/*
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
    };
  };
}

function EmbeddedSVGEdit(frame){
  if (!(this instanceof EmbeddedSVGEdit)) { // Allow invocation without "new" keyword
    return new EmbeddedSVGEdit(frame);
  }
  // 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 l = []; for (var i in svgCanvas){ if (typeof svgCanvas[i] == "function") { l.push(i);} };
  // Run in svgedit itself
  var i,
    t = this,
    functions = ["updateElementFromJson", "embedImage", "fixOperaXML", "clearSelection",
      "addToSelection",
      "removeFromSelection", "addNodeToSelection", "open", "save", "getSvgString", "setSvgString", "createLayer",
      "deleteCurrentLayer", "getCurrentDrawing", "setCurrentLayer", "renameCurrentLayer", "setCurrentLayerPosition",
      "setLayerVisibility", "moveSelectedToLayer", "clear", "clearPath", "getNodePoint", "clonePathNode", "deletePathNode",
      "getResolution", "getImageTitle", "setImageTitle", "setResolution", "setBBoxZoom", "setZoom", "getMode", "setMode",
      "getStrokeColor", "setStrokeColor", "getFillColor", "setFillColor", "setStrokePaint", "setFillPaint", "getStrokeWidth",
      "setStrokeWidth", "getStrokeStyle", "setStrokeStyle", "getOpacity", "setOpacity", "getFillOpacity", "setFillOpacity",
      "getStrokeOpacity", "setStrokeOpacity", "getTransformList", "getBBox", "getRotationAngle", "setRotationAngle", "each",
      "bind", "setIdPrefix", "getBold", "setBold", "getItalic", "setItalic", "getFontFamily", "setFontFamily", "getFontSize",
      "setFontSize", "getText", "setTextContent", "setImageURL", "setRectRadius", "setSegType", "quickClone",
      "changeSelectedAttributeNoUndo", "changeSelectedAttribute", "deleteSelectedElements", "groupSelectedElements", "zoomChanged",
      "ungroupSelectedElement", "moveToTopSelectedElement", "moveToBottomSelectedElement", "moveSelectedElements",
      "getStrokedBBox", "getVisibleElements", "cycleElement", "getUndoStackSize", "getRedoStackSize", "getNextUndoCommandText",
      "getNextRedoCommandText", "undo", "redo", "cloneSelectedElements", "alignSelectedElements", "getZoom", "getVersion",
      "setIconSize", "setLang", "setCustomHandlers"];

  // 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', function(e) {
    // We accept and post strings as opposed to objets for the sake of IE9 support; this
    //   will most likely be changed in the future
    if (typeof e.data !== 'string') {
      return;
    }
    var result, cbid,
      data = e.data && JSON.parse(e.data);
    if (!data || typeof data !== 'object' || data.namespace !== 'svg-edit') {
      return;
    }
    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");
      }
    }
  }, false);
}

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

  this.callbacks[cbid] = callback;
  setTimeout(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.?
    // We accept and post strings for the sake of IE9 support
    t.frame.contentWindow.postMessage(JSON.stringify({namespace: "svgCanvas", id: cbid, name: name, args: args}), '*');
  }, 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

}());
