//
// Swiftfin is subject to the terms of the Mozilla Public
// License, v2.0. If a copy of the MPL was not distributed with this
// file, you can obtain one at https://mozilla.org/MPL/2.0/.
//
// Copyright (c) 2022 Jellyfin & Jellyfin Contributors
//

import Combine
import Defaults
import JellyfinAPI
import UIKit

extension BaseItemDto {
    func createVideoPlayerViewModel() -> AnyPublisher<[VideoPlayerViewModel], Error> {

        LogManager.log.debug("Creating video player view model for item: \(id ?? "")")

        let builder = DeviceProfileBuilder()
        // TODO: fix bitrate settings
        let tempOverkillBitrate = 360_000_000
        builder.setMaxBitrate(bitrate: tempOverkillBitrate)
        let profile = builder.buildProfile()

        let getPostedPlaybackInfoRequest = GetPostedPlaybackInfoRequest(
            userId: SessionManager.main.currentLogin.user.id,
            maxStreamingBitrate: tempOverkillBitrate,
            startTimeTicks: self.userData?.playbackPositionTicks ?? 0,
            deviceProfile: profile,
            autoOpenLiveStream: true
        )

        return MediaInfoAPI.getPostedPlaybackInfo(
            itemId: self.id!,
            userId: SessionManager.main.currentLogin.user.id,
            maxStreamingBitrate: tempOverkillBitrate,
            startTimeTicks: self.userData?.playbackPositionTicks ?? 0,
            autoOpenLiveStream: true,
            getPostedPlaybackInfoRequest: getPostedPlaybackInfoRequest
        )
        .map { response -> [VideoPlayerViewModel] in
            let mediaSources = response.mediaSources!

            var viewModels: [VideoPlayerViewModel] = []

            for currentMediaSource in mediaSources {
                let videoStream = currentMediaSource.mediaStreams?.filter { $0.type == .video }.first
                let audioStreams = currentMediaSource.mediaStreams?.filter { $0.type == .audio } ?? []
                let subtitleStreams = currentMediaSource.mediaStreams?.filter { $0.type == .subtitle } ?? []

                let defaultAudioStream = audioStreams.first(where: { $0.index! == currentMediaSource.defaultAudioStreamIndex! })

                let defaultSubtitleStream = subtitleStreams
                    .first(where: { $0.index! == currentMediaSource.defaultSubtitleStreamIndex ?? -1 })

                // MARK: Build Streams

                let directStreamURL: URL
                let transcodedStreamURL: URLComponents?
                var hlsStreamURL: URL
                let mediaSourceID: String
                let streamType: ServerStreamType

                if mediaSources.count > 1 {
                    mediaSourceID = currentMediaSource.id!
                } else {
                    mediaSourceID = self.id!
                }

                let directStreamBuilder = VideosAPI.getVideoStreamWithRequestBuilder(
                    itemId: self.id!,
                    _static: true,
                    tag: self.etag,
                    playSessionId: response.playSessionId,
                    minSegments: 6,
                    mediaSourceId: mediaSourceID
                )
                directStreamURL = URL(string: directStreamBuilder.URLString)!

                if let transcodeURL = currentMediaSource.transcodingUrl {
                    streamType = .transcode
                    transcodedStreamURL = URLComponents(
                        string: SessionManager.main.currentLogin.server.currentURI
                            .appending(transcodeURL)
                    )!
                } else {
                    streamType = .direct
                    transcodedStreamURL = nil
                }

                let hlsStreamBuilder = DynamicHlsAPI.getMasterHlsVideoPlaylistWithRequestBuilder(
                    itemId: id ?? "",
                    mediaSourceId: id ?? "",
                    _static: true,
                    tag: currentMediaSource.eTag,
                    deviceProfileId: nil,
                    playSessionId: response.playSessionId,
                    segmentContainer: "ts",
                    segmentLength: nil,
                    minSegments: 2,
                    deviceId: UIDevice.vendorUUIDString,
                    audioCodec: audioStreams
                        .compactMap(\.codec)
                        .joined(separator: ","),
                    breakOnNonKeyFrames: true,
                    requireAvc: true,
                    transcodingMaxAudioChannels: 6,
                    videoCodec: videoStream?.codec,
                    videoStreamIndex: videoStream?.index,
                    enableAdaptiveBitrateStreaming: true
                )

                var hlsStreamComponents = URLComponents(string: hlsStreamBuilder.URLString)!
                hlsStreamComponents.addQueryItem(name: "api_key", value: SessionManager.main.currentLogin.user.accessToken)

                hlsStreamURL = hlsStreamComponents.url!

                // MARK: VidoPlayerViewModel Creation

                var subtitle: String?

