// ==UserScript==
// @name         Lyra Gemini Tracker Exporter (clean + similarity streaming)
// @namespace    userscript://lyra-gemini-tracker
// @version      4
// @description  跟踪 Gemini 对话的用户编辑与回答重试，使用文本相似度区分流式更新与 retry，导出精简 JSON（无冗余字段）
// @author       Lyra
// @match        https://gemini.google.com/app/*
// @include      *://gemini.google.com/*
// @run-at       document-end
// @grant        GM_addStyle
// @downloadURL none
// ==/UserScript==

/*
  输出格式示例：
  {
    "platform": "gemini",
    "exportedAt": "2025-11-16T09:00:00.000Z",
    "turns": [
      {
        "turnIndex": 0,
        "human": {
          "versions": ["原始提问", "编辑后提问"]
        },
        "assistant": {
          "versions": [
            "第一次答案(最终文本)",
            "retry1 最终答案(最终文本)",
            "retry2 最终答案(最终文本)"
          ],
          "versionGroups": ["0", "1", "2"]
        }
      }
    ]
  }
*/

(function () {
  'use strict';
  if (window.lyraGeminiInitialized) return;
  window.lyraGeminiInitialized = true;

  /* ---------------- util ---------------- */
  const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

  /* ---------------- config ---------------- */
  const CFG = {
    PANEL_ID: 'lyra-gemini-panel',
    TOGGLE_ID: 'lyra-gemini-toggle',
    EXPORT_BTN_ID: 'lyra-gemini-export',
    SCAN_INTERVAL: 1000,
    // 仍保留时间阈值做辅助（可调），但主要靠文本相似度
    STREAM_THRESHOLD_MS: 60000,
    STREAM_RATIO: 0.7 // 短文本长度 / 长文本长度 >= 0.7 视为同一次生成
  };

  /* ---------------- tracker ---------------- */
  const Tracker = {
    turns: {}, // turnIndex -> data
    lastPath: location.pathname,
    reset() {
      this.turns = {};
    },
  };

  /* helper: 提取 turn dom 列表 */
  function queryTurns() {
    return document.querySelectorAll(
      'div.conversation-turn, div.single-turn, div.conversation-container'
    );
  }

  /* helper: 读取用户/助手文本 */
  function extractUserText(turn) {
    const el =
      turn.querySelector('user-query .query-text') ||
      turn.querySelector('.query-text-line');
    return el ? el.innerText.trim() : '';
  }

  function extractAssistantText(turn) {
    const panel =
      turn.querySelector('model-response .markdown-main-panel') ||
      turn.querySelector('.markdown-main-panel') ||
      turn.querySelector('model-response') ||
      turn.querySelector('.response-container');
    return panel ? panel.innerText.trim() : '';
  }

  /* 文本相似度：判断 newText 是否是 oldText 的“超集版本” */
  function isStreamingContinuation(oldText, newText) {
    const a = (oldText || '').trim();
    const b = (newText || '').trim();
    if (!a || !b) return false;

    let short = a;
    let long = b;
    if (short.length > long.length) {
      short = b;
      long = a;
    }

    const idx = long.indexOf(short);
    if (idx === -1) return false;

    const ratio = short.length / long.length;
    return ratio >= CFG.STREAM_RATIO;
  }

  /* 确保 turn 数据结构 */
  function ensureTurn(idx) {
    let t = Tracker.turns[idx];
    if (!t) {
      t = {
        human: {
          versions: [],
          last: '',
        },
        assistant: {
          versions: [],
          last: '',
          lastUpdate: 0,
          currentIdx: -1,
        },
      };
      Tracker.turns[idx] = t;
    }
    return t;
  }

  /* 处理 user 文本，捕捉 edit */
  function handleHuman(idx, text) {
    const t = ensureTurn(idx);
    if (!text) return;
    if (!t.human.last) {
      t.human.last = text;
      t.human.versions.push(text);
    } else if (text !== t.human.last) {
      t.human.last = text;
      t.human.versions.push(text); // 视为 edit
    }
  }

  /* 处理 assistant 文本：用相似度 + 时间辅助区分 streaming 与 retry */
  function handleAssistant(idx, text) {
    if (!text) return;
    const now = Date.now();
    const t = ensureTurn(idx);

    // 第一次
    if (!t.assistant.last) {
      t.assistant.last = text;
      t.assistant.lastUpdate = now;
      t.assistant.currentIdx = 0;
      t.assistant.versions.push(text);
      return;
    }

    // 未变更
    if (text === t.assistant.last) return;

    const delta = now - t.assistant.lastUpdate;
    const similar = isStreamingContinuation(t.assistant.last, text);
    const timeOk = delta < CFG.STREAM_THRESHOLD_MS;

    const streamingUpdate = similar && timeOk;

    if (streamingUpdate && t.assistant.currentIdx >= 0) {
      // 仍视为同一次生成过程，只覆盖当前版本，保留一个最终文本
      t.assistant.versions[t.assistant.currentIdx] = text;
      t.assistant.last = text;
      t.assistant.lastUpdate = now;
    } else {
      // 判定为真正的 retry，新建版本
      t.assistant.versions.push(text);
      t.assistant.currentIdx = t.assistant.versions.length - 1;
      t.assistant.last = text;
      t.assistant.lastUpdate = now;
    }
  }

