/* global FlateStream */
// Generated by CoffeeScript 1.4.0

/*
# PNG.js
# Copyright (c) 2011 Devon Govett
# MIT LICENSE
# 
# 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 (global) {
  global.PNG = (function () {
    var APNG_BLEND_OP_OVER, APNG_BLEND_OP_SOURCE, APNG_DISPOSE_OP_BACKGROUND, APNG_DISPOSE_OP_NONE, APNG_DISPOSE_OP_PREVIOUS, makeImage, scratchCanvas, scratchCtx;

    APNG_DISPOSE_OP_NONE = 0;

    APNG_DISPOSE_OP_BACKGROUND = 1;

    APNG_DISPOSE_OP_PREVIOUS = 2;

    APNG_BLEND_OP_SOURCE = 0;

    APNG_BLEND_OP_OVER = 1;

    function PNG(data) {
      var chunkSize, colors, palLen, delayDen, delayNum, frame, i, index, key, section, palShort, text, _i, _j, _ref;
      this.data = data;
      this.pos = 8;
      this.palette = [];
      this.imgData = [];
      this.transparency = {};
      this.animation = null;
      this.text = {};
      frame = null;
      while (true) {
        chunkSize = this.readUInt32();
        section = ((function () {
          var _i, _results;
          _results = [];
          for (i = _i = 0; _i < 4; i = ++_i) {
            _results.push(String.fromCharCode(this.data[this.pos++]));
          }
          return _results;
        }).call(this)).join('');
        switch (section) {
          case 'IHDR':
            this.width = this.readUInt32();
            this.height = this.readUInt32();
            this.bits = this.data[this.pos++];
            this.colorType = this.data[this.pos++];
            this.compressionMethod = this.data[this.pos++];
            this.filterMethod = this.data[this.pos++];
            this.interlaceMethod = this.data[this.pos++];
            break;
          case 'acTL':
            this.animation = {
              numFrames: this.readUInt32(),
              numPlays: this.readUInt32() || Infinity,
              frames: []
            };
            break;
          case 'PLTE':
            this.palette = this.read(chunkSize);
            break;
          case 'fcTL':
            if (frame) {
              this.animation.frames.push(frame);
            }
            this.pos += 4;
            frame = {
              width: this.readUInt32(),
              height: this.readUInt32(),
              xOffset: this.readUInt32(),
              yOffset: this.readUInt32()
            };
            delayNum = this.readUInt16();
            delayDen = this.readUInt16() || 100;
            frame.delay = 1000 * delayNum / delayDen;
            frame.disposeOp = this.data[this.pos++];
            frame.blendOp = this.data[this.pos++];
            frame.data = [];
            break;
          case 'IDAT':
          case 'fdAT':
            if (section === 'fdAT') {
              this.pos += 4;
              chunkSize -= 4;
            }
            data = (frame != null ? frame.data : void 0) || this.imgData;
            for (i = _i = 0; 0 <= chunkSize ? _i < chunkSize : _i > chunkSize; i = 0 <= chunkSize ? ++_i : --_i) {
              data.push(this.data[this.pos++]);
            }
            break;
          case 'tRNS':
            this.transparency = {};
            switch (this.colorType) {
              case 3:
                palLen = this.palette.length / 3;
                this.transparency.indexed = this.read(chunkSize);
                if (this.transparency.indexed.length > palLen)
                  throw new Error('More transparent colors than palette size');
                /*
                 * According to the PNG spec trns should be increased to the same size as palette if shorter
                 */
                //palShort = 255 - this.transparency.indexed.length;
                palShort = palLen - this.transparency.indexed.length;
                if (palShort > 0) {
                  for (i = _j = 0; 0 <= palShort ? _j < palShort : _j > palShort; i = 0 <= palShort ? ++_j : --_j) {
                    this.transparency.indexed.push(255);
                  }
                }
                break;
              case 0:
                this.transparency.grayscale = this.read(chunkSize)[0];
                break;
              case 2:
                this.transparency.rgb = this.read(chunkSize);
            }
            break;
          case 'tEXt':
            text = this.read(chunkSize);
            index = text.indexOf(0);
            key = String.fromCharCode.apply(String, text.slice(0, index));
            this.text[key] = String.fromCharCode.apply(String, text.slice(index + 1));
            break;
          case 'IEND':
            if (frame) {
              this.animation.frames.push(frame);
            }
            this.colors = (function () {
              switch (this.colorType) {
                case 0:
                case 3:
                case 4:
                  return 1;
                case 2:
                case 6:
                  return 3;
              }
            }).call(this);
            this.hasAlphaChannel = (_ref = this.colorType) === 4 || _ref === 6;
            colors = this.colors + (this.hasAlphaChannel ? 1 : 0);
            this.pixelBitlength = this.bits * colors;
            this.colorSpace = (function () {
              switch (this.colors) {
                case 1:
                  return 'DeviceGray';
                case 3:
                  return 'DeviceRGB';
              }
            }).call(this);
            this.imgData = new Uint8Array(this.imgData);
            return;
          default:
            this.pos += chunkSize;
        }
        this.pos += 4;
        if (this.pos > this.data.length) {
          throw new Error("Incomplete or corrupt PNG file");
        }
      }
    }

