const { app, BrowserWindow, ipcMain, dialog, shell } = require('electron');
const path = require('path');
const fs = require('fs');

let mainWindow;

function createWindow() {
  mainWindow = new BrowserWindow({
    width: 1200,
    height: 820,
    minWidth: 900,
    minHeight: 600,
    titleBarStyle: 'hiddenInset',
    backgroundColor: '#0f0f17',
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
    },
    show: false,
  });

  mainWindow.loadFile(path.join(__dirname, 'index.html'));

  mainWindow.once('ready-to-show', () => {
    mainWindow.show();
  });
}

app.whenReady().then(createWindow);

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

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

// ── IPC 핸들러 ──────────────────────────────────────

ipcMain.handle('select-folder', async () => {
  const result = await dialog.showOpenDialog(mainWindow, {
    properties: ['openDirectory'],
    title: '이미지 폴더 선택',
  });
  if (result.canceled) return null;
  return result.filePaths[0];
});

ipcMain.handle('list-images', async (_event, folderPath) => {
  const EXTS = new Set(['.jpg', '.jpeg', '.png', '.gif', '.bmp', '.tiff', '.tif', '.webp', '.heic', '.heif']);
  try {
    const files = fs.readdirSync(folderPath)
      .filter(f => EXTS.has(path.extname(f).toLowerCase()))
      .map(f => {
        const fullPath = path.join(folderPath, f);
        const stat = fs.statSync(fullPath);
        return { name: f, path: fullPath, mtime: stat.mtimeMs, size: stat.size };
      })
      .sort((a, b) => a.name.localeCompare(b.name, 'ko'));
    return files;
  } catch (e) {
    return [];
  }
});

ipcMain.handle('read-image', async (_event, filePath) => {
  try {
    const data = fs.readFileSync(filePath);
    const ext = path.extname(filePath).toLowerCase().replace('.', '');
    const mime = (ext === 'jpg' || ext === 'jpeg') ? 'jpeg'
               : ext === 'png'  ? 'png'
               : ext === 'gif'  ? 'gif'
               : ext === 'webp' ? 'webp'
               : 'jpeg';
    return `data:image/${mime};base64,${data.toString('base64')}`;
  } catch (e) {
    return null;
  }
});

ipcMain.handle('rename-files', async (_event, { folderPath, files, prefix, digits }) => {
  const errors = [];
  const pad = (n) => String(n + 1).padStart(digits, '0');

  // 1단계: 임시 이름으로 이동 (충돌 방지)
  const tmpMap = [];
  for (let i = 0; i < files.length; i++) {
    const src = files[i].path;
    const ext = path.extname(files[i].name).toLowerCase();
    const tmp = path.join(folderPath, `__tmp_rename_${i}_${Date.now()}${ext}`);
    try {
      fs.renameSync(src, tmp);
      tmpMap.push({ tmp, ext, idx: i });
    } catch (e) {
      errors.push(`${files[i].name}: ${e.message}`);
    }
  }

  // 2단계: 최종 이름으로 이동
  const renamed = [];
  for (const { tmp, ext, idx } of tmpMap) {
    const newName = `${prefix}_${pad(idx)}${ext}`;
    const dest = path.join(folderPath, newName);
    try {
      fs.renameSync(tmp, dest);
      renamed.push({ oldPath: tmp, newPath: dest, newName });
    } catch (e) {
      errors.push(`${newName}: ${e.message}`);
    }
  }

  return { renamed, errors };
});

ipcMain.handle('reveal-folder', async (_event, folderPath) => {
  shell.openPath(folderPath);
});