TOKEN@-->
+
+- <!--@START_MENU_TOKEN@-->``Symbol``<!--@END_MENU_TOKEN@-->

OTPKit/OTPKit.h

@@ -0,0 +1,18 @@
+//
+//  OTPKit.h
+//  OTPKit
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+#import <Foundation/Foundation.h>
+
+//! Project version number for OTPKit.
+FOUNDATION_EXPORT double OTPKitVersionNumber;
+
+//! Project version string for OTPKit.
+FOUNDATION_EXPORT const unsigned char OTPKitVersionString[];
+
+// In this header, you should import all the public headers of your framework using statements like #import <OTPKit/PublicHeader.h>
+
+

OTPKit/TOTPCode.swift

@@ -0,0 +1,17 @@
+//
+//  TOTPCode.swift
+//  OTPKit
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import Foundation
+
+public struct TOTPCode: Equatable, Hashable {
+    public let code: String
+    public let validFrom: Date
+    public let validInterval: Int // seconds
+    public var validUntil: Date {
+        validFrom.addingTimeInterval(TimeInterval(validInterval))
+    }
+}

OTPKit/TOTPKey.swift

@@ -0,0 +1,110 @@
+//
+//  TOTPKey.swift
+//  OTPKit
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import Foundation
+
+public struct TOTPKey: OTPKey, Equatable, Hashable, Codable {
+    public let secret: Data
+    public let period: Int
+    public let digits: Int
+    public let algorithm: OTPAlgorithm
+    public let label: String?
+    public let issuer: String
+//    let image: Data?
+    
+    public init(secret: Data, period: Int, digits: Int, label: String?, issuer: String) {
+        self.secret = secret
+        self.period = period
+        self.digits = digits
+        self.algorithm = .SHA1
+        self.label = label
+        self.issuer = issuer
+    }
+}
+
+public extension TOTPKey {
+    
+    init?(urlComponents: URLComponents) {
+        guard urlComponents.scheme == "otpauth",
+              urlComponents.host == "totp",
+              let queryItems = urlComponents.queryItems else {
+            return nil
+        }
+        
+        var label: String?
+        var issuer: String
+        var secret: Data?
+        var period: Int = 30
+        var digits = 6
+        
+        let path = urlComponents.path.drop(while: { $0 == "/" })
+        let components = path.components(separatedBy: ":")
+        if components.count > 1 {
+            issuer = components[0]
+            label = components[1]
+        } else {
+            issuer = components[0]
+        }
+        
+        for item in queryItems {
+            guard let value = item.value else { continue }
+            switch item.name.lowercased() {
+            case "algorithm":
+                if value.lowercased() != "sha1" {
+                    return  nil
+                }
+            case "digits":
+                if let newDigits = Int(value) {
+                    digits = newDigits
+                }
+            case "issuer":
+                issuer = value
+            case "period":
+                if let newPeriod = Int(value) {
+                    period = newPeriod
+                }
+            case "secret":
+                if let data = value.base32DecodedData {
+                    secret = data
+                }
+            default:
+                continue
+            }
+        }
+        
+        guard let secret = secret else { return nil }
+        self.issuer = issuer
+        self.label = label
+        self.secret = secret
+        self.period = period
+        self.digits = digits
+        self.algorithm = .SHA1
+    }
+    
+    var url: URL {
+        var components = URLComponents()
+        
+        components.scheme = "otpauth"
+        components.host = "totp"
+        
+        if let label = label, !label.isEmpty {
+            components.path = "/\(issuer):\(label)"
+        } else {
+            components.path = "/\(issuer)"
+        }
+        components.queryItems = [
+            URLQueryItem(name: "algorithm", value: "SHA1"),
+            URLQueryItem(name: "digits", value: digits.description),
+            URLQueryItem(name: "issuer", value: issuer),
+            URLQueryItem(name: "period", value: period.description),
+            URLQueryItem(name: "secret", value: secret.base32EncodedString),
+        ]
+        
+        return components.url!
+    }
+    
+}

