/**
 * OpenClaw Command Center - Main Application
 *
 * Uses morphdom for efficient DOM updates (only patches what changed).
 */

// Import morphdom (loaded as UMD, available as global `morphdom`)
// <script src="/js/lib/morphdom.min.js"></script> must be loaded first

// ============================================================================
// STATE MANAGEMENT
// ============================================================================

const state = {
  vitals: null,
  sessions: [],
  tokenStats: {},
  statusCounts: { all: 0, live: 0, recent: 0, idle: 0 },
  capacity: { main: { active: 0, max: 12 }, subagent: { active: 0, max: 24 } },
  operators: { operators: [], roles: {} },
  llmUsage: null,
  cron: [],
  memory: null,
  cerebro: null,
  subagents: [],
  lastUpdated: null,
  connected: false,
};

// ============================================================================
// SSE CONNECTION
// ============================================================================

let eventSource = null;
let reconnectAttempts = 0;
const MAX_RECONNECT_DELAY = 30000;

function connectSSE() {
  if (typeof EventSource === "undefined") {
    console.warn("[SSE] Not supported, falling back to polling");
    startPolling();
    return;
  }

  updateConnectionStatus("connecting");

  eventSource = new EventSource("/api/events");

  eventSource.onopen = () => {
    console.log("[SSE] Connected");
    state.connected = true;
    reconnectAttempts = 0;
    updateConnectionStatus("connected");
  };

  eventSource.addEventListener("connected", (e) => {
    const data = JSON.parse(e.data);
    console.log("[SSE] Server greeting:", data.message);
  });

  eventSource.addEventListener("update", (e) => {
    const data = JSON.parse(e.data);
    handleStateUpdate(data);
  });

  eventSource.addEventListener("heartbeat", (e) => {
    const data = JSON.parse(e.data);
    state.lastUpdated = new Date();
    updateTimestamp();
  });

  eventSource.onerror = () => {
    console.error("[SSE] Connection error");
    state.connected = false;
    eventSource.close();
    updateConnectionStatus("disconnected");

    // Exponential backoff
    reconnectAttempts++;
    const delay = Math.min(1000 * Math.pow(2, reconnectAttempts - 1), MAX_RECONNECT_DELAY);
    console.log(`[SSE] Reconnecting in ${delay}ms`);
    setTimeout(connectSSE, delay);
  };
}

// ============================================================================
// STATE UPDATES
// ============================================================================

function handleStateUpdate(data) {
  // Merge new data into state
  if (data.vitals) state.vitals = data.vitals;
  if (data.sessions) state.sessions = data.sessions;
  if (data.tokenStats) state.tokenStats = data.tokenStats;
  if (data.statusCounts) state.statusCounts = data.statusCounts;
  if (data.capacity) state.capacity = data.capacity;
  if (data.operators) state.operators = data.operators;
  if (data.llmUsage) state.llmUsage = data.llmUsage;
  if (data.cron) state.cron = data.cron;
  if (data.memory) state.memory = data.memory;
  if (data.cerebro) state.cerebro = data.cerebro;
  if (data.subagents) state.subagents = data.subagents;

  state.lastUpdated = new Date();

  // Re-render affected components using morphdom
  renderAll();
}

// ============================================================================
// RENDERING (with morphdom)
// ============================================================================

function renderAll() {
  // Each render function generates HTML and morphdom patches the DOM
  renderVitals();
  renderTokenStats();
  renderLlmUsage();
  renderSessions();
  renderCron();
  renderMemory();
  renderCerebro();
  renderOperators();
  updateTimestamp();
}

// Utility: safely patch a container using morphdom
function patchElement(containerId, newHtml) {
  const container = document.getElementById(containerId);
  if (!container) return;

  // Create a temporary element with the new content
  const temp = document.createElement("div");
  temp.innerHTML = newHtml;

  // Use morphdom to efficiently patch only what changed
  if (typeof morphdom !== "undefined") {
    // Patch each child
    while (container.firstChild && temp.firstChild) {
      morphdom(container.firstChild, temp.firstChild);
      temp.removeChild(temp.firstChild);
    }
    // Add any new children
    while (temp.firstChild) {
      container.appendChild(temp.firstChild);
    }
    // Remove extra children
    while (container.childNodes.length > temp.childNodes.length) {
      container.removeChild(container.lastChild);
    }
  } else {
    // Fallback: direct innerHTML replacement
    container.innerHTML = newHtml;
  }
}

