var Node = require(“./node”),

Selector = require("./selector");

var Extend = function Extend(selector, option, index, currentFileInfo, visibilityInfo) {

this.selector = selector;
this.option = option;
this.index = index;
this.object_id = Extend.next_id++;
this.parent_ids = [this.object_id];
this.currentFileInfo = currentFileInfo || {};
this.copyVisibilityInfo(visibilityInfo);

switch(option) {
    case "all":
        this.allowBefore = true;
        this.allowAfter = true;
        break;
    default:
        this.allowBefore = false;
        this.allowAfter = false;
        break;
}

}; Extend.next_id = 0;

Extend.prototype = new Node(); Extend.prototype.type = “Extend”; Extend.prototype.accept = function (visitor) {

this.selector = visitor.visit(this.selector);

}; Extend.prototype.eval = function (context) {

return new Extend(this.selector.eval(context), this.option, this.index, this.currentFileInfo, this.visibilityInfo());

}; Extend.prototype.clone = function (context) {

return new Extend(this.selector, this.option, this.index, this.currentFileInfo, this.visibilityInfo());

}; //it concatenates (joins) all selectors in selector array Extend.prototype.findSelfSelectors = function (selectors) {

var selfElements = [],
    i,
    selectorElements;

for (i = 0; i < selectors.length; i++) {
    selectorElements = selectors[i].elements;
    // duplicate the logic in genCSS function inside the selector node.
    // future TODO - move both logics into the selector joiner visitor
    if (i > 0 && selectorElements.length && selectorElements[0].combinator.value === "") {
        selectorElements[0].combinator.value = ' ';
    }
    selfElements = selfElements.concat(selectors[i].elements);
}

this.selfSelectors = [new Selector(selfElements)];
this.selfSelectors[0].copyVisibilityInfo(this.visibilityInfo());

}; module.exports = Extend;