// GitLab Webhook Dashboard - 前端逻辑
// 数据源:
//   GET /api/queue    -> { pending: [], current: { task, startedAt, log } | null }
//   GET /api/history  -> { scripts: [], history: { scriptPath: [record, ...] } }

const POLL_QUEUE_MS = 1500;     // 队列 + 当前执行 轮询周期
const POLL_HISTORY_MS = 4000;   // 历史 轮询周期
const LOG_TAIL_CHARS = 12000;   // 前端日志渲染尾部最大字符数

const state = {
  pending: [],
  current: null,
  history: {},          // { scriptPath: [record, ...] }
  scripts: [],          // 配置中的全部脚本
  autoscroll: true,
  expandedLogs: new Set(),   // 已展开的历史日志 record ID（re-render 后恢复）
  lastLiveKey: null,         // 上次渲染的"当前任务身份"（用于判断是否需要重建 DOM）
};

// ============ Helpers ============
const $ = (sel) => document.querySelector(sel);
const fmtTime = (iso) => {
  if (!iso) return "-";
  const d = new Date(iso);
  if (isNaN(d.getTime())) return iso;
  const pad = (n) => String(n).padStart(2, "0");
  return `${pad(d.getHours())}:${pad(d.getMinutes())}:${pad(d.getSeconds())}`;
};
const fmtFullTime = (iso) => {
  if (!iso) return "-";
  const d = new Date(iso);
  if (isNaN(d.getTime())) return iso;
  const pad = (n) => String(n).padStart(2, "0");
  return `${d.getFullYear()}-${pad(d.getMonth() + 1)}-${pad(d.getDate())} ` +
    `${pad(d.getHours())}:${pad(d.getMinutes())}:${pad(d.getSeconds())}`;
};
const shortCommit = (s) => {
  if (!s) return "unknown";
  return s.length > 7 ? s.slice(0, 7) : s;
};
const escapeHtml = (s) =>
  String(s ?? "").replace(/[&<>"']/g, (c) => ({
    "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;", "'": "&#39;",
  }[c]));

// ============ Connection status ============
function setConn(ok, text) {
  const dot = $("#conn-dot");
  const txt = $("#conn-text");
  dot.classList.remove("dot-green", "dot-red", "dot-grey");
  dot.classList.add(ok ? "dot-green" : "dot-red");
  txt.textContent = text;
}

// ============ Fetchers ============
async function fetchJSON(url) {
  const r = await fetch(url, { cache: "no-store" });
  if (!r.ok) throw new Error(`HTTP ${r.status}`);
  return r.json();
}

async function pollQueue() {
  try {
    const data = await fetchJSON("/api/queue");
    state.pending = data.pending || [];
    state.current = data.current || null;
    setConn(true, "已连接");
    renderQueue();
    renderRunning();
  } catch (e) {
    setConn(false, "连接失败");
    console.warn("queue poll failed:", e);
  }
}

async function pollHistory() {
  try {
    const data = await fetchJSON("/api/history");
    state.scripts = data.scripts || [];
    state.history = data.history || {};
    renderHistory();
  } catch (e) {
    console.warn("history poll failed:", e);
  }
}

// ============ Renderers ============
function renderQueue() {
  const list = $("#pending-list");
  const badge = $("#pending-count");
  badge.textContent = String(state.pending.length);

  if (state.pending.length === 0) {
    list.innerHTML = `<p class="empty">暂无等待任务</p>`;
    return;
  }

  list.innerHTML = state.pending.map((p) => `
    <div class="pending-item">
      <div class="row">
        <strong>${escapeHtml(p.repo)}</strong>
        <span class="badge badge-warn">等待中</span>
      </div>
      <div class="row meta">
        <span>分支 <code>${escapeHtml(p.ref)}</code></span>
        <span>commit <code>${escapeHtml(shortCommit(p.commit))}</code></span>
      </div>
      <div class="script">${escapeHtml(p.script)}</div>
      <div class="meta">入队时间: ${escapeHtml(fmtFullTime(p.queuedAt))}</div>
    </div>
  `).join("");
}

function renderRunning() {
  const body = $("#running-body");
  const stateBadge = $("#running-state");
  const sizeEl = $("#log-size");

  if (!state.current) {
    stateBadge.textContent = "空闲";
    stateBadge.className = "badge badge-grey";
    body.innerHTML = `<p class="empty">当前没有任务在执行</p>`;
    sizeEl.textContent = "";
    state.lastLiveKey = null;
    return;
  }

  const c = state.current;
  stateBadge.textContent = "执行中";
  stateBadge.className = "badge badge-warn";

  const liveKey = `${c.task.script}|${c.task.repo}|${c.task.ref}|${c.startedAt}`;
  // 仅渲染尾部以避免长日志卡顿
  const fullLog = c.log || "";
  const tail = fullLog.length > LOG_TAIL_CHARS
    ? fullLog.slice(fullLog.length - LOG_TAIL_CHARS)
    : fullLog;

  if (state.lastLiveKey !== liveKey) {
    // 任务身份变化:重建结构并贴底
    body.innerHTML = `
      <dl class="running-meta">
        <dt>仓库</dt><dd>${escapeHtml(c.task.repo)}</dd>
        <dt>分支</dt><dd>${escapeHtml(c.task.ref)}</dd>
        <dt>Commit</dt><dd>${escapeHtml(shortCommit(c.task.commit))}</dd>
        <dt>脚本</dt><dd>${escapeHtml(c.task.script)}</dd>
        <dt>开始</dt><dd>${escapeHtml(fmtFullTime(c.startedAt))}</dd>
      </dl>
      <pre class="log-box" id="live-log"></pre>
    `;
    state.lastLiveKey = liveKey;
    const logBox = $("#live-log");
    logBox.textContent = tail || "（等待脚本输出…）";
    sizeEl.textContent = fullLog.length
      ? `${(fullLog.length / 1024).toFixed(1)} KB`
      : "";
    requestAnimationFrame(() => {
      logBox.scrollTop = logBox.scrollHeight;
    });
    return;
  }

