//
//  UserActivityManager.swift
//  Tusker
//
//  Created by Shadowfacts on 10/19/18.
//  Copyright © 2018 Shadowfacts. All rights reserved.
//

import UIKit
import Intents
import Pachyderm
import OSLog

private let logger = Logger(subsystem: Bundle.main.bundleIdentifier!, category: "UserActivityManager")

class UserActivityManager {
    
    private let scene: UIWindowScene
    
    init(scene: UIWindowScene) {
        self.scene = scene
    }
    
    // MARK: - Utils
    private static let encoder = PropertyListEncoder()
    private static let decoder = PropertyListDecoder()
    
    private var mastodonController: MastodonController {
        scene.session.mastodonController!
    }
    
    private func getMainViewController() -> TuskerRootViewController {
        let window = scene.windows.first { $0.isKeyWindow } ?? scene.windows.first!
        return window.rootViewController as! TuskerRootViewController
    }
    
    private func present(_ vc: UIViewController, animated: Bool = true) {
        getMainViewController().present(vc, animated: animated)
    }
    
    static func getAccount(from activity: NSUserActivity) -> LocalData.UserAccountInfo? {
        guard let id = activity.userInfo?["accountID"] as? String else {
            return nil
        }
        return LocalData.shared.getAccount(id: id)
    }
    
    // MARK: - Main Scene
    static func mainSceneActivity(accountID: String?) -> NSUserActivity {
        let activity = NSUserActivity(type: .mainScene)
        if let accountID {
            activity.userInfo = [
                "accountID": accountID,
            ]
        }
        return activity
    }

    // MARK: - New Post
    static func newPostActivity(mentioning: Account? = nil, accountID: String) -> NSUserActivity {
        // todo: update to use managed objects
        let activity = NSUserActivity(type: .newPost)
        activity.isEligibleForPrediction = true
        activity.userInfo = [
            "accountID": accountID,
        ]
        if let mentioning = mentioning {
            activity.userInfo!["mentioning"] = mentioning.acct
            activity.title = "Send a message to \(mentioning.displayName)"
            activity.suggestedInvocationPhrase = "Send a message to \(mentioning.displayName)"
        } else {
            activity.title = "New Post"
            activity.suggestedInvocationPhrase = "Post in Tusker"
        }
        return activity
    }
    
    func handleNewPost(activity: NSUserActivity) {
        // TODO: check not currently showing compose screen
        let mentioning = activity.userInfo?["mentioning"] as? String
        let draft = mastodonController.createDraft(mentioningAcct: mentioning)
        // todo: this shouldn't use self.mastodonController, it should get the right one based on the userInfo accountID
        let composeVC = ComposeHostingController(draft: draft, mastodonController: mastodonController)
        present(UINavigationController(rootViewController: composeVC))
    }
    
    static func editDraftActivity(id: UUID, accountID: String) -> NSUserActivity {
        let activity = NSUserActivity(type: .newPost)
        activity.userInfo = [
            "accountID": accountID,
            "draftID": id.uuidString,
        ]
        return activity
    }
    
    static func addDuckedDraft(to activity: NSUserActivity?, draft: Draft) -> NSUserActivity {
        if let activity {
            activity.addUserInfoEntries(from: [
                "duckedDraftID": draft.id.uuidString
            ])
            return activity
        } else {
            return editDraftActivity(id: draft.id, accountID: draft.accountID)
        }
    }
    
    static func addEditedDraft(to activity: NSUserActivity?, draft: Draft) -> NSUserActivity {
        if let activity {
            activity.addUserInfoEntries(from: [
                "editedDraftID": draft.id.uuidString
            ])
            return activity
        } else {
            return editDraftActivity(id: draft.id, accountID: draft.accountID)
        }
    }
    
    static func getDraft(from activity: NSUserActivity) -> Draft? {
        let idStr: String?
        if activity.activityType == UserActivityType.newPost.rawValue {
            idStr = activity.userInfo?["draftID"] as? String
        } else {
            idStr = activity.userInfo?["duckedDraftID"] as? String ?? activity.userInfo?["editedDraftID"] as? String
        }
        guard let idStr,
              let uuid = UUID(uuidString: idStr) else {
            return nil
        }
        return DraftsManager.shared.getBy(id: uuid)
    }
    
