/*!
 * Signature Pad v3.0.0-beta.3 | https://github.com/szimek/signature_pad
 * (c) 2018 Szymon Nowak | Released under the MIT license
 */

(function (global, factory) {
	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
	typeof define === 'function' && define.amd ? define(factory) :
	(global.SignaturePad = factory());
  }(this, (function () { 'use strict';

	var Point = (function () {
		function Point(x, y, time) {
			this.x = x;
			this.y = y;
			this.time = time || Date.now();
		}
		Point.prototype.distanceTo = function (start) {
			return Math.sqrt(Math.pow(this.x - start.x, 2) + Math.pow(this.y - start.y, 2));
		};
		Point.prototype.equals = function (other) {
			return this.x === other.x && this.y === other.y && this.time === other.time;
		};
		Point.prototype.velocityFrom = function (start) {
			return this.time !== start.time
				? this.distanceTo(start) / (this.time - start.time)
				: 0;
		};
		return Point;
	}());

	var Bezier = (function () {
		function Bezier(startPoint, control2, control1, endPoint, startWidth, endWidth) {
			this.startPoint = startPoint;
			this.control2 = control2;
			this.control1 = control1;
			this.endPoint = endPoint;
			this.startWidth = startWidth;
			this.endWidth = endWidth;
		}
		Bezier.fromPoints = function (points, widths) {
			var c2 = this.calculateControlPoints(points[0], points[1], points[2]).c2;
			var c3 = this.calculateControlPoints(points[1], points[2], points[3]).c1;
			return new Bezier(points[1], c2, c3, points[2], widths.start, widths.end);
		};
		Bezier.calculateControlPoints = function (s1, s2, s3) {
			var dx1 = s1.x - s2.x;
			var dy1 = s1.y - s2.y;
			var dx2 = s2.x - s3.x;
			var dy2 = s2.y - s3.y;
			var m1 = { x: (s1.x + s2.x) / 2.0, y: (s1.y + s2.y) / 2.0 };
			var m2 = { x: (s2.x + s3.x) / 2.0, y: (s2.y + s3.y) / 2.0 };
			var l1 = Math.sqrt(dx1 * dx1 + dy1 * dy1);
			var l2 = Math.sqrt(dx2 * dx2 + dy2 * dy2);
			var dxm = m1.x - m2.x;
			var dym = m1.y - m2.y;
			var k = l2 / (l1 + l2);
			var cm = { x: m2.x + dxm * k, y: m2.y + dym * k };
			var tx = s2.x - cm.x;
			var ty = s2.y - cm.y;
			return {
				c1: new Point(m1.x + tx, m1.y + ty),
				c2: new Point(m2.x + tx, m2.y + ty)
			};
		};
		Bezier.prototype.length = function () {
			var steps = 10;
			var length = 0;
			var px;
			var py;
			for (var i = 0; i <= steps; i += 1) {
				var t = i / steps;
				var cx = this.point(t, this.startPoint.x, this.control1.x, this.control2.x, this.endPoint.x);
				var cy = this.point(t, this.startPoint.y, this.control1.y, this.control2.y, this.endPoint.y);
				if (i > 0) {
					var xdiff = cx - px;
					var ydiff = cy - py;
					length += Math.sqrt(xdiff * xdiff + ydiff * ydiff);
				}
				px = cx;
				py = cy;
			}
			return length;
		};
		Bezier.prototype.point = function (t, start, c1, c2, end) {
			return (start * (1.0 - t) * (1.0 - t) * (1.0 - t))
				+ (3.0 * c1 * (1.0 - t) * (1.0 - t) * t)
				+ (3.0 * c2 * (1.0 - t) * t * t)
				+ (end * t * t * t);
		};
		return Bezier;
	}());

	function throttle(fn, wait) {
		if (wait === void 0) { wait = 250; }
		var previous = 0;
		var timeout = null;
		var result;
		var storedContext;
		var storedArgs;
		var later = function () {
			previous = Date.now();
			timeout = null;
			result = fn.apply(storedContext, storedArgs);
			if (!timeout) {
				storedContext = null;
				storedArgs = [];
			}
		};
		return function wrapper() {
			var args = [];
			for (var _i = 0; _i < arguments.length; _i++) {