// ============================================================================
// COMPONENT RENDERERS (to be extracted to separate files)
// ============================================================================

function renderVitals() {
  if (!state.vitals) return;
  const v = state.vitals;

  // Update individual elements (simpler than full morphdom for now)
  setText("vitals-hostname", v.hostname || "-");
  setText("vitals-uptime", v.uptime || "-");

  if (v.cpu) {
    const cpuPct = v.cpu.usage || 0;
    setText("cpu-percent", cpuPct + "%");
    setWidth("cpu-bar", cpuPct + "%");
    setText("cpu-user", (v.cpu.userPercent?.toFixed(1) || "-") + "%");
    setText("cpu-sys", (v.cpu.sysPercent?.toFixed(1) || "-") + "%");
    setText("cpu-idle", (v.cpu.idlePercent?.toFixed(1) || "-") + "%");
    setText("cpu-chip", v.cpu.chip || v.cpu.brand || "");
  }

  if (v.memory) {
    const memPct = v.memory.percent || 0;
    setText("mem-percent", memPct + "% used");
    setWidth("mem-bar", memPct + "%");
    setText("mem-summary", `${v.memory.usedFormatted || "-"} of ${v.memory.totalFormatted || "-"}`);
  }

  if (v.disk) {
    const diskPct = v.disk.percent || 0;
    setText("disk-percent", diskPct + "% used");
    setWidth("disk-bar", diskPct + "%");
    setText("disk-summary", `${v.disk.usedFormatted || "-"} of ${v.disk.totalFormatted || "-"}`);
  }
}

function renderTokenStats() {
  if (!state.tokenStats) return;
  const t = state.tokenStats;

  setText("stat-total-tokens", t.total || "-");
  setText("stat-input", t.input || "-");
  setText("stat-output", t.output || "-");
  setText("stat-active", t.activeCount || "0");
  setText("stat-cost", t.estCost || "-");
  setText("stat-main", `${t.activeMainCount || 0}/${t.mainLimit || 12}`);
  setText("stat-subagents", `${t.activeSubagentCount || 0}/${t.subagentLimit || 24}`);
}

function renderLlmUsage() {
  // Placeholder - will be extracted to component
}

function renderSessions() {
  // Placeholder - will be extracted to component
}

function renderCron() {
  // Placeholder - will be extracted to component
}

function renderMemory() {
  // Placeholder - will be extracted to component
}

function renderCerebro() {
  // Placeholder - will be extracted to component
}

function renderOperators() {
  // Placeholder - will be extracted to component
}

// ============================================================================
// UTILITIES
// ============================================================================

function setText(id, text) {
  const el = document.getElementById(id);
  if (el && el.textContent !== text) {
    el.textContent = text;
  }
}

function setWidth(id, width) {
  const el = document.getElementById(id);
  if (el && el.style.width !== width) {
    el.style.width = width;
  }
}

function updateTimestamp() {
  const now = state.lastUpdated || new Date();
  const timeStr = now.toLocaleTimeString();
  const indicator = state.connected ? " ⚡" : "";
  setText("last-updated", timeStr + indicator);
  setText("sidebar-updated", state.connected ? `Live: ${timeStr}` : `Updated: ${timeStr}`);
}

function updateConnectionStatus(status) {
  const el = document.getElementById("connection-status");
  if (!el) return;

  el.className = "connection-status " + status;
  el.textContent =
    status === "connected"
      ? "🟢 Live"
      : status === "connecting"
        ? "🟡 Connecting..."
        : "🔴 Disconnected";
}

// ============================================================================
// POLLING FALLBACK
// ============================================================================

let pollInterval = null;

function startPolling() {
  if (pollInterval) return;
  pollInterval = setInterval(fetchState, 5000);
  fetchState();
}

async function fetchState() {
  try {
    const response = await fetch("/api/state");
    const data = await response.json();
    handleStateUpdate(data);
  } catch (e) {
    console.error("[Polling] Failed:", e);
  }
}

// ============================================================================
// INITIALIZATION
// ============================================================================

function init() {
  console.log("[App] Initializing OpenClaw Command Center");
  connectSSE();

  // Initial fetch to populate immediately
  setTimeout(fetchState, 100);
}

// Start when DOM is ready
if (document.readyState === "loading") {
  document.addEventListener("DOMContentLoaded", init);
} else {
  setTimeout(init, 0);
}