text: /*!
   * Signature Pad v4.0.0 | https://github.com/szimek/signature_pad
   * (c) 2022 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';
  
      class Point {
          constructor(x, y, pressure, time) {
              if (isNaN(x) || isNaN(y)) {
                  throw new Error(`Point is invalid: (${x}, ${y})`);
              }
              this.x = +x;
              this.y = +y;
              this.pressure = pressure || 0;
              this.time = time || Date.now();
          }
          distanceTo(start) {
              return Math.sqrt(Math.pow(this.x - start.x, 2) + Math.pow(this.y - start.y, 2));
          }
          equals(other) {
              return (this.x === other.x &&
                  this.y === other.y &&
                  this.pressure === other.pressure &&
                  this.time === other.time);
          }
          velocityFrom(start) {
              return this.time !== start.time
                  ? this.distanceTo(start) / (this.time - start.time)
                  : 0;
          }
      }
  
      class Bezier {
          constructor(startPoint, control2, control1, endPoint, startWidth, endWidth) {
              this.startPoint = startPoint;
              this.control2 = control2;
              this.control1 = control1;
              this.endPoint = endPoint;
              this.startWidth = startWidth;
              this.endWidth = endWidth;
          }
          static fromPoints(points, widths) {
              const c2 = this.calculateControlPoints(points[0], points[1], points[2]).c2;
              const c3 = this.calculateControlPoints(points[1], points[2], points[3]).c1;
              return new Bezier(points[1], c2, c3, points[2], widths.start, widths.end);
          }
          static calculateControlPoints(s1, s2, s3) {
              const dx1 = s1.x - s2.x;
              const dy1 = s1.y - s2.y;
              const dx2 = s2.x - s3.x;
              const dy2 = s2.y - s3.y;
              const m1 = { x: (s1.x + s2.x) / 2.0, y: (s1.y + s2.y) / 2.0 };
              const m2 = { x: (s2.x + s3.x) / 2.0, y: (s2.y + s3.y) / 2.0 };
              const l1 = Math.sqrt(dx1 * dx1 + dy1 * dy1);
              const l2 = Math.sqrt(dx2 * dx2 + dy2 * dy2);
              const dxm = m1.x - m2.x;
              const dym = m1.y - m2.y;
              const k = l2 / (l1 + l2);
              const cm = { x: m2.x + dxm * k, y: m2.y + dym * k };
              const tx = s2.x - cm.x;
              const ty = s2.y - cm.y;
              return {
                  c1: new Point(m1.x + tx, m1.y + ty),
                  c2: new Point(m2.x + tx, m2.y + ty),
              };
          }
          length() {
              const steps = 10;
              let length = 0;
              let px;
              let py;
              for (let i = 0; i <= steps; i += 1) {
                  const t = i / steps;
                  const cx = this.point(t, this.startPoint.x, this.control1.x, this.control2.x, this.endPoint.x);
                  const cy = this.point(t, this.startPoint.y, this.control1.y, this.control2.y, this.endPoint.y);
                  if (i > 0) {
                      const xdiff = cx - px;
                      const ydiff = cy - py;
                      length += Math.sqrt(xdiff * xdiff + ydiff * ydiff);
                  }
                  px = cx;
                  py = cy;
              }
              return length;
          }
          point(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);
          }
      }
  
      class SignatureEventTarget {
          constructor() {
              try {
                  this._et = new EventTarget();
              }
              catch (error) {
                  this._et = document;
              }
          }
          addEventListener(type, listener, options) {
              this._et.addEventListener(type, listener, options);
          }
          dispatchEvent(event) {
              return this._et.dispatchEvent(event);
          }
          removeEventListener(type, callback, options) {
              this._et.removeEventListener(type, callback, options);
          }
      }
  
      function throttle(fn, wait = 250) {
          let previous = 0;
          let timeout = null;
          let result;
          let storedContext;
          let storedArgs;
          const later = () => {
              previous = Date.now();
              timeout = null;
              result = fn.apply(storedContext, storedArgs);
              if (!timeout) {
                  storedContext = null;
                  storedArgs = [];
              }
          };
          return function wrapper(...args) {
              const now = Date.now();
              const 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;
          };
      }
  
