/*!
 * Signature Pad v3.0.0-beta.4 | https://github.com/szimek/signature_pad
 * (c) 2020 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 = typeof globalThis !== 'undefined' ? globalThis : global || self, 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) {
            var _this = this;
            if (options === void 0) { options = {}; }
            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);
            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._strokeMoveUpdate = this.throttle
                ? throttle(SignaturePad.prototype._strokeUpdate, this.throttle)
                : SignaturePad.prototype._strokeUpdate;
            this._ctx = canvas.getContext('2d');
            this.clear();
            this.on();
        }
        SignaturePad.prototype.clear = function () {
            var _a = this, ctx = _a._ctx, canvas = _a.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) {
            if (this._data.length === 0) {
                this._strokeBegin(event);
                return;
            }
            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 = Math.min(curve.startWidth + ttt * widthDelta, this.maxWidth);
                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;

})));
//# sourceMappingURL=signature_pad.umd.js.map
