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

const pluginName = 'postcss-icss-parser';

module.exports = function(options = {}) {
	validateOptions(arguments, {
		keyReplacer: [ required, isFunction ],
		autoExportImports: [ isBoolean ]
	});

	return {
		postcssPlugin: pluginName,
		Once(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 },
					});
					
					if (options.autoExportImports !== false) {
						result.messages.push({
							pluginName: pluginName,
							type: "icss-export",
							item: {
								name: localKey,
								value: newKey
							}
						});
					}
				}
			}

			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 }
				});
			}
		},
	};
};

module.exports.postcss = true;