/*
Embedded SVG-edit API

General usage:
- Have an iframe somewhere pointing to a version of svg-edit > r1000
- Initialize the magic with:
var svgCanvas = new EmbeddedSVGEdit(window.frames.svgedit);
- Pass functions in this format:
svgCanvas.setSvgString('string')
- Or if a callback is needed:
svgCanvas.setSvgString('string')(function(data, error){
  if (error){
    // There was an error
  } else{
    // Handle data
  }
})

Everything is done with the same API as the real svg-edit,
and all documentation is unchanged.

However, this file depends on the postMessage API which
can only support JSON-serializable arguments and
return values, so, for example, arguments whose value is
'undefined', a function, a non-finite number, or a built-in
object like Date(), RegExp(), etc. will most likely not behave
as expected. In such a case one may need to host
the SVG editor on the same domain and reference the
JavaScript methods on the frame itself.

The only other difference is
when handling returns: the callback notation is used instead.

var blah = new EmbeddedSVGEdit(window.frames.svgedit);
blah.clearSelection('woot', 'blah', 1337, [1, 2, 3, 4, 5, 'moo'], -42, {a: 'tree',b:6, c: 9})(function(){console.log('GET DATA',arguments)})
*/

(function () {'use strict';

var cbid = 0;

function getCallbackSetter (d) {
  return function () {
    var t = this, // New callback
      args = [].slice.call(arguments),
      cbid = t.send(d, args, function(){});  // The callback (currently it's nothing, but will be set later)

    return function(newcallback){
      t.callbacks[cbid] = newcallback; // Set callback
    };
  };
}

/*
* Having this separate from messageListener allows us to
* avoid using JSON parsing (and its limitations) in the case
* of same domain control
*/
function addCallback (t, data) {
  var result = data.result || data.error,
	cbid = data.id;
  if (t.callbacks[cbid]) {
    if (data.result) {
      t.callbacks[cbid](result);
    } else {
      t.callbacks[cbid](result, 'error');
    }
  }
}

function messageListener (e) {
  // We accept and post strings as opposed to objects for the sake of IE9 support; this
  //   will most likely be changed in the future
  if (typeof e.data !== 'string') {
    return;
  }
  var allowedOrigins = this.allowedOrigins,
    data = e.data && JSON.parse(e.data);
  if (!data || typeof data !== 'object' || data.namespace !== 'svg-edit' ||
      e.source !== this.frame.contentWindow ||
      (allowedOrigins.indexOf('*') === -1 && allowedOrigins.indexOf(e.origin) === -1)
  ) {
    return;
  }
  addCallback(this, data);
}

function getMessageListener (t) {
	return function (e) {
		messageListener.call(t, e);
	};
}

/**
* @param {HTMLIFrameElement} frame
* @param {array} [allowedOrigins=[]] Array of origins from which incoming
*     messages will be allowed when same origin is not used; defaults to none.
*     If supplied, it should probably be the same as svgEditor's allowedOrigins
*/
function EmbeddedSVGEdit (frame, allowedOrigins) {
  if (!(this instanceof EmbeddedSVGEdit)) { // Allow invocation without 'new' keyword
    return new EmbeddedSVGEdit(frame);
  }
  this.allowedOrigins = allowedOrigins || [];
  // Initialize communication
  this.frame = frame;
  this.callbacks = {};
  // List of functions extracted with this:
  // Run in firebug on http://svg-edit.googlecode.com/svn/trunk/docs/files/svgcanvas-js.html

  // for (var i=0,q=[],f = document.querySelectorAll('div.CFunction h3.CTitle a'); i < f.length; i++) { q.push(f[i].name); }; q
  // var functions = ['clearSelection', 'addToSelection', 'removeFromSelection', 'open', 'save', 'getSvgString', 'setSvgString',
  // 'createLayer', 'deleteCurrentLayer', 'setCurrentLayer', 'renameCurrentLayer', 'setCurrentLayerPosition', 'setLayerVisibility',
  // 'moveSelectedToLayer', 'clear'];

