/**
 * Video Player Component
 * Handles HLS video playback with custom controls
 */

class VideoPlayer {
    constructor() {
        this.video = document.getElementById('video-player');
        this.container = document.querySelector('.video-container');
        this.overlay = document.getElementById('player-overlay');
        this.nowPlaying = document.getElementById('now-playing');
        this.hls = null;
        this.currentChannel = null;
        this.overlayTimer = null;
        this.overlayDuration = 5000; // 5 seconds
        this.isUsingProxy = false;
        this.currentUrl = null;

        // Settings (loaded from localStorage)
        this.settings = this.loadSettings();

        this.init();
    }

    /**
     * Load settings from localStorage
     */
    loadSettings() {
        const defaults = {
            arrowKeysChangeChannel: true, // Use arrow keys for channel navigation
            overlayDuration: 5, // Seconds
            defaultVolume: 80, // 0-100
            rememberVolume: true, // Persist volume between sessions
            lastVolume: 80, // Last used volume (if rememberVolume is true)
            autoPlayNextEpisode: false // Auto-play next episode in series
        };
        try {
            const saved = localStorage.getItem('nodecast_tv_player_settings');
            if (saved) {
                return { ...defaults, ...JSON.parse(saved) };
            }
        } catch (err) {
            console.error('Error loading settings:', err);
        }
        return defaults;
    }

    /**
     * Save settings to localStorage
     */
    saveSettings() {
        try {
            localStorage.setItem('nodecast_tv_player_settings', JSON.stringify(this.settings));
        } catch (err) {
            console.error('Error saving settings:', err);
        }
    }

    /**
     * Get HLS.js configuration with buffer settings optimized for stable playback
     */
    getHlsConfig() {
        return {
            enableWorker: true,
            // Buffer settings to prevent underruns during background tab throttling
            maxBufferLength: 30,           // Buffer up to 30 seconds of content
            maxMaxBufferLength: 60,        // Absolute max buffer 60 seconds
            maxBufferSize: 60 * 1000 * 1000, // 60MB max buffer size
            // Live stream settings - stay further from live edge for stability
            liveSyncDurationCount: 3,      // Stay 3 segments behind live
            liveMaxLatencyDurationCount: 10, // Allow up to 10 segments behind before catching up
            // Faster recovery from errors
            levelLoadingMaxRetry: 4,
            manifestLoadingMaxRetry: 4,
            fragLoadingMaxRetry: 6,
            // Caption/Subtitle settings
            enableCEA708Captions: true,    // Enable CEA-708 closed captions
            enableWebVTT: true,            // Enable WebVTT subtitles
            renderTextTracksNatively: true // Use native browser rendering for text tracks
        };
    }

    init() {
        // Apply default/remembered volume
        const volume = this.settings.rememberVolume ? this.settings.lastVolume : this.settings.defaultVolume;
        this.video.volume = volume / 100;

        // Save volume changes
        this.video.addEventListener('volumechange', () => {
            if (this.settings.rememberVolume) {
                this.settings.lastVolume = Math.round(this.video.volume * 100);
                this.saveSettings();
            }
        });

        // Initialize HLS.js if supported
        if (Hls.isSupported()) {
            this.hls = new Hls(this.getHlsConfig());

            this.hls.on(Hls.Events.ERROR, (event, data) => {
                console.error('HLS error:', data);
                if (data.fatal) {
                    switch (data.type) {
                        case Hls.ErrorTypes.NETWORK_ERROR:
                            // If it's a network error and we haven't tried the proxy yet, try it
                            if (this.currentChannel && !this.isUsingProxy) {
                                console.log('Network error detected, trying via proxy...');
                                const proxiedUrl = this.getProxiedUrl(this.currentUrl);
                                this.isUsingProxy = true;
                                this.hls.loadSource(proxiedUrl);
                                this.hls.startLoad();
                            } else {
                                console.log('Network error, attempting recovery...');
                                this.hls.startLoad();
                            }
                            break;
                        case Hls.ErrorTypes.MEDIA_ERROR:
                            console.log('Media error, attempting recovery...');
                            this.hls.recoverMediaError();
                            break;
                        default:
                            this.stop();
                            break;
                    }
                }
            });

            this.hls.on(Hls.Events.MANIFEST_PARSED, () => {
                this.video.play().catch(e => console.log('Autoplay prevented:', e));
            });
        }

