// Canvas doesn't support getCoords() which I really need....
// So I made a wrapper, code mostly taken from excanvas.js by Google - http://code.google.com/p/explorercanvas/
// alias some functions to make (compiled) code shorter
var m = Math;
var mr = m.round;
var ms = m.sin;
var mc = m.cos;
var abs = m.abs;
var sqrt = m.sqrt;
function createMatrixIdentity() {
  return [
    [1, 0, 0],
    [0, 1, 0],
    [0, 0, 1]
  ];
}
function matrixMultiply(m1, m2) {
  var result = createMatrixIdentity();
  for (var x = 0; x < 3; x++) {
    for (var y = 0; y < 3; y++) {
      var sum = 0;
      for (var z = 0; z < 3; z++) {
        sum += m1[x][z] * m2[z][y];
      }
      result[x][y] = sum;
    }
  }
  return result;
}
function copyState(o1, o2) {
  o2.fillStyle = o1.fillStyle;
  o2.lineCap = o1.lineCap;
  o2.lineJoin = o1.lineJoin;
  o2.lineWidth = o1.lineWidth;
  o2.miterLimit = o1.miterLimit;
  o2.shadowBlur = o1.shadowBlur;
  o2.shadowColor = o1.shadowColor;
  o2.shadowOffsetX = o1.shadowOffsetX;
  o2.shadowOffsetY = o1.shadowOffsetY;
  o2.strokeStyle = o1.strokeStyle;
  o2.globalAlpha = o1.globalAlpha;
}
function CanvasWrapper(ctx) {
  this.m_ = createMatrixIdentity();
  this.mStack_ = [];
  this.aStack_ = [];
  this.canvas = ctx;
  // Canvas context properties
  this.strokeStyle = '#000';
  this.fillStyle = '#000';
  this.lineWidth = 1;
  this.lineJoin = 'miter';
  this.lineCap = 'butt';
  this.miterLimit = 1;
  this.globalAlpha = 1;
}
var cwPrototype = CanvasWrapper.prototype;
cwPrototype.applyContextProperties = function () {
  this.canvas.strokeStyle = this.strokeStyle;
  this.canvas.fillStyle = this.fillStyle;
  this.canvas.lineWidth = this.lineWidth;
  this.canvas.lineJoin = this.lineJoin;
  this.canvas.lineCap = this.lineCap;
  this.canvas.miterLimit = this.miterLimit;
  this.canvas.globalAlpha = this.globalAlpha;
};
cwPrototype.beginPath = function () {
  this.canvas.beginPath();
};
cwPrototype.moveTo = function (aX, aY) {
  this.canvas.moveTo(aX, aY);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.lineTo = function (aX, aY) {
  this.applyContextProperties();
  this.canvas.lineTo(aX, aY);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.bezierCurveTo = function (aCP1x, aCP1y, aCP2x, aCP2y, aX, aY) {
  this.applyContextProperties();
  this.canvas.bezierCurveTo(aCP1x, aCP1y, aCP2x, aCP2y, aX, aY);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.quadraticCurveTo = function (aCPx, aCPy, aX, aY) {
  this.applyContextProperties();
  this.canvas.quadraticCurveTo(aCPx, aCPy, aX, aY);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.arc = function (aX, aY, aRadius, aStartAngle, aEndAngle, aClockwise) {
  this.applyContextProperties();
  this.canvas.arc(aX, aY, aRadius, aStartAngle, aEndAngle, aClockwise);
};
cwPrototype.rect = function (aX, aY, aWidth, aHeight) {
  this.applyContextProperties();
  this.canvas.rect(aX, aY, aWidth, aHeight);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.strokeRect = function (aX, aY, aWidth, aHeight) {
  this.applyContextProperties();
  this.canvas.strokeRect(aX, aY, aWidth, aHeight);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.fillRect = function (aX, aY, aWidth, aHeight) {
  this.applyContextProperties();
  this.canvas.fillRect(aX, aY, aWidth, aHeight);
  var p = this.getCoords(aX, aY);
  this.currentX_ = p.x;
  this.currentY_ = p.y;
};
cwPrototype.createLinearGradient = function (aX0, aY0, aX1, aY1) {
  this.applyContextProperties();
  return this.canvas.createLinearGradient(aX0, aY0, aX1, aY1);
};
cwPrototype.createRadialGradient = function (aX0, aY0, aR0, aX1, aY1, aR1) {
  this.applyContextProperties();
  return this.canvas.createRadialGradient(aX0, aY0, aR0, aX1, aY1, aR1);
};
cwPrototype.stroke = function (aFill) {
  this.applyContextProperties();
  this.canvas.stroke(aFill);
};
cwPrototype.fill = function () {
  this.applyContextProperties();
  this.canvas.fill();
}
cwPrototype.clearRect = function (aX, aY, aWidth, aHeight) {
  this.canvas.clearRect(aX, aY, aWidth, aHeight);
}
cwPrototype.closePath = function () {
  this.canvas.closePath();
};
cwPrototype.getCoords = function (aX, aY) {
  var m = this.m_;
  return {
    x: aX * m[0][0] + aY * m[1][0] + m[2][0],
    y: aX * m[0][1] + aY * m[1][1] + m[2][1]
  }
};
cwPrototype.save = function () {
  this.canvas.save();
  var o = {};
  copyState(this, o);
  this.aStack_.push(o);
  this.mStack_.push(this.m_);
  // is this a no-op?
  this.m_ = matrixMultiply(createMatrixIdentity(), this.m_);
};
cwPrototype.restore = function () {
  this.canvas.restore();
  copyState(this.aStack_.pop(), this);
  this.m_ = this.mStack_.pop();
};
function matrixIsFinite(m) {
  for (var j = 0; j < 3; j++) {
    for (var k = 0; k < 2; k++) {
      if (!isFinite(m[j][k]) || isNaN(m[j][k])) {
        return false;
      }
    }
  }
  return true;
}
function setM(ctx, m) {
  if (!matrixIsFinite(m)) {
    return;
  }
  ctx.m_ = m;
}

