/**
 * Plugin for Freemind import.
 * See https://github.com/jiangxin/freemind-mmx/tree/master/freemind
 */
Draw.loadPlugin(function(ui) {
	var graph = ui.editor.graph;
	
	// Adds resource for action
	mxResources.parse('importFreemind=Freemind');
	
	// Parses Freemind data
	function importFreemindData(data)
	{
		// Gets the default parent for inserting new cells. This
		// is normally the first child of the root (ie. layer 0).
		var defaultParent = graph.getDefaultParent();
		var cells = [];
		
		var defaultWidth = 80;
		var defaultHeight = 30;
		var mainConceptHeight = 40;
		var defaultHorizontalSpaceBetweenVertex = 40; 
		var defaultVerticalSpaceBetweenVertex = 10;

		var freeMindMainConceptVertexStyle = "ellipse;whiteSpace=wrap;html=1;align=center;collapsible=0;container=1;recursiveResize=0;";
		var freeMindBranchVertexStyle = "whiteSpace=wrap;html=1;shape=partialRectangle;top=0;left=0;bottom=1;right=0;points=[[0,1],[1,1]];strokeColor=#000000;fillColor=none;align=center;verticalAlign=bottom;routingCenterY=0.5;snapToPoint=1;collapsible=0;container=1;recursiveResize=0;autosize=1;";
		var freeMindConceptVertexStyle = "whiteSpace=wrap;html=1;rounded=1;arcSize=50;align=center;verticalAlign=middle;collapsible=0;container=1;recursiveResize=0;strokeWidth=1;autosize=1;spacing=4;";
		var freeMindEdgeStyle = "edgeStyle=entityRelationEdgeStyle;startArrow=none;endArrow=none;segment=10;curved=1;html=1;";
		
		// Tells whether or not a node has child ideas
		var hasChilds = function(node){
			for (var i = 0; i < node.childNodes.length; i++){
				if (node.childNodes[i].nodeName == "node"){
					return true;
				}
			}
			return false;
		};
		
		// Generates useful info on the nodes to be used later.
		var generatePreprocessingNodeInfo = function(node){
			var childCount = 0;
			var maxChildsInHierarchy = 0;
			for (var i = 0; i < node.childNodes.length; i++){
				var childNode = node.childNodes[i];
				if (childNode.nodeName == "node"){
					var maxChilds = generatePreprocessingNodeInfo(childNode);
					maxChildsInHierarchy = Math.max(maxChildsInHierarchy, maxChilds);
					childCount++;
				}
			}
			node.childCount = childCount; 
			node.maxChilds = Math.max(childCount, maxChildsInHierarchy);
			return childCount;
		}
		
		// Main node generation funcion (recursive)
		var processFreeMindNode = function(node, nodeParent, x, y){
			var mainConcept = false;
			var vertexStyle = freeMindBranchVertexStyle;
			if (nodeParent == defaultParent){
				mainConcept = true;
				vertexStyle = freeMindMainConceptVertexStyle;
			}else if (hasChilds(node)){
				// Concept, style appropiately
				vertexStyle = freeMindConceptVertexStyle;
			}
			var nodeName = node.getAttribute('TEXT') || "";
			var nodeVertex = graph.insertVertex(defaultParent, null, nodeName, x, y, defaultWidth, defaultHeight, vertexStyle);
			graph.cellLabelChanged(nodeVertex,nodeName,true);
			if (mainConcept){
				nodeVertex.geometry.height = mainConceptHeight; // TODO: Maybe set height according to it's width, so it's rounded?
			}
			if (nodeParent != defaultParent){
				// Don't generate an edge for the first node
				graph.insertEdge(defaultParent, null, '', nodeParent, nodeVertex, freeMindEdgeStyle);		
			}
			cells.push(nodeVertex);			
			// Insert child nodes, on correct positions
			var childNumber = 0;
			for (var i = 0; i < node.childNodes.length; i++){
				var childNode = node.childNodes[i];
				if (childNode.nodeName == "node"){
					var childX = x + nodeVertex.geometry.width + defaultHorizontalSpaceBetweenVertex;
					var childY = y + (defaultHeight + defaultVerticalSpaceBetweenVertex) * childNumber;
					childNumber += childNode.maxChilds == 0? 1 : childNode.maxChilds;
					processFreeMindNode(childNode, nodeVertex, childX, childY);
				}
			}
		}
		
		// Makes the import one undoable edit
		graph.getModel().beginUpdate();
		try
		{
			// Gets point for free space in the graph for insert
			var pt = graph.getFreeInsertPoint();
			
			var freeMindParser = new DOMParser();
			freeMindDOM = freeMindParser.parseFromString(data, "text/xml");
			
			var freeMindDOMchilds = freeMindDOM.children[0];
			
			// Transverse the childs, and generate relevant input 
			for (var i = 0; i < freeMindDOMchilds.childNodes.length; i++){
				if (freeMindDOMchilds.childNodes[i].nodeName == "node"){
					generatePreprocessingNodeInfo(freeMindDOMchilds.childNodes[i]);
				}
			}
			// Generate the nodes
			for (var i = 0; i < freeMindDOMchilds.childNodes.length; i++){
				if (freeMindDOMchilds.childNodes[i].nodeName == "node"){
					processFreeMindNode(freeMindDOMchilds.childNodes[i], defaultParent, pt.x, pt.y);
				}
			}
			
			// Applies current styles to new cells (might not be needed)
			graph.fireEvent(new mxEventObject('cellsInserted', 'cells', cells));
		}
		finally
		{
			graph.getModel().endUpdate();
		}
		
		// Selects new cells and scrolls into view
		graph.setSelectionCells(cells);
       	graph.scrollCellToVisible(graph.getSelectionCell());
	};

  	// Adds action
	ui.actions.addAction('importFreemind...', function()
	{
		// Only modern browsers for now. We'll move the import
		// code above to the main codebase later
		if (Graph.fileSupport && !mxClient.IS_IE && !mxClient.IS_IE11)
		{
			var input = document.createElement('input');
			input.setAttribute('type', 'file');
			
			mxEvent.addListener(input, 'change', function()
			{
				if (input.files != null)
				{
					// Only one file for now...
					var reader = new FileReader();
					
					reader.onload = function(e)
					{
						importFreemindData(e.target.result);
					};
					
					reader.readAsText(input.files[0]);
				}
			});

			input.click();
		}
	});
	
	// Adds menu
	ui.menubar.addMenu('Import', function(menu, parent)
	{
		ui.menus.addMenuItem(menu, 'importFreemind');
	});
	
	// Moves import menu to before help menu
	ui.menubar.container.insertBefore(ui.menubar.container.lastChild,
		ui.menubar.container.lastChild.previousSibling.previousSibling.previousSibling);
});