				args[_i] = arguments[_i];
			}
			var now = Date.now();
			var remaining = wait - (now - previous);
			storedContext = this;
			storedArgs = args;
			if (remaining <= 0 || remaining > wait) {
				if (timeout) {
					clearTimeout(timeout);
					timeout = null;
				}
				previous = now;
				result = fn.apply(storedContext, storedArgs);
				if (!timeout) {
					storedContext = null;
					storedArgs = [];
				}
			}
			else if (!timeout) {
				timeout = window.setTimeout(later, remaining);
			}
			return result;
		};
	}

	var SignaturePad = (function () {
		function SignaturePad(canvas, options) {
			if (options === void 0) { options = {}; }
			var _this = this;
			this.canvas = canvas;
			this.options = options;
			this._handleMouseDown = function (event) {
				if (event.which === 1) {
					_this._mouseButtonDown = true;
					_this._strokeBegin(event);
				}
			};
			this._handleMouseMove = function (event) {
				if (_this._mouseButtonDown) {
					_this._strokeMoveUpdate(event);
				}
			};
			this._handleMouseUp = function (event) {
				if (event.which === 1 && _this._mouseButtonDown) {
					_this._mouseButtonDown = false;
					_this._strokeEnd(event);
				}
			};
			this._handleTouchStart = function (event) {
				event.preventDefault();
				if (event.targetTouches.length === 1) {
					var touch = event.changedTouches[0];
					_this._strokeBegin(touch);
				}
			};
			this._handleTouchMove = function (event) {
				event.preventDefault();
				var touch = event.targetTouches[0];
				_this._strokeMoveUpdate(touch);
			};
			this._handleTouchEnd = function (event) {
				var wasCanvasTouched = event.target === _this.canvas;
				if (wasCanvasTouched) {
					event.preventDefault();
					var touch = event.changedTouches[0];
					_this._strokeEnd(touch);
				}
			};
			this.velocityFilterWeight = options.velocityFilterWeight || 0.7;
			this.minWidth = options.minWidth || 0.5;
			this.maxWidth = options.maxWidth || 2.5;
			this.throttle = ('throttle' in options ? options.throttle : 16);
			this.minDistance = ('minDistance' in options
				? options.minDistance
				: 5);
			if (this.throttle) {
				this._strokeMoveUpdate = throttle(SignaturePad.prototype._strokeUpdate, this.throttle);
			}
			else {
				this._strokeMoveUpdate = SignaturePad.prototype._strokeUpdate;
			}
			this.dotSize =
				options.dotSize ||
					function dotSize() {
						return (this.minWidth + this.maxWidth) / 2;
					};
			this.penColor = options.penColor || 'black';
			this.backgroundColor = options.backgroundColor || 'rgba(0,0,0,0)';
			this.onBegin = options.onBegin;
			this.onEnd = options.onEnd;
			this._ctx = canvas.getContext('2d');
			this.clear();
			this.on();
		}
		SignaturePad.prototype.clear = function () {
			var ctx = this._ctx;
			var canvas = this.canvas;
			ctx.fillStyle = this.backgroundColor;
			ctx.clearRect(0, 0, canvas.width, canvas.height);
			ctx.fillRect(0, 0, canvas.width, canvas.height);
			this._data = [];
			this._reset();
			this._isEmpty = true;
		};
		SignaturePad.prototype.fromDataURL = function (dataUrl, options, callback) {
			var _this = this;
			if (options === void 0) { options = {}; }
			var image = new Image();
			var ratio = options.ratio || window.devicePixelRatio || 1;
			var width = options.width || this.canvas.width / ratio;
			var height = options.height || this.canvas.height / ratio;
			this._reset();
			image.onload = function () {
				_this._ctx.drawImage(image, 0, 0, width, height);
				if (callback) {
					callback();
