/**
 * 段落格式
 * @file
 * @since 1.2.6.1
 */

/**
 * 段落对齐方式
 * @command justify
 * @method execCommand
 * @param { String } cmd 命令字符串
 * @param { String } align 对齐方式：left => 居左，right => 居右，center => 居中，justify => 两端对齐
 * @example
 * ```javascript
 * editor.execCommand( 'justify', 'center' );
 * ```
 */
/**
 * 如果选区所在位置是段落区域，返回当前段落对齐方式
 * @command justify
 * @method queryCommandValue
 * @param { String } cmd 命令字符串
 * @return { String } 返回段落对齐方式
 * @example
 * ```javascript
 * editor.queryCommandValue( 'justify' );
 * ```
 */

UE.plugins['justify']=function(){
    var me=this,
        block = domUtils.isBlockElm,
        defaultValue = {
            left:1,
            right:1,
            center:1,
            justify:1
        },
        doJustify = function (range, style) {
            var bookmark = range.createBookmark(),
                filterFn = function (node) {
                    return node.nodeType == 1 ? node.tagName.toLowerCase() != 'br' && !domUtils.isBookmarkNode(node) : !domUtils.isWhitespace(node);
                };

            range.enlarge(true);
            var bookmark2 = range.createBookmark(),
                current = domUtils.getNextDomNode(bookmark2.start, false, filterFn),
                tmpRange = range.cloneRange(),
                tmpNode;
            while (current && !(domUtils.getPosition(current, bookmark2.end) & domUtils.POSITION_FOLLOWING)) {
                if (current.nodeType == 3 || !block(current)) {
                    tmpRange.setStartBefore(current);
                    while (current && current !== bookmark2.end && !block(current)) {
                        tmpNode = current;
                        current = domUtils.getNextDomNode(current, false, null, function (node) {
                            return !block(node);
                        });
                    }
                    tmpRange.setEndAfter(tmpNode);
                    var common = tmpRange.getCommonAncestor();
                    if (!domUtils.isBody(common) && block(common)) {
                        domUtils.setStyles(common, utils.isString(style) ? {'text-align':style} : style);
                        current = common;
                    } else {
                        var p = range.document.createElement('p');
                        domUtils.setStyles(p, utils.isString(style) ? {'text-align':style} : style);
                        var frag = tmpRange.extractContents();
                        p.appendChild(frag);
                        tmpRange.insertNode(p);
                        current = p;
                    }
                    current = domUtils.getNextDomNode(current, false, filterFn);
                } else {
                    current = domUtils.getNextDomNode(current, true, filterFn);
                }
            }
            return range.moveToBookmark(bookmark2).moveToBookmark(bookmark);
        };

    UE.commands['justify'] = {
        execCommand:function (cmdName, align) {
            var range = this.selection.getRange(),
                txt;

            //闭合时单独处理
            if (range.collapsed) {
                txt = this.document.createTextNode('p');
                range.insertNode(txt);
            }
            doJustify(range, align);
            if (txt) {
                range.setStartBefore(txt).collapse(true);
                domUtils.remove(txt);
            }

            range.select();


            return true;
        },
        queryCommandValue:function () {
            var startNode = this.selection.getStart(),
                value = domUtils.getComputedStyle(startNode, 'text-align');
            return defaultValue[value] ? value : 'left';
        },
        queryCommandState:function () {
            var start = this.selection.getStart(),
                cell = start && domUtils.findParentByTagName(start, ["td", "th","caption"], true);

            return cell? -1:0;
        }

    };
};
