import { hostname } from "node:os";
import { readFileSync, writeFileSync } from "node:fs";
import { join } from "node:path";

import { shell } from "electron";
import { BrowserWindow, app, ipcMain, nativeTheme } from "electron/main";
import type {
  BrowserWindow as ElectronBrowserWindow,
  WebContents as ElectronWebContents,
} from "electron/main";
import type { DesktopAccountInfo, DesktopRuntimeSessionSyncRequest } from "@geo/shared-types";

import { initAccountHealth } from "./account-health";
import { bindPublishAccount, openPublishAccountConsole } from "./account-binder";
import { installObservedGlobalFetch, registerObservedRequestRendererTarget } from "./network-observer";
import { initProcessMetricsSampler } from "./process-metrics";
import { getPlaywrightCDPPort, startHiddenPlaywrightReaper } from "./playwright-cdp";
import { registerRendererDevtoolsProxyTarget } from "./renderer-devtools-proxy";
import { onRuntimeInvalidated } from "./runtime-events";
import {
  noteRuntimeAccountBound,
  refreshRuntimeAccounts,
  releaseRuntimeSession,
  syncRuntimeSession,
  unbindRuntimeAccount,
} from "./runtime-controller";
import { createRuntimeSnapshot } from "./runtime-snapshot";
import { initScheduler } from "./scheduler";
import { initSessionRegistry } from "./session-registry";
import { initSingleInstance } from "./single-instance";
import { initTransport, listDesktopPublishTasks, retryDesktopPublishTask } from "./transport/api-client";
import { initTray } from "./tray";
import { STANDARD_USER_AGENT } from "./user-agent";
import { startHotViewReaper } from "./view-pool";

app.commandLine.appendSwitch(
  "disable-features",
  "PostQuantumKyber,EncryptedClientHello,UseDnsHttpsSvcb,UseDnsHttpsSvcbAlpn",
);
app.commandLine.appendSwitch("disable-quic");
app.commandLine.appendSwitch("disable-background-networking");
app.commandLine.appendSwitch("remote-debugging-port", String(getPlaywrightCDPPort()));
app.userAgentFallback = STANDARD_USER_AGENT;
installObservedGlobalFetch();

console.info("[desktop-main] boot", {
  electron: process.versions.electron,
  chrome: process.versions.chrome,
  node: process.versions.node,
  ua: STANDARD_USER_AGENT,
});

process.on("unhandledRejection", (reason) => {
  console.error("[desktop-main] unhandled rejection", reason);
});

process.on("uncaughtException", (error) => {
  console.error("[desktop-main] uncaught exception", error);
});

let mainWindow: ElectronBrowserWindow | null = null;
let mainRendererContents: ElectronWebContents | null = null;
let quitReleaseInFlight = false;

type WindowMode = "login" | "main";

const WINDOW_SIZES: Record<WindowMode, { width: number; height: number; resizable: boolean }> = {
  login: { width: 340, height: 540, resizable: false },
  main: { width: 1320, height: 860, resizable: true },
};

function windowModePath(): string {
  return join(app.getPath("userData"), "window-mode.json");
}

function readPersistedWindowMode(): WindowMode {
  try {
    const raw = readFileSync(windowModePath(), "utf8");
    const data = JSON.parse(raw) as { mode?: unknown };
    if (data?.mode === "main" || data?.mode === "login") {
      return data.mode;
    }
  } catch {
    // First run, missing file, or corrupt — fall through to default.
  }
  return "login";
}

function persistWindowMode(mode: WindowMode): void {
  try {
    writeFileSync(windowModePath(), JSON.stringify({ mode }), "utf8");
  } catch (err) {
    console.warn("[desktop-main] persist window mode failed", err);
  }
}

let currentWindowMode: WindowMode = "login";
let windowModeApplied = false;

function applyWindowMode(window: ElectronBrowserWindow, mode: WindowMode): void {
  const isFirstApply = !windowModeApplied;
  const sameMode = windowModeApplied && currentWindowMode === mode;

  if (!sameMode) {
    currentWindowMode = mode;
    persistWindowMode(mode);

    const target = WINDOW_SIZES[mode];
    window.setResizable(true);
    window.setMinimumSize(1, 1);
    window.setMaximumSize(0, 0);
    window.setSize(target.width, target.height, false);
    window.center();

