dojo.provide("dijit.layout.StackContainer");

dojo.require("dijit._Templated");
dojo.require("dijit.layout._LayoutWidget");
dojo.require("dijit.form.Button");
dojo.require("dijit.Menu");
dojo.requireLocalization("dijit", "common");

dojo.declare(
	"dijit.layout.StackContainer",
	dijit.layout._LayoutWidget,
	{
	// summary: 
	//	A container that has multiple children, but shows only
	//	one child at a time
	//
	// description:
	// 	A container for widgets (ContentPanes, for example) That displays
	//	only one Widget at a time.
	//	
	//	Publishes topics [widgetId]-addChild, [widgetId]-removeChild, and [widgetId]-selectChild
	//
	//	Can be base class for container, Wizard, Show, etc.

	// doLayout: Boolean
	//  if true, change the size of my currently displayed child to match my size
	doLayout: true,

	baseClass: "dijitStackContainer",

	_started: false,
/*=====
	// selectedChildWidget: Widget
	//	References the currently selected child widget, if any
	//
	selectedChildWidget: null,
=====*/
	postCreate: function(){
		this.inherited(arguments);
		dijit.setWaiRole(this.containerNode, "tabpanel");
		this.connect(this.domNode, "onkeypress", this._onKeyPress);
	},
	
	startup: function(){
		if(this._started){ return; }

		var children = this.getChildren();

		// Setup each page panel
		dojo.forEach(children, this._setupChild, this);

		// Figure out which child to initially display
		dojo.some(children, function(child){
			if(child.selected){
				this.selectedChildWidget = child;
			}
			return child.selected;
		}, this);

		var selected = this.selectedChildWidget;

		// Default to the first child
		if(!selected && children[0]){
			selected = this.selectedChildWidget = children[0];
			selected.selected = true;
		}
		if(selected){
			this._showChild(selected);
		}

		// Now publish information about myself so any StackControllers can initialize..
		dojo.publish(this.id+"-startup", [{children: children, selected: selected}]);

		this.inherited(arguments);
	},

	_setupChild: function(/*Widget*/ child){
		// Summary: prepare the given child

		this.inherited(arguments);

		child.domNode.style.display = "none";

		// since we are setting the width/height of the child elements, they need
		// to be position:relative, or IE has problems (See bug #2033)
		child.domNode.style.position = "relative";

		// remove the title attribute so it doesn't show up when i hover
		// over a node
		child.domNode.title = "";

		return child; // dijit._Widget
	},

	addChild: function(/*Widget*/ child, /*Integer?*/ insertIndex){
		// summary: Adds a widget to the stack
		 
		this.inherited(arguments);

		if(this._started){
			dojo.publish(this.id+"-addChild", [child, insertIndex]);

			// in case the tab titles have overflowed from one line to two lines
			// (or, if this if first child, from zero lines to one line)
			this.layout();

			// if this is the first child, then select it
			if(!this.selectedChildWidget){
				this.selectChild(child);
			}
		}
	},

	removeChild: function(/*Widget*/ page){
		// summary: Removes the pane from the stack

		this.inherited(arguments);

		// If we are being destroyed than don't run the code below (to select another page), because we are deleting
		// every page one by one
		if(this._beingDestroyed){ return; }

		if(this._started){
			// this will notify any tablists to remove a button; do this first because it may affect sizing
			dojo.publish(this.id+"-removeChild", [page]);

			// in case the tab titles now take up one line instead of two lines
			this.layout();
		}

		if(this.selectedChildWidget === page){
			this.selectedChildWidget = undefined;
			if(this._started){
				var children = this.getChildren();
				if(children.length){
					this.selectChild(children[0]);
				}
			}
		}
	},

	selectChild: function(/*Widget*/ page){
		// summary:
		//	Show the given widget (which must be one of my children)

		page = dijit.byId(page);

		if(this.selectedChildWidget != page){
			// Deselect old page and select new one
			this._transition(page, this.selectedChildWidget);
			this.selectedChildWidget = page;
			dojo.publish(this.id+"-selectChild", [page]);
		}
	},

