/** @preserve 
  jsPDF addImage plugin (JPEG only at this time)
  Copyright (c) 2012 https://github.com/siefkenj/
  */
  
  /**
   * Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the
   * "Software"), to deal in the Software without restriction, including
   * without limitation the rights to use, copy, modify, merge, publish,
   * distribute, sublicense, and/or sell copies of the Software, and to
   * permit persons to whom the Software is furnished to do so, subject to
   * the following conditions:
   * 
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   * 
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   * ====================================================================
   */
  
  ;(function(jsPDFAPI) {
  'use strict'
  
  var namespace = 'addImage_'
  
  // takes a string imgData containing the raw bytes of
  // a jpeg image and returns [width, height]
  // Algorithm from: http://www.64lines.com/jpeg-width-height
  var getJpegSize = function(imgData) {
  	'use strict'
  	var width, height;
  	// Verify we have a valid jpeg header 0xff,0xd8,0xff,0xe0,?,?,'J','F','I','F',0x00
  	if (!imgData.charCodeAt(0) === 0xff ||
  		!imgData.charCodeAt(1) === 0xd8 ||
  		!imgData.charCodeAt(2) === 0xff ||
  		!imgData.charCodeAt(3) === 0xe0 ||
  		!imgData.charCodeAt(6) === 'J'.charCodeAt(0) ||
  		!imgData.charCodeAt(7) === 'F'.charCodeAt(0) ||
  		!imgData.charCodeAt(8) === 'I'.charCodeAt(0) ||
  		!imgData.charCodeAt(9) === 'F'.charCodeAt(0) ||
  		!imgData.charCodeAt(10) === 0x00) {
  			throw new Error('getJpegSize requires a binary jpeg file')
  	}
  	var blockLength = imgData.charCodeAt(4)*256 + imgData.charCodeAt(5);
  	var i = 4, len = imgData.length;
  	while ( i < len ) {
  		i += blockLength;
  		if (imgData.charCodeAt(i) !== 0xff) {
  			throw new Error('getJpegSize could not find the size of the image');
  		}
  		if (imgData.charCodeAt(i+1) === 0xc0 || //(SOF) Huffman  - Baseline DCT
  		    imgData.charCodeAt(i+1) === 0xc1 || //(SOF) Huffman  - Extended sequential DCT 
  		    imgData.charCodeAt(i+1) === 0xc2 || // Progressive DCT (SOF2)
  		    imgData.charCodeAt(i+1) === 0xc3 || // Spatial (sequential) lossless (SOF3)
  		    imgData.charCodeAt(i+1) === 0xc4 || // Differential sequential DCT (SOF5)
  		    imgData.charCodeAt(i+1) === 0xc5 || // Differential progressive DCT (SOF6)
  		    imgData.charCodeAt(i+1) === 0xc6 || // Differential spatial (SOF7)
  		    imgData.charCodeAt(i+1) === 0xc7) {
  			height = imgData.charCodeAt(i+5)*256 + imgData.charCodeAt(i+6);
  			width = imgData.charCodeAt(i+7)*256 + imgData.charCodeAt(i+8);
  			return [width, height];
  		} else {
  			i += 2;
  			blockLength = imgData.charCodeAt(i)*256 + imgData.charCodeAt(i+1)
  		}
  	}
  }
  // Image functionality ported from pdf.js
  , putImage = function(img) {
  	var objectNumber = this.internal.newObject()
  	, out = this.internal.write
  	, putStream = this.internal.putStream
  
  	img['n'] = objectNumber
  
  	out('<</Type /XObject')
  	out('/Subtype /Image')
  	out('/Width ' + img['w'])
  	out('/Height ' + img['h'])
  	if (img['cs'] === 'Indexed') {
  		out('/ColorSpace [/Indexed /DeviceRGB '
  				+ (img['pal'].length / 3 - 1) + ' ' + (objectNumber + 1)
  				+ ' 0 R]');
  	} else {
  		out('/ColorSpace /' + img['cs']);
  		if (img['cs'] === 'DeviceCMYK') {
  			out('/Decode [1 0 1 0 1 0 1 0]');
  		}
  	}
  	out('/BitsPerComponent ' + img['bpc']);
  	if ('f' in img) {
  		out('/Filter /' + img['f']);
  	}
  	if ('dp' in img) {
  		out('/DecodeParms <<' + img['dp'] + '>>');
  	}
  	if ('trns' in img && img['trns'].constructor == Array) {
  		var trns = '';
  		for ( var i = 0; i < img['trns'].length; i++) {
  			trns += (img[trns][i] + ' ' + img['trns'][i] + ' ');
  			out('/Mask [' + trns + ']');
  		}
  	}
  	if ('smask' in img) {
  		out('/SMask ' + (objectNumber + 1) + ' 0 R');
  	}
  	out('/Length ' + img['data'].length + '>>');
  