  // 同一任务:仅更新日志内容,保持 DOM 节点稳定
  const logBox = $("#live-log");
  const distanceFromBottom = logBox.scrollHeight - logBox.scrollTop - logBox.clientHeight;
  const atBottom = distanceFromBottom <= 24;
  logBox.textContent = tail || "（等待脚本输出…）";
  sizeEl.textContent = fullLog.length
    ? `${(fullLog.length / 1024).toFixed(1)} KB`
    : "";
  if (state.autoscroll && atBottom) {
    requestAnimationFrame(() => {
      logBox.scrollTop = logBox.scrollHeight;
    });
  }
}

function statusPill(status) {
  const map = {
    success: ["status-success", "成功"],
    failed:  ["status-failed",  "失败"],
    timeout: ["status-timeout", "超时"],
    skipped: ["status-skipped", "跳过"],
    running: ["status-running", "运行中"],
  };
  const [cls, text] = map[status] || ["status-skipped", status || "-"];
  return `<span class="status-pill ${cls}"><span class="dot"></span>${text}</span>`;
}

function renderHistory() {
  const root = $("#history-list");
  if (!state.scripts.length) {
    root.innerHTML = `<p class="empty">配置文件中未声明任何脚本</p>`;
    return;
  }

  // 当前正在执行的任务 ID（用于高亮）
  const liveKey = state.current
    ? `${state.current.task.script}|${state.current.task.repo}|${state.current.task.ref}`
    : null;

  root.innerHTML = state.scripts.map((script) => {
    const records = state.history[script] || [];
    const rows = records.length
      ? records.slice().reverse().map((r) => {
          const liveMarker = (liveKey && liveKey === `${r.script}|${r.repo}|${r.ref}` && r.status === "running")
            ? "row-running"
            : "";
          const logId = `log-${r.id}`;
          return `
            <tr class="${liveMarker}">
              <td>${escapeHtml(fmtFullTime(r.startedAt))}</td>
              <td>${escapeHtml(shortCommit(r.commit))}</td>
              <td>${escapeHtml(r.repo)} <span class="muted">${escapeHtml(r.ref)}</span></td>
              <td>${statusPill(r.status)}</td>
              <td>${escapeHtml(r.duration || (r.status === "running" ? "进行中" : "-"))}</td>
              <td>${escapeHtml(r.reason || "")}</td>
              <td>
                ${r.log
                  ? `<button class="toggle-log" data-target="${logId}" data-id="${r.id}" type="button">查看日志</button>`
                  : `<span class="muted small">无日志</span>`}
              </td>
            </tr>
            ${r.log ? `
              <tr class="log-cell">
                <td colspan="7" style="padding:0;">
                  <pre class="log-box" id="${logId}" style="display:none; max-height:280px;">${escapeHtml(r.log)}</pre>
                </td>
              </tr>` : ""}
          `;
        }).join("")
      : `<tr><td colspan="7" class="empty">尚无执行记录</td></tr>`;

    return `
      <div class="history-group">
        <h3><code>${escapeHtml(script)}</code><span class="muted small">(${records.length})</span></h3>
        <table class="history-table">
          <thead>
            <tr>
              <th>开始时间</th><th>Commit</th><th>仓库/分支</th>
              <th>状态</th><th>耗时</th><th>原因</th><th>日志</th>
            </tr>
          </thead>
          <tbody>${rows}</tbody>
        </table>
      </div>
    `;
  }).join("");

  // 恢复展开状态（re-render 后保持已展开的日志）
  root.querySelectorAll(".toggle-log").forEach((btn) => {
    const expanded = state.expandedLogs.has(btn.dataset.id);
    btn.textContent = expanded ? "收起日志" : "查看日志";
    const t = document.getElementById(btn.dataset.target);
    if (t) t.style.display = expanded ? "block" : "none";
  });

  // 绑定展开日志按钮（以 state.expandedLogs 为单一事实源）
  root.querySelectorAll(".toggle-log").forEach((btn) => {
    btn.addEventListener("click", () => {
      const target = document.getElementById(btn.dataset.target);
      if (!target) return;
      const id = btn.dataset.id;
      if (state.expandedLogs.has(id)) {
        state.expandedLogs.delete(id);
        target.style.display = "none";
        btn.textContent = "查看日志";
      } else {
        state.expandedLogs.add(id);
        target.style.display = "block";
        btn.textContent = "收起日志";
      }
    });
  });
}

// ============ Wiring ============
$("#refresh-btn").addEventListener("click", () => {
  pollQueue();
  pollHistory();
});

$("#log-autoscroll").addEventListener("click", (e) => {
  state.autoscroll = !state.autoscroll;
  e.currentTarget.classList.toggle("active", state.autoscroll);
  if (state.autoscroll) {
    const logBox = $("#live-log");
    if (logBox) {
      requestAnimationFrame(() => {
        logBox.scrollTop = logBox.scrollHeight;
      });
    }
  }
});

pollQueue();
pollHistory();
setInterval(pollQueue, POLL_QUEUE_MS);
setInterval(pollHistory, POLL_HISTORY_MS);