    PNG.prototype.read = function (bytes) {
      var i, _i, _results;
      _results = [];
      for (i = _i = 0; 0 <= bytes ? _i < bytes : _i > bytes; i = 0 <= bytes ? ++_i : --_i) {
        _results.push(this.data[this.pos++]);
      }
      return _results;
    };

    PNG.prototype.readUInt32 = function () {
      var b1, b2, b3, b4;
      b1 = this.data[this.pos++] << 24;
      b2 = this.data[this.pos++] << 16;
      b3 = this.data[this.pos++] << 8;
      b4 = this.data[this.pos++];
      return b1 | b2 | b3 | b4;
    };

    PNG.prototype.readUInt16 = function () {
      var b1, b2;
      b1 = this.data[this.pos++] << 8;
      b2 = this.data[this.pos++];
      return b1 | b2;
    };


    PNG.prototype.decodePixels = function (data) {
      var pixelBytes = this.pixelBitlength / 8;
      var fullPixels = new Uint8Array(this.width * this.height * pixelBytes);
      var pos = 0;
      var _this = this;

      if (data == null) {
        data = this.imgData;
      }
      if (data.length === 0) {
        return new Uint8Array(0);
      }

      data = new FlateStream(data);
      data = data.getBytes();
      function pass(x0, y0, dx, dy) {
        var abyte, c, col, i, left, length, p, pa, paeth, pb, pc, pixels, row, scanlineLength, upper, upperLeft, _i, _j, _k, _l, _m;
        var w = Math.ceil((_this.width - x0) / dx), h = Math.ceil((_this.height - y0) / dy);
        var isFull = _this.width == w && _this.height == h;
        scanlineLength = pixelBytes * w;
        pixels = isFull ? fullPixels : new Uint8Array(scanlineLength * h);
        length = data.length;
        row = 0;
        c = 0;
        while (row < h && pos < length) {
          switch (data[pos++]) {
            case 0:
              for (i = _i = 0; _i < scanlineLength; i = _i += 1) {
                pixels[c++] = data[pos++];
              }
              break;
            case 1:
              for (i = _j = 0; _j < scanlineLength; i = _j += 1) {
                abyte = data[pos++];
                left = i < pixelBytes ? 0 : pixels[c - pixelBytes];
                pixels[c++] = (abyte + left) % 256;
              }
              break;
            case 2:
              for (i = _k = 0; _k < scanlineLength; i = _k += 1) {
                abyte = data[pos++];
                col = (i - (i % pixelBytes)) / pixelBytes;
                upper = row && pixels[(row - 1) * scanlineLength + col * pixelBytes + (i % pixelBytes)];
                pixels[c++] = (upper + abyte) % 256;
              }
              break;
            case 3:
              for (i = _l = 0; _l < scanlineLength; i = _l += 1) {
                abyte = data[pos++];
                col = (i - (i % pixelBytes)) / pixelBytes;
                left = i < pixelBytes ? 0 : pixels[c - pixelBytes];
                upper = row && pixels[(row - 1) * scanlineLength + col * pixelBytes + (i % pixelBytes)];
                pixels[c++] = (abyte + Math.floor((left + upper) / 2)) % 256;
              }
              break;
            case 4:
              for (i = _m = 0; _m < scanlineLength; i = _m += 1) {
                abyte = data[pos++];
                col = (i - (i % pixelBytes)) / pixelBytes;
                left = i < pixelBytes ? 0 : pixels[c - pixelBytes];
                if (row === 0) {
                  upper = upperLeft = 0;
                } else {
                  upper = pixels[(row - 1) * scanlineLength + col * pixelBytes + (i % pixelBytes)];
                  upperLeft = col && pixels[(row - 1) * scanlineLength + (col - 1) * pixelBytes + (i % pixelBytes)];