  /* 定期扫描 dom 更新 tracker */
  function scan() {
    // conversation 切换检测
    if (location.pathname !== Tracker.lastPath) {
      Tracker.lastPath = location.pathname;
      Tracker.reset();
    }

    const turns = queryTurns();

    turns.forEach((turn, idx) => {
      handleHuman(idx, extractUserText(turn));
      handleAssistant(idx, extractAssistantText(turn));
    });
  }

  /* 构造 assistant versionGroups 数组，如 ["0", "1", "2-3"] */
  function buildGroups(arr) {
    if (arr.length === 0) return [];
    const ranges = [];
    let start = 0;
    for (let i = 1; i < arr.length; i++) {
      // assistant.versions[i] 的诞生标志 retry，因此直接断开
      ranges.push(start === i - 1 ? `${start}` : `${start}-${i - 1}`);
      start = i;
    }
    ranges.push(start === arr.length - 1 ? `${start}` : `${start}-${arr.length - 1}`);
    return ranges;
  }

  /* 构造导出 JSON */
  function buildExport() {
    scan(); // 最终扫描一次
    const turnIndices = Object.keys(Tracker.turns)
      .map((i) => parseInt(i, 10))
      .sort((a, b) => a - b);

    const turns = turnIndices.map((idx) => {
      const t = Tracker.turns[idx];
      return {
        turnIndex: idx,
        human: {
          versions: [...t.human.versions],
        },
        assistant: {
          versions: [...t.assistant.versions],
          versionGroups: buildGroups(t.assistant.versions),
        },
      };
    });

    return {
      platform: 'gemini',
      exportedAt: new Date().toISOString(),
      turns,
    };
  }

  /* 下载 json */
  function download(obj) {
    const json = JSON.stringify(obj, null, 2);
    const blob = new Blob([json], { type: 'application/json' });
    const url = URL.createObjectURL(blob);

    const a = document.createElement('a');
    const date = new Date().toISOString().slice(0, 10);
    a.href = url;
    a.download = `gemini_export_${date}.json`;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
  }

  /* ---------------- ui ---------------- */
  function injectCSS() {
    GM_addStyle(`
      #${CFG.PANEL_ID}{position:fixed;top:50%;right:0;transform:translateY(-50%) translateX(12px);background:#fff;border:1px solid #dadce0;border-radius:8px;padding:14px 14px 8px;width:140px;z-index:999999;font-family:'Segoe UI',system-ui,-apple-system,sans-serif;box-shadow:0 4px 12px rgba(0,0,0,.15);transition:all .6s cubic-bezier(.4,0,.2,1)}
      #${CFG.PANEL_ID}.collapsed{transform:translateY(-50%) translateX(calc(100% - 34px));opacity:.6;pointer-events:none}
      #${CFG.TOGGLE_ID}{position:absolute;left:0;top:50%;transform:translate(-50%,-50%);width:26px;height:26px;border-radius:50%;background:#fff;border:1px solid #dadce0;display:flex;align-items:center;justify-content:center;cursor:pointer;box-shadow:0 1px 3px rgba(0,0,0,.2);z-index:1000}
      #${CFG.PANEL_ID}.collapsed #${CFG.TOGGLE_ID}{background:#1a73e8;color:#fff;width:22px;height:22px}
      .lyra-title{font-size:15px;font-weight:700;margin-bottom:10px;text-align:center;color:#202124}
      .lyra-btn{display:flex;align-items:center;justify-content:center;width:100%;padding:8px 10px;border-radius:6px;border:none;background:#1a73e8;color:#fff;font-size:11px;font-weight:500;cursor:pointer}
      .lyra-status{margin-top:6px;font-size:10px;color:#5f6368;text-align:center}
    `);
  }

  function createPanel() {
    if (document.getElementById(CFG.PANEL_ID)) return;
    const panel = document.createElement('div');
    panel.id = CFG.PANEL_ID;

    const toggle = document.createElement('div');
    toggle.id = CFG.TOGGLE_ID;
    toggle.textContent = '<';
    toggle.addEventListener('click', () => {
      const collapsed = panel.classList.toggle('collapsed');
      toggle.textContent = collapsed ? '>' : '<';
    });

    const title = document.createElement('div');
    title.className = 'lyra-title';
    title.textContent = 'Gemini Tracker';

    const btn = document.createElement('button');
    btn.id = CFG.EXPORT_BTN_ID;
    btn.className = 'lyra-btn';
    btn.textContent = '导出 JSON';

    const status = document.createElement('div');
    status.className = 'lyra-status';

    btn.addEventListener('click', async () => {
      btn.disabled = true;
      status.textContent = '生成中…';
      await sleep(100);
      try {
        const data = buildExport();
        download(data);
        status.textContent = '已导出';
      } catch (e) {
        console.error(e);
        status.textContent = '失败: ' + e.message;
      } finally {
        await sleep(800);
        status.textContent = '';
        btn.disabled = false;
      }
    });

    panel.appendChild(toggle);
    panel.appendChild(title);
    panel.appendChild(btn);
    panel.appendChild(status);
    document.body.appendChild(panel);
  }

  /* ---------------- init ---------------- */
  function init() {
    injectCSS();
    createPanel();
    setInterval(scan, CFG.SCAN_INTERVAL);
    console.log('[LyraGemini] tracker running with similarity-based streaming detection');
  }

  if (document.readyState === 'loading') {
    window.addEventListener('DOMContentLoaded', () => setTimeout(init, 1200));
  } else {
    setTimeout(init, 1200);
  }
})();