import type { Alias, AliasOptions, Plugin } from 'vite';
import process from 'node:process';
import { pathToFileURL } from 'node:url';
import { getPackages } from '@manypkg/get-packages';
import packageJson from '../package.json';

async function collectEntryAlias(packageDirSet: Set<string>): Promise<Alias[]> {
  const workspaces = await getPackages(process.cwd());
  return Object.entries(packageJson.dependencies).reduce((cur: any, pkg) => {
    const [name, version] = pkg;

    if (name && (version as any).startsWith('workspace')) {
      const packageObj = workspaces.packages.find(p => p.packageJson.name === name);
      if (packageObj) {
        cur.push({
          find: new RegExp(`^${name}$`),
          // replacement: path.resolve(packageObj.dir, './src/index'),
          replacement: new URL('./src/index', pathToFileURL(`${packageObj.dir}/`)),
        });
        packageDirSet.add(packageObj.dir);
      }
    }
    return cur;
  }, []);
}
function mergeAlias(alias: AliasOptions, aliases: Alias[]) {
  if (Array.isArray(alias)) {
    return [...aliases, ...alias];
  } else {
    return Object.entries(alias).reduce((cur, [key, value]) => {
      cur.push({
        find: key,
        replacement: value,
      });
      return cur;
    }, aliases);
  }
}
export async function Aliases(): Promise<Plugin> {
  const packageDirSet = new Set<string>();
  const aliases = await collectEntryAlias(packageDirSet);
  return {
    name: 'aliases',
    enforce: 'pre',
    config(config) {
      config.resolve = {
        ...config.resolve,
        alias: config.resolve?.alias ? mergeAlias(config.resolve.alias, aliases) : aliases,
      };
    },
    transform(code, id) {
      // 取根目录路径
      const dir = id.split('/src/')[0];
      // 将引用地方的 `@` 别名替换为子包的绝对路径
      code = code.replace(/from '@\//g, `from '${dir}/src/`)
        .replace(/import\('@\//g, `import('${dir}/src/`);
      return {
        code,
        map: null,
      };
    },
  };
}