Hello, mpv! 🎉

Model/Player/Backends/AVPlayerBackend.swift

@@ -0,0 +1,613 @@
+import AVFoundation
+import Defaults
+import Foundation
+import MediaPlayer
+import UIKit
+
+final class AVPlayerBackend: PlayerBackend {
+    static let assetKeysToLoad = ["tracks", "playable", "duration"]
+
+    var model: PlayerModel!
+    var controls: PlayerControlsModel!
+
+    var stream: Stream?
+    var video: Video?
+
+    var currentTime: CMTime? {
+        avPlayer.currentTime()
+    }
+
+    var loadedVideo: Bool {
+        !avPlayer.currentItem.isNil
+    }
+
+    var isLoadingVideo: Bool {
+        model.currentItem == nil || model.time == nil || !model.time!.isValid
+    }
+
+    var isPlaying: Bool {
+        avPlayer.timeControlStatus == .playing
+    }
+
+    var playerItemDuration: CMTime? {
+        avPlayer.currentItem?.asset.duration
+    }
+
+    private(set) var avPlayer = AVPlayer()
+    var controller: AppleAVPlayerViewController?
+
+    private var asset: AVURLAsset?
+    private var composition = AVMutableComposition()
+    private var loadedCompositionAssets = [AVMediaType]()
+
+    private var currentArtwork: MPMediaItemArtwork?
+    private var frequentTimeObserver: Any?
+    private var infrequentTimeObserver: Any?
+    private var playerTimeControlStatusObserver: Any?
+
+    private var statusObservation: NSKeyValueObservation?
+
+    private var timeObserverThrottle = Throttle(interval: 2)
+
+    init(model: PlayerModel, controls: PlayerControlsModel?) {
+        self.model = model
+        self.controls = controls
+
+        addFrequentTimeObserver()
+        addInfrequentTimeObserver()
+        addPlayerTimeControlStatusObserver()
+    }
+
+    func bestPlayable(_ streams: [Stream]) -> Stream? {
+        streams.first { $0.kind == .hls } ??
+            streams.filter { $0.kind == .adaptive }.max { $0.resolution < $1.resolution } ??
+            streams.first
+    }
+
+    func canPlay(_ stream: Stream) -> Bool {
+        stream.kind == .hls || stream.kind == .stream || stream.videoFormat == "MPEG_4" ||
+            (stream.videoFormat.starts(with: "video/mp4") && stream.encoding == "h264")
+    }
+
+    func playStream(
+        _ stream: Stream,
+        of video: Video,
+        preservingTime: Bool,
+        upgrading: Bool
+    ) {
+        if let url = stream.singleAssetURL {
+            model.logger.info("playing stream with one asset\(stream.kind == .hls ? " (HLS)" : ""): \(url)")
+            loadSingleAsset(url, stream: stream, of: video, preservingTime: preservingTime)
+        } else {
+            model.logger.info("playing stream with many assets:")
+            model.logger.info("composition audio asset: \(stream.audioAsset.url)")
+            model.logger.info("composition video asset: \(stream.videoAsset.url)")
+
+            loadComposition(stream, of: video, preservingTime: preservingTime)
+        }
+
+        if !upgrading {
+            updateCurrentArtwork()
+        }
+    }
+
+    func play() {
+        guard avPlayer.timeControlStatus != .playing else {
+            return
+        }
+
+        avPlayer.play()
+    }
+
+    func pause() {
+        guard avPlayer.timeControlStatus != .paused else {
+            return
+        }
+
+        avPlayer.pause()
+    }
+
+    func togglePlay() {
+        isPlaying ? pause() : play()
+    }
+
+    func stop() {
+        avPlayer.replaceCurrentItem(with: nil)
+    }
+
+    func seek(to time: CMTime, completionHandler: ((Bool) -> Void)?) {
+        avPlayer.seek(
+            to: time,
+            toleranceBefore: .secondsInDefaultTimescale(1),
+            toleranceAfter: .zero,
+            completionHandler: completionHandler ?? { _ in }
+        )
+    }
+
+    func seek(relative time: CMTime, completionHandler: ((Bool) -> Void)? = nil) {
+        if let currentTime = currentTime {
+            seek(to: currentTime + time, completionHandler: completionHandler)
+        }
+    }
+
+    func setRate(_ rate: Float) {
+        avPlayer.rate = rate
+    }
+
+    func closeItem() {
+        avPlayer.replaceCurrentItem(with: nil)
+    }
+
+    func enterFullScreen() {
+        controller?.playerView
+            .perform(NSSelectorFromString("enterFullScreenAnimated:completionHandler:"), with: false, with: nil)
+    }
+
+    func exitFullScreen() {
+        controller?.playerView
+            .perform(NSSelectorFromString("exitFullScreenAnimated:completionHandler:"), with: false, with: nil)
+    }
+
+    #if os(tvOS)
+        func closePiP(wasPlaying: Bool) {
+            let item = avPlayer.currentItem
+            let time = avPlayer.currentTime()
+
+            avPlayer.replaceCurrentItem(with: nil)
+
+            guard !item.isNil else {
+                return
+            }
+
+            avPlayer.seek(to: time)
+            avPlayer.replaceCurrentItem(with: item)
+
+            guard wasPlaying else {
+                return
+            }
+
+            DispatchQueue.main.asyncAfter(deadline: .now() + 1) { [weak self] in
+                self?.play()
+            }
+        }
+    #else
+        func closePiP(wasPlaying: Bool) {
+            controller?.playerView.player = nil
+            controller?.playerView.player = avPlayer
+
+            guard wasPlaying else {
+                return
+            }
+
+            DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
+                self?.play()
+            }
+        }
+    #endif
+
+    func updateControls() {}
+    func startControlsUpdates() {}
+    func stopControlsUpdates() {}
+    func setNeedsDrawing(_: Bool) {}
+
+    private func loadSingleAsset(
+        _ url: URL,
+        stream: Stream,
+        of video: Video,
+        preservingTime: Bool = false
+    ) {
+        asset?.cancelLoading()
+        asset = AVURLAsset(url: url)
+        asset?.loadValuesAsynchronously(forKeys: Self.assetKeysToLoad) { [weak self] in
+            var error: NSError?