OTPKit/Vendor/Base32.swift

@@ -0,0 +1,399 @@
+//
+//  Base32.swift
+//  TOTP
+//
+//  Created by 野村 憲男 on 1/24/15.
+//
+//  Copyright (c) 2015 Norio Nomura
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in
+//  all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+//  THE SOFTWARE.
+
+import Foundation
+
+// https://tools.ietf.org/html/rfc4648
+
+// MARK: - Base32 Data <-> String
+
+public func base32Encode(_ data: Data) -> String {
+    return data.withUnsafeBytes {
+        base32encode($0.baseAddress!, $0.count, alphabetEncodeTable)
+    }
+}
+
+public func base32HexEncode(_ data: Data) -> String {
+    return data.withUnsafeBytes {
+        base32encode($0.baseAddress!, $0.count, extendedHexAlphabetEncodeTable)
+    }
+}
+
+public func base32DecodeToData(_ string: String) -> Data? {
+    return base32decode(string, alphabetDecodeTable).flatMap(Data.init(_:))
+}
+
+public func base32HexDecodeToData(_ string: String) -> Data? {
+    return base32decode(string, extendedHexAlphabetDecodeTable).flatMap(Data.init(_:))
+}
+
+// MARK: - Base32 [UInt8] <-> String
+
+public func base32Encode(_ array: [UInt8]) -> String {
+    return base32encode(array, array.count, alphabetEncodeTable)
+}
+
+public func base32HexEncode(_ array: [UInt8]) -> String {
+    return base32encode(array, array.count, extendedHexAlphabetEncodeTable)
+}
+
+public func base32Decode(_ string: String) -> [UInt8]? {
+    return base32decode(string, alphabetDecodeTable)
+}
+
+public func base32HexDecode(_ string: String) -> [UInt8]? {
+    return base32decode(string, extendedHexAlphabetDecodeTable)
+}
+
+// MARK: extensions
+
+extension String {
+    // base32
+    public var base32DecodedData: Data? {
+        return base32DecodeToData(self)
+    }
+    
+    public var base32EncodedString: String {
+        return utf8CString.withUnsafeBufferPointer {
+            base32encode($0.baseAddress!, $0.count - 1, alphabetEncodeTable)
+        }
+    }
+    
+    public func base32DecodedString(_ encoding: String.Encoding = .utf8) -> String? {
+        return base32DecodedData.flatMap {
+            String(data: $0, encoding: .utf8)
+        }
+    }
+
+    // base32Hex
+    public var base32HexDecodedData: Data? {
+        return base32HexDecodeToData(self)
+    }
+    
+    public var base32HexEncodedString: String {
+        return utf8CString.withUnsafeBufferPointer {
+            base32encode($0.baseAddress!, $0.count - 1, extendedHexAlphabetEncodeTable)
+        }
+    }
+    
+    public func base32HexDecodedString(_ encoding: String.Encoding = .utf8) -> String? {
+        return base32HexDecodedData.flatMap {
+            String(data: $0, encoding: .utf8)
+        }
+    }
+}
+
+extension Data {
+    // base32
+    public var base32EncodedString: String {
+        return base32Encode(self)
+    }
+    
+    public var base32EncodedData: Data {
+        return base32EncodedString.dataUsingUTF8StringEncoding
+    }
+    
+    public var base32DecodedData: Data? {
+        return String(data: self, encoding: .utf8).flatMap(base32DecodeToData)
+    }
+
+    // base32Hex
+    public var base32HexEncodedString: String {
+        return base32HexEncode(self)
+    }
+    
+    public var base32HexEncodedData: Data {
+        return base32HexEncodedString.dataUsingUTF8StringEncoding
+    }
+    
+    public var base32HexDecodedData: Data? {