        // Keyboard controls
        document.addEventListener('keydown', (e) => this.handleKeyboard(e));

        // Click on video shows overlay
        this.video.addEventListener('click', () => this.showNowPlayingOverlay());
    }

    /**
     * Show the now playing overlay briefly
     */
    showNowPlayingOverlay() {
        if (!this.currentChannel) return;

        // Clear existing timer
        if (this.overlayTimer) {
            clearTimeout(this.overlayTimer);
        }

        // Show overlay
        this.nowPlaying.classList.remove('hidden');

        // Hide after duration
        this.overlayTimer = setTimeout(() => {
            this.nowPlaying.classList.add('hidden');
        }, this.settings.overlayDuration * 1000);
    }

    /**
     * Hide the now playing overlay
     */
    hideNowPlayingOverlay() {
        if (this.overlayTimer) {
            clearTimeout(this.overlayTimer);
        }
        this.nowPlaying.classList.add('hidden');
    }

    /**
     * Play a channel
     */
    async play(channel, streamUrl) {
        this.currentChannel = channel;

        try {
            // Stop current playback
            this.stop();

            // Hide "select a channel" overlay
            this.overlay.classList.add('hidden');

            // Determine if HLS or direct stream
            this.currentUrl = streamUrl;

            // Proactively use proxy for known CORS-restricted domains (like Pluto TV)
            const proxyRequiredDomains = ['pluto.tv'];
            const needsProxy = proxyRequiredDomains.some(domain => streamUrl.includes(domain));

            this.isUsingProxy = needsProxy;
            const finalUrl = needsProxy ? this.getProxiedUrl(streamUrl) : streamUrl;

            // Priority 1: Use HLS.js for all browsers that support it (Chrome, Firefox, Edge, etc.)
            if (Hls.isSupported()) {
                this.hls = new Hls(this.getHlsConfig());
                this.hls.loadSource(finalUrl);
                this.hls.attachMedia(this.video);

                this.hls.on(Hls.Events.MANIFEST_PARSED, () => {
                    this.video.play().catch(e => console.log('Autoplay prevented:', e));
                });

                // Re-attach error handler for the new Hls instance
                this.hls.on(Hls.Events.ERROR, (event, data) => {
                    if (data.fatal) {
                        if (data.type === Hls.ErrorTypes.NETWORK_ERROR && !this.isUsingProxy) {
                            console.log('CORS/Network error detected, retrying via proxy...');
                            this.isUsingProxy = true;
                            this.hls.loadSource(this.getProxiedUrl(this.currentUrl));
                            this.hls.startLoad();
                        } else {
                            console.error('Fatal HLS error:', data);
                        }
                    }
                });
            } else if (this.video.canPlayType('application/vnd.apple.mpegurl') === 'probably' ||
                this.video.canPlayType('application/vnd.apple.mpegurl') === 'maybe') {
                // Priority 2: Native HLS support (Safari on iOS/macOS where HLS.js may not work)
                this.video.src = finalUrl;
                this.video.play().catch(e => {
                    console.log('Autoplay prevented, trying proxy if CORS error:', e);
                    if (!this.isUsingProxy) {
                        this.isUsingProxy = true;
                        this.video.src = this.getProxiedUrl(streamUrl);
                        this.video.play().catch(err => console.error('Proxy play failed:', err));
                    }
                });
            } else {
                // Priority 3: Try direct playback for non-HLS streams
                this.video.src = finalUrl;
                this.video.play().catch(e => console.log('Autoplay prevented:', e));
            }

            // Update now playing info
            this.updateNowPlaying(channel);

            // Show the now playing overlay
            this.showNowPlayingOverlay();

            // Fetch EPG data for this channel
            this.fetchEpgData(channel);

            // Dispatch event
            window.dispatchEvent(new CustomEvent('channelChanged', { detail: channel }));

