main.js

const { app, BrowserWindow, ipcMain } = require("electron");
const path = require("path");
const schedule = require("node-schedule");
const db = require("./db");

let win;

function createWindow() {
  win = new BrowserWindow({
    width: 1000,
    height: 700,
    webPreferences: {
      preload: path.join(__dirname, "preload.js"),
      contextIsolation: true,
      nodeIntegration: false,
    },
  });

  // Dev server (React)
  win.loadURL("http://localhost:5173");
  win.webContents.openDevTools();
}

app.whenReady().then(() => {
  createWindow();

  // Re-schedule pending tasks on startup
  db.all("SELECT * FROM schedules WHERE status='pending'", [], (err, rows) => {
    if (err) {
      console.error("Failed to load tasks:", err);
      return;
    }
    if (rows?.length) {
      rows.forEach((task) => scheduleJobFromDB(task));
    }
  });

  app.on("activate", () => {
    if (BrowserWindow.getAllWindows().length === 0) createWindow();
  });
});

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

/* ---------------- IPC HANDLERS ---------------- */

// 1. Schedule new task
ipcMain.handle("schedule-task", async (_, { task, runAt }) => {
  return new Promise((resolve, reject) => {
    db.run(
      "INSERT INTO schedules (task, runAt, status) VALUES (?, ?, ?)",
      [task, runAt, "pending"],
      function (err) {
        if (err) {
          console.error("Failed to insert task:", err);
          return reject(err);
        }

        const newTask = { id: this.lastID, task, runAt, status: "pending" };
        scheduleJobFromDB(newTask);
        resolve(newTask);
      }
    );
  });
});

// 2. Get all tasks
ipcMain.handle("get-tasks", async () => {
  return new Promise((resolve, reject) => {
    db.all("SELECT * FROM schedules ORDER BY runAt ASC", [], (err, rows) => {
      if (err) {
        console.error("Failed to fetch tasks:", err);
        return reject(err);
      }
      resolve(rows);
    });
  });
});

/* ---------------- Helper ---------------- */

function scheduleJobFromDB(task) {
  const runDate = new Date(task.runAt);

  if (isNaN(runDate.getTime())) {
    console.error("Invalid date for task:", task);
    return;
  }

  schedule.scheduleJob(runDate, () => {
    db.run("UPDATE schedules SET status='done' WHERE id=?", [task.id], (err) => {
      if (err) console.error("Failed to update task:", err);
    });

    if (win?.webContents) {
      win.webContents.send("task-executed", task);
    }
  });
}