/**
 * 音乐播放器 - HTML5 Audio API
 */
(function() {
    'use strict';

    const SONGS = window.SITE_DATA ? window.SITE_DATA.songs : [];
    let playlist = [...SONGS];
    let currentIndex = -1;
    let playMode = localStorage.getItem('playMode') || 'sequence';
    let volume = parseFloat(localStorage.getItem('volume')) || 0.8;
    let muted = false;

    const audio = document.getElementById('audioElement');
    if (!audio) return;

    // --- 封面路径处理（新增）---
    // 根据你的目录结构，封面存放在根目录 covers/ 下
    function getCoverUrl(cover) {
        const DEFAULT_COVER = 'assets/images/default-cover.svg';
        if (!cover) return DEFAULT_COVER;
        if (cover.startsWith('http')) return cover;
        if (cover.includes('/')) return cover;
        return 'covers/' + cover;
    }

    // --- DOM Elements ---
    const btnPlay = document.getElementById('btnPlay');
    const btnPrev = document.getElementById('btnPrev');
    const btnNext = document.getElementById('btnNext');
    const btnShuffle = document.getElementById('btnShuffle');
    const btnRepeat = document.getElementById('btnRepeat');
    const btnMute = document.getElementById('btnMute');
    const btnPlaylist = document.getElementById('btnPlaylist');
    const playerEl = document.getElementById('player');
    const playerTitle = document.getElementById('playerTitle');
    const playerArtist = document.getElementById('playerArtist');
    const playerCover = document.getElementById('playerCover');
    const timeCurrent = document.getElementById('timeCurrent');
    const timeTotal = document.getElementById('timeTotal');
    const progressBar = document.getElementById('progressBar');
    const progressFill = document.getElementById('progressFill');
    const progressThumb = document.getElementById('progressThumb');
    const volumeBar = document.getElementById('volumeBar');
    const volumeFill = document.getElementById('volumeFill');
    const playlistDrawer = document.getElementById('playlistDrawer');
    const drawerBody = document.getElementById('drawerBody');
    const drawerOverlay = document.getElementById('drawerOverlay');
    const drawerClose = document.getElementById('drawerClose');
    const bgGlow = document.getElementById('bgGlow');
    const playerBgGlow = document.getElementById('playerBgGlow');
    const heroDisc = document.querySelector('.hero-disc');

    // --- Storage Helpers ---
    const Store = {
        get(key, def) {
            try { const v = localStorage.getItem(key); return v !== null ? JSON.parse(v) : def; }
            catch(e) { return def; }
        },
        set(key, val) {
            try { localStorage.setItem(key, JSON.stringify(val)); } catch(e) {}
        }
    };

    let favorites = Store.get('favorites', []);
    let recent = Store.get('recent', []);

    // --- Core Functions ---
    function loadSong(index, autoplay) {
        if (index < 0 || index >= playlist.length) return;
        currentIndex = index;
        const song = playlist[index];
        audio.src = song.file;
        audio.load();

        playerTitle.textContent = song.title || '未知歌曲';
        playerArtist.textContent = song.artist || '--';
        // 【修改】使用 getCoverUrl
        playerCover.src = getCoverUrl(song.cover);

        playerEl.classList.add('active');
        updatePlayingUI(song);
        // 【修改】使用 getCoverUrl
        updateBackground(getCoverUrl(song.cover));
        updateDrawerActive();
        Store.set('currentSong', { id: song.id, file: song.file });

        if (autoplay) play();

        // Record recent
        recent = recent.filter(id => id !== song.id);
        recent.unshift(song.id);
        if (recent.length > 50) recent = recent.slice(0, 50);
        Store.set('recent', recent);