    // MARK: - Check Notifications
    static func checkNotificationsActivity(mode: NotificationsMode = .allNotifications) -> NSUserActivity {
        let activity = NSUserActivity(type: .checkNotifications)
        activity.isEligibleForPrediction = true
        activity.addUserInfoEntries(from: [
            "notificationsMode": mode.rawValue
        ])
        switch mode {
        case .allNotifications:
            activity.title = NSLocalizedString("Check Notifications", comment: "check notifications shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Check my Tusker notifications", comment: "check notifications shortcut invocation phrase")
        case .mentionsOnly:
            activity.title = NSLocalizedString("Check Mentions", comment: "check mentions shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Check my mentions", comment: "check mentions shortcut invocation phrase")
        }
        return activity
    }
    
    func handleCheckNotifications(activity: NSUserActivity) {
        let mainViewController = getMainViewController()
        mainViewController.select(tab: .notifications)
        if let navigationController = mainViewController.getTabController(tab: .notifications) as? UINavigationController,
           let notificationsPageController = navigationController.viewControllers.first as? NotificationsPageViewController {
            navigationController.popToRootViewController(animated: false)
            notificationsPageController.loadViewIfNeeded()
            notificationsPageController.selectMode(Self.getNotificationsMode(from: activity) ?? Preferences.shared.defaultNotificationsMode)
        }
    }
    
    static func getNotificationsMode(from activity: NSUserActivity) -> NotificationsMode? {
        guard let str = activity.userInfo?["notificationsMode"] as? String else {
            return nil
        }
        return NotificationsMode(rawValue: str)
    }
    
    // MARK: - Show Timeline
    static func showTimelineActivity(timeline: Timeline, accountID: String) -> NSUserActivity? {
        guard let timelineData = try? encoder.encode(timeline) else { return nil }
        
        let activity = NSUserActivity(type: .showTimeline)
        activity.isEligibleForPrediction = true
        activity.userInfo = [
            "timelineData": timelineData,
            "accountID": accountID,
        ]
        switch timeline {
        case .home:
            activity.title = NSLocalizedString("Show Home Timeline", comment: "home timeline shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Show my home timeline", comment: "home timeline shortcut invocation phrase")
        case  .public(local: true):
            activity.title = NSLocalizedString("Show Local Timeline", comment: "local timeline shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Show my local timeline", comment: "local timeline shortcut invocation phrase")
        case .public(local: false):
            activity.title = NSLocalizedString("Show Federated Timeline", comment: "federated timeline shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Show my federated timeline", comment: "federated timeline invocation phrase")
        case let .tag(hashtag):
            activity.title = String(format: NSLocalizedString("Show #%@", comment: "show hashtag shortcut title"), hashtag)
            activity.suggestedInvocationPhrase = String(format: NSLocalizedString("Show the %@ hashtag", comment: "hashtag shortcut invocation phrase"), hashtag)
        case .list:
            // todo: add title to list
            activity.title = NSLocalizedString("Show List", comment: "list timeline shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Show my list", comment: "list timeline invocation phrase")
        case .direct:
            activity.title = NSLocalizedString("Show Direct Messages", comment: "direct message timeline shortcut title")
            activity.suggestedInvocationPhrase = NSLocalizedString("Show my direct messages", comment: "direct message timeline invocation phrase")
        }
        return activity
    }
    
    static func getTimeline(from activity: NSUserActivity) -> Timeline? {
        guard activity.activityType == UserActivityType.showTimeline.rawValue,
              let data = activity.userInfo?["timelineData"] as? Data else {
            return nil
        }
        return try? UserActivityManager.decoder.decode(Timeline.self, from: data)
    }
    
    func handleShowTimeline(activity: NSUserActivity) {
        guard let timeline = Self.getTimeline(from: activity) else { return }
        