  // Newer, well, it extracts things that aren't documented as well. All functions accessible through the normal thingy can now be accessed though the API
  // var svgCanvas = frame.contentWindow.svgCanvas;
  // var l = []; for (var i in svgCanvas){ if (typeof svgCanvas[i] == 'function') { l.push(i);} };
  // alert("['" + l.join("', '") + "']");
  // Run in svgedit itself
  var i,
	functions = [
		'clearSvgContentElement', 'setIdPrefix', 'getCurrentDrawing', 'addSvgElementFromJson', 'getTransformList', 'matrixMultiply', 'hasMatrixTransform', 'transformListToTransform', 'convertToNum', 'findDefs', 'getUrlFromAttr', 'getHref', 'setHref', 'getBBox', 'getRotationAngle', 'getElem', 'getRefElem', 'assignAttributes', 'cleanupElement', 'remapElement', 'recalculateDimensions', 'sanitizeSvg', 'runExtensions', 'addExtension', 'round', 'getIntersectionList', 'getStrokedBBox', 'getVisibleElements', 'getVisibleElementsAndBBoxes', 'groupSvgElem', 'getId', 'getNextId', 'call', 'bind', 'prepareSvg', 'setRotationAngle', 'recalculateAllSelectedDimensions', 'clearSelection', 'addToSelection', 'selectOnly', 'removeFromSelection', 'selectAllInCurrentLayer', 'getMouseTarget', 'removeUnusedDefElems', 'svgCanvasToString', 'svgToString', 'embedImage', 'setGoodImage', 'open', 'save', 'rasterExport', 'getSvgString', 'randomizeIds', 'uniquifyElems', 'setUseData', 'convertGradients', 'convertToGroup', 'setSvgString', 'importSvgString', 'identifyLayers', 'createLayer', 'cloneLayer', 'deleteCurrentLayer', 'setCurrentLayer', 'renameCurrentLayer', 'setCurrentLayerPosition', 'setLayerVisibility', 'moveSelectedToLayer', 'mergeLayer', 'mergeAllLayers', 'leaveContext', 'setContext', 'clear', 'linkControlPoints', 'getContentElem', 'getRootElem', 'getSelectedElems', 'getResolution', 'getZoom', 'getVersion', 'setUiStrings', 'setConfig', 'getTitle', 'setGroupTitle', 'getDocumentTitle', 'setDocumentTitle', 'getEditorNS', 'setResolution', 'getOffset', 'setBBoxZoom', 'setZoom', 'getMode', 'setMode', 'getColor', 'setColor', 'setGradient', 'setPaint', 'setStrokePaint', 'setFillPaint', 'getStrokeWidth', 'setStrokeWidth', 'setStrokeAttr', 'getStyle', 'getOpacity', 'setOpacity', 'getFillOpacity', 'getStrokeOpacity', 'setPaintOpacity', 'getPaintOpacity', 'getBlur', 'setBlurNoUndo', 'setBlurOffsets', 'setBlur', 'getBold', 'setBold', 'getItalic', 'setItalic', 'getFontFamily', 'setFontFamily', 'setFontColor', 'getFontColor', 'getFontSize', 'setFontSize', 'getText', 'setTextContent', 'setImageURL', 'setLinkURL', 'setRectRadius', 'makeHyperlink', 'removeHyperlink', 'setSegType', 'convertToPath', 'changeSelectedAttribute', 'deleteSelectedElements', 'cutSelectedElements', 'copySelectedElements', 'pasteElements', 'groupSelectedElements', 'pushGroupProperties', 'ungroupSelectedElement', 'moveToTopSelectedElement', 'moveToBottomSelectedElement', 'moveUpDownSelected', 'moveSelectedElements', 'cloneSelectedElements', 'alignSelectedElements', 'updateCanvas', 'setBackground', 'cycleElement', 'getPrivateMethods', 'zoomChanged', 'ready'
	];

  // TODO: rewrite the following, it's pretty scary.
  for (i = 0; i < functions.length; i++) {
    this[functions[i]] = getCallbackSetter(functions[i]);
  }
 
  // Older IE may need a polyfill for addEventListener, but so it would for SVG
  window.addEventListener('message', getMessageListener(this), false);
}

EmbeddedSVGEdit.prototype.send = function (name, args, callback){
  var t = this;
  cbid++;

  this.callbacks[cbid] = callback;
  setTimeout((function (cbid) {
	return function () { // Delay for the callback to be set in case its synchronous
		/*
		* Todo: Handle non-JSON arguments and return values (undefined,
		*   nonfinite numbers, functions, and built-in objects like Date,
		*   RegExp), etc.? Allow promises instead of callbacks? Review
		*   SVG-Edit functions for whether JSON-able parameters can be
		*   made compatile with all API functionality
		*/
		// We accept and post strings for the sake of IE9 support
		if (window.location.origin === t.frame.contentWindow.location.origin) {
		  // Although we do not really need this API if we are working same
		  //  domain, it could allow us to write in a way that would work
		  //  cross-domain as well, assuming we stick to the argument limitations
		  //  of the current JSON-based communication API (e.g., not passing
		  //  callbacks). We might be able to address these shortcomings; see
		  //  the todo elsewhere in this file.
		  var message = {id: cbid},
			svgCanvas = t.frame.contentWindow.svgCanvas;
		  try {
			message.result = svgCanvas[name].apply(svgCanvas, args);
		  }
		  catch (err) {
			message.error = err.message;
		  }
		  addCallback(t, message);
		}
		else { // Requires the ext-xdomain-messaging.js extension
		  t.frame.contentWindow.postMessage(JSON.stringify({namespace: 'svgCanvas', id: cbid, name: name, args: args}), '*');
		}
	  };
  }(cbid)), 0);

  return cbid;
};

window.embedded_svg_edit = EmbeddedSVGEdit; // Export old, deprecated API
window.EmbeddedSVGEdit = EmbeddedSVGEdit; // Follows common JS convention of CamelCase and, as enforced in JSLint, of initial caps for constructors

}());