+        return String(data: self, encoding: .utf8).flatMap(base32HexDecodeToData)
+    }
+}
+
+// MARK: - private
+
+private extension String {
+    var dataUsingUTF8StringEncoding: Data {
+        return utf8CString.withUnsafeBufferPointer {
+            Data($0.dropLast().map(UInt8.init))
+        }
+    }
+}
+
+// MARK: encode
+
+private let alphabetEncodeTable: [Int8] = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z","2","3","4","5","6","7"].map { (c: UnicodeScalar) -> Int8 in Int8(c.value) }
+
+private let extendedHexAlphabetEncodeTable: [Int8] = ["0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V"].map { (c: UnicodeScalar) -> Int8 in Int8(c.value) }
+
+private func base32encode(_ data: UnsafeRawPointer, _ length: Int, _ table: [Int8]) -> String {
+    if length == 0 {
+        return ""
+    }
+    var length = length
+    
+    var bytes = data.assumingMemoryBound(to: UInt8.self)
+    
+    let resultBufferSize = Int(ceil(Double(length) / 5)) * 8 + 1    // need null termination
+    let resultBuffer = UnsafeMutablePointer<Int8>.allocate(capacity: resultBufferSize)
+    var encoded = resultBuffer
+    
+    // encode regular blocks
+    while length >= 5 {
+        encoded[0] = table[Int(bytes[0] >> 3)]
+        encoded[1] = table[Int((bytes[0] & 0b00000111) << 2 | bytes[1] >> 6)]
+        encoded[2] = table[Int((bytes[1] & 0b00111110) >> 1)]
+        encoded[3] = table[Int((bytes[1] & 0b00000001) << 4 | bytes[2] >> 4)]
+        encoded[4] = table[Int((bytes[2] & 0b00001111) << 1 | bytes[3] >> 7)]
+        encoded[5] = table[Int((bytes[3] & 0b01111100) >> 2)]
+        encoded[6] = table[Int((bytes[3] & 0b00000011) << 3 | bytes[4] >> 5)]
+        encoded[7] = table[Int((bytes[4] & 0b00011111))]
+        length -= 5
+        encoded = encoded.advanced(by: 8)
+        bytes = bytes.advanced(by: 5)
+    }
+    
+    // encode last block
+    var byte0, byte1, byte2, byte3, byte4: UInt8
+    (byte0, byte1, byte2, byte3, byte4) = (0,0,0,0,0)
+    switch length {
+    case 4:
+        byte3 = bytes[3]
+        encoded[6] = table[Int((byte3 & 0b00000011) << 3 | byte4 >> 5)]
+        encoded[5] = table[Int((byte3 & 0b01111100) >> 2)]
+        fallthrough
+    case 3:
+        byte2 = bytes[2]
+        encoded[4] = table[Int((byte2 & 0b00001111) << 1 | byte3 >> 7)]
+        fallthrough
+    case 2:
+        byte1 = bytes[1]
+        encoded[3] = table[Int((byte1 & 0b00000001) << 4 | byte2 >> 4)]
+        encoded[2] = table[Int((byte1 & 0b00111110) >> 1)]
+        fallthrough
+    case 1:
+        byte0 = bytes[0]
+        encoded[1] = table[Int((byte0 & 0b00000111) << 2 | byte1 >> 6)]
+        encoded[0] = table[Int(byte0 >> 3)]
+    default: break
+    }
+
+    // padding
+    let pad = Int8(UnicodeScalar("=").value)
+    switch length {
+    case 0:
+        encoded[0] = 0
+    case 1:
+        encoded[2] = pad
+        encoded[3] = pad
+        fallthrough
+    case 2:
+        encoded[4] = pad
+        fallthrough
+    case 3:
+        encoded[5] = pad
+        encoded[6] = pad
+        fallthrough
+    case 4:
+        encoded[7] = pad
+        fallthrough
+    default:
+        encoded[8] = 0
+        break
+    }
+    
+    // return
+    if let base32Encoded = String(validatingUTF8: resultBuffer) {
+        resultBuffer.deallocate()
+        return base32Encoded