+            switch self?.asset?.statusOfValue(forKey: "duration", error: &error) {
+            case .loaded:
+                DispatchQueue.main.async { [weak self] in
+                    self?.insertPlayerItem(stream, for: video, preservingTime: preservingTime)
+                }
+            case .failed:
+                DispatchQueue.main.async { [weak self] in
+                    self?.model.playerError = error
+                }
+            default:
+                return
+            }
+        }
+    }
+
+    private func loadComposition(
+        _ stream: Stream,
+        of video: Video,
+        preservingTime: Bool = false
+    ) {
+        loadedCompositionAssets = []
+        loadCompositionAsset(stream.audioAsset, stream: stream, type: .audio, of: video, preservingTime: preservingTime, model: model)
+        loadCompositionAsset(stream.videoAsset, stream: stream, type: .video, of: video, preservingTime: preservingTime, model: model)
+    }
+
+    private func loadCompositionAsset(
+        _ asset: AVURLAsset,
+        stream: Stream,
+        type: AVMediaType,
+        of video: Video,
+        preservingTime: Bool = false,
+        model: PlayerModel
+    ) {
+        asset.loadValuesAsynchronously(forKeys: Self.assetKeysToLoad) { [weak self] in
+            guard let self = self else {
+                return
+            }
+            model.logger.info("loading \(type.rawValue) track")
+
+            let assetTracks = asset.tracks(withMediaType: type)
+
+            guard let compositionTrack = self.composition.addMutableTrack(
+                withMediaType: type,
+                preferredTrackID: kCMPersistentTrackID_Invalid
+            ) else {
+                model.logger.critical("composition \(type.rawValue) addMutableTrack FAILED")
+                return
+            }
+
+            guard let assetTrack = assetTracks.first else {
+                model.logger.critical("asset \(type.rawValue) track FAILED")
+                return
+            }
+
+            try! compositionTrack.insertTimeRange(
+                CMTimeRange(start: .zero, duration: CMTime.secondsInDefaultTimescale(video.length)),
+                of: assetTrack,
+                at: .zero
+            )
+
+            model.logger.critical("\(type.rawValue) LOADED")
+
+            guard model.streamSelection == stream else {
+                model.logger.critical("IGNORING LOADED")
+                return
+            }
+
+            self.loadedCompositionAssets.append(type)
+
+            if self.loadedCompositionAssets.count == 2 {
+                self.insertPlayerItem(stream, for: video, preservingTime: preservingTime)
+            }
+        }
+    }
+
+    private func insertPlayerItem(
+        _ stream: Stream,
+        for video: Video,
+        preservingTime: Bool = false
+    ) {
+        removeItemDidPlayToEndTimeObserver()
+
+        model.playerItem = playerItem(stream)
+        guard model.playerItem != nil else {
+            return
+        }
+
+        addItemDidPlayToEndTimeObserver()
+        attachMetadata(to: model.playerItem!, video: video, for: stream)
+
+        DispatchQueue.main.async {
+            self.stream = stream
+            self.video = video
+            self.model.stream = stream
+            self.composition = AVMutableComposition()
+            self.asset = nil
+        }
+
+        let startPlaying = {
+            #if !os(macOS)
+                try? AVAudioSession.sharedInstance().setActive(true)
+            #endif
+
+            if self.isAutoplaying(self.model.playerItem!) {
+                DispatchQueue.main.asyncAfter(deadline: .now() + 0.3) { [weak self] in
+                    guard let self = self else {
+                        return
+                    }
+
+                    if !preservingTime,
+                       let segment = self.model.sponsorBlock.segments.first,
+                       segment.start < 3,
+                       self.model.lastSkipped.isNil
+                    {
+                        self.avPlayer.seek(
+                            to: segment.endTime,
+                            toleranceBefore: .secondsInDefaultTimescale(1),
+                            toleranceAfter: .zero
+                        ) { finished in
+                            guard finished else {
+                                return
+                            }
+
+                            self.model.lastSkipped = segment
+                            self.model.play()
+                        }
+                    } else {
+                        self.model.play()
+                    }
+                }
+            }
+        }
+
+        let replaceItemAndSeek = {