				}
			};
			image.onerror = function (error) {
				if (callback) {
					callback(error);
				}
			};
			image.src = dataUrl;
			this._isEmpty = false;
		};
		SignaturePad.prototype.toDataURL = function (type, encoderOptions) {
			if (type === void 0) { type = 'image/png'; }
			switch (type) {
				case 'image/svg+xml':
					return this._toSVG();
				default:
					return this.canvas.toDataURL(type, encoderOptions);
			}
		};
		SignaturePad.prototype.on = function () {
			this.canvas.style.touchAction = 'none';
			this.canvas.style.msTouchAction = 'none';
			if (window.PointerEvent) {
				this._handlePointerEvents();
			}
			else {
				this._handleMouseEvents();
				if ('ontouchstart' in window) {
					this._handleTouchEvents();
				}
			}
		};
		SignaturePad.prototype.off = function () {
			this.canvas.style.touchAction = 'auto';
			this.canvas.style.msTouchAction = 'auto';
			this.canvas.removeEventListener('pointerdown', this._handleMouseDown);
			this.canvas.removeEventListener('pointermove', this._handleMouseMove);
			document.removeEventListener('pointerup', this._handleMouseUp);
			this.canvas.removeEventListener('mousedown', this._handleMouseDown);
			this.canvas.removeEventListener('mousemove', this._handleMouseMove);
			document.removeEventListener('mouseup', this._handleMouseUp);
			this.canvas.removeEventListener('touchstart', this._handleTouchStart);
			this.canvas.removeEventListener('touchmove', this._handleTouchMove);
			this.canvas.removeEventListener('touchend', this._handleTouchEnd);
		};
		SignaturePad.prototype.isEmpty = function () {
			return this._isEmpty;
		};
		SignaturePad.prototype.fromData = function (pointGroups) {
			var _this = this;
			this.clear();
			this._fromData(pointGroups, function (_a) {
				var color = _a.color, curve = _a.curve;
				return _this._drawCurve({ color: color, curve: curve });
			}, function (_a) {
				var color = _a.color, point = _a.point;
				return _this._drawDot({ color: color, point: point });
			});
			this._data = pointGroups;
		};
		SignaturePad.prototype.toData = function () {
			return this._data;
		};
		SignaturePad.prototype._strokeBegin = function (event) {
			var newPointGroup = {
				color: this.penColor,
				points: []
			};
			if (typeof this.onBegin === 'function') {
				this.onBegin(event);
			}
			this._data.push(newPointGroup);
			this._reset();
			this._strokeUpdate(event);
		};
		SignaturePad.prototype._strokeUpdate = function (event) {
			var x = event.clientX;
			var y = event.clientY;
			var point = this._createPoint(x, y);
			var lastPointGroup = this._data[this._data.length - 1];
			var lastPoints = lastPointGroup.points;
			var lastPoint = lastPoints.length > 0 && lastPoints[lastPoints.length - 1];
			var isLastPointTooClose = lastPoint
				? point.distanceTo(lastPoint) <= this.minDistance
				: false;
			var color = lastPointGroup.color;
			if (!lastPoint || !(lastPoint && isLastPointTooClose)) {
				var curve = this._addPoint(point);
				if (!lastPoint) {
					this._drawDot({ color: color, point: point });
				}
				else if (curve) {
					this._drawCurve({ color: color, curve: curve });
				}
				lastPoints.push({
					time: point.time,
					x: point.x,
					y: point.y
				});
			}
		};
		SignaturePad.prototype._strokeEnd = function (event) {
			this._strokeUpdate(event);
			if (typeof this.onEnd === 'function') {
				this.onEnd(event);
			}
		};
		SignaturePad.prototype._handlePointerEvents = function () {
