/**
 * VideoKonverter TV - Video-Player v4.0
 * Fullscreen-Player mit Audio/Untertitel/Qualitaets-Auswahl,
 * Naechste-Episode-Countdown und Tastatur/Fernbedienung-Steuerung.
 */

// === State ===
let videoEl = null;
let cfg = {};           // Konfiguration aus initPlayer()
let videoInfo = null;    // Audio/Subtitle-Tracks vom Server
let currentAudio = 0;
let currentSub = -1;     // -1 = aus
let currentQuality = "hd";
let currentSpeed = 1.0;
let progressBar = null;
let timeDisplay = null;
let playBtn = null;
let controlsTimer = null;
let saveTimer = null;
let controlsVisible = true;
let overlayOpen = false;
let nextCountdown = null;
let episodesWatched = 0;
let seekOffset = 0;      // Korrektur fuer Seek-basiertes Streaming

/**
 * Player initialisieren
 * @param {Object} opts - Konfiguration
 */
function initPlayer(opts) {
    cfg = opts;
    currentQuality = opts.streamQuality || "hd";

    videoEl = document.getElementById("player-video");
    progressBar = document.getElementById("player-progress-bar");
    timeDisplay = document.getElementById("player-time");
    playBtn = document.getElementById("btn-play");

    if (!videoEl) return;

    // Video-Info laden (Audio/Subtitle-Tracks)
    loadVideoInfo().then(() => {
        // Stream starten
        setStreamUrl(opts.startPos || 0);
        updatePlayerButtons();
    });

    // Events
    videoEl.addEventListener("timeupdate", onTimeUpdate);
    videoEl.addEventListener("play", onPlay);
    videoEl.addEventListener("pause", onPause);
    videoEl.addEventListener("ended", onEnded);
    videoEl.addEventListener("loadedmetadata", () => {
        if (videoEl.duration && isFinite(videoEl.duration)) {
            cfg.duration = videoEl.duration + seekOffset;
        }
    });
    videoEl.addEventListener("click", togglePlay);

    // Controls UI
    playBtn.addEventListener("click", togglePlay);
    document.getElementById("btn-fullscreen").addEventListener("click", toggleFullscreen);
    document.getElementById("player-progress").addEventListener("click", onProgressClick);

    // Einstellungen-Button
    const btnSettings = document.getElementById("btn-settings");
    if (btnSettings) btnSettings.addEventListener("click", () => openOverlaySection(null));

    // Separate Buttons: Audio, Untertitel, Qualitaet
    const btnAudio = document.getElementById("btn-audio");
    if (btnAudio) btnAudio.addEventListener("click", () => openOverlaySection("audio"));
    const btnSubs = document.getElementById("btn-subs");
    if (btnSubs) btnSubs.addEventListener("click", () => openOverlaySection("subs"));
    const btnQuality = document.getElementById("btn-quality");
    if (btnQuality) btnQuality.addEventListener("click", () => openOverlaySection("quality"));

    // Naechste-Episode-Button
    const btnNext = document.getElementById("btn-next");
    if (btnNext) btnNext.addEventListener("click", playNextEpisode);

    // Naechste-Episode Overlay Buttons
    const btnNextPlay = document.getElementById("btn-next-play");
    if (btnNextPlay) btnNextPlay.addEventListener("click", playNextEpisode);
    const btnNextCancel = document.getElementById("btn-next-cancel");
    if (btnNextCancel) btnNextCancel.addEventListener("click", cancelNext);

    // Schaust du noch?
    const btnStillYes = document.getElementById("btn-still-yes");
    if (btnStillYes) btnStillYes.addEventListener("click", () => {
        document.getElementById("still-watching-overlay").style.display = "none";
        episodesWatched = 0;
        videoEl.play();
    });
    const btnStillNo = document.getElementById("btn-still-no");
    if (btnStillNo) btnStillNo.addEventListener("click", () => {
        saveProgress();
        window.history.back();
    });

    // Tastatur-Steuerung
    document.addEventListener("keydown", onKeyDown);
    document.addEventListener("mousemove", showControls);
    document.addEventListener("touchstart", showControls);

    scheduleHideControls();
    saveTimer = setInterval(saveProgress, 10000);
}

// === Video-Info laden ===

async function loadVideoInfo() {
    try {
        const resp = await fetch(`/api/library/videos/${cfg.videoId}/info`);
        videoInfo = await resp.json();