+            guard video == self.model.currentVideo else {
+                return
+            }
+            self.avPlayer.replaceCurrentItem(with: self.model.playerItem)
+            self.seekToPreservedTime { finished in
+                guard finished else {
+                    return
+                }
+                self.model.preservedTime = nil
+
+                startPlaying()
+            }
+        }
+
+        if preservingTime {
+            if model.preservedTime.isNil {
+                model.saveTime {
+                    replaceItemAndSeek()
+                    startPlaying()
+                }
+            } else {
+                replaceItemAndSeek()
+                startPlaying()
+            }
+        } else {
+            avPlayer.replaceCurrentItem(with: model.playerItem)
+            startPlaying()
+        }
+    }
+
+    private func seekToPreservedTime(completionHandler: @escaping (Bool) -> Void = { _ in }) {
+        guard let time = model.preservedTime else {
+            return
+        }
+
+        avPlayer.seek(
+            to: time,
+            toleranceBefore: .secondsInDefaultTimescale(1),
+            toleranceAfter: .zero,
+            completionHandler: completionHandler
+        )
+    }
+
+    private func playerItem(_: Stream) -> AVPlayerItem? {
+        if let asset = asset {
+            return AVPlayerItem(asset: asset)
+        } else {
+            return AVPlayerItem(asset: composition)
+        }
+    }
+
+    private func attachMetadata(to item: AVPlayerItem, video: Video, for _: Stream? = nil) {
+        #if !os(macOS)
+            var externalMetadata = [
+                makeMetadataItem(.commonIdentifierTitle, value: video.title),
+                makeMetadataItem(.quickTimeMetadataGenre, value: video.genre ?? ""),
+                makeMetadataItem(.commonIdentifierDescription, value: video.description ?? "")
+            ]
+            if let thumbnailData = try? Data(contentsOf: video.thumbnailURL(quality: .medium)!),
+               let image = UIImage(data: thumbnailData),
+               let pngData = image.pngData()
+            {
+                let artworkItem = makeMetadataItem(.commonIdentifierArtwork, value: pngData)
+                externalMetadata.append(artworkItem)
+            }
+
+            item.externalMetadata = externalMetadata
+        #endif
+
+        item.preferredForwardBufferDuration = 5
+
+        observePlayerItemStatus(item)
+    }
+
+    #if !os(macOS)
+        private func makeMetadataItem(_ identifier: AVMetadataIdentifier, value: Any) -> AVMetadataItem {
+            let item = AVMutableMetadataItem()
+
+            item.identifier = identifier
+            item.value = value as? NSCopying & NSObjectProtocol
+            item.extendedLanguageTag = "und"
+
+            return item.copy() as! AVMetadataItem
+        }
+    #endif
+
+    func isAutoplaying(_ item: AVPlayerItem) -> Bool {
+        avPlayer.currentItem == item
+    }
+
+    private func observePlayerItemStatus(_ item: AVPlayerItem) {
+        statusObservation?.invalidate()
+        statusObservation = item.observe(\.status, options: [.old, .new]) { [weak self] playerItem, _ in
+            guard let self = self else {
+                return
+            }
+
+            switch playerItem.status {
+            case .readyToPlay:
+                if self.isAutoplaying(playerItem) {
+                    self.model.play()
+                }
+            case .failed:
+                self.model.playerError = item.error
+
+            default:
+                return
+            }
+        }
+    }
+
+    private func addItemDidPlayToEndTimeObserver() {
+        NotificationCenter.default.addObserver(
+            self,
+            selector: #selector(itemDidPlayToEndTime),
+            name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
+            object: playerItem
+        )
+    }
+
+    private func removeItemDidPlayToEndTimeObserver() {
+        NotificationCenter.default.removeObserver(
+            self,
+            name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
+            object: playerItem
+        )
+    }
+
+    @objc func itemDidPlayToEndTime() {
+        model.prepareCurrentItemForHistory(finished: true)
+
+        if model.queue.isEmpty {
+            #if !os(macOS)
+                try? AVAudioSession.sharedInstance().setActive(false)
+            #endif
+            model.resetQueue()
+            #if os(tvOS)
+                controller?.playerView.dismiss(animated: false) { [weak self] in
+                    self?.controller?.dismiss(animated: true)
+                }
+            #else
+                model.hide()
+            #endif
+        } else {
