import * as fs from 'fs';
import * as  path from 'path';
import {Plugin} from 'vite';

// 读取指定目录并找到所有以 .map 结尾的文件
function findMapFiles(dir: string): Promise<string[]> {
    return new Promise((resolve, reject) => {
        fs.readdir(dir, (err, files) => {
            if (err) {
                return reject(err);
            }
            const mapFiles = files.filter(file => file.endsWith('.map')).map(file => path.join(dir, file));
            resolve(mapFiles);
        });
    });
}

// 创建文件夹的函数
function createDir(dirPath: string): Promise<string> {
    return new Promise((resolve, reject) => {
        fs.mkdir(dirPath, {recursive: true}, (err) => {
            if (err) {
                return reject(err);
            }
            resolve(dirPath);
        });
    });
}

// 移动文件的函数
function moveFile(source: string, destination: string): Promise<string> {
    return new Promise((resolve, reject) => {
        fs.rename(source, destination, (err) => {
            if (err) {
                return reject(err);
            }
            resolve(destination);
        });
    });
}

//
/** 自定义 Vite 插件
 * 移动 .map 文件
 * @param outputDir
 * @param mapDir
 */
export function moveMapFilesPlugin(
    outputDir: string,
    mapDir: string
): Plugin {
    const res: Plugin = {
        name: 'move-map-files',
        async writeBundle() {
            await createDir(mapDir);
            await Promise.all(
                (await findMapFiles(outputDir)).map(async (mapFile) => {
                    const newMapFile = mapFile.replace(outputDir, mapDir);
                    await moveFile(mapFile, newMapFile);
                })
            );
        }
    };
    return res;
}