                }
                p = left + upper - upperLeft;
                pa = Math.abs(p - left);
                pb = Math.abs(p - upper);
                pc = Math.abs(p - upperLeft);
                if (pa <= pb && pa <= pc) {
                  paeth = left;
                } else if (pb <= pc) {
                  paeth = upper;
                } else {
                  paeth = upperLeft;
                }
                pixels[c++] = (abyte + paeth) % 256;
              }
              break;
            default:
              throw new Error("Invalid filter algorithm: " + data[pos - 1]);
          }
          if (!isFull) {
            var fullPos = ((y0 + row * dy) * _this.width + x0) * pixelBytes;
            var partPos = row * scanlineLength;
            for (i = 0; i < w; i += 1) {
              for (var j = 0; j < pixelBytes; j += 1)
                fullPixels[fullPos++] = pixels[partPos++];
              fullPos += (dx - 1) * pixelBytes;
            }
          }
          row++;
        }
      }
      if (_this.interlaceMethod == 1) {
        /*
          1 6 4 6 2 6 4 6
          7 7 7 7 7 7 7 7
          5 6 5 6 5 6 5 6
          7 7 7 7 7 7 7 7
          3 6 4 6 3 6 4 6
          7 7 7 7 7 7 7 7
          5 6 5 6 5 6 5 6
          7 7 7 7 7 7 7 7
        */
        pass(0, 0, 8, 8); // 1
        /* NOTE these seem to follow the pattern:
         * pass(x, 0, 2*x, 2*x);
         * pass(0, x,   x, 2*x);
         * with x being 4, 2, 1.
         */
        pass(4, 0, 8, 8); // 2
        pass(0, 4, 4, 8); // 3

        pass(2, 0, 4, 4); // 4
        pass(0, 2, 2, 4); // 5

        pass(1, 0, 2, 2); // 6
        pass(0, 1, 1, 2); // 7
      } else {
        pass(0, 0, 1, 1);
      }
      return fullPixels;
    };

    PNG.prototype.decodePalette = function () {
      var c, i, length, palette, pos, ret, transparency, _i, _ref, _ref1;
      palette = this.palette;
      transparency = this.transparency.indexed || [];
      ret = new Uint8Array((transparency.length || 0) + palette.length);
      pos = 0;
      length = palette.length;
      c = 0;
      for (i = _i = 0, _ref = length; _i < _ref; i = _i += 3) {
        ret[pos++] = palette[i];
        ret[pos++] = palette[i + 1];
        ret[pos++] = palette[i + 2];
        ret[pos++] = (_ref1 = transparency[c++]) != null ? _ref1 : 255;
      }
      return ret;
    };

    PNG.prototype.copyToImageData = function (imageData, pixels) {
      var alpha, colors, data, i, input, j, k, length, palette, v, _ref;
      colors = this.colors;
      palette = null;
      alpha = this.hasAlphaChannel;
      if (this.palette.length) {
        palette = (_ref = this._decodedPalette) != null ? _ref : this._decodedPalette = this.decodePalette();
        colors = 4;
        alpha = true;
      }
      data = imageData.data || imageData;
      length = data.length;
      input = palette || pixels;
      i = j = 0;
      if (colors === 1) {
        while (i < length) {
          k = palette ? pixels[i / 4] * 4 : j;
          v = input[k++];
          data[i++] = v;
          data[i++] = v;
          data[i++] = v;
          data[i++] = alpha ? input[k++] : 255;
          j = k;
        }
      } else {
        while (i < length) {
          k = palette ? pixels[i / 4] * 4 : j;
          data[i++] = input[k++];
          data[i++] = input[k++];
          data[i++] = input[k++];
          data[i++] = alpha ? input[k++] : 255;
          j = k;
        }
      }
    };

