import './at-rule'; // break cyclical dependency deadlock – #87

import Container from './container';
import warnOnce  from './warn-once';
import list      from './list';

/**
 * Represents a CSS rule: a selector followed by a declaration block.
 *
 * @extends Container
 *
 * @example
 * const root = postcss.parse('a{}');
 * const rule = root.first;
 * rule.type       //=> 'rule'
 * rule.toString() //=> 'a{}'
 */
class Rule extends Container {

    constructor(defaults) {
        super(defaults);
        this.type = 'rule';
        if ( !this.nodes ) this.nodes = [];
    }

    /**
     * An array containing the rule’s individual selectors.
     * Groups of selectors are split at commas.
     *
     * @type {string[]}
     *
     * @example
     * const root = postcss.parse('a, b { }');
     * const rule = root.first;
     *
     * rule.selector  //=> 'a, b'
     * rule.selectors //=> ['a', 'b']
     *
     * rule.selectors = ['a', 'strong'];
     * rule.selector //=> 'a, strong'
     */
    get selectors() {
        return list.comma(this.selector);
    }

    set selectors(values) {
        let match = this.selector ? this.selector.match(/,\s*/) : null;
        let sep   = match ? match[0] : ',' + this.raw('between', 'beforeOpen');
        this.selector = values.join(sep);
    }

    get _selector() {
        warnOnce('Rule#_selector is deprecated. Use Rule#raws.selector');
        return this.raws.selector;
    }

    set _selector(val) {
        warnOnce('Rule#_selector is deprecated. Use Rule#raws.selector');
        this.raws.selector = val;
    }

    /**
     * @memberof Rule#
     * @member {string} selector - the rule’s full selector represented
     *                             as a string
     *
     * @example
     * const root = postcss.parse('a, b { }');
     * const rule = root.first;
     * rule.selector //=> 'a, b'
     */

    /**
     * @memberof Rule#
     * @member {object} raws - Information to generate byte-to-byte equal
     *                         node string as it was in the origin input.
     *
     * Every parser saves its own properties,
     * but the default CSS parser uses:
     *
     * * `before`: the space symbols before the node. It also stores `*`
     *   and `_` symbols before the declaration (IE hack).
     * * `after`: the space symbols after the last child of the node
     *   to the end of the node.
     * * `between`: the symbols between the property and value
     *   for declarations, selector and `{` for rules, or last parameter
     *   and `{` for at-rules.
     * * `semicolon`: contains true if the last child has
     *   an (optional) semicolon.
     *
     * PostCSS cleans selectors from comments and extra spaces,
     * but it stores origin content in raws properties.
     * As such, if you don’t change a declaration’s value,
     * PostCSS will use the raw value with comments.
     *
     * @example
     * const root = postcss.parse('a {\n  color:black\n}')
     * root.first.first.raws //=> { before: '', between: ' ', after: '\n' }
     */

}

export default Rule;