      class SignaturePad extends SignatureEventTarget {
          constructor(canvas, options = {}) {
              super();
              this.canvas = canvas;
              this._handleMouseDown = (event) => {
                  if (event.buttons === 1) {
                      this._drawningStroke = true;
                      this._strokeBegin(event);
                  }
              };
              this._handleMouseMove = (event) => {
                  if (this._drawningStroke) {
                      this._strokeMoveUpdate(event);
                  }
              };
              this._handleMouseUp = (event) => {
                  if (event.buttons === 1 && this._drawningStroke) {
                      this._drawningStroke = false;
                      this._strokeEnd(event);
                  }
              };
              this._handleTouchStart = (event) => {
                  event.preventDefault();
                  if (event.targetTouches.length === 1) {
                      const touch = event.changedTouches[0];
                      this._strokeBegin(touch);
                  }
              };
              this._handleTouchMove = (event) => {
                  event.preventDefault();
                  const touch = event.targetTouches[0];
                  this._strokeMoveUpdate(touch);
              };
              this._handleTouchEnd = (event) => {
                  const wasCanvasTouched = event.target === this.canvas;
                  if (wasCanvasTouched) {
                      event.preventDefault();
                      const touch = event.changedTouches[0];
                      this._strokeEnd(touch);
                  }
              };
              this._handlePointerStart = (event) => {
                  this._drawningStroke = true;
                  event.preventDefault();
                  this._strokeBegin(event);
              };
              this._handlePointerMove = (event) => {
                  if (this._drawningStroke) {
                      event.preventDefault();
                      this._strokeMoveUpdate(event);
                  }
              };
              this._handlePointerEnd = (event) => {
                  this._drawningStroke = false;
                  const wasCanvasTouched = event.target === this.canvas;
                  if (wasCanvasTouched) {
                      event.preventDefault();
                      this._strokeEnd(event);
                  }
              };
              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 || 0;
              this.penColor = options.penColor || 'black';
              this.backgroundColor = options.backgroundColor || 'rgba(0,0,0,0)';
              this._strokeMoveUpdate = this.throttle
                  ? throttle(SignaturePad.prototype._strokeUpdate, this.throttle)
                  : SignaturePad.prototype._strokeUpdate;
              this._ctx = canvas.getContext('2d');
              this.clear();
              this.on();
          }
          clear() {
              const { _ctx: ctx, canvas } = this;
              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;
          }
          fromDataURL(dataUrl, options = {}) {
              return new Promise((resolve, reject) => {
                  const image = new Image();
                  const ratio = options.ratio || window.devicePixelRatio || 1;
                  const width = options.width || this.canvas.width / ratio;
                  const height = options.height || this.canvas.height / ratio;
                  const xOffset = options.xOffset || 0;
                  const yOffset = options.yOffset || 0;
                  this._reset();
                  image.onload = () => {
                      this._ctx.drawImage(image, xOffset, yOffset, width, height);
                      resolve();
                  };
                  image.onerror = (error) => {
                      reject(error);
                  };
                  image.crossOrigin = 'anonymous';
                  image.src = dataUrl;
                  this._isEmpty = false;
              });
          }
          toDataURL(type = 'image/png', encoderOptions) {
              switch (type) {
                  case 'image/svg+xml':
                      return this._toSVG();
                  default:
                      return this.canvas.toDataURL(type, encoderOptions);
              }
          }
          on() {
              this.canvas.style.touchAction = 'none';
              this.canvas.style.msTouchAction = 'none';
              const isIOS = /Macintosh/.test(navigator.userAgent) && 'ontouchstart' in document;
              if (window.PointerEvent && !isIOS) {
                  this._handlePointerEvents();
              }
              else {
                  this._handleMouseEvents();
                  if ('ontouchstart' in window) {
                      this._handleTouchEvents();
                  }
              }
          }
          off() {
              this.canvas.style.touchAction = 'auto';
              this.canvas.style.msTouchAction = 'auto';
              this.canvas.removeEventListener('pointerdown', this._handlePointerStart);
              this.canvas.removeEventListener('pointermove', this._handlePointerMove);
              document.removeEventListener('pointerup', this._handlePointerEnd);
              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);
          }
          isEmpty() {
              return this._isEmpty;
          }
          fromData(pointGroups, { clear = true } = {}) {
              if (clear) {
                  this.clear();
              }