	_transition: function(/*Widget*/newWidget, /*Widget*/oldWidget){
		if(oldWidget){
			this._hideChild(oldWidget);
		}
		this._showChild(newWidget);

		// Size the new widget, in case this is the first time it's being shown,
		// or I have been resized since the last time it was shown.
		// page must be visible for resizing to work
		if(this.doLayout && newWidget.resize){
			newWidget.resize(this._containerContentBox || this._contentBox);
		}
	},

	_adjacent: function(/*Boolean*/ forward){
		// summary: Gets the next/previous child widget in this container from the current selection
		var children = this.getChildren();
		var index = dojo.indexOf(children, this.selectedChildWidget);
		index += forward ? 1 : children.length - 1;
		return children[ index % children.length ]; // dijit._Widget
	},

	forward: function(){
		// Summary: advance to next page
		this.selectChild(this._adjacent(true));
	},

	back: function(){
		// Summary: go back to previous page
		this.selectChild(this._adjacent(false));
	},

	_onKeyPress: function(e){
		dojo.publish(this.id+"-containerKeyPress", [{ e: e, page: this}]);
	},

	layout: function(){
		if(this.doLayout && this.selectedChildWidget && this.selectedChildWidget.resize){
			this.selectedChildWidget.resize(this._contentBox);
		}
	},

	_showChild: function(/*Widget*/ page){
		var children = this.getChildren();
		page.isFirstChild = (page == children[0]);
		page.isLastChild = (page == children[children.length-1]);
		page.selected = true;

		page.domNode.style.display="";
		if(page._loadCheck){
			page._loadCheck(); // trigger load in ContentPane
		}
		if(page.onShow){
			page.onShow();
		}
	},

	_hideChild: function(/*Widget*/ page){
		page.selected=false;
		page.domNode.style.display="none";
		if(page.onHide){
			page.onHide();
		}
	},

	closeChild: function(/*Widget*/ page){
		// summary:
		//	callback when user clicks the [X] to remove a page
		//	if onClose() returns true then remove and destroy the child
		var remove = page.onClose(this, page);
		if(remove){
			this.removeChild(page);
			// makes sure we can clean up executeScripts in ContentPane onUnLoad
			page.destroyRecursive();
		}
	},

	destroy: function(){
		this._beingDestroyed = true;
		this.inherited(arguments);
	}
});

dojo.declare(
	"dijit.layout.StackController",
	[dijit._Widget, dijit._Templated, dijit._Container],
	{
	// summary:
	//	Set of buttons to select a page in a page list.
	//	Monitors the specified StackContainer, and whenever a page is
	//	added, deleted, or selected, updates itself accordingly.

		templateString: "<span wairole='tablist' dojoAttachEvent='onkeypress' class='dijitStackController'></span>",

		// containerId: String
		//	the id of the page container that I point to
		containerId: "",

		// buttonWidget: String
		//	the name of the button widget to create to correspond to each page
		buttonWidget: "dijit.layout._StackButton",

		postCreate: function(){
			dijit.setWaiRole(this.domNode, "tablist");

			// TODO: change key from object to id, to get more separation from StackContainer
			this.pane2button = {};		// mapping from panes to buttons
			this.pane2handles = {};		// mapping from panes to dojo.connect() handles
			this.pane2menu = {};		// mapping from panes to close menu

			this._subscriptions=[
				dojo.subscribe(this.containerId+"-startup", this, "onStartup"),
				dojo.subscribe(this.containerId+"-addChild", this, "onAddChild"),
				dojo.subscribe(this.containerId+"-removeChild", this, "onRemoveChild"),
				dojo.subscribe(this.containerId+"-selectChild", this, "onSelectChild"),
				dojo.subscribe(this.containerId+"-containerKeyPress", this, "onContainerKeyPress")
			];
		},

		onStartup: function(/*Object*/ info){
			// summary: called after StackContainer has finished initializing
			dojo.forEach(info.children, this.onAddChild, this);
			this.onSelectChild(info.selected);
		},

		destroy: function(){
			for(var pane in this.pane2button){
				this.onRemoveChild(pane);
			}
			dojo.forEach(this._subscriptions, dojo.unsubscribe);
			this.inherited(arguments);
		},

		onAddChild: function(/*Widget*/ page, /*Integer?*/ insertIndex){
			// summary:
			//   Called whenever a page is added to the container.
			//   Create button corresponding to the page.