        // Update play count via API
        fetch('api/data.php?action=play_count&id=' + song.id, { method: 'GET' }).catch(()=>{});
    }

    function play() {
        audio.play().catch(()=>{});
    }

    function pause() { audio.pause(); }

    function togglePlay() {
        if (audio.paused) {
            if (!audio.src && playlist.length > 0) {
                loadSong(0, true);
            } else {
                play();
            }
        } else {
            pause();
        }
    }

    function next() {
        if (playMode === 'shuffle') {
            let idx;
            do { idx = Math.floor(Math.random() * playlist.length); }
            while (idx === currentIndex && playlist.length > 1);
            loadSong(idx, true);
        } else {
            let idx = currentIndex + 1;
            if (idx >= playlist.length) idx = 0;
            loadSong(idx, true);
        }
    }

    function prev() {
        if (audio.currentTime > 3) {
            audio.currentTime = 0;
            return;
        }
        let idx = currentIndex - 1;
        if (idx < 0) idx = playlist.length - 1;
        loadSong(idx, true);
    }

    function onEnded() {
        if (playMode === 'repeat') {
            audio.currentTime = 0;
            play();
        } else {
            next();
        }
    }

    // --- UI Updates ---
    function updatePlayingUI(song) {
        document.querySelectorAll('.music-card.playing, .song-item.playing, .drawer-song.playing').forEach(el => {
            el.classList.remove('playing');
        });
        document.querySelectorAll('[data-song-id="' + song.id + '"]').forEach(el => {
            el.classList.add('playing');
        });
    }

    function updateBackground(coverUrl) {
        if (!coverUrl || coverUrl.indexOf('default-cover') > -1) return;
        if (bgGlow) {
            bgGlow.style.background = 'radial-gradient(ellipse 60% 50% at 70% 30%, rgba(60,60,60,0.3), transparent 70%), url(' + coverUrl + ')';
            bgGlow.style.backgroundSize = 'cover, cover';
            bgGlow.style.backgroundPosition = 'center, center';
            bgGlow.style.filter = 'blur(80px)';
            bgGlow.style.opacity = '0.3';
        }
    }

    function updatePlayButton() {
        const iconsPlay = document.querySelectorAll('.icon-play');
        const iconsPause = document.querySelectorAll('.icon-pause');
        if (audio.paused) {
            iconsPlay.forEach(el => el.style.display = '');
            iconsPause.forEach(el => el.style.display = 'none');
            if (heroDisc) heroDisc.classList.remove('playing');
        } else {
            iconsPlay.forEach(el => el.style.display = 'none');
            iconsPause.forEach(el => el.style.display = '');
            if (heroDisc) heroDisc.classList.add('playing');
        }
    }

    function updateProgress() {
        const cur = audio.currentTime || 0;
        const dur = audio.duration || 0;
        const pct = dur > 0 ? (cur / dur) * 100 : 0;
        if (progressFill) progressFill.style.width = pct + '%';
        if (progressThumb) progressThumb.style.left = pct + '%';
        if (timeCurrent) timeCurrent.textContent = fmtTime(cur);
        if (timeTotal) timeTotal.textContent = fmtTime(dur);

        const mobileFill = document.getElementById('progressFillMobile');
        if (mobileFill) mobileFill.style.width = pct + '%';

        if (cur > 0) {
            Store.set('playPos', cur);
        }
    }

    function fmtTime(sec) {
        if (!sec || isNaN(sec)) return '0:00';
        const m = Math.floor(sec / 60);
        const s = Math.floor(sec % 60);
        return m + ':' + (s < 10 ? '0' : '') + s;
    }

    function setVolume(v) {
        volume = Math.max(0, Math.min(1, v));
        audio.volume = muted ? 0 : volume;
        if (volumeFill) volumeFill.style.width = (volume * 100) + '%';
        Store.set('volume', volume);
        updateMuteIcon();
    }

    function updateMuteIcon() {
        const vol = document.querySelector('.icon-vol');
        const mut = document.querySelector('.icon-mute');
        if (muted || volume === 0) {
            if (vol) vol.style.display = 'none';
            if (mut) mut.style.display = '';
        } else {
            if (vol) vol.style.display = '';
            if (mut) mut.style.display = 'none';
        }
    }

    function updateModeUI() {
        if (btnShuffle) btnShuffle.classList.toggle('active', playMode === 'shuffle');
        if (btnRepeat) btnRepeat.classList.toggle('active', playMode === 'repeat');
    }