+            model.advanceToNextItem()
+        }
+    }
+
+    private func addFrequentTimeObserver() {
+        let interval = CMTime.secondsInDefaultTimescale(0.5)
+
+        frequentTimeObserver = avPlayer.addPeriodicTimeObserver(
+            forInterval: interval,
+            queue: .main
+        ) { [weak self] _ in
+            guard let self = self else {
+                return
+            }
+
+            guard !self.model.currentItem.isNil else {
+                return
+            }
+
+            self.controls.duration = self.playerItemDuration ?? .zero
+            self.controls.currentTime = self.currentTime ?? .zero
+
+            #if !os(tvOS)
+                self.updateNowPlayingInfo()
+            #endif
+
+            if let currentTime = self.currentTime {
+                self.model.handleSegments(at: currentTime)
+            }
+        }
+    }
+
+    private func addInfrequentTimeObserver() {
+        let interval = CMTime.secondsInDefaultTimescale(5)
+
+        infrequentTimeObserver = avPlayer.addPeriodicTimeObserver(
+            forInterval: interval,
+            queue: .main
+        ) { [weak self] _ in
+            guard let self = self else {
+                return
+            }
+
+            guard !self.model.currentItem.isNil else {
+                return
+            }
+
+            self.timeObserverThrottle.execute {
+                self.model.updateWatch()
+            }
+        }
+    }
+
+    private func addPlayerTimeControlStatusObserver() {
+        playerTimeControlStatusObserver = avPlayer.observe(\.timeControlStatus) { [weak self] player, _ in
+            guard let self = self,
+                  self.avPlayer == player
+            else {
+                return
+            }
+
+            DispatchQueue.main.async {
+                self.controls.isPlaying = player.timeControlStatus == .playing
+            }
+
+            if player.timeControlStatus != .waitingToPlayAtSpecifiedRate {
+                DispatchQueue.main.async { [weak self] in
+                    self?.model.objectWillChange.send()
+                }
+            }
+
+            if player.timeControlStatus == .playing, player.rate != self.model.currentRate {
+                player.rate = self.model.currentRate
+            }
+
+            #if os(macOS)
+                if player.timeControlStatus == .playing {
+                    ScreenSaverManager.shared.disable(reason: "Yattee is playing video")
+                } else {
+                    ScreenSaverManager.shared.enable()
+                }
+            #endif
+
+            self.timeObserverThrottle.execute {
+                self.model.updateWatch()
+            }
+        }
+    }
+
+    private func updateCurrentArtwork() {
+        guard let thumbnailData = try? Data(contentsOf: model.currentItem.video.thumbnailURL(quality: .medium)!) else {
+            return
+        }
+
+        #if os(macOS)
+            let image = NSImage(data: thumbnailData)
+        #else
+            let image = UIImage(data: thumbnailData)
+        #endif
+
+        if image.isNil {
+            return
+        }
+
+        currentArtwork = MPMediaItemArtwork(boundsSize: image!.size) { _ in image! }
+    }
+
+    fileprivate func updateNowPlayingInfo() {
+        var nowPlayingInfo: [String: AnyObject] = [
+            MPMediaItemPropertyTitle: model.currentItem.video.title as AnyObject,
+            MPMediaItemPropertyArtist: model.currentItem.video.author as AnyObject,
+            MPNowPlayingInfoPropertyIsLiveStream: model.currentItem.video.live as AnyObject,
+            MPNowPlayingInfoPropertyElapsedPlaybackTime: avPlayer.currentTime().seconds as AnyObject,
+            MPNowPlayingInfoPropertyPlaybackQueueCount: model.queue.count as AnyObject,
+            MPMediaItemPropertyMediaType: MPMediaType.anyVideo.rawValue as AnyObject
+        ]
+
+        if !currentArtwork.isNil {
+            nowPlayingInfo[MPMediaItemPropertyArtwork] = currentArtwork as AnyObject
+        }
+
+        if !model.currentItem.video.live {
+            let itemDuration = model.currentItem.videoDuration ?? model.currentItem.duration
+            let duration = itemDuration.isFinite ? Double(itemDuration) : nil
+
+            if !duration.isNil {
+                nowPlayingInfo[MPMediaItemPropertyPlaybackDuration] = duration as AnyObject
+            }
+        }
+
+        MPNowPlayingInfoCenter.default().nowPlayingInfo = nowPlayingInfo
+    }
+}

Model/Player/Backends/MPVBackend.swift

@@ -0,0 +1,305 @@
+import AVFAudio
+import CoreMedia
+import Foundation
+import Logging
+import SwiftUI
+
+final class MPVBackend: PlayerBackend {
+    private var logger = Logger(label: "mpv-backend")
+
+    var model: PlayerModel!
