import type * as esbuild from 'esbuild';

import {escape_regexp} from '@fuzdev/fuz_util/regexp.js';

import {join} from 'node:path';

export interface EsbuildPluginSveltekitShimAliasOptions {

dir?: string;

alias?: Record<string, string>;

}

export const esbuild_plugin_sveltekit_shim_alias = ({

dir = process.cwd(),

alias,

}: EsbuildPluginSveltekitShimAliasOptions): esbuild.Plugin => ({

name: 'sveltekit_shim_alias',

setup: (build) => {

const aliases: Record<string, string> = {$lib: 'src/lib', ...alias};

// Create a Go-compatible regexp

const filter = new RegExp(`^(?:${Object.keys(aliases).map(escape_regexp).join('|')})`);

build.onResolve({filter}, async (args) => {

const {path, ...rest} = args;

// Find which alias prefix matches

const prefix = Object.keys(aliases).find((key) => path.startsWith(key));

if (!prefix) return null;

return build.resolve(join(dir, aliases[prefix] + path.substring(prefix.length)), rest);

});

},

});