import typescript from '@rollup/plugin-typescript';
import terser from '@rollup/plugin-terser';
import { nodeResolve } from '@rollup/plugin-node-resolve';
import commonjs from '@rollup/plugin-commonjs';
import replace from '@rollup/plugin-replace';
import { copyFileSync, existsSync, mkdirSync } from 'fs';
import { dirname, resolve } from 'path';

const ROOT = process.cwd();
const DIST_DIR = resolve(ROOT, 'dist');
const BACKEND_DIR = resolve(ROOT, '../src/main/resources/static/sdk');

const ASSETS = [
  { src: resolve(ROOT, 'assets/launcher-logo.png'), name: 'launcher-logo.png' },
];

const BUNDLE_FILES = ['chatbot-sdk.js', 'chatbot-sdk.min.js'];

/** 将构建产物与静态资源复制到指定目录 */
function copyFiles(srcFiles, targetDir, label) {
  if (!existsSync(targetDir)) mkdirSync(targetDir, { recursive: true });
  for (const { src, name } of srcFiles) {
    if (!existsSync(src)) {
      console.warn(`[copy-assets] 未找到 ${src}，跳过`);
      continue;
    }
    copyFileSync(src, resolve(targetDir, name));
  }
  console.log(`[copy-assets] 已复制 ${label} 到 ${targetDir}`);
}

/** Rollup 插件：构建结束后同步产物与 logo 到后端静态资源目录 */
function copyAssets() {
  return {
    name: 'copy-assets',
    closeBundle() {
      // 1. 复制 logo 到 dist（便于独立分发）
      copyFiles(
        ASSETS.map(a => ({ src: a.src, name: a.name })),
        DIST_DIR,
        'logo 到 dist'
      );

      // 2. 复制 logo + JS 产物到后端 static/sdk/
      const backendAssets = [
        ...ASSETS.map(a => ({ src: a.src, name: a.name })),
        ...BUNDLE_FILES.map(name => ({ src: resolve(DIST_DIR, name), name })),
      ];
      copyFiles(backendAssets, BACKEND_DIR, 'SDK 产物与 logo 到后端 static/sdk');
    },
  };
}

export default {
  input: 'src/index.ts',
  output: [
    {
      file: 'dist/chatbot-sdk.js',
      format: 'iife',
      name: 'ChatbotSDK',
      sourcemap: false,
      inlineDynamicImports: true,
    },
    {
      file: 'dist/chatbot-sdk.min.js',
      format: 'iife',
      name: 'ChatbotSDK',
      sourcemap: false,
      inlineDynamicImports: true,
      plugins: [terser()],
    },
  ],
  plugins: [
    // mermaid 不打包（省约 1.2MB gzip），用本地 stub 替换，避免 markdown-content 模块顶层
    // Cherry.usePlugin 注册 mermaid 插件时因缺少 mermaid 抛异常导致 IIFE 加载失败
    {
      name: 'mermaid-stub',
      resolveId(source) {
        if (source === 'mermaid') return resolve(ROOT, 'src/mermaid-stub.ts');
        return null;
      },
    },
    replace({
      preventAssignment: true,
      'process.env.NODE_ENV': JSON.stringify('production'),
    }),
    nodeResolve({
      browser: true,
      preferBuiltins: false,
    }),
    commonjs(),
    typescript({
      tsconfig: './tsconfig.json',
      declaration: false,
      declarationDir: undefined,
      sourceMap: false,
    }),
    copyAssets(),
  ],
};