+    var controls: PlayerControlsModel!
+
+    var stream: Stream?
+    var video: Video?
+    var currentTime: CMTime?
+
+    var loadedVideo = false
+    var isLoadingVideo = true
+
+    var isPlaying = true { didSet {
+        if isPlaying {
+            startClientUpdates()
+        } else {
+            stopControlsUpdates()
+        }
+
+        updateControlsIsPlaying()
+    }}
+    var playerItemDuration: CMTime?
+
+    var controller: MPVViewController!
+    var client: MPVClient! { didSet { client.backend = self } }
+
+    private var clientTimer: RepeatingTimer!
+
+    private var onFileLoaded: (() -> Void)?
+
+    private var controlsUpdates = false
+    private var timeObserverThrottle = Throttle(interval: 2)
+
+    init(model: PlayerModel, controls: PlayerControlsModel? = nil) {
+        self.model = model
+        self.controls = controls
+
+        clientTimer = .init(timeInterval: 1)
+        clientTimer.eventHandler = getClientUpdates
+    }
+
+    func bestPlayable(_ streams: [Stream]) -> Stream? {
+        streams.filter { $0.kind == .adaptive }.max { $0.resolution < $1.resolution } ??
+            streams.first { $0.kind == .hls } ??
+            streams.first
+    }
+
+    func canPlay(_ stream: Stream) -> Bool {
+        stream.resolution != .unknown && stream.format != "AV1"
+    }
+
+    func playStream(_ stream: Stream, of video: Video, preservingTime: Bool, upgrading _: Bool) {
+        let updateCurrentStream = {
+            DispatchQueue.main.async { [weak self] in
+                self?.stream = stream
+                self?.video = video
+                self?.model.stream = stream
+            }
+        }
+
+        let startPlaying = {
+            #if !os(macOS)
+                try? AVAudioSession.sharedInstance().setActive(true)
+            #endif
+
+            DispatchQueue.main.async { [weak self] in
+                guard let self = self else {
+                    return
+                }
+
+                self.startClientUpdates()
+
+                if !preservingTime,
+                   let segment = self.model.sponsorBlock.segments.first,
+                   segment.start < 3,
+                   self.model.lastSkipped.isNil
+                {
+                    self.seek(to: segment.endTime) { finished in
+                        guard finished else {
+                            return
+                        }
+
+                        self.model.lastSkipped = segment
+                        self.play()
+                    }
+                } else {
+                    self.play()
+                }
+            }
+        }
+
+        let replaceItem: (CMTime?) -> Void = { [weak self] time in
+            guard let self = self else {
+                return
+            }
+
+            self.stop()
+
+            if let url = stream.singleAssetURL {
+                self.onFileLoaded = { [weak self] in
+                    self?.setIsLoadingVideo(false)
+                    updateCurrentStream()
+                    startPlaying()
+                }
+
+                self.client.loadFile(url, time: time) { [weak self] _ in
+                    self?.setIsLoadingVideo(true)
+                }
+            } else {
+                self.onFileLoaded = { [weak self] in
+                    self?.client.addAudio(stream.audioAsset.url) { _ in
+                        self?.setIsLoadingVideo(false)
+                        updateCurrentStream()
+                        startPlaying()
+                    }
+                }
+
+                self.client.loadFile(stream.videoAsset.url, time: time) { [weak self] _ in
+                    self?.setIsLoadingVideo(true)
+                    self?.pause()
+                }
+            }
+        }
+
+        if preservingTime {
+            if model.preservedTime.isNil {
+                model.saveTime {
+                    replaceItem(self.model.preservedTime)
+                }
+            } else {
+                replaceItem(self.model.preservedTime)
+            }
+        } else {
+            replaceItem(nil)
+        }
+    }
+
+    func play() {
+        isPlaying = true
+        startClientUpdates()
+
+        client?.play()
+    }
+
+    func pause() {
+        isPlaying = false
+        stopClientUpdates()
+
+        client?.pause()
+    }
+
+    func togglePlay() {
+        isPlaying ? pause() : play()
+    }
+
+    func stop() {
+        client?.stop()
+    }