        } catch (err) {
            console.error('Error playing channel:', err);
            this.showError('Failed to play channel');
        }
    }

    /**
     * Fetch EPG data for current channel
     */
    async fetchEpgData(channel) {
        try {
            // First, try to use the centralized EpgGuide data (already loaded)
            if (window.app && window.app.epgGuide && window.app.epgGuide.programmes) {
                const epgGuide = window.app.epgGuide;

                // Get current program from EpgGuide
                const currentProgram = epgGuide.getCurrentProgram(channel.tvgId, channel.name);

                if (currentProgram) {
                    // Find upcoming programs from the guide's data
                    const epgChannel = epgGuide.channelMap?.get(channel.tvgId) ||
                        epgGuide.channelMap?.get(channel.name?.toLowerCase());

                    let upcoming = [];
                    if (epgChannel) {
                        const now = Date.now();
                        upcoming = epgGuide.programmes
                            .filter(p => p.channelId === epgChannel.id && new Date(p.start).getTime() > now)
                            .slice(0, 5)
                            .map(p => ({
                                title: p.title,
                                start: new Date(p.start),
                                stop: new Date(p.stop),
                                description: p.desc || ''
                            }));
                    }

                    this.updateNowPlaying(channel, {
                        current: {
                            title: currentProgram.title,
                            start: new Date(currentProgram.start),
                            stop: new Date(currentProgram.stop),
                            description: currentProgram.desc || ''
                        },
                        upcoming
                    });
                    return; // Success, exit early
                }
            }

            // Fallback: Try to get EPG from Xtream API if available
            if (channel.sourceType === 'xtream' && channel.streamId) {
                const epgData = await API.proxy.xtream.shortEpg(channel.sourceId, channel.streamId);
                if (epgData && epgData.epg_listings && epgData.epg_listings.length > 0) {
                    const listings = epgData.epg_listings;
                    const now = Math.floor(Date.now() / 1000);

                    // Find current program
                    const current = listings.find(p => {
                        const start = parseInt(p.start_timestamp);
                        const end = parseInt(p.stop_timestamp);
                        return start <= now && end > now;
                    });

                    // Get upcoming programs
                    const upcoming = listings
                        .filter(p => parseInt(p.start_timestamp) > now)
                        .slice(0, 5)
                        .map(p => ({
                            title: this.decodeBase64(p.title),
                            start: new Date(parseInt(p.start_timestamp) * 1000),
                            stop: new Date(parseInt(p.stop_timestamp) * 1000),
                            description: this.decodeBase64(p.description)
                        }));

                    if (current) {
                        this.updateNowPlaying(channel, {
                            current: {
                                title: this.decodeBase64(current.title),
                                start: new Date(parseInt(current.start_timestamp) * 1000),
                                stop: new Date(parseInt(current.stop_timestamp) * 1000),
                                description: this.decodeBase64(current.description)
                            },
                            upcoming
                        });
                    }
                }
            }
        } catch (err) {
            console.log('EPG data not available:', err.message);
        }
    }

    /**
     * Get proxied URL for a stream
     */
    getProxiedUrl(url) {
        return `/api/proxy/stream?url=${encodeURIComponent(url)}`;
    }

    /**
     * Decode base64 EPG data
     */
    decodeBase64(str) {
        if (!str) return '';
        try {
            return decodeURIComponent(escape(atob(str)));
        } catch {
            return str;
        }
    }

    /**
     * Stop playback
     */
    stop() {
        if (this.hls) {
            this.hls.destroy();
            this.hls = null;
        }
        this.video.pause();
        this.video.src = '';
        this.video.load();
    }

    /**
     * Update now playing display
     */
    updateNowPlaying(channel, epgData = null) {
        const channelName = this.nowPlaying.querySelector('.channel-name');
        const programTitle = this.nowPlaying.querySelector('.program-title');
        const programTime = this.nowPlaying.querySelector('.program-time');
        const upNextList = document.getElementById('up-next-list');

        channelName.textContent = channel.name || channel.tvgName || 'Unknown Channel';

        if (epgData && epgData.current) {
            programTitle.textContent = epgData.current.title;
            const start = new Date(epgData.current.start).toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
            const end = new Date(epgData.current.stop).toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
            programTime.textContent = `${start} - ${end}`;
        } else {
            programTitle.textContent = '';
            programTime.textContent = '';
        }