        let mainViewController = getMainViewController()
        mainViewController.select(tab: .timelines)
        guard let navigationController = mainViewController.getTabController(tab: .timelines) as? UINavigationController else {
            return
        }
        
        if let pinned = PinnedTimeline(timeline: timeline),
           mastodonController.accountPreferences.pinnedTimelines.contains(pinned) {
            navigationController.popToRootViewController(animated: false)
            let rootController = navigationController.viewControllers.first! as! TimelinesPageViewController
            rootController.selectTimeline(pinned, animated: false)
        } else {
            let timeline = TimelineViewController(for: timeline, mastodonController: mastodonController)
            navigationController.pushViewController(timeline, animated: false)
        }
    }
    
    // MARK: - Show Conversation
    static func showConversationActivity(mainStatusID: String, accountID: String, isEligibleForPrediction: Bool = false) -> NSUserActivity {
        let activity = NSUserActivity(type: .showConversation)
        activity.userInfo = [
            "mainStatusID": mainStatusID,
            "accountID": accountID,
        ]
        activity.isEligibleForPrediction = isEligibleForPrediction
        return activity
    }
    
    static func getConversationStatus(from activity: NSUserActivity) -> String? {
        return activity.userInfo?["mainStatusID"] as? String
    }
    
    // MARK: - Explore

    static func searchActivity() -> NSUserActivity {
        let activity = NSUserActivity(type: .search)
        activity.isEligibleForPrediction = true
        activity.title = NSLocalizedString("Search", comment: "search shortcut title")
        activity.suggestedInvocationPhrase = NSLocalizedString("Search the fediverse", comment: "search shortcut invocation phrase")
        return activity
    }
    
    func handleSearch(activity: NSUserActivity) {
        let mainViewController = getMainViewController()
        mainViewController.select(tab: .explore)
        if let navigationController = mainViewController.getTabController(tab: .explore) as? UINavigationController,
            let exploreController = navigationController.viewControllers.first as? ExploreViewController {
            navigationController.popToRootViewController(animated: false)
            exploreController.loadViewIfNeeded()
            exploreController.searchController.isActive = true
            exploreController.searchController.searchBar.becomeFirstResponder()
        }
    }

    static func bookmarksActivity() -> NSUserActivity {
        let activity = NSUserActivity(type: .bookmarks)
        activity.isEligibleForPrediction = true
        activity.title = NSLocalizedString("View Bookmarks", comment: "bookmarks shortcut title")
        activity.suggestedInvocationPhrase = NSLocalizedString("Show my bookmarks in Tusker", comment: "bookmarks shortcut invocation phrase")
        return activity
    }
    
    func handleBookmarks(activity: NSUserActivity) {
        let mainViewController = getMainViewController()
        mainViewController.select(tab: .explore)
        if let navigationController = mainViewController.getTabController(tab: .explore) as? UINavigationController {
            navigationController.popToRootViewController(animated: false)
            navigationController.pushViewController(BookmarksTableViewController(mastodonController: mastodonController), animated: false)
        }
    }
    
    // MARK: - My Profile
    static func myProfileActivity() -> NSUserActivity {
        let activity = NSUserActivity(type: .myProfile)
        activity.isEligibleForPrediction = true
        activity.title = NSLocalizedString("My Profile", comment: "my profile shortcut title")
        activity.suggestedInvocationPhrase = NSLocalizedString("Show my Mastodon profile", comment: "my profile shortuct invocation phrase")
        return activity
    }
    
    func handleMyProfile(activity: NSUserActivity) {
        let mainViewController = getMainViewController()
        mainViewController.select(tab: .myProfile)
    }
    
    // MARK: - Show Profile
    static func showProfileActivity(id profileID: String, accountID: String) -> NSUserActivity {
        let activity = NSUserActivity(type: .showProfile)
        activity.userInfo = [
            "profileID": profileID,
            "accountID": accountID,
        ]
        // todo: should this be eligible for prediction?
        return activity
    }
    
    static func getProfile(from activity: NSUserActivity) -> String? {
        return activity.userInfo?["profileID"] as? String
    }
    
}