From df10b36a88f3ac517fb18217a750dd777139a372 Mon Sep 17 00:00:00 2001
From: Shadowfacts <me@shadowfacts.net>
Date: Fri, 14 Sep 2018 11:35:00 -0400
Subject: [PATCH] Pachyderm: Fix pagination

---
 Pachyderm/Model/Timeline.swift      | 25 ++++++++++++++-----------
 Pachyderm/Request/Parameter.swift   |  3 ++-
 Pachyderm/Request/Request.swift     | 27 ++++++++++++++++++---------
 Pachyderm/Response/Pagination.swift |  4 ++--
 4 files changed, 36 insertions(+), 23 deletions(-)

diff --git a/Pachyderm/Model/Timeline.swift b/Pachyderm/Model/Timeline.swift
index e1eb7794..ba4eb047 100644
--- a/Pachyderm/Model/Timeline.swift
+++ b/Pachyderm/Model/Timeline.swift
@@ -17,22 +17,25 @@ public enum Timeline {
 }
 
 extension Timeline {
-    func request(range: RequestRange) -> Request<[Status]> {
-        var request: Request<[Status]>
+    var endpoint: String {
         switch self {
         case .home:
-            request = Request(method: .get, path: "/api/v1/timelines/home")
-        case let .public(local):
-            request = Request(method: .get, path: "/api/v1/timelines/public")
-            if local {
-                request.queryParameters.append("local" => true)
-            }
+            return "/api/v1/timelines/home"
+        case .public:
+            return "/api/v1/timelines/public"
         case let .tag(hashtag):
-            request = Request(method: .get, path: "/api/v1/timeliens/tag/\(hashtag)")
+            return "/api/v1/timelines/tag/\(hashtag)"
         case let .list(id):
-            request = Request(method: .get, path: "/api/v1/timelines/list/\(id)")
+            return "/api/v1/timelines/list/\(id)"
         case .direct:
-            request = Request(method: .get, path: "/api/v1/timelines/direct")
+            return "/api/v1/timelines/direct"
+        }
+    }
+    
+    func request(range: RequestRange) -> Request<[Status]> {
+        var request = Request<[Status]>(method: .get, path: endpoint)
+        if case .public(true) = self {
+            request.queryParameters.append("local" => true)
         }
         request.range = range
         return request
diff --git a/Pachyderm/Request/Parameter.swift b/Pachyderm/Request/Parameter.swift
index c6362765..8c03b9a5 100644
--- a/Pachyderm/Request/Parameter.swift
+++ b/Pachyderm/Request/Parameter.swift
@@ -74,7 +74,8 @@ extension Array where Element == Parameter {
     
     var queryItems: [URLQueryItem] {
         return compactMap {
-            URLQueryItem(name: $0.name, value: $0.value)
+            guard let value = $0.value else { return nil }
+            return URLQueryItem(name: $0.name, value: value)
         }
     }
 }
diff --git a/Pachyderm/Request/Request.swift b/Pachyderm/Request/Request.swift
index c9b3a1b0..522369d3 100644
--- a/Pachyderm/Request/Request.swift
+++ b/Pachyderm/Request/Request.swift
@@ -40,17 +40,26 @@ extension Request {
         }
         set {
             let rangeParams = newValue.queryParameters
-            let max = rangeParams.first { $0.name == "max_id" }
-            let since = rangeParams.first { $0.name == "since_id" }
-            let count = rangeParams.first { $0.name == "count" }
-            if let max = max, let i = queryParameters.firstIndex(where: { $0.name == "max_id" }) {
-                queryParameters[i] = max
+            if let max = rangeParams.first(where: { $0.name == "max_id" }) {
+                if let i = queryParameters.firstIndex(where: { $0.name == "max_id" }) {
+                    queryParameters[i] = max
+                } else {
+                    queryParameters.append(max)
+                }
             }
-            if let since = since, let i = queryParameters.firstIndex(where: { $0.name == "since_id" }) {
-                queryParameters[i] = since
+            if let since = rangeParams.first(where: { $0.name == "since_id" }) {
+                if let i = queryParameters.firstIndex(where: { $0.name == "since_id" }) {
+                    queryParameters[i] = since
+                } else {
+                    queryParameters.append(since)
+                }
             }
-            if let count = count, let i = queryParameters.firstIndex(where: { $0.name == "count" }) {
-                queryParameters[i] = count
+            if let count = rangeParams.first(where: { $0.name == "count" }) {
+                if let i = queryParameters.firstIndex(where: { $0.name == "count" }) {
+                    queryParameters[i] = count
+                } else {
+                    queryParameters.append(count)
+                }
             }
         }
     }
diff --git a/Pachyderm/Response/Pagination.swift b/Pachyderm/Response/Pagination.swift
index c0ec4cec..07d86a54 100644
--- a/Pachyderm/Response/Pagination.swift
+++ b/Pachyderm/Response/Pagination.swift
@@ -30,9 +30,9 @@ extension Pagination {
         var range: RequestRange {
             switch kind {
             case .next:
-                return .after(id: id, count: limit)
-            case .prev:
                 return .before(id: id, count: limit)
+            case .prev:
+                return .after(id: id, count: limit)
             }
         }