        // Bevorzugte Audio-Spur finden
        if (videoInfo.audio_tracks) {
            const prefIdx = videoInfo.audio_tracks.findIndex(
                a => a.lang === cfg.preferredAudio);
            if (prefIdx >= 0) currentAudio = prefIdx;
        }

        // Bevorzugte Untertitel-Spur finden
        if (cfg.subtitlesEnabled && cfg.preferredSub && videoInfo.subtitle_tracks) {
            const subIdx = videoInfo.subtitle_tracks.findIndex(
                s => s.lang === cfg.preferredSub);
            if (subIdx >= 0) currentSub = subIdx;
        }

        // Untertitel-Tracks als <track> hinzufuegen
        if (videoInfo.subtitle_tracks) {
            videoInfo.subtitle_tracks.forEach((sub, i) => {
                const track = document.createElement("track");
                track.kind = "subtitles";
                track.src = `/api/library/videos/${cfg.videoId}/subtitles/${i}`;
                track.srclang = sub.lang || "und";
                track.label = langName(sub.lang) || `Spur ${i + 1}`;
                if (i === currentSub) track.default = true;
                videoEl.appendChild(track);
            });
            // Aktiven Track setzen
            updateSubtitleTrack();
        }
    } catch (e) {
        console.warn("Video-Info laden fehlgeschlagen:", e);
    }
}

// === Stream-URL ===

function setStreamUrl(seekSec) {
    seekOffset = seekSec || 0;
    const params = new URLSearchParams({
        quality: currentQuality,
        audio: currentAudio,
        sound: cfg.soundMode || "stereo",
    });
    if (seekSec > 0) params.set("t", Math.floor(seekSec));
    const wasPlaying = videoEl && !videoEl.paused;
    videoEl.src = `/api/library/videos/${cfg.videoId}/stream?${params}`;
    if (wasPlaying) videoEl.play();
}

// === Playback-Controls ===

function togglePlay() {
    if (!videoEl) return;
    if (videoEl.paused) videoEl.play();
    else videoEl.pause();
}

function onPlay() {
    if (playBtn) playBtn.innerHTML = "&#10074;&#10074;";
    scheduleHideControls();
}

function onPause() {
    if (playBtn) playBtn.innerHTML = "&#9654;";
    showControls();
    saveProgress();
}

function onEnded() {
    saveProgress(true);
    episodesWatched++;

    // Schaust du noch? (wenn Max-Episoden erreicht)
    if (cfg.autoplayMax > 0 && episodesWatched >= cfg.autoplayMax) {
        document.getElementById("still-watching-overlay").style.display = "";
        return;
    }

    // Naechste Episode
    if (cfg.nextVideoId && cfg.autoplay) {
        showNextEpisodeOverlay();
    } else {
        setTimeout(() => window.history.back(), 2000);
    }
}

// === Seeking ===

function seekRelative(seconds) {
    if (!videoEl) return;
    const totalTime = seekOffset + videoEl.currentTime;
    const dur = cfg.duration || (seekOffset + (videoEl.duration || 0));
    const newTime = Math.max(0, Math.min(totalTime + seconds, dur));
    setStreamUrl(newTime);
    showControls();
}

function onProgressClick(e) {
    if (!videoEl) return;
    const rect = e.currentTarget.getBoundingClientRect();
    const pct = Math.max(0, Math.min(1, (e.clientX - rect.left) / rect.width));
    const dur = cfg.duration || (seekOffset + (videoEl.duration || 0));
    if (!dur) return;
    setStreamUrl(pct * dur);
    showControls();
}