    // --- Progress Bar Drag ---
    let dragging = false;
    function seekTo(e) {
        const rect = progressBar.getBoundingClientRect();
        const pct = Math.max(0, Math.min(1, (e.clientX - rect.left) / rect.width));
        if (audio.duration) {
            audio.currentTime = pct * audio.duration;
        }
    }
    if (progressBar) {
        progressBar.addEventListener('mousedown', function(e) {
            dragging = true;
            seekTo(e);
        });
        document.addEventListener('mousemove', function(e) {
            if (dragging) seekTo(e);
        });
        document.addEventListener('mouseup', function() { dragging = false; });
        progressBar.addEventListener('touchstart', function(e) {
            dragging = true;
            const t = e.touches[0];
            seekTo({ clientX: t.clientX });
        }, { passive: true });
        document.addEventListener('touchmove', function(e) {
            if (dragging) {
                const t = e.touches[0];
                seekTo({ clientX: t.clientX });
            }
        }, { passive: true });
        document.addEventListener('touchend', function() { dragging = false; });
    }

    // --- Volume Bar Drag ---
    let volDragging = false;
    function volSeek(e) {
        const rect = volumeBar.getBoundingClientRect();
        const pct = Math.max(0, Math.min(1, (e.clientX - rect.left) / rect.width));
        muted = false;
        setVolume(pct);
    }
    if (volumeBar) {
        volumeBar.addEventListener('mousedown', function(e) { volDragging = true; volSeek(e); });
        document.addEventListener('mousemove', function(e) { if (volDragging) volSeek(e); });
        document.addEventListener('mouseup', function() { volDragging = false; });
    }

    // --- Playlist Drawer ---
    function renderPlaylist() {
        if (!drawerBody) return;
        let html = '';
        playlist.forEach((song, i) => {
            const isPlaying = i === currentIndex;
            // 【修改】使用 getCoverUrl
            html += '<div class="drawer-song' + (isPlaying ? ' playing' : '') + '" data-index="' + i + '">';
            html += '<img src="' + getCoverUrl(song.cover) + '" alt="">';
            html += '<div class="drawer-song-info">';
            html += '<div class="drawer-song-title">' + escHtml(song.title) + '</div>';
            html += '<div class="drawer-song-artist">' + escHtml(song.artist) + '</div>';
            html += '</div></div>';
        });
        drawerBody.innerHTML = html;
        drawerBody.querySelectorAll('.drawer-song').forEach(el => {
            el.addEventListener('click', function() {
                const idx = parseInt(this.dataset.index);
                loadSong(idx, true);
            });
        });
    }

    function openDrawer() {
        if (playlistDrawer) playlistDrawer.classList.add('open');
        if (drawerOverlay) drawerOverlay.classList.add('show');
        renderPlaylist();
    }
    function closeDrawer() {
        if (playlistDrawer) playlistDrawer.classList.remove('open');
        if (drawerOverlay) drawerOverlay.classList.remove('show');
    }

    function updateDrawerActive() {
        if (!playlistDrawer || !playlistDrawer.classList.contains('open')) return;
        renderPlaylist();
    }

    // --- Favorites ---
    window.toggleFav = function(songId, btn) {
        songId = parseInt(songId);
        const idx = favorites.indexOf(songId);
        if (idx > -1) {
            favorites.splice(idx, 1);
            if (btn) btn.classList.remove('fav-active');
        } else {
            favorites.push(songId);
            if (btn) btn.classList.add('fav-active');
        }
        Store.set('favorites', favorites);
    };

    window.isFav = function(songId) {
        return favorites.indexOf(parseInt(songId)) > -1;
    };

    // --- Public API ---
    window.MusicPlayer = {
        playSongById(id) {
            const idx = playlist.findIndex(s => s.id == id);
            if (idx > -1) {
                loadSong(idx, true);
            }
        },
        playSongByIndex(idx) {
            if (idx >= 0 && idx < playlist.length) {
                loadSong(idx, true);
            }
        },
        setPlaylist(songs) {
            playlist = songs;
        },
        getCurrentSong() {
            return currentIndex >= 0 ? playlist[currentIndex] : null;
        },
        togglePlay,
        next,
        prev
    };