			// add a node that will be promoted to the button widget
			var refNode = dojo.doc.createElement("span");
			this.domNode.appendChild(refNode);
			// create an instance of the button widget
			var cls = dojo.getObject(this.buttonWidget);
			var button = new cls({label: page.title, closeButton: page.closable}, refNode);
			this.addChild(button, insertIndex);
			this.pane2button[page] = button;
			page.controlButton = button;	// this value might be overwritten if two tabs point to same container

			var handles = [];
			handles.push(dojo.connect(button, "onClick", dojo.hitch(this,"onButtonClick",page)));
			if(page.closable){
				handles.push(dojo.connect(button, "onClickCloseButton", dojo.hitch(this,"onCloseButtonClick",page)));
				// add context menu onto title button
				var _nlsResources = dojo.i18n.getLocalization("dijit", "common");
				var closeMenu = new dijit.Menu({targetNodeIds:[button.id], id:button.id+"_Menu"});
				var mItem = new dijit.MenuItem({label:_nlsResources.itemClose});
				handles.push(dojo.connect(mItem, "onClick", dojo.hitch(this, "onCloseButtonClick", page)));
				closeMenu.addChild(mItem);
				this.pane2menu[page] = closeMenu;
			}
			this.pane2handles[page] = handles;
			if(!this._currentChild){ // put the first child into the tab order
				button.focusNode.setAttribute("tabIndex", "0");
				this._currentChild = page;
			}
			//make sure all tabs have the same length
			if(!this.isLeftToRight() && dojo.isIE && this._rectifyRtlTabList){
				this._rectifyRtlTabList();
			}
		},

		onRemoveChild: function(/*Widget*/ page){
			// summary:
			//   Called whenever a page is removed from the container.
			//   Remove the button corresponding to the page.
			if(this._currentChild === page){ this._currentChild = null; }
			dojo.forEach(this.pane2handles[page], dojo.disconnect);
			delete this.pane2handles[page];
			var menu = this.pane2menu[page];
			if (menu){
				menu.destroyRecursive();
				delete this.pane2menu[page];
			}
			var button = this.pane2button[page];
			if(button){
				// TODO? if current child { reassign }
				button.destroy();
				delete this.pane2button[page];
			}
		},

		onSelectChild: function(/*Widget*/ page){
			// summary:
			//	Called when a page has been selected in the StackContainer, either by me or by another StackController

			if(!page){ return; }

			if(this._currentChild){
				var oldButton=this.pane2button[this._currentChild];
				oldButton.attr('checked', false);
				oldButton.focusNode.setAttribute("tabIndex", "-1");
			}

			var newButton=this.pane2button[page];
			newButton.attr('checked', true);
			this._currentChild = page;
			newButton.focusNode.setAttribute("tabIndex", "0");
			var container = dijit.byId(this.containerId);
			dijit.setWaiState(container.containerNode, "labelledby", newButton.id);
		},

		onButtonClick: function(/*Widget*/ page){
			// summary:
			//   Called whenever one of my child buttons is pressed in an attempt to select a page
			var container = dijit.byId(this.containerId);	// TODO: do this via topics?
			container.selectChild(page); 
		},

		onCloseButtonClick: function(/*Widget*/ page){
			// summary:
			//   Called whenever one of my child buttons [X] is pressed in an attempt to close a page
			var container = dijit.byId(this.containerId);
			container.closeChild(page);
			var b = this.pane2button[this._currentChild];
			if(b){
				dijit.focus(b.focusNode || b.domNode);
			}
		},
		