    if (mode === "login") {
      window.setMinimumSize(target.width, target.height);
      window.setMaximumSize(target.width, target.height);
      window.setResizable(false);
    } else {
      window.setMinimumSize(800, 600);
      window.setResizable(true);
    }
  }

  windowModeApplied = true;

  if (isFirstApply || !window.isVisible()) {
    window.show();
    window.focus();
  }
}

function currentMainWindow(): ElectronBrowserWindow | null {
  if (!mainWindow) {
    return null;
  }
  if (mainWindow.isDestroyed()) {
    mainWindow = null;
    windowModeApplied = false;
    return null;
  }
  return mainWindow;
}

async function ensureMainWindow(): Promise<ElectronBrowserWindow> {
  const existing = currentMainWindow();
  if (existing) {
    return existing;
  }
  const window = await createMainWindow();
  mainWindow = window;
  return window;
}

async function revealMainWindow(): Promise<void> {
  const window = await ensureMainWindow();
  applyWindowMode(window, currentWindowMode);
}

function revealMainWindowSafely(source: string): void {
  void revealMainWindow().catch((error) => {
    console.error("[desktop-main] reveal main window failed", { source, error });
  });
}

function rendererURL(): string | null {
  return process.env.ELECTRON_RENDERER_URL ?? null;
}

function preloadPath(): string {
  return join(__dirname, "../preload/bridge.cjs");
}

async function mountRendererWebContents(window: ElectronBrowserWindow): Promise<void> {
  const contents = window.webContents;

  contents.setWindowOpenHandler(() => ({ action: "deny" }));
  registerRendererDevtoolsProxyTarget(contents);
  registerObservedRequestRendererTarget(contents);
  mainRendererContents = contents;
  window.on("closed", () => {
    if (mainRendererContents === contents) {
      mainRendererContents = null;
    }
  });

  const devServerURL = rendererURL();
  if (devServerURL) {
    await contents.loadURL(devServerURL);
    contents.openDevTools({ mode: "detach" });
    return;
  }

  await contents.loadFile(join(__dirname, "../renderer/index.html"));
}

async function createMainWindow(): Promise<ElectronBrowserWindow> {
  const initial = WINDOW_SIZES[currentWindowMode];
  const window = new BrowserWindow({
    width: initial.width,
    height: initial.height,
    show: false,
    title: "GEO Rankly Desktop",
    titleBarStyle: "hiddenInset",
    trafficLightPosition: { x: 12, y: 14 },
    backgroundColor: nativeTheme.shouldUseDarkColors ? "#15191a" : "#eaf2ff",
    webPreferences: {
      preload: preloadPath(),
      sandbox: true,
      contextIsolation: true,
      nodeIntegration: false,
    },
  });

  const fallbackReveal = setTimeout(() => {
    if (!windowModeApplied && !window.isDestroyed()) {
      applyWindowMode(window, currentWindowMode);
    }
  }, 1500);
  window.once("closed", () => {
    clearTimeout(fallbackReveal);
    if (mainWindow === window) {
      mainWindow = null;
      windowModeApplied = false;
    }
  });

  window.on("minimize", () => {
    console.warn("[desktop-main] main window minimize event", {
      at: new Date().toISOString(),
      stack: new Error("trace").stack,
    });
  });
  window.on("hide", () => {
    console.warn("[desktop-main] main window hide event", {
      at: new Date().toISOString(),
      stack: new Error("trace").stack,
    });
  });
  window.on("blur", () => {
    console.warn("[desktop-main] main window blur event", {
      at: new Date().toISOString(),
      visible: window.isVisible(),
      minimized: window.isMinimized(),
    });
  });

  await mountRendererWebContents(window);
  return window;
}

function flattenError(error: unknown): Error {
  if (error instanceof Error) {
    const copy = new Error(error.message || "ipc_handler_failed");
    copy.name = error.name;
    return copy;
  }
  return new Error(typeof error === "string" ? error : "ipc_handler_failed");
}

function safeHandle<Args extends unknown[], Result>(
  channel: string,
  handler: (...args: Args) => Promise<Result> | Result,
): void {
  ipcMain.handle(channel, async (...args) => {
    try {
      return await handler(...(args as unknown as Args));
    } catch (error) {
      throw flattenError(error);
    }
  });
}

