'use strict';

const inject = require('@rollup/plugin-inject');
const modules = require('./modules.js');
const path = require('path');
const crypto = require('crypto');
const polyfills = require('./polyfills.js');

// Node import paths use POSIX separators
const { dirname, relative, join } = path.posix;
const PREFIX = `\0polyfill-node.`;
const PREFIX_LENGTH = PREFIX.length;
function index (opts = {}) {
    const mods = modules.getModules();
    const injectPlugin = inject({
        include: opts.include === undefined ? ['node_modules/**/*.js'] : opts.include,
        exclude: opts.exclude,
        sourceMap: opts.sourceMap,
        modules: {
            process: PREFIX + "process",
            Buffer: [PREFIX + "buffer", "Buffer"],
            global: PREFIX + 'global',
            __filename: FILENAME_PATH,
            __dirname: DIRNAME_PATH,
        },
    });
    const basedir = opts.baseDir || "/";
    const dirs = new Map();
    return {
        name: "polyfill-node",
        resolveId(importee, importer) {
            // Fixes commonjs compatability: https://github.com/FredKSchott/rollup-plugin-polyfill-node/pull/42
            if (importee[0] == '\0' && /\?commonjs-\w+$/.test(importee)) {
                importee = importee.slice(1).replace(/\?commonjs-\w+$/, '');
            }
            if (importee === DIRNAME_PATH) {
                const id = getRandomId();
                dirs.set(id, dirname("/" + relative(basedir, importer)));
                return { id, moduleSideEffects: false };
            }
            if (importee === FILENAME_PATH) {
                const id = getRandomId();
                dirs.set(id, dirname("/" + relative(basedir, importer)));
                return { id, moduleSideEffects: false };
            }
            if (importee && importee.slice(-1) === "/") {
                importee = importee.slice(0, -1);
            }
            if (importer && importer.startsWith(PREFIX) && importee.startsWith('.')) {
                importee = PREFIX + join(importer.substr(PREFIX_LENGTH).replace('.js', ''), '..', importee) + '.js';
            }
            if (importee.startsWith(PREFIX)) {
                importee = importee.substr(PREFIX_LENGTH);
            }
            if (mods.has(importee) || polyfills[importee.replace('.js', '') + '.js']) {
                return { id: PREFIX + importee.replace('.js', '') + '.js', moduleSideEffects: false };
            }
            return null;
        },
        load(id) {
            if (dirs.has(id)) {
                return `export default '${dirs.get(id)}'`;
            }
            if (id.startsWith(PREFIX)) {
                const importee = id.substr(PREFIX_LENGTH).replace('.js', '');
                return mods.get(importee) || polyfills[importee + '.js'];
            }
        },
        transform(code, id) {
            if (id === PREFIX + 'global.js')
                return;
            // @ts-ignore
            return injectPlugin.transform.call(this, code, id.replace(PREFIX, path.resolve('node_modules', 'polyfill-node')));
        },
    };
}
function getRandomId() {
    return crypto.randomBytes(15).toString("hex");
}
const DIRNAME_PATH = "\0node-polyfills:dirname";
const FILENAME_PATH = "\0node-polyfills:filename";

module.exports = index;