+
+    func seek(to time: CMTime, completionHandler: ((Bool) -> Void)?) {
+        client.seek(to: time) { [weak self] _ in
+            self?.getClientUpdates()
+            self?.updateControls()
+            completionHandler?(true)
+        }
+    }
+
+    func seek(relative time: CMTime, completionHandler: ((Bool) -> Void)? = nil) {
+        client.seek(relative: time) { [weak self] _ in
+            self?.getClientUpdates()
+            self?.updateControls()
+            completionHandler?(true)
+        }
+    }
+
+    func setRate(_: Float) {
+        // TODO: Implement rate change
+    }
+
+    func closeItem() {}
+
+    func enterFullScreen() {}
+
+    func exitFullScreen() {}
+
+    func closePiP(wasPlaying _: Bool) {}
+
+    func updateControls() {
+        DispatchQueue.main.async { [weak self] in
+            self?.logger.info("updating controls")
+            self?.controls.currentTime = self?.currentTime ?? .zero
+            self?.controls.duration = self?.playerItemDuration ?? .zero
+        }
+    }
+
+    func startControlsUpdates() {
+        self.logger.info("starting controls updates")
+        controlsUpdates = true
+    }
+
+    func stopControlsUpdates() {
+        self.logger.info("stopping controls updates")
+        controlsUpdates = false
+    }
+
+    func startClientUpdates() {
+        clientTimer.resume()
+    }
+
+    private func getClientUpdates() {
+        self.logger.info("getting client updates")
+
+        currentTime = client?.currentTime
+        playerItemDuration = client?.duration
+
+        if controlsUpdates {
+            updateControls()
+        }
+
+        if let currentTime = currentTime {
+            model.handleSegments(at: currentTime)
+        }
+
+        self.timeObserverThrottle.execute {
+            self.model.updateWatch()
+        }
+    }
+
+    private func stopClientUpdates() {
+        clientTimer.suspend()
+    }
+
+    private func updateControlsIsPlaying() {
+        DispatchQueue.main.async { [weak self] in
+            self?.controls.isPlaying = self?.isPlaying ?? false
+        }
+    }
+
+    private func setIsLoadingVideo(_ value: Bool) {
+        isLoadingVideo = value
+        DispatchQueue.main.async { [weak self] in
+            self?.controls.isLoadingVideo = value
+        }
+    }
+
+    func handle(_ event: UnsafePointer<mpv_event>!) {
+        logger.info("\(String(cString: mpv_event_name(event.pointee.event_id)))")
+
+        switch event.pointee.event_id {
+        case MPV_EVENT_SHUTDOWN:
+            mpv_destroy(client.mpv)
+            client.mpv = nil
+
+        case MPV_EVENT_LOG_MESSAGE:
+            let logmsg = UnsafeMutablePointer<mpv_event_log_message>(OpaquePointer(event.pointee.data))
+            logger.info(.init(stringLiteral: "log: \(String(cString: (logmsg!.pointee.prefix)!)), "
+                    + "\(String(cString: (logmsg!.pointee.level)!)), "
+                    + "\(String(cString: (logmsg!.pointee.text)!))"))
+
+        case MPV_EVENT_FILE_LOADED:
+            onFileLoaded?()
+            onFileLoaded = nil
+
+        case MPV_EVENT_END_FILE:
+            break
+            // DispatchQueue.main.async { [weak self] in
+            // TODO: handle EOF
+            // self?.handleEndOfFile(event)
+            // }
+
+        default:
+            logger.info(.init(stringLiteral: "event: \(String(cString: mpv_event_name(event.pointee.event_id)))"))
+        }
+    }
+
+    func handleEndOfFile(_: UnsafePointer<mpv_event>!) {
+        guard !isLoadingVideo else {
+            return
+        }
+
+        model.prepareCurrentItemForHistory(finished: true)
+
+        if model.queue.isEmpty {
+            #if !os(macOS)
+                try? AVAudioSession.sharedInstance().setActive(false)
+            #endif
+            model.resetQueue()
+
+            model.hide()
+        } else {
+            model.advanceToNextItem()
+        }
+    }
+
+    func setNeedsDrawing(_ needsDrawing: Bool) {
+        client?.setNeedsDrawing(needsDrawing)
+    }
+}

Model/Player/Backends/MPVClient.swift

@@ -0,0 +1,229 @@
+import Foundation
+import Logging
+#if !os(macOS)
+    import CoreMedia
+    import Siesta
+    import UIKit
+#endif
+
+final class MPVClient: ObservableObject {
+    private var logger = Logger(label: "mpv-client")
+
+    var mpv: OpaquePointer!
+    var mpvGL: OpaquePointer!
+    var queue: DispatchQueue!
+    var glView: MPVOGLView!
+    var backend: MPVBackend!