                // MARK: Attach media content to self

                var modifiedSelfItem = self
                modifiedSelfItem.mediaStreams = currentMediaSource.mediaStreams

                // TODO: other forms of media subtitle
                if self.type == .episode {
                    if let seriesName = self.seriesName, let episodeLocator = self.episodeLocator {
                        subtitle = "\(seriesName) - \(episodeLocator)"
                    }
                }

                let subtitlesEnabled = defaultSubtitleStream != nil

                let shouldShowAutoPlay = Defaults[.shouldShowAutoPlay] && type == .episode
                let autoplayEnabled = Defaults[.autoplayEnabled] && shouldShowAutoPlay

                let overlayType = Defaults[.overlayType]

                let shouldShowPlayPreviousItem = Defaults[.shouldShowPlayPreviousItem] && type == .episode
                let shouldShowPlayNextItem = Defaults[.shouldShowPlayNextItem] && type == .episode

                var fileName: String?
                if let lastInPath = currentMediaSource.path?.split(separator: "/").last {
                    fileName = String(lastInPath)
                }

                let videoPlayerViewModel = VideoPlayerViewModel(
                    item: modifiedSelfItem,
                    title: modifiedSelfItem.name ?? "",
                    subtitle: subtitle,
                    directStreamURL: directStreamURL,
                    transcodedStreamURL: transcodedStreamURL?.url,
                    hlsStreamURL: hlsStreamURL,
                    streamType: streamType,
                    response: response,
                    videoStream: videoStream!,
                    audioStreams: audioStreams,
                    subtitleStreams: subtitleStreams,
                    chapters: modifiedSelfItem.chapters ?? [],
                    selectedAudioStreamIndex: defaultAudioStream?.index ?? -1,
                    selectedSubtitleStreamIndex: defaultSubtitleStream?.index ?? -1,
                    subtitlesEnabled: subtitlesEnabled,
                    autoplayEnabled: autoplayEnabled,
                    overlayType: overlayType,
                    shouldShowPlayPreviousItem: shouldShowPlayPreviousItem,
                    shouldShowPlayNextItem: shouldShowPlayNextItem,
                    shouldShowAutoPlay: shouldShowAutoPlay,
                    container: currentMediaSource.container ?? "",
                    filename: fileName,
                    versionName: currentMediaSource.name
                )

                viewModels.append(videoPlayerViewModel)
            }

            return viewModels
        }
        .eraseToAnyPublisher()
    }

    func createLiveTVVideoPlayerViewModel() -> AnyPublisher<[VideoPlayerViewModel], Error> {

        LogManager.log.debug("Creating liveTV video player view model for item: \(id ?? "")")

        let builder = DeviceProfileBuilder()
        // TODO: fix bitrate settings
        let tempOverkillBitrate = 360_000_000
        builder.setMaxBitrate(bitrate: tempOverkillBitrate)
        let profile = builder.buildProfile()

        let getPostedPlaybackInfoRequest = GetPostedPlaybackInfoRequest(
            userId: SessionManager.main.currentLogin.user.id,
            maxStreamingBitrate: tempOverkillBitrate,
            startTimeTicks: self.userData?.playbackPositionTicks ?? 0,
            deviceProfile: profile,
            autoOpenLiveStream: true
        )

        return MediaInfoAPI.getPostedPlaybackInfo(
            itemId: self.id!,
            userId: SessionManager.main.currentLogin.user.id,
            maxStreamingBitrate: tempOverkillBitrate,
            startTimeTicks: self.userData?.playbackPositionTicks ?? 0,
            autoOpenLiveStream: true,
            getPostedPlaybackInfoRequest: getPostedPlaybackInfoRequest
        )
        .map { response -> [VideoPlayerViewModel] in
            let mediaSources = response.mediaSources!

            var viewModels: [VideoPlayerViewModel] = []

            for currentMediaSource in mediaSources {
                let videoStream = currentMediaSource.mediaStreams?.filter { $0.type == .video }.first
                let audioStreams = currentMediaSource.mediaStreams?.filter { $0.type == .audio } ?? []
                let subtitleStreams = currentMediaSource.mediaStreams?.filter { $0.type == .subtitle } ?? []

                let defaultAudioStream = audioStreams.first(where: { $0.index! == currentMediaSource.defaultAudioStreamIndex! })

                let defaultSubtitleStream = subtitleStreams
                    .first(where: { $0.index! == currentMediaSource.defaultSubtitleStreamIndex ?? -1 })

