/*
 * Ext JS Library 2.0 Copyright(c) 2006-2007, Ext JS, LLC. licensing@extjs.com
 * 
 * http://extjs.com/license
 */

/**
 * @class Ext.layout.ContainerLayout Every layout is composed of one or more
 *        {@link Ext.Container} elements internally, and ContainerLayout
 *        provides the basic foundation for all other layout classes in Ext. It
 *        is a non-visual class that simply provides the base logic required for
 *        a Container to function as a layout. This class is intended to be
 *        extended and should generally not need to be created directly via the
 *        new keyword.
 */
Ext.layout.ContainerLayout = function(config) {
	Ext.apply(this, config);
};

Ext.layout.ContainerLayout.prototype = {
	/**
	 * @cfg {String} extraCls An optional extra CSS class that will be added to
	 *      the container (defaults to ''). This can be useful for adding
	 *      customized styles to the container or any of its children using
	 *      standard CSS rules.
	 */
	/**
	 * @cfg {Boolean} renderHidden True to hide each contained item on render
	 *      (defaults to false).
	 */

	/**
	 * A reference to the {@link Ext.Component} that is active. For example,
	 * if(myPanel.layout.activeItem.id == 'item-1') { ... }. activeItem only
	 * applies to layout styles that can display items one at a time (like
	 * {@link Ext.layout.Accordion}, {@link Ext.layout.CardLayout} and
	 * {@link Ext.layout.FitLayout}). Read-only. Related to
	 * {@link Ext.Container#activeItem}.
	 * 
	 * @type {Ext.Component}
	 * @property activeItem
	 */

	// private
	monitorResize : false,
	// private
	activeItem : null,

	// private
	layout : function() {
		var target = this.container.getLayoutTarget();
		this.onLayout(this.container, target);
		this.container.fireEvent('afterlayout', this.container, this);
	},

	// private
	onLayout : function(ct, target) {
		this.renderAll(ct, target);
	},

	// private
	isValidParent : function(c, target) {
		var el = c.getPositionEl ? c.getPositionEl() : c.getEl();
		return el.dom.parentNode == target.dom;
	},

	// private
	renderAll : function(ct, target) {
		var items = ct.items.items;
		for (var i = 0, len = items.length; i < len; i++) {
			var c = items[i];
			if (c && (!c.rendered || !this.isValidParent(c, target))) {
				this.renderItem(c, i, target);
			}
		}
	},

	// private
	renderItem : function(c, position, target) {
		if (c && !c.rendered) {
			if (this.extraCls) {
				c.addClass(this.extraCls);
			}
			c.render(target, position);
			if (this.renderHidden && c != this.activeItem) {
				c.hide();
			}
		} else if (c && !this.isValidParent(c, target)) {
			if (this.extraCls) {
				c.addClass(this.extraCls);
			}
			if (typeof position == 'number') {
				position = target.dom.childNodes[position];
			}
			target.dom.insertBefore(c.getEl().dom, position || null);
			if (this.renderHidden && c != this.activeItem) {
				c.hide();
			}
		}
	},

	// private
	onResize : function() {
		if (this.container.collapsed) {
			return;
		}
		var b = this.container.bufferResize;
		if (b) {
			if (!this.resizeTask) {
				this.resizeTask = new Ext.util.DelayedTask(this.layout, this);
				this.resizeBuffer = typeof b == 'number' ? b : 100;
			}
			this.resizeTask.delay(this.resizeBuffer);
		} else {
			this.layout();
		}
	},

	// private
	setContainer : function(ct) {
		if (this.monitorResize && ct != this.container) {
			if (this.container) {
				this.container.un('resize', this.onResize, this);
			}
			if (ct) {
				ct.on('resize', this.onResize, this);
			}
		}
		this.container = ct;
	},

	// private
	parseMargins : function(v) {
		var ms = v.split(' ');
		var len = ms.length;
		if (len == 1) {
			ms[1] = ms[0];
			ms[2] = ms[0];
			ms[3] = ms[0];
		}
		if (len == 2) {
			ms[2] = ms[0];
			ms[3] = ms[1];
		}
		return {
			top : parseInt(ms[0], 10) || 0,
			right : parseInt(ms[1], 10) || 0,
			bottom : parseInt(ms[2], 10) || 0,
			left : parseInt(ms[3], 10) || 0
		};
	}
};
Ext.Container.LAYOUTS['auto'] = Ext.layout.ContainerLayout;