+
+    func create(frame: CGRect) -> MPVOGLView {
+        glView = MPVOGLView(frame: frame)
+
+        mpv = mpv_create()
+        if mpv == nil {
+            print("failed creating context\n")
+            exit(1)
+        }
+
+        checkError(mpv_request_log_messages(mpv, "warn"))
+        checkError(mpv_initialize(mpv))
+        checkError(mpv_set_option_string(mpv, "vo", "libmpv"))
+        checkError(mpv_set_option_string(mpv, "hwdec", "yes"))
+
+        checkError(mpv_set_option_string(mpv, "override-display-fps", "\(UIScreen.main.maximumFramesPerSecond)"))
+        checkError(mpv_set_option_string(mpv, "video-sync", "display-resample"))
+
+        let api = UnsafeMutableRawPointer(mutating: (MPV_RENDER_API_TYPE_OPENGL as NSString).utf8String)
+        var initParams = mpv_opengl_init_params(
+            get_proc_address: getProcAddress(_:_:),
+            get_proc_address_ctx: nil,
+            extra_exts: nil
+        )
+
+        withUnsafeMutablePointer(to: &initParams) { initParams in
+            var params = [
+                mpv_render_param(type: MPV_RENDER_PARAM_API_TYPE, data: api),
+                mpv_render_param(type: MPV_RENDER_PARAM_OPENGL_INIT_PARAMS, data: initParams),
+                mpv_render_param()
+            ]
+
+            var mpvGL: OpaquePointer?
+
+            if mpv_render_context_create(&mpvGL, mpv, &params) < 0 {
+                puts("failed to initialize mpv GL context")
+                exit(1)
+            }
+
+            glView.mpvGL = UnsafeMutableRawPointer(mpvGL)
+
+            mpv_render_context_set_update_callback(
+                mpvGL,
+                glUpdate(_:),
+                UnsafeMutableRawPointer(Unmanaged.passUnretained(glView).toOpaque())
+            )
+        }
+
+        queue = DispatchQueue(label: "mpv", qos: .background)
+        queue!.async {
+            mpv_set_wakeup_callback(self.mpv, wakeUp, UnsafeMutableRawPointer(Unmanaged.passUnretained(self).toOpaque()))
+        }
+
+        return glView
+    }
+
+    func readEvents() {
+        queue?.async { [self] in
+            while self.mpv != nil {
+                let event = mpv_wait_event(self.mpv, 0)
+                if event!.pointee.event_id == MPV_EVENT_NONE {
+                    break
+                }
+                backend.handle(event)
+            }
+        }
+    }
+
+    func loadFile(_ url: URL, time: CMTime? = nil, completionHandler: ((Int32) -> Void)? = nil) {
+        var args = [url.absoluteString]
+        if let time = time {
+            args.append("replace")
+            args.append("start=\(Int(time.seconds))")
+        }
+
+        command("loadfile", args: args, returnValueCallback: completionHandler)
+    }
+
+    func addAudio(_ url: URL, completionHandler: ((Int32) -> Void)? = nil) {
+        command("audio-add", args: [url.absoluteString], returnValueCallback: completionHandler)
+    }
+
+    func play() {
+        setFlagAsync("pause", false)
+    }
+
+    func pause() {
+        setFlagAsync("pause", true)
+    }
+
+    func togglePlay() {
+        command("cycle", args: ["pause"])
+    }
+
+    func stop() {
+        command("stop")
+    }
+
+    var currentTime: CMTime {
+        CMTime.secondsInDefaultTimescale(getDouble("time-pos"))
+    }
+
+    var duration: CMTime {
+        CMTime.secondsInDefaultTimescale(getDouble("duration"))
+    }
+
+    func seek(relative time: CMTime, completionHandler: ((Bool) -> Void)? = nil) {
+        command("seek", args: [String(time.seconds)]) { _ in
+            completionHandler?(true)
+        }
+    }
+
+    func seek(to time: CMTime, completionHandler: ((Bool) -> Void)? = nil) {
+        command("seek", args: [String(time.seconds), "absolute"]) { _ in
+            completionHandler?(true)
+        }
+    }
+
+    func setSize(_ width: Double, _ height: Double) {
+        logger.info("setting player size to \(width),\(height)")
+        #if !os(macOS)
+            guard width <= UIScreen.main.bounds.width, height <= UIScreen.main.bounds.height else {
+                logger.info("requested size is greater than screen size, ignoring")
+                return
+            }
+        #endif
+
+        glView?.frame = CGRect(x: 0, y: 0, width: width, height: height)
+    }
+
+    func setNeedsDrawing(_ needsDrawing: Bool) {
+        logger.info("needs drawing: \(needsDrawing)")
+        glView.needsDrawing = needsDrawing
+    }
+
+    func command(
+        _ command: String,
+        args: [String?] = [],
+        checkForErrors: Bool = true,
+        returnValueCallback: ((Int32) -> Void)? = nil
+    ) {
+        guard mpv != nil else {
+            return
+        }
+        var cargs = makeCArgs(command, args).map { $0.flatMap { UnsafePointer<CChar>(strdup($0)) } }
+        defer {
+            for ptr in cargs where ptr != nil {
+                free(UnsafeMutablePointer(mutating: ptr!))
