"use strict";

/*
This module is derived from: css-loader (https://github.com/webpack-contrib/css-loader)
	(c) JS Foundation and other contributors

Modifications by:
	(c) 2019, Sven Slootweg <admin@cryto.net>

Licensed under:
	MIT (https://opensource.org/licenses/MIT)
*/

const postcss = require("postcss");
const icssUtils = require("icss-utils");
const loaderUtils = require("loader-utils");
const { validateOptions } = require("@validatem/core");
const required = require("@validatem/required");
const isFunction = require("@validatem/is-function");

const pluginName = 'postcss-icss-parser';

module.exports = postcss.plugin(pluginName, (options = {}) => {
	validateOptions([options], {
		keyReplacer: [ required, isFunction ]
	});

	return function process(css, result) {
		const importReplacements = Object.create(null);
		const { icssImports, icssExports } = icssUtils.extractICSS(css);

		let index = 0;

		for (const [ importUrl, imports ] of Object.entries(icssImports)) {
			const url = loaderUtils.parseString(importUrl);
			
			for (const [ localKey, remoteKey ] of Object.entries(imports)) {
				index += 1;
				
				let newKey = options.keyReplacer({ localKey, remoteKey, index, url });
				importReplacements[localKey] = newKey;

				result.messages.push({
					pluginName,
					type: 'icss-import',
					item: { url, localKey, remoteKey, newKey, index },
				});
			}
		}

		icssUtils.replaceSymbols(css, importReplacements);

		for (const [ name, value ] of Object.entries(icssExports)) {
			/* This is to handle re-exports of imported items */
			const parsedValue = icssUtils.replaceValueSymbols(
				value,
				importReplacements
			);

			result.messages.push({
				pluginName: pluginName,
				type: "icss-export",
				item: { name, value: parsedValue }
			});
		}
	};
});