// ==UserScript==
// @name         FLAC Player
// @namespace    https://tingting.app
// @version      1.0.0
// @description  在 Safari 中直接播放网页上的 FLAC 音频链接，并提供下载功能
// @author       Tingting
// @match        *://*/*
// @grant        none
// @run-at       document-end
// ==/UserScript==

(function () {
  'use strict';

  // ── 配置 ────────────────────────────────────────────────────────────────────
  const ACCENT  = '#22C55E';
  const CARD_BG = '#2c2c2e';
  const TEXT    = '#f2f2f7';
  const SUBTEXT = '#8e8e93';

  // ── 全局状态 ─────────────────────────────────────────────────────────────────
  let audioEl    = null;
  let modalEl    = null;
  let playBtnEl  = null;
  let progressEl = null;

  // ── 样式注入 ─────────────────────────────────────────────────────────────────
  function injectStyles() {
    const style = document.createElement('style');
    style.id = 'fp-styles';
    style.textContent = `
      #fp-overlay {
        position: fixed; inset: 0; z-index: 2147483647;
        background: rgba(0,0,0,0.6); backdrop-filter: blur(10px);
        display: flex; align-items: flex-end; justify-content: center;
        padding-bottom: 48px;
        animation: fp-fadein 0.2s ease;
      }
      @keyframes fp-fadein  { from { opacity: 0 } to { opacity: 1 } }
      @keyframes fp-slidein { from { transform: translateY(24px); opacity: 0 } to { transform: translateY(0); opacity: 1 } }

      #fp-card {
        background: ${CARD_BG};
        border-radius: 20px;
        padding: 20px 24px 22px;
        width: 380px;
        max-width: calc(100vw - 32px);
        box-shadow: 0 24px 64px rgba(0,0,0,0.55), 0 0 0 0.5px rgba(255,255,255,0.08);
        animation: fp-slidein 0.28s cubic-bezier(0.34,1.56,0.64,1);
        font-family: -apple-system, sans-serif;
      }

      #fp-header {
        display: flex; align-items: center; gap: 12px; margin-bottom: 18px;
      }
      #fp-icon {
        width: 46px; height: 46px; border-radius: 12px; flex-shrink: 0;
        background: linear-gradient(135deg, #1a3a28 0%, #0d2016 100%);
        display: flex; align-items: center; justify-content: center; font-size: 22px;
      }
      #fp-title-wrap { flex: 1; min-width: 0; }
      #fp-title {
        color: ${TEXT}; font-size: 14px; font-weight: 600; line-height: 1.3;
        white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
      }
      #fp-subtitle { color: ${SUBTEXT}; font-size: 12px; margin-top: 3px; }
      #fp-close {
        width: 28px; height: 28px; border-radius: 50%; flex-shrink: 0;
        background: rgba(255,255,255,0.08); border: none; cursor: pointer;
        color: ${SUBTEXT}; font-size: 14px;
        display: flex; align-items: center; justify-content: center;
        transition: background 0.15s, color 0.15s;
      }
      #fp-close:hover { background: rgba(255,255,255,0.18); color: ${TEXT}; }

      #fp-progress-wrap {
        padding: 10px 0 4px; cursor: pointer;
      }
      #fp-progress-track {
        height: 3px; background: rgba(255,255,255,0.1); border-radius: 2px;
        transition: height 0.15s, background 0.15s;
        overflow: hidden;
      }
      #fp-progress-wrap:hover #fp-progress-track { height: 5px; }
      #fp-progress-fill {
        height: 100%; width: 0%; background: ${ACCENT};
        border-radius: 2px; transition: width 0.1s linear;
      }

      #fp-time-row {
        display: flex; justify-content: space-between;
        color: ${SUBTEXT}; font-size: 11px; margin: 6px 0 18px;
        font-variant-numeric: tabular-nums;
      }

      #fp-controls { display: flex; align-items: center; gap: 14px; }

      #fp-play-btn {
        width: 46px; height: 46px; border-radius: 50%; flex-shrink: 0;
        background: ${ACCENT}; border: none; cursor: pointer;
        color: #000; font-size: 17px;
        display: flex; align-items: center; justify-content: center;
        transition: transform 0.12s, opacity 0.12s;
      }
      #fp-play-btn:hover  { transform: scale(1.07); }
      #fp-play-btn:active { transform: scale(0.93); }