		// TODO: this is a bit redundant with forward, back api in StackContainer
		adjacent: function(/*Boolean*/ forward){
			if(!this.isLeftToRight() && (!this.tabPosition || /top|bottom/.test(this.tabPosition))){ forward = !forward; }
			// find currently focused button in children array
			var children = this.getChildren();
			var current = dojo.indexOf(children, this.pane2button[this._currentChild]);
			// pick next button to focus on
			var offset = forward ? 1 : children.length - 1;
			return children[ (current + offset) % children.length ]; // dijit._Widget
		},

		onkeypress: function(/*Event*/ e){
			// summary:
			//   Handle keystrokes on the page list, for advancing to next/previous button
			//   and closing the current page if the page is closable.

			if(this.disabled || e.altKey ){ return; }
			var forward = null;
			if(e.ctrlKey || !e._djpage){
				var k = dojo.keys;
				switch(e.charOrCode){
					case k.LEFT_ARROW:
					case k.UP_ARROW:
						if(!e._djpage){ forward = false; }
						break;
					case k.PAGE_UP:
						if(e.ctrlKey){ forward = false; }
						break;
					case k.RIGHT_ARROW:
					case k.DOWN_ARROW:
						if(!e._djpage){ forward = true; }
						break;
					case k.PAGE_DOWN:
						if(e.ctrlKey){ forward = true; }
						break;
					case k.DELETE:
						if(this._currentChild.closable){
							this.onCloseButtonClick(this._currentChild);
						}
						dojo.stopEvent(e);
						break;
					default:
						if(e.ctrlKey){
							if(e.charOrCode === k.TAB){
								this.adjacent(!e.shiftKey).onClick();
								dojo.stopEvent(e);
							}else if(e.charOrCode == "w"){
								if(this._currentChild.closable){
									this.onCloseButtonClick(this._currentChild);
								}
								dojo.stopEvent(e); // avoid browser tab closing.
							}
						}
				}
				// handle page navigation
				if(forward !== null){
					this.adjacent(forward).onClick();
					dojo.stopEvent(e);
				}
			}
		},

		onContainerKeyPress: function(/*Object*/ info){
			info.e._djpage = info.page;
			this.onkeypress(info.e);
		}
});

dojo.declare("dijit.layout._StackButton",
	dijit.form.ToggleButton,
	{
	// summary
	//	Internal widget used by StackContainer.
	//	The button-like or tab-like object you click to select or delete a page
	
	tabIndex: "-1", // StackContainer buttons are not in the tab order by default
	
	postCreate: function(/*Event*/ evt){
		dijit.setWaiRole((this.focusNode || this.domNode), "tab");
		this.inherited(arguments);
	},
	
	onClick: function(/*Event*/ evt){
		// summary: This is for TabContainer where the tabs are <span> rather than button,
		// 	so need to set focus explicitly (on some browsers)
		dijit.focus(this.focusNode);

		// ... now let StackController catch the event and tell me what to do
	},

	onClickCloseButton: function(/*Event*/ evt){
		// summary
		//	StackContainer connects to this function; if your widget contains a close button
		//	then clicking it should call this function.
		evt.stopPropagation();
	}
});

// These arguments can be specified for the children of a StackContainer.
// Since any widget can be specified as a StackContainer child, mix them
// into the base widget class.  (This is a hack, but it's effective.)
dojo.extend(dijit._Widget, {
	// title: String
	//		Title of this widget.  Used by TabContainer to the name the tab, etc.
	title: "",

	// selected: Boolean
	//		Is this child currently selected?
	selected: false,

	// closable: Boolean
	//		True if user can close (destroy) this child, such as (for example) clicking the X on the tab.
	closable: false,	// true if user can close this tab pane

	onClose: function(){
		// summary: Callback if someone tries to close the child, child will be closed if func returns true
		return true;
	}
});