+    } else {
+        resultBuffer.deallocate()
+        fatalError("internal error")
+    }
+}
+
+// MARK: decode
+
+private let __: UInt8 = 255
+private let alphabetDecodeTable: [UInt8] = [
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x00 - 0x0F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x10 - 0x1F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x20 - 0x2F
+    __,__,26,27, 28,29,30,31, __,__,__,__, __,__,__,__,  // 0x30 - 0x3F
+    __, 0, 1, 2,  3, 4, 5, 6,  7, 8, 9,10, 11,12,13,14,  // 0x40 - 0x4F
+    15,16,17,18, 19,20,21,22, 23,24,25,__, __,__,__,__,  // 0x50 - 0x5F
+    __, 0, 1, 2,  3, 4, 5, 6,  7, 8, 9,10, 11,12,13,14,  // 0x60 - 0x6F
+    15,16,17,18, 19,20,21,22, 23,24,25,__, __,__,__,__,  // 0x70 - 0x7F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x80 - 0x8F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x90 - 0x9F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xA0 - 0xAF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xB0 - 0xBF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xC0 - 0xCF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xD0 - 0xDF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xE0 - 0xEF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xF0 - 0xFF
+]
+
+private let extendedHexAlphabetDecodeTable: [UInt8] = [
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x00 - 0x0F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x10 - 0x1F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x20 - 0x2F
+     0, 1, 2, 3,  4, 5, 6, 7,  8, 9,__,__, __,__,__,__,  // 0x30 - 0x3F
+    __,10,11,12, 13,14,15,16, 17,18,19,20, 21,22,23,24,  // 0x40 - 0x4F
+    25,26,27,28, 29,30,31,__, __,__,__,__, __,__,__,__,  // 0x50 - 0x5F
+    __,10,11,12, 13,14,15,16, 17,18,19,20, 21,22,23,24,  // 0x60 - 0x6F
+    25,26,27,28, 29,30,31,__, __,__,__,__, __,__,__,__,  // 0x70 - 0x7F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x80 - 0x8F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0x90 - 0x9F
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xA0 - 0xAF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xB0 - 0xBF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xC0 - 0xCF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xD0 - 0xDF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xE0 - 0xEF
+    __,__,__,__, __,__,__,__, __,__,__,__, __,__,__,__,  // 0xF0 - 0xFF
+]
+
+
+private func base32decode(_ string: String, _ table: [UInt8]) -> [UInt8]? {
+    let length = string.unicodeScalars.count
+    if length == 0 {
+        return []
+    }
+    
+    // calc padding length
+    func getLeastPaddingLength(_ string: String) -> Int {
+        if string.hasSuffix("======") {
+            return 6
+        } else if string.hasSuffix("====") {
+            return 4
+        } else if string.hasSuffix("===") {
+            return 3
+        } else if string.hasSuffix("=") {
+            return 1
+        } else {
+            return 0
+        }
+    }
+    
+    // validate string
+    let leastPaddingLength = getLeastPaddingLength(string)
+    if let index = string.unicodeScalars.firstIndex(where: {$0.value > 0xff || table[Int($0.value)] > 31}) {
+        // index points padding "=" or invalid character that table does not contain.
+        let pos = string.unicodeScalars.distance(from: string.unicodeScalars.startIndex, to: index)
