const list = require('postcss').list;

module.exports = {

    /**
     * Throw special error, to tell beniary,
     * that this error is from Autoprefixer.
     */
    error(text) {
        const err = new Error(text);
        err.autoprefixer = true;
        throw err;
    },

    /**
     * Return array, that doesn’t contain duplicates.
     */
    uniq(array) {
        const filtered = [];
        for (const i of array) {
            if (filtered.indexOf(i) === -1) {
                filtered.push(i);
            }
        }
        return filtered;
    },

    /**
     * Return "-webkit-" on "-webkit- old"
     */
    removeNote(string) {
        if (string.indexOf(' ') === -1) {
            return string;
        }

        return string.split(' ')[0];
    },

    /**
     * Escape RegExp symbols
     */
    escapeRegexp(string) {
        return string.replace(/[.?*+\^\$\[\]\\(){}|\-]/g, '\\$&');
    },

    /**
     * Return regexp to check, that CSS string contain word
     */
    regexp(word, escape = true) {
        if (escape) {
            word = this.escapeRegexp(word);
        }
        return new RegExp(`(^|[\\s,(])(${word}($|[\\s(,]))`, 'gi');
    },

    /**
     * Change comma list
     */
    editList(value, callback) {
        const origin = list.comma(value);
        const changed = callback(origin, []);

        if (origin === changed) {
            return value;
        }

        let join = value.match(/,\s*/);
        join = join ? join[0] : ', ';
        return changed.join(join);
    }

};