// === Zeit-Anzeige ===

function onTimeUpdate() {
    if (!videoEl) return;
    const current = seekOffset + videoEl.currentTime;
    const dur = cfg.duration || (seekOffset + (videoEl.duration || 0));

    if (progressBar && dur > 0) {
        progressBar.style.width = ((current / dur) * 100) + "%";
    }
    if (timeDisplay) {
        timeDisplay.textContent = formatTime(current) + " / " + formatTime(dur);
    }
}

function formatTime(sec) {
    if (!sec || !isFinite(sec)) return "0:00";
    const h = Math.floor(sec / 3600);
    const m = Math.floor((sec % 3600) / 60);
    const s = Math.floor(sec % 60);
    if (h > 0) return h + ":" + String(m).padStart(2, "0") + ":" + String(s).padStart(2, "0");
    return m + ":" + String(s).padStart(2, "0");
}

// === Controls Ein-/Ausblenden ===

function showControls() {
    const wrapper = document.getElementById("player-wrapper");
    if (wrapper) wrapper.classList.remove("player-hide-controls");
    controlsVisible = true;
    scheduleHideControls();
}

function hideControls() {
    if (!videoEl || videoEl.paused || overlayOpen) return;
    const wrapper = document.getElementById("player-wrapper");
    if (wrapper) wrapper.classList.add("player-hide-controls");
    controlsVisible = false;
}

function scheduleHideControls() {
    if (controlsTimer) clearTimeout(controlsTimer);
    controlsTimer = setTimeout(hideControls, 4000);
}

// === Fullscreen ===

function toggleFullscreen() {
    const wrapper = document.getElementById("player-wrapper");
    if (!document.fullscreenElement) {
        (wrapper || document.documentElement).requestFullscreen().catch(() => {});
    } else {
        document.exitFullscreen().catch(() => {});
    }
}

// === Einstellungen-Overlay ===

function toggleOverlay() {
    const overlay = document.getElementById("player-overlay");
    if (!overlay) return;
    overlayOpen = !overlayOpen;
    overlay.style.display = overlayOpen ? "" : "none";
    if (overlayOpen) {
        renderOverlay();
        showControls();
        // Nur Geschwindigkeit (Audio/Subs/Qualitaet haben eigene Buttons)
        overlay.querySelectorAll(".player-overlay-section").forEach(s => {
            s.style.display = s.id === "overlay-speed" ? "" : "none";
        });
        var el = document.getElementById("overlay-speed");
        if (el) {
            var firstBtn = el.querySelector("[data-focusable]");
            if (firstBtn) firstBtn.focus();
        }
    }
}

function openOverlaySection(section) {
    const overlay = document.getElementById("player-overlay");
    if (!overlay) return;
    if (overlayOpen) {
        // Bereits offen -> schliessen
        overlayOpen = false;
        overlay.style.display = "none";
        // Alle Sektionen wieder sichtbar machen
        overlay.querySelectorAll(".player-overlay-section").forEach(
            s => s.style.display = "");
        return;
    }
    overlayOpen = true;
    overlay.style.display = "";
    renderOverlay();
    showControls();
    if (section) {
        // Nur die gewaehlte Sektion anzeigen, andere verstecken
        overlay.querySelectorAll(".player-overlay-section").forEach(s => {
            s.style.display = s.id === "overlay-" + section ? "" : "none";
        });
        var el = document.getElementById("overlay-" + section);
        if (el) {
            var firstBtn = el.querySelector("[data-focusable]");
            if (firstBtn) firstBtn.focus();
        }
    } else {
        // Settings-Button: nur Geschwindigkeit (Audio/Subs/Qualitaet haben eigene Buttons)
        overlay.querySelectorAll(".player-overlay-section").forEach(s => {
            s.style.display = s.id === "overlay-speed" ? "" : "none";
        });
        var el = document.getElementById("overlay-speed");
        if (el) {
            var firstBtn = el.querySelector("[data-focusable]");
            if (firstBtn) firstBtn.focus();
        }
    }
}

function renderOverlay() {
    // Audio-Spuren
    const audioEl = document.getElementById("overlay-audio");
    if (audioEl && videoInfo && videoInfo.audio_tracks) {
        let html = "<h3>Audio</h3>";
        videoInfo.audio_tracks.forEach((a, i) => {
            const label = langName(a.lang) || `Spur ${i + 1}`;
            const ch = a.channels > 2 ? ` (${a.channels}ch)` : "";
            const active = i === currentAudio ? " active" : "";
            html += `<button class="overlay-option${active}" data-focusable onclick="switchAudio(${i})">${label}${ch}</button>`;
        });
        audioEl.innerHTML = html;
    }