    // --- Helper ---
    function escHtml(str) {
        const d = document.createElement('div');
        d.textContent = str || '';
        return d.innerHTML;
    }

    // --- Event Listeners ---
    if (btnPlay) btnPlay.addEventListener('click', togglePlay);
    if (btnPrev) btnPrev.addEventListener('click', prev);
    if (btnNext) btnNext.addEventListener('click', next);
    if (btnShuffle) {
        btnShuffle.addEventListener('click', function() {
            playMode = playMode === 'shuffle' ? 'sequence' : 'shuffle';
            localStorage.setItem('playMode', playMode);
            updateModeUI();
        });
    }
    if (btnRepeat) {
        btnRepeat.addEventListener('click', function() {
            playMode = playMode === 'repeat' ? 'sequence' : 'repeat';
            localStorage.setItem('playMode', playMode);
            updateModeUI();
        });
    }
    if (btnMute) {
        btnMute.addEventListener('click', function() {
            muted = !muted;
            audio.volume = muted ? 0 : volume;
            updateMuteIcon();
        });
    }
    if (btnPlaylist) btnPlaylist.addEventListener('click', openDrawer);
    if (drawerClose) drawerClose.addEventListener('click', closeDrawer);
    if (drawerOverlay) drawerOverlay.addEventListener('click', closeDrawer);

    // Mobile controls
    const btnPlayMobile = document.getElementById('btnPlayMobile');
    const btnPrevMobile = document.getElementById('btnPrevMobile');
    const btnNextMobile = document.getElementById('btnNextMobile');
    const btnPlaylistMobile = document.getElementById('btnPlaylistMobile');
    const progressBarMobile = document.getElementById('progressBarMobile');
    if (btnPlayMobile) btnPlayMobile.addEventListener('click', togglePlay);
    if (btnPrevMobile) btnPrevMobile.addEventListener('click', prev);
    if (btnNextMobile) btnNextMobile.addEventListener('click', next);
    if (btnPlaylistMobile) btnPlaylistMobile.addEventListener('click', openDrawer);
    if (progressBarMobile) {
        progressBarMobile.addEventListener('click', function(e) {
            const rect = this.getBoundingClientRect();
            const pct = Math.max(0, Math.min(1, (e.clientX - rect.left) / rect.width));
            if (audio.duration) audio.currentTime = pct * audio.duration;
        });
    }

    audio.addEventListener('play', updatePlayButton);
    audio.addEventListener('pause', updatePlayButton);
    audio.addEventListener('timeupdate', updateProgress);
    audio.addEventListener('loadedmetadata', updateProgress);
    audio.addEventListener('ended', onEnded);

    // --- Init ---
    setVolume(volume);
    updateModeUI();

    // Restore last session
    const lastSong = Store.get('currentSong', null);
    if (lastSong && lastSong.id) {
        const idx = playlist.findIndex(s => s.id == lastSong.id);
        if (idx > -1) {
            currentIndex = idx;
            const song = playlist[idx];
            audio.src = song.file;
            audio.load();
            playerTitle.textContent = song.title || '未知歌曲';
            playerArtist.textContent = song.artist || '--';
            // 【修改】使用 getCoverUrl
            playerCover.src = getCoverUrl(song.cover);
            playerEl.classList.add('active');
            updateBackground(getCoverUrl(song.cover));

            const pos = Store.get('playPos', 0);
            if (pos > 0 && pos < (audio.duration || 99999)) {
                audio.addEventListener('loadedmetadata', function() {
                    audio.currentTime = pos;
                }, { once: true });
            }
        }
    }

    // Auto-scan on load
    fetch('api/scan.php', { method: 'GET' }).then(r => r.json()).then(data => {
        if (data && data.new_count > 0) {
            location.reload();
        }
    }).catch(()=>{});

})();