import { appendChartPoint } from "./chart.js";
import { dom } from "./dom.js";
import { prependEvent } from "./events.js";
import { formatValue } from "./points.js";
import { state } from "./state.js";
import { loadUnits, renderUnits } from "./units.js";
import { loadEquipments } from "./equipment.js";
import { showToast } from "./api.js";

function escapeHtml(text) {
  return text.replaceAll("&", "&amp;").replaceAll("<", "&lt;").replaceAll(">", "&gt;");
}

function parseLogLine(line) {
  const trimmed = line.trim();
  if (!trimmed.startsWith("{") || !trimmed.endsWith("}")) return null;
  try { return JSON.parse(trimmed); } catch { return null; }
}

function appendLog(line) {
  if (!dom.logView) return;
  const atBottom = dom.logView.scrollTop + dom.logView.clientHeight >= dom.logView.scrollHeight - 10;
  const div = document.createElement("div");
  const parsed = parseLogLine(line);
  if (!parsed) {
    div.className = "log-line";
    div.textContent = line;
  } else {
    const levelRaw = (parsed.level || "").toString();
    const level = levelRaw.toLowerCase();
    div.className = `log-line${level ? ` level-${level}` : ""}`;
    div.innerHTML = [
      `<span class="level">${escapeHtml(levelRaw || "LOG")}</span>`,
      parsed.timestamp ? `<span class="muted"> ${escapeHtml(parsed.timestamp)}</span>` : "",
      parsed.target ? `<span class="muted"> ${escapeHtml(parsed.target)}</span>` : "",
      `<span class="message">${escapeHtml(parsed.fields?.message || parsed.message || parsed.msg || line)}</span>`,
    ].join("");
  }
  dom.logView.appendChild(div);
  if (atBottom) dom.logView.scrollTop = dom.logView.scrollHeight;
}

export function startLogs() {
  if (state.logSource) return;
  state.logSource = new EventSource("/api/logs/stream");
  state.logSource.addEventListener("log", (event) => {
    const data = JSON.parse(event.data);
    (data.lines || []).forEach(appendLog);
  });
  state.logSource.addEventListener("error", () => appendLog("[log stream error]"));
}

export function stopLogs() {
  if (state.logSource) {
    state.logSource.close();
    state.logSource = null;
  }
}

let _disconnectToast = null;

function setWsStatus(connected) {
  if (dom.wsDot) {
    dom.wsDot.className = `ws-dot ${connected ? "connected" : "disconnected"}`;
  }
  if (dom.wsLabel) {
    dom.wsLabel.textContent = connected ? "已连接" : "连接断开，重连中…";
  }
  if (!connected && !_disconnectToast) {
    _disconnectToast = showToast("后端连接断开", {
      message: "正在重连，请稍候…",
      level: "error",
      duration: 0,
      shake: true,
    });
  } else if (connected && _disconnectToast) {
    _disconnectToast.dismiss();
    _disconnectToast = null;
    showToast("连接已恢复", { level: "success", duration: 3000 });
  }
}

let _reconnectDelay = 1000;
let _connectedOnce = false;

export function startPointSocket() {
  const protocol = location.protocol === "https:" ? "wss" : "ws";
  const ws = new WebSocket(`${protocol}://${location.host}/ws/public`);
  state.pointSocket = ws;

  ws.onopen = () => {
    setWsStatus(true);
    _reconnectDelay = 1000;
    if (_connectedOnce) {
      loadUnits().catch(() => {});
      if (state.activeView === "config") loadEquipments().catch(() => {});
    }
    _connectedOnce = true;
  };

  ws.onmessage = (event) => {
    try {
      const payload = JSON.parse(event.data);
      if (payload.type === "PointNewValue" || payload.type === "point_new_value") {
        const data = payload.data;

        // config view point table
        const entry = state.pointEls.get(data.point_id);
        if (entry) {
          entry.value.textContent = formatValue(data);
          entry.quality.className = `badge quality-${(data.quality || "unknown").toLowerCase()}`;
          entry.quality.textContent = (data.quality || "unknown").toUpperCase();
          entry.time.textContent = data.timestamp || "--";
        }

        // ops view signal dot
        const opsEntry = state.opsPointEls.get(data.point_id);
        if (opsEntry) {
          const { dotEl } = opsEntry;
          const role = dotEl.dataset.opsRole;
          import("./ops.js").then(({ sigDotClass }) => {
            dotEl.className = sigDotClass(role, data.quality, data.value_text);
          });
        }

        if (state.chartPointId === data.point_id) {
          appendChartPoint(data);
        }
        return;
      }

      if (payload.type === "EventCreated" || payload.type === "event_created") {
        prependEvent(payload.data);
      }

      if (payload.type === "UnitRuntimeChanged") {
        const runtime = payload.data;
        state.runtimes.set(runtime.unit_id, runtime);
        renderUnits();
        // lazy import to avoid circular dep (ops.js -> logs.js -> ops.js)
        import("./ops.js").then(({ renderOpsUnits, syncEquipmentButtonsForUnit }) => {
          renderOpsUnits();
          syncEquipmentButtonsForUnit(runtime.unit_id, runtime.auto_enabled);
        });
        return;
      }
    } catch {
      // ignore malformed messages
    }
  };

  ws.onclose = () => {
    setWsStatus(false);
    window.setTimeout(startPointSocket, _reconnectDelay);
    _reconnectDelay = Math.min(_reconnectDelay * 2, 30000);
  };

  ws.onerror = () => setWsStatus(false);
}