+            }
+        }
+        logger.info("\(command) -- \(args)")
+        let returnValue = mpv_command(mpv, &cargs)
+        if checkForErrors {
+            checkError(returnValue)
+        }
+        if let cb = returnValueCallback {
+            cb(returnValue)
+        }
+    }
+
+    private func setFlagAsync(_ name: String, _ flag: Bool) {
+        var data: Int = flag ? 1 : 0
+        mpv_set_property_async(mpv, 0, name, MPV_FORMAT_FLAG, &data)
+    }
+
+    private func getDouble(_ name: String) -> Double {
+        var data = Double()
+        mpv_get_property(mpv, name, MPV_FORMAT_DOUBLE, &data)
+        return data
+    }
+
+    private func makeCArgs(_ command: String, _ args: [String?]) -> [String?] {
+        if !args.isEmpty, args.last == nil {
+            fatalError("Command do not need a nil suffix")
+        }
+
+        var strArgs = args
+        strArgs.insert(command, at: 0)
+        strArgs.append(nil)
+
+        return strArgs
+    }
+
+    func checkError(_ status: CInt) {
+        if status < 0 {
+            logger.error(.init(stringLiteral: "MPV API error: \(String(cString: mpv_error_string(status)))\n"))
+        }
+    }
+}
+
+private func getProcAddress(_: UnsafeMutableRawPointer?, _ name: UnsafePointer<Int8>?) -> UnsafeMutableRawPointer? {
+    let symbolName = CFStringCreateWithCString(kCFAllocatorDefault, name, CFStringBuiltInEncodings.ASCII.rawValue)
+    let addr = CFBundleGetFunctionPointerForName(CFBundleGetBundleWithIdentifier("com.apple.opengles" as CFString), symbolName)
+
+    return addr
+}
+
+private func glUpdate(_ ctx: UnsafeMutableRawPointer?) {
+    let glView = unsafeBitCast(ctx, to: MPVOGLView.self)
+
+    guard glView.needsDrawing else {
+        return
+    }
+
+    DispatchQueue.main.async {
+        glView.setNeedsDisplay()
+    }
+}
+
+private func wakeUp(_ context: UnsafeMutableRawPointer?) {
+    let client = unsafeBitCast(context, to: MPVClient.self)
+    client.readEvents()
+}

Model/Player/Backends/PlayerBackend.swift

@@ -0,0 +1,67 @@
+import CoreMedia
+import Defaults
+import Foundation
+
+protocol PlayerBackend {
+    var model: PlayerModel! { get set }
+    var controls: PlayerControlsModel! { get set }
+
+    var stream: Stream? { get set }
+    var video: Video? { get set }
+    var currentTime: CMTime? { get }
+
+    var loadedVideo: Bool { get }
+    var isLoadingVideo: Bool { get }
+
+    var isPlaying: Bool { get }
+    var playerItemDuration: CMTime? { get }
+
+    func bestPlayable(_ streams: [Stream]) -> Stream?
+    func canPlay(_ stream: Stream) -> Bool
+
+    func playStream(
+        _ stream: Stream,
+        of video: Video,
+        preservingTime: Bool,
+        upgrading: Bool
+    )
+
+    func play()
+    func pause()
+    func togglePlay()
+
+    func stop()
+
+    func seek(to time: CMTime, completionHandler: ((Bool) -> Void)?)
+    func seek(to seconds: Double, completionHandler: ((Bool) -> Void)?)
+    func seek(relative time: CMTime, completionHandler: ((Bool) -> Void)?)
+
+    func setRate(_ rate: Float)
+
+    func closeItem()
+
+    func enterFullScreen()
+    func exitFullScreen()
+
+    func closePiP(wasPlaying: Bool)
+
+    func updateControls()
+    func startControlsUpdates()
+    func stopControlsUpdates()
+
+    func setNeedsDrawing(_ needsDrawing: Bool)
+}
+
+extension PlayerBackend {
+    func seek(to time: CMTime, completionHandler: ((Bool) -> Void)? = nil) {
+        seek(to: time, completionHandler: completionHandler)
+    }
+
+    func seek(to seconds: Double, completionHandler: ((Bool) -> Void)? = nil) {
+        seek(to: .secondsInDefaultTimescale(seconds), completionHandler: completionHandler)
+    }
+
+    func seek(relative time: CMTime, completionHandler: ((Bool) -> Void)? = nil) {
+        seek(relative: time, completionHandler: completionHandler)
+    }
+}

Model/Player/Backends/PlayerBackendType.swift

@@ -0,0 +1,16 @@
+import Defaults
+import Foundation
+
+enum PlayerBackendType: String, CaseIterable, Defaults.Serializable {
+    case mpv
+    case appleAVPlayer
+
+    var label: String {
+        switch self {
+        case .mpv:
+            return "MPV"
+        case .appleAVPlayer:
+            return "AVPlayer"
+        }
+    }
+}