              this._fromData(pointGroups, this._drawCurve.bind(this), this._drawDot.bind(this));
              this._data = clear ? pointGroups : this._data.concat(pointGroups);
          }
          toData() {
              return this._data;
          }
          _strokeBegin(event) {
              this.dispatchEvent(new CustomEvent('beginStroke', { detail: event }));
              const newPointGroup = {
                  dotSize: this.dotSize,
                  minWidth: this.minWidth,
                  maxWidth: this.maxWidth,
                  penColor: this.penColor,
                  points: [],
              };
              this._data.push(newPointGroup);
              this._reset();
              this._strokeUpdate(event);
          }
          _strokeUpdate(event) {
              if (this._data.length === 0) {
                  this._strokeBegin(event);
                  return;
              }
              this.dispatchEvent(new CustomEvent('beforeUpdateStroke', { detail: event }));
              const x = event.clientX;
              const y = event.clientY;
              const pressure = event.pressure !== undefined
                  ? event.pressure
                  : event.force !== undefined
                      ? event.force
                      : 0;
              const point = this._createPoint(x, y, pressure);
              const lastPointGroup = this._data[this._data.length - 1];
              const lastPoints = lastPointGroup.points;
              const lastPoint = lastPoints.length > 0 && lastPoints[lastPoints.length - 1];
              const isLastPointTooClose = lastPoint
                  ? point.distanceTo(lastPoint) <= this.minDistance
                  : false;
              const { penColor, dotSize, minWidth, maxWidth } = lastPointGroup;
              if (!lastPoint || !(lastPoint && isLastPointTooClose)) {
                  const curve = this._addPoint(point);
                  if (!lastPoint) {
                      this._drawDot(point, {
                          penColor,
                          dotSize,
                          minWidth,
                          maxWidth,
                      });
                  }
                  else if (curve) {
                      this._drawCurve(curve, {
                          penColor,
                          dotSize,
                          minWidth,
                          maxWidth,
                      });
                  }
                  lastPoints.push({
                      time: point.time,
                      x: point.x,
                      y: point.y,
                      pressure: point.pressure,
                  });
              }
              this.dispatchEvent(new CustomEvent('afterUpdateStroke', { detail: event }));
          }
          _strokeEnd(event) {
              this._strokeUpdate(event);
              this.dispatchEvent(new CustomEvent('endStroke', { detail: event }));
          }
          _handlePointerEvents() {
              this._drawningStroke = false;
              this.canvas.addEventListener('pointerdown', this._handlePointerStart);
              this.canvas.addEventListener('pointermove', this._handlePointerMove);
              document.addEventListener('pointerup', this._handlePointerEnd);
          }
          _handleMouseEvents() {
              this._drawningStroke = false;
              this.canvas.addEventListener('mousedown', this._handleMouseDown);
              this.canvas.addEventListener('mousemove', this._handleMouseMove);
              document.addEventListener('mouseup', this._handleMouseUp);
          }
          _handleTouchEvents() {
              this.canvas.addEventListener('touchstart', this._handleTouchStart);
              this.canvas.addEventListener('touchmove', this._handleTouchMove);
              this.canvas.addEventListener('touchend', this._handleTouchEnd);
          }
          _reset() {
              this._lastPoints = [];
              this._lastVelocity = 0;
              this._lastWidth = (this.minWidth + this.maxWidth) / 2;
              this._ctx.fillStyle = this.penColor;
          }
          _createPoint(x, y, pressure) {
              const rect = this.canvas.getBoundingClientRect();
              return new Point(x - rect.left, y - rect.top, pressure, new Date().getTime());
          }
          _addPoint(point) {
              const { _lastPoints } = this;
              _lastPoints.push(point);
              if (_lastPoints.length > 2) {
                  if (_lastPoints.length === 3) {
                      _lastPoints.unshift(_lastPoints[0]);
                  }
                  const widths = this._calculateCurveWidths(_lastPoints[1], _lastPoints[2]);
                  const curve = Bezier.fromPoints(_lastPoints, widths);
                  _lastPoints.shift();
                  return curve;
              }
              return null;
          }
          _calculateCurveWidths(startPoint, endPoint) {
              const velocity = this.velocityFilterWeight * endPoint.velocityFrom(startPoint) +
                  (1 - this.velocityFilterWeight) * this._lastVelocity;
              const newWidth = this._strokeWidth(velocity);
              const widths = {
                  end: newWidth,
                  start: this._lastWidth,
              };
              this._lastVelocity = velocity;
              this._lastWidth = newWidth;
              return widths;
          }
          _strokeWidth(velocity) {
              return Math.max(this.maxWidth / (velocity + 1), this.minWidth);
          }
          _drawCurveSegment(x, y, width) {
              const ctx = this._ctx;
              ctx.moveTo(x, y);
              ctx.arc(x, y, width, 0, 2 * Math.PI, false);