			this._mouseButtonDown = false;
			this.canvas.addEventListener('pointerdown', this._handleMouseDown);
			this.canvas.addEventListener('pointermove', this._handleMouseMove);
			document.addEventListener('pointerup', this._handleMouseUp);
		};
		SignaturePad.prototype._handleMouseEvents = function () {
			this._mouseButtonDown = false;
			this.canvas.addEventListener('mousedown', this._handleMouseDown);
			this.canvas.addEventListener('mousemove', this._handleMouseMove);
			document.addEventListener('mouseup', this._handleMouseUp);
		};
		SignaturePad.prototype._handleTouchEvents = function () {
			this.canvas.addEventListener('touchstart', this._handleTouchStart);
			this.canvas.addEventListener('touchmove', this._handleTouchMove);
			this.canvas.addEventListener('touchend', this._handleTouchEnd);
		};
		SignaturePad.prototype._reset = function () {
			this._lastPoints = [];
			this._lastVelocity = 0;
			this._lastWidth = (this.minWidth + this.maxWidth) / 2;
			this._ctx.fillStyle = this.penColor;
		};
		SignaturePad.prototype._createPoint = function (x, y) {
			var rect = this.canvas.getBoundingClientRect();
			return new Point(x - rect.left, y - rect.top, new Date().getTime());
		};
		SignaturePad.prototype._addPoint = function (point) {
			var _lastPoints = this._lastPoints;
			_lastPoints.push(point);
			if (_lastPoints.length > 2) {
				if (_lastPoints.length === 3) {
					_lastPoints.unshift(_lastPoints[0]);
				}
				var widths = this._calculateCurveWidths(_lastPoints[1], _lastPoints[2]);
				var curve = Bezier.fromPoints(_lastPoints, widths);
				_lastPoints.shift();
				return curve;
			}
			return null;
		};
		SignaturePad.prototype._calculateCurveWidths = function (startPoint, endPoint) {
			var velocity = this.velocityFilterWeight * endPoint.velocityFrom(startPoint) +
				(1 - this.velocityFilterWeight) * this._lastVelocity;
			var newWidth = this._strokeWidth(velocity);
			var widths = {
				end: newWidth,
				start: this._lastWidth
			};
			this._lastVelocity = velocity;
			this._lastWidth = newWidth;
			return widths;
		};
		SignaturePad.prototype._strokeWidth = function (velocity) {
			return Math.max(this.maxWidth / (velocity + 1), this.minWidth);
		};
		SignaturePad.prototype._drawCurveSegment = function (x, y, width) {
			var ctx = this._ctx;
			ctx.moveTo(x, y);
			ctx.arc(x, y, width, 0, 2 * Math.PI, false);
			this._isEmpty = false;
		};
		SignaturePad.prototype._drawCurve = function (_a) {
			var color = _a.color, curve = _a.curve;
			var ctx = this._ctx;
			var widthDelta = curve.endWidth - curve.startWidth;
			var drawSteps = Math.floor(curve.length()) * 2;
			ctx.beginPath();
			ctx.fillStyle = color;
			for (var i = 0; i < drawSteps; i += 1) {
				var t = i / drawSteps;
				var tt = t * t;
				var ttt = tt * t;
				var u = 1 - t;
				var uu = u * u;
				var uuu = uu * u;
				var x = uuu * curve.startPoint.x;
				x += 3 * uu * t * curve.control1.x;
				x += 3 * u * tt * curve.control2.x;
				x += ttt * curve.endPoint.x;
				var y = uuu * curve.startPoint.y;
				y += 3 * uu * t * curve.control1.y;
				y += 3 * u * tt * curve.control2.y;
				y += ttt * curve.endPoint.y;
				var width = curve.startWidth + ttt * widthDelta;
				this._drawCurveSegment(x, y, width);
			}
			ctx.closePath();
			ctx.fill();
		};
		SignaturePad.prototype._drawDot = function (_a) {
			var color = _a.color, point = _a.point;
			var ctx = this._ctx;
			var width = typeof this.dotSize === 'function' ? this.dotSize() : this.dotSize;