+        // if pos points padding "=", it's valid.
+        if pos != length - leastPaddingLength {
+            print("string contains some invalid characters.")
+            return nil
+        }
+    }
+    
+    var remainEncodedLength = length - leastPaddingLength
+    var additionalBytes = 0
+    switch remainEncodedLength % 8 {
+        // valid
+    case 0: break
+    case 2: additionalBytes = 1
+    case 4: additionalBytes = 2
+    case 5: additionalBytes = 3
+    case 7: additionalBytes = 4
+    default:
+        print("string length is invalid.")
+        return nil
+    }
+    
+    // validated
+    let dataSize = remainEncodedLength / 8 * 5 + additionalBytes
+    
+    // Use UnsafePointer<UInt8>
+    return string.utf8CString.withUnsafeBufferPointer {
+        (data: UnsafeBufferPointer<CChar>) -> [UInt8] in
+        var encoded = data.baseAddress!
+        
+        var result = Array<UInt8>(repeating: 0, count: dataSize)
+        var decodedOffset = 0
+        
+        // decode regular blocks
+        var value0, value1, value2, value3, value4, value5, value6, value7: UInt8
+        (value0, value1, value2, value3, value4, value5, value6, value7) = (0,0,0,0,0,0,0,0)
+        while remainEncodedLength >= 8 {
+            value0 = table[Int(encoded[0])]
+            value1 = table[Int(encoded[1])]
+            value2 = table[Int(encoded[2])]
+            value3 = table[Int(encoded[3])]
+            value4 = table[Int(encoded[4])]
+            value5 = table[Int(encoded[5])]
+            value6 = table[Int(encoded[6])]
+            value7 = table[Int(encoded[7])]
+            
+            result[decodedOffset]     = value0 << 3 | value1 >> 2
+            result[decodedOffset + 1] = value1 << 6 | value2 << 1 | value3 >> 4
+            result[decodedOffset + 2] = value3 << 4 | value4 >> 1
+            result[decodedOffset + 3] = value4 << 7 | value5 << 2 | value6 >> 3
+            result[decodedOffset + 4] = value6 << 5 | value7
+            
+            remainEncodedLength -= 8
+            decodedOffset += 5
+            encoded = encoded.advanced(by: 8)
+        }
+        
+        // decode last block
+        (value0, value1, value2, value3, value4, value5, value6, value7) = (0,0,0,0,0,0,0,0)
+        switch remainEncodedLength {
+        case 7:
+            value6 = table[Int(encoded[6])]
+            value5 = table[Int(encoded[5])]
+            fallthrough
+        case 5:
+            value4 = table[Int(encoded[4])]
+            fallthrough
+        case 4:
+            value3 = table[Int(encoded[3])]
+            value2 = table[Int(encoded[2])]
+            fallthrough
+        case 2:
+            value1 = table[Int(encoded[1])]
+            value0 = table[Int(encoded[0])]
+        default: break
+        }
+        switch remainEncodedLength {
+        case 7:
+            result[decodedOffset + 3] = value4 << 7 | value5 << 2 | value6 >> 3
+            fallthrough
+        case 5:
+            result[decodedOffset + 2] = value3 << 4 | value4 >> 1
+            fallthrough
+        case 4:
+            result[decodedOffset + 1] = value1 << 6 | value2 << 1 | value3 >> 4
+            fallthrough
+        case 2:
+            result[decodedOffset]     = value0 << 3 | value1 >> 2
+        default: break
+        }
+
+        return result
+    }
+}