    PNG.prototype.decode = function () {
      var ret;
      ret = new Uint8Array(this.width * this.height * 4);
      this.copyToImageData(ret, this.decodePixels());
      return ret;
    };

    var hasBrowserCanvas = function () {
      if (Object.prototype.toString.call(global) === "[object Window]") {
        try {
          scratchCanvas = global.document.createElement('canvas');
          scratchCtx = scratchCanvas.getContext('2d');
        } catch (e) {
          return false;
        }
        return true;
      }
      return false;
    }

    hasBrowserCanvas();

    makeImage = function (imageData) {
      if (hasBrowserCanvas() === true) {
        var img;
        scratchCtx.width = imageData.width;
        scratchCtx.height = imageData.height;
        scratchCtx.clearRect(0, 0, imageData.width, imageData.height);
        scratchCtx.putImageData(imageData, 0, 0);
        img = new Image;
        img.src = scratchCanvas.toDataURL();
        return img;
      }
      throw new Error('This method requires a Browser with Canvas-capability.');
    };

    PNG.prototype.decodeFrames = function (ctx) {
      var frame, i, imageData, pixels, _i, _len, _ref, _results;
      if (!this.animation) {
        return;
      }
      _ref = this.animation.frames;
      _results = [];
      for (i = _i = 0, _len = _ref.length; _i < _len; i = ++_i) {
        frame = _ref[i];
        imageData = ctx.createImageData(frame.width, frame.height);
        pixels = this.decodePixels(new Uint8Array(frame.data));
        this.copyToImageData(imageData, pixels);
        frame.imageData = imageData;
        _results.push(frame.image = makeImage(imageData));
      }
      return _results;
    };

    PNG.prototype.renderFrame = function (ctx, number) {
      var frame, frames, prev;
      frames = this.animation.frames;
      frame = frames[number];
      prev = frames[number - 1];
      if (number === 0) {
        ctx.clearRect(0, 0, this.width, this.height);
      }
      if ((prev != null ? prev.disposeOp : void 0) === APNG_DISPOSE_OP_BACKGROUND) {
        ctx.clearRect(prev.xOffset, prev.yOffset, prev.width, prev.height);
      } else if ((prev != null ? prev.disposeOp : void 0) === APNG_DISPOSE_OP_PREVIOUS) {
        ctx.putImageData(prev.imageData, prev.xOffset, prev.yOffset);
      }
      if (frame.blendOp === APNG_BLEND_OP_SOURCE) {
        ctx.clearRect(frame.xOffset, frame.yOffset, frame.width, frame.height);
      }
      return ctx.drawImage(frame.image, frame.xOffset, frame.yOffset);
    };

    PNG.prototype.animate = function (ctx) {
      var doFrame, frameNumber, frames, numFrames, numPlays, _ref,
        _this = this;
      frameNumber = 0;
      _ref = this.animation, numFrames = _ref.numFrames, frames = _ref.frames, numPlays = _ref.numPlays;
      return (doFrame = function () {
        var f, frame;
        f = frameNumber++ % numFrames;
        frame = frames[f];
        _this.renderFrame(ctx, f);
        if (numFrames > 1 && frameNumber / numFrames < numPlays) {
          return _this.animation._timeout = setTimeout(doFrame, frame.delay);
        }
      })();
    };

    PNG.prototype.stopAnimation = function () {
      var _ref;
      return clearTimeout((_ref = this.animation) != null ? _ref._timeout : void 0);
    };

    PNG.prototype.render = function (canvas) {
      var ctx, data;
      if (canvas._png) {
        canvas._png.stopAnimation();
      }
      canvas._png = this;
      canvas.width = this.width;
      canvas.height = this.height;
      ctx = canvas.getContext("2d");
      if (this.animation) {
        this.decodeFrames(ctx);
        return this.animate(ctx);
      } else {
        data = ctx.createImageData(this.width, this.height);
        this.copyToImageData(data, this.decodePixels());
        return ctx.putImageData(data, 0, 0);
      }
    };

    return PNG;

  })();

}(typeof self !== "undefined" && self || typeof window !== "undefined" && window || typeof global !== "undefined" && global || Function('return typeof this === "object" && this.content')() || Function('return this')()));
// `self` is undefined in Firefox for Android content script context
// while `this` is nsIContentFrameMessageManager
// with an attribute `content` that corresponds to the window