			ctx.beginPath();
			this._drawCurveSegment(point.x, point.y, width);
			ctx.closePath();
			ctx.fillStyle = color;
			ctx.fill();
		};
		SignaturePad.prototype._fromData = function (pointGroups, drawCurve, drawDot) {
			for (var _i = 0, pointGroups_1 = pointGroups; _i < pointGroups_1.length; _i++) {
				var group = pointGroups_1[_i];
				var color = group.color, points = group.points;
				if (points.length > 1) {
					for (var j = 0; j < points.length; j += 1) {
						var basicPoint = points[j];
						var point = new Point(basicPoint.x, basicPoint.y, basicPoint.time);
						this.penColor = color;
						if (j === 0) {
							this._reset();
						}
						var curve = this._addPoint(point);
						if (curve) {
							drawCurve({ color: color, curve: curve });
						}
					}
				}
				else {
					this._reset();
					drawDot({
						color: color,
						point: points[0]
					});
				}
			}
		};
		SignaturePad.prototype._toSVG = function () {
			var _this = this;
			var pointGroups = this._data;
			var ratio = Math.max(window.devicePixelRatio || 1, 1);
			var minX = 0;
			var minY = 0;
			var maxX = this.canvas.width / ratio;
			var maxY = this.canvas.height / ratio;
			var svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
			svg.setAttribute('width', this.canvas.width.toString());
			svg.setAttribute('height', this.canvas.height.toString());
			this._fromData(pointGroups, function (_a) {
				var color = _a.color, curve = _a.curve;
				var path = document.createElement('path');
				if (!isNaN(curve.control1.x) &&
					!isNaN(curve.control1.y) &&
					!isNaN(curve.control2.x) &&
					!isNaN(curve.control2.y)) {
					var attr = "M " + curve.startPoint.x.toFixed(3) + "," + curve.startPoint.y.toFixed(3) + " " +
						("C " + curve.control1.x.toFixed(3) + "," + curve.control1.y.toFixed(3) + " ") +
						(curve.control2.x.toFixed(3) + "," + curve.control2.y.toFixed(3) + " ") +
						(curve.endPoint.x.toFixed(3) + "," + curve.endPoint.y.toFixed(3));
					path.setAttribute('d', attr);
					path.setAttribute('stroke-width', (curve.endWidth * 2.25).toFixed(3));
					path.setAttribute('stroke', color);
					path.setAttribute('fill', 'none');
					path.setAttribute('stroke-linecap', 'round');
					svg.appendChild(path);
				}
			}, function (_a) {
				var color = _a.color, point = _a.point;
				var circle = document.createElement('circle');
				var dotSize = typeof _this.dotSize === 'function' ? _this.dotSize() : _this.dotSize;
				circle.setAttribute('r', dotSize.toString());
				circle.setAttribute('cx', point.x.toString());
				circle.setAttribute('cy', point.y.toString());
				circle.setAttribute('fill', color);
				svg.appendChild(circle);
			});
			var prefix = 'data:image/svg+xml;base64,';
			var header = '<svg' +
				' xmlns="http://www.w3.org/2000/svg"' +
				' xmlns:xlink="http://www.w3.org/1999/xlink"' +
				(" viewBox=\"" + minX + " " + minY + " " + maxX + " " + maxY + "\"") +
				(" width=\"" + maxX + "\"") +
				(" height=\"" + maxY + "\"") +
				'>';
			var body = svg.innerHTML;
			if (body === undefined) {
				var dummy = document.createElement('dummy');
				var nodes = svg.childNodes;
				dummy.innerHTML = '';
				for (var i = 0; i < nodes.length; i += 1) {
					dummy.appendChild(nodes[i].cloneNode(true));
				}
				body = dummy.innerHTML;
			}
			var footer = '</svg>';
			var data = header + body + footer;
			return prefix + btoa(data);
		};
		return SignaturePad;
	}());

	return SignaturePad;

  })));