              this._isEmpty = false;
          }
          _drawCurve(curve, options) {
              const ctx = this._ctx;
              const widthDelta = curve.endWidth - curve.startWidth;
              const drawSteps = Math.ceil(curve.length()) * 2;
              ctx.beginPath();
              ctx.fillStyle = options.penColor;
              for (let i = 0; i < drawSteps; i += 1) {
                  const t = i / drawSteps;
                  const tt = t * t;
                  const ttt = tt * t;
                  const u = 1 - t;
                  const uu = u * u;
                  const uuu = uu * u;
                  let x = uuu * curve.startPoint.x;
                  x += 3 * uu * t * curve.control1.x;
                  x += 3 * u * tt * curve.control2.x;
                  x += ttt * curve.endPoint.x;
                  let y = uuu * curve.startPoint.y;
                  y += 3 * uu * t * curve.control1.y;
                  y += 3 * u * tt * curve.control2.y;
                  y += ttt * curve.endPoint.y;
                  const width = Math.min(curve.startWidth + ttt * widthDelta, options.maxWidth);
                  this._drawCurveSegment(x, y, width);
              }
              ctx.closePath();
              ctx.fill();
          }
          _drawDot(point, options) {
              const ctx = this._ctx;
              const width = options.dotSize > 0
                  ? options.dotSize
                  : (options.minWidth + options.maxWidth) / 2;
              ctx.beginPath();
              this._drawCurveSegment(point.x, point.y, width);
              ctx.closePath();
              ctx.fillStyle = options.penColor;
              ctx.fill();
          }
          _fromData(pointGroups, drawCurve, drawDot) {
              for (const group of pointGroups) {
                  const { penColor, dotSize, minWidth, maxWidth, points } = group;
                  if (points.length > 1) {
                      for (let j = 0; j < points.length; j += 1) {
                          const basicPoint = points[j];
                          const point = new Point(basicPoint.x, basicPoint.y, basicPoint.pressure, basicPoint.time);
                          this.penColor = penColor;
                          if (j === 0) {
                              this._reset();
                          }
                          const curve = this._addPoint(point);
                          if (curve) {
                              drawCurve(curve, {
                                  penColor,
                                  dotSize,
                                  minWidth,
                                  maxWidth,
                              });
                          }
                      }
                  }
                  else {
                      this._reset();
                      drawDot(points[0], {
                          penColor,
                          dotSize,
                          minWidth,
                          maxWidth,
                      });
                  }
              }
          }
          _toSVG() {
              const pointGroups = this._data;
              const ratio = Math.max(window.devicePixelRatio || 1, 1);
              const minX = 0;
              const minY = 0;
              const maxX = this.canvas.width / ratio;
              const maxY = this.canvas.height / ratio;
              const 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, (curve, { penColor }) => {
                  const path = document.createElement('path');
                  if (!isNaN(curve.control1.x) &&
                      !isNaN(curve.control1.y) &&
                      !isNaN(curve.control2.x) &&
                      !isNaN(curve.control2.y)) {
                      const 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', penColor);
                      path.setAttribute('fill', 'none');
                      path.setAttribute('stroke-linecap', 'round');
                      svg.appendChild(path);
                  }
              }, (point, { penColor, dotSize, minWidth, maxWidth }) => {
                  const circle = document.createElement('circle');
                  const size = dotSize > 0 ? dotSize : (minWidth + maxWidth) / 2;
                  circle.setAttribute('r', size.toString());
                  circle.setAttribute('cx', point.x.toString());
                  circle.setAttribute('cy', point.y.toString());
                  circle.setAttribute('fill', penColor);
                  svg.appendChild(circle);
              });
              const prefix = 'data:image/svg+xml;base64,';
              const header = '<svg' +
                  ' xmlns="http://www.w3.org/2000/svg"' +
                  ' xmlns:xlink="http://www.w3.org/1999/xlink"' +
                  ` viewBox="${minX} ${minY} ${this.canvas.width} ${this.canvas.height}"` +
                  ` width="${maxX}"` +
                  ` height="${maxY}"` +
                  '>';
              let body = svg.innerHTML;
              if (body === undefined) {
                  const dummy = document.createElement('dummy');
                  const nodes = svg.childNodes;
                  dummy.innerHTML = '';
                  for (let i = 0; i < nodes.length; i += 1) {
                      dummy.appendChild(nodes[i].cloneNode(true));
                  }
                  body = dummy.innerHTML;
              }
              const footer = '</svg>';
              const data = header + body + footer;
              return prefix + btoa(data);
          }
      }
  
      return SignaturePad;
  
  }));
  //# sourceMappingURL=signature_pad.umd.js.map
  