import { app, BrowserWindow, shell, dialog } from "electron";
import path from "path";
import { checkDocker, dockerDownloadUrl } from "./docker-check";
import { defaultWorkspacePath, detectNwnHome } from "./paths";

let mainWindow: BrowserWindow | null = null;
let serverPort: number;

function setEnvironment(): void {
  if (!process.env.WORKSPACE_PATH) {
    process.env.WORKSPACE_PATH = defaultWorkspacePath();
  }
  if (!process.env.NWN_HOME_PATH) {
    const detected = detectNwnHome();
    if (detected) process.env.NWN_HOME_PATH = detected;
  }
  if (!process.env.GIT_PROVIDER_URL) {
    process.env.GIT_PROVIDER_URL = "https://gitea.layonara.com";
  }
  process.env.ELECTRON = "1";
}

async function startBackend(): Promise<number> {
  const { startServer } = await import(
    path.join(__dirname, "../packages/backend/dist/index.js")
  );
  const port = await findFreePort();
  await startServer(port);
  return port;
}

function findFreePort(): Promise<number> {
  return new Promise((resolve, reject) => {
    const net = require("net");
    const srv = net.createServer();
    srv.listen(0, () => {
      const port = srv.address().port;
      srv.close(() => resolve(port));
    });
    srv.on("error", reject);
  });
}

function createWindow(port: number): BrowserWindow {
  const win = new BrowserWindow({
    width: 1280,
    height: 900,
    minWidth: 960,
    minHeight: 600,
    title: "Layonara Forge",
    icon: path.join(__dirname, "../assets/icon.png"),
    webPreferences: {
      preload: path.join(__dirname, "preload.js"),
      contextIsolation: true,
      nodeIntegration: false,
    },
  });

  win.loadURL(`http://localhost:${port}`);

  win.webContents.setWindowOpenHandler(({ url }) => {
    if (url.startsWith("http")) shell.openExternal(url);
    return { action: "deny" };
  });

  win.on("closed", () => {
    mainWindow = null;
  });

  return win;
}

async function showDockerMissing(): Promise<boolean> {
  const url = dockerDownloadUrl();
  const { response } = await dialog.showMessageBox({
    type: "warning",
    title: "Docker Required",
    message: "Layonara Forge requires Docker to build modules and run the NWN server.",
    detail: "Docker Desktop must be installed and running before using the Forge.\n\nClick \"Download Docker\" to open the download page, or \"Check Again\" after installing.",
    buttons: ["Download Docker", "Check Again", "Quit"],
    defaultId: 0,
    cancelId: 2,
  });

  if (response === 0) {
    shell.openExternal(url);
    return showDockerMissing();
  }
  if (response === 1) {
    const status = await checkDocker();
    if (status.available) return true;
    return showDockerMissing();
  }
  return false;
}

app.whenReady().then(async () => {
  setEnvironment();

  const docker = await checkDocker();
  if (!docker.available) {
    const installed = await showDockerMissing();
    if (!installed) {
      app.quit();
      return;
    }
  }

  try {
    serverPort = await startBackend();
  } catch (err: any) {
    dialog.showErrorBox(
      "Forge Startup Error",
      `Failed to start the backend server:\n\n${err.message}`,
    );
    app.quit();
    return;
  }

  mainWindow = createWindow(serverPort);
});

app.on("window-all-closed", () => {
  app.quit();
});

app.on("activate", () => {
  if (mainWindow === null && serverPort) {
    mainWindow = createWindow(serverPort);
  }
});