    // Untertitel
    const subsEl = document.getElementById("overlay-subs");
    if (subsEl && videoInfo) {
        let html = "<h3>Untertitel</h3>";
        html += `<button class="overlay-option${currentSub === -1 ? ' active' : ''}" data-focusable onclick="switchSub(-1)">Aus</button>`;
        if (videoInfo.subtitle_tracks) {
            videoInfo.subtitle_tracks.forEach((s, i) => {
                const label = langName(s.lang) || `Spur ${i + 1}`;
                const active = i === currentSub ? " active" : "";
                html += `<button class="overlay-option${active}" data-focusable onclick="switchSub(${i})">${label}</button>`;
            });
        }
        subsEl.innerHTML = html;
    }

    // Qualitaet
    const qualEl = document.getElementById("overlay-quality");
    if (qualEl) {
        const qualities = [
            ["uhd", "Ultra HD"], ["hd", "HD"],
            ["sd", "SD"], ["low", "Niedrig"]
        ];
        let html = "<h3>Qualit\u00e4t</h3>";
        qualities.forEach(([val, label]) => {
            const active = val === currentQuality ? " active" : "";
            html += `<button class="overlay-option${active}" data-focusable onclick="switchQuality('${val}')">${label}</button>`;
        });
        qualEl.innerHTML = html;
    }

    // Geschwindigkeit
    const speedEl = document.getElementById("overlay-speed");
    if (speedEl) {
        const speeds = [0.5, 0.75, 1.0, 1.25, 1.5, 2.0];
        let html = "<h3>Geschwindigkeit</h3>";
        speeds.forEach(s => {
            const active = s === currentSpeed ? " active" : "";
            html += `<button class="overlay-option${active}" data-focusable onclick="switchSpeed(${s})">${s}x</button>`;
        });
        speedEl.innerHTML = html;
    }
}

function switchAudio(idx) {
    if (idx === currentAudio) return;
    currentAudio = idx;
    // Neuen Stream mit anderer Audio-Spur starten
    const currentTime = seekOffset + (videoEl ? videoEl.currentTime : 0);
    setStreamUrl(currentTime);
    renderOverlay();
    updatePlayerButtons();
}

function switchSub(idx) {
    currentSub = idx;
    updateSubtitleTrack();
    renderOverlay();
    updatePlayerButtons();
}

function updateSubtitleTrack() {
    if (!videoEl || !videoEl.textTracks) return;
    for (let i = 0; i < videoEl.textTracks.length; i++) {
        videoEl.textTracks[i].mode = (i === currentSub) ? "showing" : "hidden";
    }
}

function switchQuality(q) {
    if (q === currentQuality) return;
    currentQuality = q;
    const currentTime = seekOffset + (videoEl ? videoEl.currentTime : 0);
    setStreamUrl(currentTime);
    renderOverlay();
    updatePlayerButtons();
}

function switchSpeed(s) {
    currentSpeed = s;
    if (videoEl) videoEl.playbackRate = s;
    renderOverlay();
}

// === Naechste Episode ===

function showNextEpisodeOverlay() {
    const overlay = document.getElementById("next-overlay");
    if (!overlay) return;
    overlay.style.display = "";
    let remaining = cfg.autoplayCountdown || 10;
    const countdownEl = document.getElementById("next-countdown");

    nextCountdown = setInterval(() => {
        remaining--;
        if (countdownEl) countdownEl.textContent = remaining + "s";
        if (remaining <= 0) {
            clearInterval(nextCountdown);
            playNextEpisode();
        }
    }, 1000);
    if (countdownEl) countdownEl.textContent = remaining + "s";
}

function playNextEpisode() {
    if (nextCountdown) clearInterval(nextCountdown);
    if (cfg.nextUrl) window.location.href = cfg.nextUrl;
}

function cancelNext() {
    if (nextCountdown) clearInterval(nextCountdown);
    const overlay = document.getElementById("next-overlay");
    if (overlay) overlay.style.display = "none";
    setTimeout(() => window.history.back(), 500);
}