cwPrototype.setMatrix = function(matrix) {
  this.setTransform(matrix[0][0], matrix[0][1], matrix[1][0], matrix[1][1], matrix[2][0], matrix[2][1]);
}

cwPrototype.getMatrix = function() {
  return this.m_
}

cwPrototype.translate = function (aX, aY) {
  this.canvas.translate(aX, aY);
  var m1 = [
    [1, 0, 0],
    [0, 1, 0],
    [aX, aY, 1]
  ];
  setM(this, matrixMultiply(m1, this.m_));
};
cwPrototype.rotate = function (aRot) {
  this.canvas.rotate(aRot);
  var c = mc(aRot);
  var s = ms(aRot);
  var m1 = [
    [c, s, 0],
    [-s, c, 0],
    [0, 0, 1]
  ];
  setM(this, matrixMultiply(m1, this.m_));
};
cwPrototype.scale = function (aX, aY) {
  this.canvas.scale(aX, aY);
  var m1 = [
    [aX, 0, 0],
    [0, aY, 0],
    [0, 0, 1]
  ];
  setM(this, matrixMultiply(m1, this.m_));
};
cwPrototype.transform = function (m11, m12, m21, m22, dx, dy) {
  this.canvas.transform(m11, m12, m21, m22, dx, dy);
  var m1 = [
    [m11, m12, 0],
    [m21, m22, 0],
    [dx, dy, 1]
  ];
  setM(this, matrixMultiply(m1, this.m_));
};
cwPrototype.setTransform = function (m11, m12, m21, m22, dx, dy) {
  this.canvas.setTransform(m11, m12, m21, m22, dx, dy);
  var m = [
    [m11, m12, 0],
    [m21, m22, 0],
    [dx, dy, 1]
  ];
  setM(this, m);
};