  	putStream(img['data']);
  
  	out('endobj');
  }
  , putResourcesCallback = function() {
  	var images = this.internal.collections[namespace + 'images']
  	for ( var i in images ) {
  		putImage.call(this, images[i])
  	}
  }
  , putXObjectsDictCallback = function(){
  	var images = this.internal.collections[namespace + 'images']
  	, out = this.internal.write
  	, image
  	for (var i in images) {
  		image = images[i]
  		out(
  			'/I' + image['i']
  			, image['n']
  			, '0'
  			, 'R'
  		)
  	}
  }
  
  jsPDFAPI.addImage = function(imageData, format, x, y, w, h) {
  	'use strict'
  	if (typeof imageData === 'object' && imageData.nodeType === 1) {
          var canvas = document.createElement('canvas');
          canvas.width = imageData.clientWidth;
  	    canvas.height = imageData.clientHeight;
  
          var ctx = canvas.getContext('2d');
          if (!ctx) {
              throw ('addImage requires canvas to be supported by browser.');
          }
          ctx.drawImage(imageData, 0, 0, canvas.width, canvas.height);
          imageData = canvas.toDataURL('image/jpeg');
  	    format = "JPEG";
  	}
  	if (format.toUpperCase() !== 'JPEG') {
  		throw new Error('addImage currently only supports format \'JPEG\', not \''+format+'\'');
  	}
  
  	var imageIndex
  	, images = this.internal.collections[namespace + 'images']
  	, coord = this.internal.getCoordinateString
  	, vcoord = this.internal.getVerticalCoordinateString;
  
  	// Detect if the imageData is raw binary or Data URL
  	if (imageData.substring(0, 23) === 'data:image/jpeg;base64,') {
  		imageData = atob(imageData.replace('data:image/jpeg;base64,', ''));
  	}
  
  	if (images){
  		// this is NOT the first time this method is ran on this instance of jsPDF object.
  		imageIndex = Object.keys ? 
  		Object.keys(images).length :
  		(function(o){
  			var i = 0
  			for (var e in o){if(o.hasOwnProperty(e)){ i++ }}
  			return i
  		})(images)
  	} else {
  		// this is the first time this method is ran on this instance of jsPDF object.
  		imageIndex = 0
  		this.internal.collections[namespace + 'images'] = images = {}
  		this.internal.events.subscribe('putResources', putResourcesCallback)
  		this.internal.events.subscribe('putXobjectDict', putXObjectsDictCallback)
  	}
  
  	var dims = getJpegSize(imageData);
  	var info = {
  		w : dims[0],
  		h : dims[1],
  		cs : 'DeviceRGB',
  		bpc : 8,
  		f : 'DCTDecode',
  		i : imageIndex,
  		data : imageData
  		// n: objectNumber will be added by putImage code
  
  	};
  	images[imageIndex] = info
  	if (!w && !h) {
  		w = -96;
  		h = -96;
  	}
  	if (w < 0) {
  		w = (-1) * info['w'] * 72 / w / this.internal.scaleFactor;
  	}
  	if (h < 0) {
  		h = (-1) * info['h'] * 72 / h / this.internal.scaleFactor;
  	}
  	if (w === 0) {
  		w = h * info['w'] / info['h'];
  	}
  	if (h === 0) {
  		h = w * info['h'] / info['w'];
  	}
  
  	this.internal.write(
  		'q'
  		, coord(w)
  		, '0 0'
  		, coord(h) // TODO: check if this should be shifted by vcoord
  		, coord(x)
  		, vcoord(y + h)
  		, 'cm /I'+info['i']
  		, 'Do Q'
  	)
  
  	return this 
  }
  })(jsPDF.API)