"use strict";

const postcss = require("postcss");
const defaultValue = require("default-value");
const postcssValues = require("postcss-modules-values");
const postcssLocalByDefault = require("postcss-modules-local-by-default");
const postcssExtractImports = require("postcss-modules-extract-imports");
const postcssScope = require("postcss-modules-scope");
const genericNames = require("generic-names");

const postcssFindImports = require("./postcss-icss-find-imports");

module.exports = function createFilePreprocessor(options) {
	let generateScopedName = defaultValue(options.generateScopedName, genericNames("[name]__[local]---[hash:base64:5]"));

	let postcssInstance = postcss([
		... defaultValue(options.before, []),
		postcssValues,
		postcssLocalByDefault({ mode: defaultValue(options.mode, "local") }),
		postcssExtractImports(),
		postcssScope({
			generateScopedName: generateScopedName
		}),
		postcssFindImports()
	]);

	return function preprocessFile(item) {
		return postcssInstance.process(item.source, {
			from: item.file,
			... options
		});
	};
};