                // MARK: Build Streams

                let directStreamURL: URL
                let transcodedStreamURL: URLComponents?
                var hlsStreamURL: URL
                let mediaSourceID: String
                let streamType: ServerStreamType

                if mediaSources.count > 1 {
                    mediaSourceID = currentMediaSource.id!
                } else {
                    mediaSourceID = self.id!
                }

                let directStreamBuilder = VideosAPI.getVideoStreamWithRequestBuilder(
                    itemId: self.id!,
                    _static: true,
                    tag: self.etag,
                    playSessionId: response.playSessionId,
                    minSegments: 6,
                    mediaSourceId: mediaSourceID
                )
                directStreamURL = URL(string: directStreamBuilder.URLString)!

                if let transcodeURL = currentMediaSource.transcodingUrl, !Defaults[.Experimental.liveTVForceDirectPlay] {
                    streamType = .transcode
                    transcodedStreamURL = URLComponents(
                        string: SessionManager.main.currentLogin.server.currentURI
                            .appending(transcodeURL)
                    )!
                } else {
                    streamType = .direct
                    transcodedStreamURL = nil
                }

                let hlsStreamBuilder = DynamicHlsAPI.getMasterHlsVideoPlaylistWithRequestBuilder(
                    itemId: id ?? "",
                    mediaSourceId: id ?? "",
                    _static: true,
                    tag: currentMediaSource.eTag,
                    deviceProfileId: nil,
                    playSessionId: response.playSessionId,
                    segmentContainer: "ts",
                    segmentLength: nil,
                    minSegments: 2,
                    deviceId: UIDevice.vendorUUIDString,
                    audioCodec: audioStreams
                        .compactMap(\.codec)
                        .joined(separator: ","),
                    breakOnNonKeyFrames: true,
                    requireAvc: true,
                    transcodingMaxAudioChannels: 6,
                    videoCodec: videoStream?.codec,
                    videoStreamIndex: videoStream?.index,
                    enableAdaptiveBitrateStreaming: true
                )

                var hlsStreamComponents = URLComponents(string: hlsStreamBuilder.URLString)!
                hlsStreamComponents.addQueryItem(name: "api_key", value: SessionManager.main.currentLogin.user.accessToken)

                hlsStreamURL = hlsStreamComponents.url!

                // MARK: VidoPlayerViewModel Creation

                var subtitle: String?

                // MARK: Attach media content to self

                var modifiedSelfItem = self
                modifiedSelfItem.mediaStreams = currentMediaSource.mediaStreams

                // TODO: other forms of media subtitle
                if self.type == .episode {
                    if let seriesName = self.seriesName, let episodeLocator = self.episodeLocator {
                        subtitle = "\(seriesName) - \(episodeLocator)"
                    }
                }

                let subtitlesEnabled = defaultSubtitleStream != nil

                let shouldShowAutoPlay = Defaults[.shouldShowAutoPlay] && type == .episode
                let autoplayEnabled = Defaults[.autoplayEnabled] && shouldShowAutoPlay

                let overlayType = Defaults[.overlayType]

                let shouldShowPlayPreviousItem = Defaults[.shouldShowPlayPreviousItem] && type == .episode
                let shouldShowPlayNextItem = Defaults[.shouldShowPlayNextItem] && type == .episode

                var fileName: String?
                if let lastInPath = currentMediaSource.path?.split(separator: "/").last {
                    fileName = String(lastInPath)
                }

                let videoPlayerViewModel = VideoPlayerViewModel(
                    item: modifiedSelfItem,
                    title: modifiedSelfItem.name ?? "",
                    subtitle: subtitle,
                    directStreamURL: directStreamURL,
                    transcodedStreamURL: transcodedStreamURL?.url,
                    hlsStreamURL: hlsStreamURL,
                    streamType: streamType,
                    response: response,
                    videoStream: videoStream!,
                    audioStreams: audioStreams,
                    subtitleStreams: subtitleStreams,
                    chapters: modifiedSelfItem.chapters ?? [],
                    selectedAudioStreamIndex: defaultAudioStream?.index ?? -1,
                    selectedSubtitleStreamIndex: defaultSubtitleStream?.index ?? -1,
                    subtitlesEnabled: subtitlesEnabled,
                    autoplayEnabled: autoplayEnabled,
                    overlayType: overlayType,
                    shouldShowPlayPreviousItem: shouldShowPlayPreviousItem,
                    shouldShowPlayNextItem: shouldShowPlayNextItem,
                    shouldShowAutoPlay: shouldShowAutoPlay,
                    container: currentMediaSource.container ?? "",
                    filename: fileName,
                    versionName: currentMediaSource.name
                )

                viewModels.append(videoPlayerViewModel)
            }

            return viewModels
        }
        .eraseToAnyPublisher()
    }
}