OTPKitTests/OTPGeneratorTests.swift

@@ -0,0 +1,25 @@
+//
+//  OTPGeneratorTests.swift
+//  OTPKitTests
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import XCTest
+@testable import OTPKit
+
+class OTPGeneratorTests: XCTestCase {
+
+    func testGenerateTOTP() {
+        let key = TOTPKey(urlComponents: URLComponents(string: "otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&issuer=Example")!)!
+        let result = OTPGenerator.generate(key: key, counter: 54319307)
+        XCTAssertEqual(result, "155456")
+    }
+    
+    func testPadWithZeroes() {
+        let key = TOTPKey(urlComponents: URLComponents(string: "otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&issuer=Example")!)!
+        let result = OTPGenerator.generate(key: key, counter: 54319378)
+        XCTAssertEqual(result, "095891")
+    }
+
+}

OTPKitTests/OTPKitTests.swift

@@ -0,0 +1,33 @@
+//
+//  OTPKitTests.swift
+//  OTPKitTests
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import XCTest
+@testable import OTPKit
+
+class OTPKitTests: XCTestCase {
+
+    override func setUpWithError() throws {
+        // Put setup code here. This method is called before the invocation of each test method in the class.
+    }
+
+    override func tearDownWithError() throws {
+        // Put teardown code here. This method is called after the invocation of each test method in the class.
+    }
+
+    func testExample() throws {
+        // This is an example of a functional test case.
+        // Use XCTAssert and related functions to verify your tests produce the correct results.
+    }
+
+    func testPerformanceExample() throws {
+        // This is an example of a performance test case.
+        self.measure {
+            // Put the code you want to measure the time of here.
+        }
+    }
+
+}

OTPKitTests/TOTPKeyTests.swift

@@ -0,0 +1,67 @@
+//
+//  TOTPKeyTests.swift
+//  OTPKitTests
+//
+//  Created by Shadowfacts on 8/21/21.
+//
+
+import XCTest
+@testable import OTPKit
+
+class TOTPKeyTests: XCTestCase {
+
+    func testDecodeSimpleKey() throws {
+        let decoded = TOTPKey(urlComponents: URLComponents(string: "otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&issuer=Example")!)
+        XCTAssertNotNil(decoded)
+        let key = decoded!
+        XCTAssertEqual(key.secret, Data([
+            UInt8(ascii: "H"),
+            UInt8(ascii: "e"),
+            UInt8(ascii: "l"),
+            UInt8(ascii: "l"),
+            UInt8(ascii: "o"),
+            UInt8(ascii: "!"),
+            0xDE, 0xAD, 0xBE, 0xEF
+        ]))
+        XCTAssertEqual(key.issuer, "Example")
+        XCTAssertEqual(key.label, "alice@google.com")
+    }
+    
+    func testDecodeOptionalParameters() throws {
+        let decoded = TOTPKey(urlComponents: URLComponents(string: "otpauth://totp/ACME%20Co:john.doe@email.com?secret=HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ&issuer=ACME%20Co&algorithm=SHA1&digits=8&period=60")!)
+        XCTAssertNotNil(decoded)
+        let key = decoded!
+        XCTAssertEqual(key.secret, Data([
+            0x3D, 0xC6, 0xCA, 0xA4,
+            0x82, 0x4A, 0x6D, 0x28,
+            0x87, 0x67, 0xB2, 0x33,
+            0x1E, 0x20, 0xB4, 0x31,
+            0x66, 0xCB, 0x85, 0xD9,
+        ]))
+        XCTAssertEqual(key.issuer, "ACME Co")
+        XCTAssertEqual(key.label, "john.doe@email.com")
+        XCTAssertEqual(key.period, 60)
+        XCTAssertEqual(key.digits, 8)
+    }
+    
+    func testDecodeInvalidAlgorithm() {
+        let components = URLComponents(string: "otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&algorithm=SHA256")!
+        XCTAssertNil(TOTPKey(urlComponents: components))
+    }
+    
+    func testRoundtripURL() {
+        let components = URLComponents(string: "otpauth://totp/ACME%20Co:john.doe@email.com?secret=HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ&issuer=ACME%20Co&algorithm=SHA1&digits=8&period=60")!
+        let key = TOTPKey(urlComponents: components)
+        XCTAssertNotNil(key)
+        let outputComponents = URLComponents(url: key!.url, resolvingAgainstBaseURL: false)!
+        XCTAssertEqual(outputComponents.scheme, components.scheme)
+        XCTAssertEqual(outputComponents.host, components.host)
+        XCTAssertEqual(outputComponents.path, components.path)
+        XCTAssertEqual(
+            outputComponents.queryItems!.sorted { (a, b) in a.name < b.name },
+            components.queryItems!.sorted { (a, b) in a.name < b.name }
+        )
+        
+    }
+
+}