// === D-Pad Navigation fuer Fernbedienung ===

/**
 * Fokussierbare Elemente im aktuellen Kontext finden.
 * Im Overlay: nur Overlay-Buttons. Sonst: Player-Control-Buttons.
 */
function _getFocusables() {
    if (overlayOpen) {
        const overlay = document.getElementById("player-overlay");
        return overlay ? Array.from(overlay.querySelectorAll("[data-focusable]")) : [];
    }
    // "Naechste Episode" oder "Schaust du noch" Overlay?
    const nextOv = document.getElementById("next-overlay");
    if (nextOv && nextOv.style.display !== "none") {
        return Array.from(nextOv.querySelectorAll("[data-focusable]"));
    }
    const stillOv = document.getElementById("still-watching-overlay");
    if (stillOv && stillOv.style.display !== "none") {
        return Array.from(stillOv.querySelectorAll("[data-focusable]"));
    }
    // Player-Controls
    const controls = document.getElementById("player-controls");
    return controls ? Array.from(controls.querySelectorAll("[data-focusable]")) : [];
}

function _focusNext(direction) {
    const items = _getFocusables();
    if (!items.length) return false;
    const cur = items.indexOf(document.activeElement);
    let next;
    if (direction === 1) {
        next = cur < 0 ? 0 : Math.min(cur + 1, items.length - 1);
    } else {
        next = cur < 0 ? items.length - 1 : Math.max(cur - 1, 0);
    }
    items[next].focus();
    return true;
}

// === Tastatur-Steuerung ===

function onKeyDown(e) {
    // Samsung Tizen Remote Keys
    const keyMap = {
        10009: "Escape", 10182: "Escape",
        415: "Play", 19: "Pause", 413: "Stop",
        417: "FastForward", 412: "Rewind",
        // Samsung Farbtasten
        403: "ColorRed", 404: "ColorGreen",
        405: "ColorYellow", 406: "ColorBlue",
    };
    const key = keyMap[e.keyCode] || e.key;

    const active = document.activeElement;
    const buttonFocused = active && active.hasAttribute("data-focusable") &&
        active.tagName === "BUTTON";

    // --- Overlay offen: D-Pad navigiert im Overlay ---
    if (overlayOpen) {
        switch (key) {
            case "Escape": case "Backspace":
                toggleOverlay();
                // Focus zurueck auf Settings-Button
                const btnSettings = document.getElementById("btn-settings");
                if (btnSettings) btnSettings.focus();
                e.preventDefault(); return;
            case "ArrowUp":
                _focusNext(-1); e.preventDefault(); return;
            case "ArrowDown":
                _focusNext(1); e.preventDefault(); return;
            case "ArrowLeft":
                _focusNext(-1); e.preventDefault(); return;
            case "ArrowRight":
                _focusNext(1); e.preventDefault(); return;
            case "Enter":
                if (buttonFocused) active.click();
                e.preventDefault(); return;
        }
    }

    // --- "Naechste Episode" / "Schaust du noch" Overlay ---
    const nextOv = document.getElementById("next-overlay");
    const stillOv = document.getElementById("still-watching-overlay");
    const modalOpen = (nextOv && nextOv.style.display !== "none") ||
                      (stillOv && stillOv.style.display !== "none");
    if (modalOpen) {
        switch (key) {
            case "ArrowLeft": case "ArrowRight":
                _focusNext(key === "ArrowRight" ? 1 : -1);
                e.preventDefault(); return;
            case "Enter":
                if (buttonFocused) active.click();
                e.preventDefault(); return;
        }
    }

    // --- Controls sichtbar + Button fokussiert: D-Pad navigiert ---
    if (controlsVisible && buttonFocused) {
        switch (key) {
            case "ArrowLeft":
                _focusNext(-1); showControls(); e.preventDefault(); return;
            case "ArrowRight":
                _focusNext(1); showControls(); e.preventDefault(); return;
            case "ArrowUp":
                // Vom Button weg = Controls ausblenden, Video steuern
                active.blur(); showControls(); e.preventDefault(); return;
            case "ArrowDown":
                active.blur(); showControls(); e.preventDefault(); return;
            case "Enter":
                active.click(); showControls(); e.preventDefault(); return;
        }
    }

