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 { renderUnits } from "./units.js";

function escapeHtml(text) {
  return text
    .replaceAll("&", "&")
    .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;
  }
}

export function appendLog(line) {
  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) {
    state.logSource.close();
  }

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

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

        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();
        return;
      }
    } catch {
      // ignore malformed messages
    }
  };

  ws.onclose = () => {
    window.setTimeout(startPointSocket, 2000);
  };
}