      #fp-volume-wrap { flex: 1; display: flex; align-items: center; gap: 8px; }
      #fp-vol-icon { color: ${SUBTEXT}; font-size: 14px; user-select: none; }
      #fp-volume {
        flex: 1; -webkit-appearance: none; height: 3px; border-radius: 2px;
        background: rgba(255,255,255,0.12); cursor: pointer; outline: none;
      }
      #fp-volume::-webkit-slider-thumb {
        -webkit-appearance: none; width: 13px; height: 13px;
        border-radius: 50%; background: ${TEXT}; cursor: pointer;
        box-shadow: 0 1px 4px rgba(0,0,0,0.4);
      }

      #fp-download-btn {
        width: 38px; height: 38px; border-radius: 50%; flex-shrink: 0;
        background: rgba(255,255,255,0.08); border: none; cursor: pointer;
        color: ${SUBTEXT}; font-size: 18px; font-weight: 300;
        display: flex; align-items: center; justify-content: center;
        transition: background 0.15s, color 0.15s;
      }
      #fp-download-btn:hover { background: rgba(255,255,255,0.16); color: ${TEXT}; }
      #fp-download-btn.fp-loading { animation: fp-spin 0.8s linear infinite; }
      @keyframes fp-spin { to { transform: rotate(360deg); } }

      /* FLAC 链接标记 */
      a[data-fp-decorated]::after {
        content: ' ▶';
        color: ${ACCENT};
        font-size: 0.75em;
        opacity: 0.75;
        vertical-align: middle;
      }
    `;
    document.head.appendChild(style);
  }

  // ── 工具函数 ─────────────────────────────────────────────────────────────────
  function formatTime(s) {
    if (!s || isNaN(s)) return '--:--';
    const m = Math.floor(s / 60);
    return `${m}:${Math.floor(s % 60).toString().padStart(2, '0')}`;
  }

  function getFilename(url) {
    try {
      const p = new URL(url).pathname;
      return decodeURIComponent(p.split('/').pop() || 'audio.flac');
    } catch {
      return 'audio.flac';
    }
  }

  // ── 下载处理 ─────────────────────────────────────────────────────────────────
  async function downloadFile(url, filename, btn) {
    btn.classList.add('fp-loading');
    btn.textContent = '↻';
    try {
      const res = await fetch(url);
      if (!res.ok) throw new Error(`HTTP ${res.status}`);
      const blob = await res.blob();
      const blobUrl = URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.href = blobUrl; a.download = filename;
      document.body.appendChild(a); a.click(); document.body.removeChild(a);
      setTimeout(() => URL.revokeObjectURL(blobUrl), 10000);
    } catch {
      // CORS 受限时回退：创建带 download 属性的链接
      const a = document.createElement('a');
      a.href = url; a.download = filename; a.target = '_blank';
      document.body.appendChild(a); a.click(); document.body.removeChild(a);
    } finally {
      btn.classList.remove('fp-loading');
      btn.textContent = '↓';
    }
  }

  // ── 播放器 Modal ─────────────────────────────────────────────────────────────
  function openPlayer(url, linkTitle) {
    destroyPlayer();

    const filename     = getFilename(url);
    const displayTitle = (linkTitle && linkTitle.length < 80) ? linkTitle : filename;

    const overlay = document.createElement('div');
    overlay.id = 'fp-overlay';
    overlay.innerHTML = `
      <div id="fp-card">
        <div id="fp-header">
          <div id="fp-icon">🎵</div>
          <div id="fp-title-wrap">
            <div id="fp-title" title="${displayTitle}">${displayTitle}</div>
            <div id="fp-subtitle">FLAC · 无损音质</div>
          </div>
          <button id="fp-close" title="关闭 (Esc)">✕</button>
        </div>

        <div id="fp-progress-wrap" title="点击跳转">
          <div id="fp-progress-track"><div id="fp-progress-fill"></div></div>
        </div>
        <div id="fp-time-row">
          <span id="fp-current">0:00</span>
          <span id="fp-duration">--:--</span>
        </div>

        <div id="fp-controls">
          <button id="fp-play-btn" title="播放/暂停 (空格)">▶</button>
          <div id="fp-volume-wrap">
            <span id="fp-vol-icon">🔊</span>
            <input id="fp-volume" type="range" min="0" max="1" step="0.02" value="1">
          </div>
          <button id="fp-download-btn" title="下载 ${filename}">↓</button>
        </div>
      </div>
    `;
    document.body.appendChild(overlay);
    modalEl = overlay;