function isSafeExternalUrl(url: string): boolean {
  try {
    const parsed = new URL(url);
    return parsed.protocol === "http:" || parsed.protocol === "https:";
  } catch {
    return false;
  }
}

function registerBridgeHandlers(): void {
  ipcMain.handle("desktop:ping", () => "pong");
  ipcMain.handle("desktop:device-info", () => ({
    device_name: hostname() || `Desktop ${process.platform}`,
    os: process.platform,
    cpu_arch: process.arch,
  }));
  ipcMain.handle("desktop:runtime-snapshot", () => createRuntimeSnapshot());
  safeHandle("desktop:bind-publish-account", async (_event, platformId: string) => {
    const account = (await bindPublishAccount(platformId)) as DesktopAccountInfo;
    noteRuntimeAccountBound(account);
    void refreshRuntimeAccounts().catch((error) => {
      console.warn("[desktop-bind] background account refresh failed", {
        message: error instanceof Error ? error.message : String(error),
      });
    });
    return account;
  });
  safeHandle("desktop:refresh-runtime-accounts", async () => {
    await refreshRuntimeAccounts();
    return null;
  });
  safeHandle(
    "desktop:open-publish-account-console",
    async (
      _event,
      account: { id: string; platform: string; platformUid: string; displayName: string },
    ) => {
      await openPublishAccountConsole(account);
      return null;
    },
  );
  safeHandle(
    "desktop:unbind-publish-account",
    async (_event, accountId: string, syncVersion: number) => {
      await unbindRuntimeAccount(accountId, syncVersion);
      return null;
    },
  );
  safeHandle("desktop:list-publish-tasks", async (_event, params?: { page?: number; page_size?: number; title?: string }) => {
    return listDesktopPublishTasks(params);
  });
  safeHandle("desktop:retry-publish-task", async (_event, taskId: string) => {
    return retryDesktopPublishTask(taskId);
  });
  safeHandle("desktop:open-external-url", async (_event, url: string) => {
    if (!isSafeExternalUrl(url)) {
      throw new Error("unsupported_external_url");
    }
    await shell.openExternal(url);
    return null;
  });
  ipcMain.handle(
    "desktop:runtime-session-sync",
    (_event, session: DesktopRuntimeSessionSyncRequest | null) => {
      syncRuntimeSession(session);
      return null;
    },
  );
  safeHandle("desktop:runtime-session-release", async (_event, revoke?: boolean) => {
    await releaseRuntimeSession({ revoke: Boolean(revoke) });
    return null;
  });
  ipcMain.handle("desktop:set-window-mode", (_event, mode: WindowMode) => {
    const window = currentMainWindow();
    if (window && (mode === "login" || mode === "main")) {
      applyWindowMode(window, mode);
    }
    return null;
  });
}

if (!initSingleInstance(() => {
  revealMainWindowSafely("single-instance");
})) {
  app.quit();
}

app.whenReady().then(async () => {
  currentWindowMode = readPersistedWindowMode();
  registerBridgeHandlers();
  await initSessionRegistry();
  initAccountHealth();
  initTransport();
  initScheduler();
  initProcessMetricsSampler();
  startHotViewReaper();
  startHiddenPlaywrightReaper();
  onRuntimeInvalidated((event) => {
    if (!mainRendererContents || mainRendererContents.isDestroyed()) {
      return;
    }
    mainRendererContents.send("desktop:runtime-invalidated", event);
  });
  await ensureMainWindow();
  initTray(() => {
    revealMainWindowSafely("tray");
  });
}).catch((error) => {
  console.error("[desktop-main] app.whenReady failed", error);
});

app.on("activate", () => {
  revealMainWindowSafely("activate");
});

app.on("window-all-closed", () => {
  if (process.platform !== "darwin") {
    app.quit();
  }
});

app.on("before-quit", (event) => {
  if (quitReleaseInFlight) {
    return;
  }

  quitReleaseInFlight = true;
  event.preventDefault();

  void Promise.race([
    releaseRuntimeSession(),
    new Promise<void>((resolve) => setTimeout(resolve, 1500)),
  ]).finally(() => {
    app.quit();
  });
});