        // Update up next
        upNextList.innerHTML = '';
        if (epgData && epgData.upcoming) {
            epgData.upcoming.slice(0, 3).forEach(prog => {
                const li = document.createElement('li');
                const time = new Date(prog.start).toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
                li.textContent = `${time} - ${prog.title}`;
                upNextList.appendChild(li);
            });
        }
    }

    /**
     * Show error overlay
     */
    showError(message) {
        this.overlay.classList.remove('hidden');
        this.overlay.querySelector('.overlay-content').innerHTML = `<p style="color: var(--color-error);">${message}</p>`;
    }

    /**
     * Handle keyboard shortcuts
     */
    handleKeyboard(e) {
        if (document.activeElement.tagName === 'INPUT') return;

        switch (e.key) {
            case ' ':
            case 'k':
                e.preventDefault();
                this.video.paused ? this.video.play() : this.video.pause();
                break;
            case 'f':
                e.preventDefault();
                this.toggleFullscreen();
                break;
            case 'm':
                e.preventDefault();
                this.video.muted = !this.video.muted;
                break;
            case 'ArrowUp':
                e.preventDefault();
                if (this.settings.arrowKeysChangeChannel) {
                    this.channelUp();
                } else {
                    this.video.volume = Math.min(1, this.video.volume + 0.1);
                }
                break;
            case 'ArrowDown':
                e.preventDefault();
                if (this.settings.arrowKeysChangeChannel) {
                    this.channelDown();
                } else {
                    this.video.volume = Math.max(0, this.video.volume - 0.1);
                }
                break;
            case 'ArrowLeft':
                e.preventDefault();
                // Volume down when arrow keys are for channels
                if (this.settings.arrowKeysChangeChannel) {
                    this.video.volume = Math.max(0, this.video.volume - 0.1);
                }
                break;
            case 'ArrowRight':
                e.preventDefault();
                // Volume up when arrow keys are for channels
                if (this.settings.arrowKeysChangeChannel) {
                    this.video.volume = Math.min(1, this.video.volume + 0.1);
                }
                break;
            case 'PageUp':
            case 'ChannelUp':
                e.preventDefault();
                this.channelUp();
                break;
            case 'PageDown':
            case 'ChannelDown':
                e.preventDefault();
                this.channelDown();
                break;
            case 'i':
                // Show/hide info overlay
                e.preventDefault();
                if (this.nowPlaying.classList.contains('hidden')) {
                    this.showNowPlayingOverlay();
                } else {
                    this.hideNowPlayingOverlay();
                }
                break;
        }
    }

    /**
     * Go to previous channel
     */
    channelUp() {
        if (!window.app?.channelList) return;
        const channels = window.app.channelList.getVisibleChannels();
        if (channels.length === 0) return;

        const currentIdx = this.currentChannel
            ? channels.findIndex(c => c.id === this.currentChannel.id)
            : -1;

        const prevIdx = currentIdx <= 0 ? channels.length - 1 : currentIdx - 1;
        window.app.channelList.selectChannel({ channelId: channels[prevIdx].id });
    }

    /**
     * Go to next channel
     */
    channelDown() {
        if (!window.app?.channelList) return;
        const channels = window.app.channelList.getVisibleChannels();
        if (channels.length === 0) return;

        const currentIdx = this.currentChannel
            ? channels.findIndex(c => c.id === this.currentChannel.id)
            : -1;

        const nextIdx = currentIdx >= channels.length - 1 ? 0 : currentIdx + 1;
        window.app.channelList.selectChannel({ channelId: channels[nextIdx].id });
    }

    /**
     * Toggle fullscreen
     */
    toggleFullscreen() {
        if (document.fullscreenElement) {
            document.exitFullscreen();
        } else if (this.container) {
            this.container.requestFullscreen();
        }
    }
}

// Export
window.VideoPlayer = VideoPlayer;