    // 元素引用
    progressEl     = overlay.querySelector('#fp-progress-fill');
    playBtnEl      = overlay.querySelector('#fp-play-btn');
    const currentEl  = overlay.querySelector('#fp-current');
    const durationEl = overlay.querySelector('#fp-duration');
    const progressWrap = overlay.querySelector('#fp-progress-wrap');
    const volumeEl  = overlay.querySelector('#fp-volume');
    const downloadBtn = overlay.querySelector('#fp-download-btn');

    // Audio 元素
    audioEl = new Audio(url);

    audioEl.addEventListener('loadedmetadata', () => {
      durationEl.textContent = formatTime(audioEl.duration);
    });

    audioEl.addEventListener('timeupdate', () => {
      currentEl.textContent = formatTime(audioEl.currentTime);
      if (audioEl.duration) {
        progressEl.style.width = `${(audioEl.currentTime / audioEl.duration) * 100}%`;
      }
    });

    audioEl.addEventListener('ended', () => {
      playBtnEl.textContent = '▶';
    });

    audioEl.addEventListener('error', () => {
      durationEl.textContent = '加载失败';
      playBtnEl.textContent = '✕';
      playBtnEl.disabled = true;
    });

    // 控制事件
    playBtnEl.addEventListener('click', togglePlay);

    progressWrap.addEventListener('click', (e) => {
      if (!audioEl.duration) return;
      const rect = progressWrap.getBoundingClientRect();
      audioEl.currentTime = ((e.clientX - rect.left) / rect.width) * audioEl.duration;
    });

    volumeEl.addEventListener('input', () => {
      audioEl.volume = parseFloat(volumeEl.value);
    });

    downloadBtn.addEventListener('click', () => downloadFile(url, filename, downloadBtn));

    overlay.querySelector('#fp-close').addEventListener('click', destroyPlayer);
    overlay.addEventListener('click', (e) => { if (e.target === overlay) destroyPlayer(); });
    document.addEventListener('keydown', handleKeydown);

    // 自动播放
    audioEl.play()
      .then(() => { playBtnEl.textContent = '⏸'; })
      .catch(() => { /* 自动播放被阻止，等用户点击 */ });
  }

  function togglePlay() {
    if (!audioEl) return;
    if (audioEl.paused) {
      audioEl.play();
      playBtnEl.textContent = '⏸';
    } else {
      audioEl.pause();
      playBtnEl.textContent = '▶';
    }
  }

  function destroyPlayer() {
    if (audioEl) { audioEl.pause(); audioEl.src = ''; audioEl = null; }
    if (modalEl) { modalEl.remove(); modalEl = null; }
    document.removeEventListener('keydown', handleKeydown);
  }

  function handleKeydown(e) {
    if (!modalEl) return;
    switch (e.key) {
      case 'Escape':
        destroyPlayer();
        break;
      case ' ':
        if (e.target === document.body || e.target === document.documentElement) {
          e.preventDefault();
          togglePlay();
        }
        break;
      case 'ArrowRight':
        if (audioEl) audioEl.currentTime = Math.min(audioEl.currentTime + 10, audioEl.duration || 0);
        break;
      case 'ArrowLeft':
        if (audioEl) audioEl.currentTime = Math.max(audioEl.currentTime - 10, 0);
        break;
    }
  }

  // ── 链接检测 ─────────────────────────────────────────────────────────────────
  function isFlacLink(href) {
    if (!href) return false;
    try {
      const path = new URL(href, location.href).pathname;
      return /\.flac$/i.test(path);
    } catch {
      return /\.flac(\?|#|$)/i.test(href);
    }
  }

  function decorateLink(link) {
    if (link.dataset.fpDecorated) return;
    link.dataset.fpDecorated = 'true';
    link.addEventListener('click', (e) => {
      e.preventDefault();
      e.stopPropagation();
      openPlayer(link.href, link.textContent.trim() || null);
    });
  }

  function scanLinks(root = document) {
    root.querySelectorAll('a[href]').forEach(link => {
      if (isFlacLink(link.getAttribute('href'))) decorateLink(link);
    });
  }

  function observeDOM() {
    const observer = new MutationObserver((mutations) => {
      for (const m of mutations) {
        for (const node of m.addedNodes) {
          if (node.nodeType !== 1) continue;
          if (node.tagName === 'A') {
            if (isFlacLink(node.getAttribute('href'))) decorateLink(node);
          } else if (node.querySelectorAll) {
            scanLinks(node);
          }
        }
      }
    });
    observer.observe(document.body, { childList: true, subtree: true });
  }

  // ── 启动 ─────────────────────────────────────────────────────────────────────
  injectStyles();
  scanLinks();
  observeDOM();

})();