    // --- Standard Player-Tasten ---
    switch (key) {
        case " ": case "Play": case "Pause":
            togglePlay(); e.preventDefault(); break;
        case "Enter":
            // Kein Button fokussiert: Controls einblenden + Focus auf Play
            if (!controlsVisible) {
                showControls();
                if (playBtn) playBtn.focus();
            } else {
                togglePlay();
            }
            e.preventDefault(); break;
        case "ArrowLeft": case "Rewind":
            seekRelative(-10); showControls(); e.preventDefault(); break;
        case "ArrowRight": case "FastForward":
            seekRelative(10); showControls(); e.preventDefault(); break;
        case "ArrowUp":
            // Erster Druck: Controls + Focus auf Buttons
            if (!controlsVisible) {
                showControls();
                if (playBtn) playBtn.focus();
            } else {
                // Controls sichtbar aber kein Button fokussiert: Focus setzen
                if (playBtn) playBtn.focus();
                showControls();
            }
            e.preventDefault(); break;
        case "ArrowDown":
            if (!controlsVisible) {
                showControls();
                if (playBtn) playBtn.focus();
            } else {
                if (playBtn) playBtn.focus();
                showControls();
            }
            e.preventDefault(); break;
        case "Escape": case "Backspace": case "Stop":
            saveProgress();
            setTimeout(() => window.history.back(), 100);
            e.preventDefault(); break;
        case "f":
            toggleFullscreen(); e.preventDefault(); break;
        case "s":
            toggleOverlay(); e.preventDefault(); break;
        case "n":
            if (cfg.nextVideoId) playNextEpisode();
            e.preventDefault(); break;
        // Samsung Farbtasten: Direkt-Zugriff auf Overlay-Sektionen
        case "ColorRed":
            openOverlaySection("audio"); e.preventDefault(); break;
        case "ColorGreen":
            openOverlaySection("subs"); e.preventDefault(); break;
        case "ColorYellow":
            openOverlaySection("quality"); e.preventDefault(); break;
        case "ColorBlue":
            openOverlaySection("speed"); e.preventDefault(); break;
    }
}

// === Watch-Progress speichern ===

function saveProgress(completed) {
    if (!cfg.videoId || !videoEl) return;
    const pos = seekOffset + (videoEl.currentTime || 0);
    const dur = cfg.duration || (seekOffset + (videoEl.duration || 0));
    if (pos < 5 && !completed) return;

    fetch("/tv/api/watch-progress", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({
            video_id: cfg.videoId,
            position_sec: pos,
            duration_sec: dur,
        }),
    }).catch(() => {});
}

window.addEventListener("beforeunload", () => saveProgress());

// === Button-Status aktualisieren ===

function updatePlayerButtons() {
    // CC-Button: aktiv wenn Untertitel an
    var btnSubs = document.getElementById("btn-subs");
    if (btnSubs) btnSubs.classList.toggle("active", currentSub >= 0);
    // Quality-Badge: aktuellen Modus anzeigen
    var badge = document.getElementById("quality-badge");
    if (badge) {
        var labels = { uhd: "4K", hd: "HD", sd: "SD", low: "LD" };
        badge.textContent = labels[currentQuality] || "HD";
    }
    // Audio-Button: aktuelle Sprache anzeigen (Tooltip)
    var btnAudio = document.getElementById("btn-audio");
    if (btnAudio && videoInfo && videoInfo.audio_tracks && videoInfo.audio_tracks[currentAudio]) {
        var lang = videoInfo.audio_tracks[currentAudio].lang;
        btnAudio.title = langName(lang) || "Audio";
    }
}

// === Hilfsfunktionen ===

const LANG_NAMES = {
    deu: "Deutsch", eng: "English", fra: "Fran\u00e7ais",
    spa: "Espa\u00f1ol", ita: "Italiano", jpn: "\u65e5\u672c\u8a9e",
    kor: "\ud55c\uad6d\uc5b4", por: "Portugu\u00eas",
    rus: "\u0420\u0443\u0441\u0441\u043a\u0438\u0439",
    zho: "\u4e2d\u6587", und: "Unbekannt",
};

function langName(code) {
    return LANG_NAMES[code] || code || "";
}