pdfjs-dist/lib/display/display_utils.js

/**
 * @licstart The following is the entire license notice for the
 * JavaScript code in this page
 *
 * Copyright 2022 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * JavaScript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.StatTimer = exports.RenderingCancelledException = exports.PixelsPerInch = exports.PageViewport = exports.PDFDateString = exports.DOMStandardFontDataFactory = exports.DOMSVGFactory = exports.DOMCanvasFactory = exports.DOMCMapReaderFactory = exports.AnnotationPrefix = void 0;
exports.deprecated = deprecated;
exports.getColorValues = getColorValues;
exports.getCurrentTransform = getCurrentTransform;
exports.getCurrentTransformInverse = getCurrentTransformInverse;
exports.getFilenameFromUrl = getFilenameFromUrl;
exports.getPdfFilenameFromUrl = getPdfFilenameFromUrl;
exports.getRGB = getRGB;
exports.getXfaPageViewport = getXfaPageViewport;
exports.isDataScheme = isDataScheme;
exports.isPdfFile = isPdfFile;
exports.isValidFetchUrl = isValidFetchUrl;
exports.loadScript = loadScript;

var _base_factory = require("./base_factory.js");

var _util = require("../shared/util.js");

const SVG_NS = "http://www.w3.org/2000/svg";
const AnnotationPrefix = "pdfjs_internal_id_";
exports.AnnotationPrefix = AnnotationPrefix;

class PixelsPerInch {
  static CSS = 96.0;
  static PDF = 72.0;
  static PDF_TO_CSS_UNITS = this.CSS / this.PDF;
}

exports.PixelsPerInch = PixelsPerInch;

class DOMCanvasFactory extends _base_factory.BaseCanvasFactory {
  constructor({
    ownerDocument = globalThis.document
  } = {}) {
    super();
    this._document = ownerDocument;
  }

  _createCanvas(width, height) {
    const canvas = this._document.createElement("canvas");

    canvas.width = width;
    canvas.height = height;
    return canvas;
  }

}

exports.DOMCanvasFactory = DOMCanvasFactory;

async function fetchData(url, asTypedArray = false) {
  if (isValidFetchUrl(url, document.baseURI)) {
    const response = await fetch(url);

    if (!response.ok) {
      throw new Error(response.statusText);
    }

    return asTypedArray ? new Uint8Array(await response.arrayBuffer()) : (0, _util.stringToBytes)(await response.text());
  }

  return new Promise((resolve, reject) => {
    const request = new XMLHttpRequest();
    request.open("GET", url, true);

    if (asTypedArray) {
      request.responseType = "arraybuffer";
    }

    request.onreadystatechange = () => {
      if (request.readyState !== XMLHttpRequest.DONE) {
        return;
      }

      if (request.status === 200 || request.status === 0) {
        let data;

        if (asTypedArray && request.response) {
          data = new Uint8Array(request.response);
        } else if (!asTypedArray && request.responseText) {
          data = (0, _util.stringToBytes)(request.responseText);
        }

        if (data) {
          resolve(data);
          return;
        }
      }

      reject(new Error(request.statusText));
    };

    request.send(null);
  });
}

class DOMCMapReaderFactory extends _base_factory.BaseCMapReaderFactory {
  _fetchData(url, compressionType) {
    return fetchData(url, this.isCompressed).then(data => {
      return {
        cMapData: data,
        compressionType
      };
    });
  }

}

exports.DOMCMapReaderFactory = DOMCMapReaderFactory;

class DOMStandardFontDataFactory extends _base_factory.BaseStandardFontDataFactory {
  _fetchData(url) {
    return fetchData(url, true);
  }

}

exports.DOMStandardFontDataFactory = DOMStandardFontDataFactory;

class DOMSVGFactory extends _base_factory.BaseSVGFactory {
  _createSVG(type) {
    return document.createElementNS(SVG_NS, type);
  }

}

exports.DOMSVGFactory = DOMSVGFactory;

class PageViewport {
  constructor({
    viewBox,
    scale,
    rotation,
    offsetX = 0,
    offsetY = 0,
    dontFlip = false
  }) {
    this.viewBox = viewBox;
    this.scale = scale;
    this.rotation = rotation;
    this.offsetX = offsetX;
    this.offsetY = offsetY;
    const centerX = (viewBox[2] + viewBox[0]) / 2;
    const centerY = (viewBox[3] + viewBox[1]) / 2;
    let rotateA, rotateB, rotateC, rotateD;
    rotation %= 360;

    if (rotation < 0) {
      rotation += 360;
    }

    switch (rotation) {
      case 180:
        rotateA = -1;
        rotateB = 0;
        rotateC = 0;
        rotateD = 1;
        break;

      case 90:
        rotateA = 0;
        rotateB = 1;
        rotateC = 1;
        rotateD = 0;
        break;

      case 270:
        rotateA = 0;
        rotateB = -1;
        rotateC = -1;
        rotateD = 0;
        break;

      case 0:
        rotateA = 1;
        rotateB = 0;
        rotateC = 0;
        rotateD = -1;
        break;

      default:
        throw new Error("PageViewport: Invalid rotation, must be a multiple of 90 degrees.");
    }

    if (dontFlip) {
      rotateC = -rotateC;
      rotateD = -rotateD;
    }

    let offsetCanvasX, offsetCanvasY;
    let width, height;

    if (rotateA === 0) {
      offsetCanvasX = Math.abs(centerY - viewBox[1]) * scale + offsetX;
      offsetCanvasY = Math.abs(centerX - viewBox[0]) * scale + offsetY;
      width = Math.abs(viewBox[3] - viewBox[1]) * scale;
      height = Math.abs(viewBox[2] - viewBox[0]) * scale;
    } else {
      offsetCanvasX = Math.abs(centerX - viewBox[0]) * scale + offsetX;
      offsetCanvasY = Math.abs(centerY - viewBox[1]) * scale + offsetY;
      width = Math.abs(viewBox[2] - viewBox[0]) * scale;
      height = Math.abs(viewBox[3] - viewBox[1]) * scale;
    }

    this.transform = [rotateA * scale, rotateB * scale, rotateC * scale, rotateD * scale, offsetCanvasX - rotateA * scale * centerX - rotateC * scale * centerY, offsetCanvasY - rotateB * scale * centerX - rotateD * scale * centerY];
    this.width = width;
    this.height = height;
  }

  clone({
    scale = this.scale,
    rotation = this.rotation,
    offsetX = this.offsetX,
    offsetY = this.offsetY,
    dontFlip = false
  } = {}) {
    return new PageViewport({
      viewBox: this.viewBox.slice(),
      scale,
      rotation,
      offsetX,
      offsetY,
      dontFlip
    });
  }

  convertToViewportPoint(x, y) {
    return _util.Util.applyTransform([x, y], this.transform);
  }

  convertToViewportRectangle(rect) {
    const topLeft = _util.Util.applyTransform([rect[0], rect[1]], this.transform);

    const bottomRight = _util.Util.applyTransform([rect[2], rect[3]], this.transform);

    return [topLeft[0], topLeft[1], bottomRight[0], bottomRight[1]];
  }

  convertToPdfPoint(x, y) {
    return _util.Util.applyInverseTransform([x, y], this.transform);
  }

}

exports.PageViewport = PageViewport;

class RenderingCancelledException extends _util.BaseException {
  constructor(msg, type) {
    super(msg, "RenderingCancelledException");
    this.type = type;
  }

}

exports.RenderingCancelledException = RenderingCancelledException;

function isDataScheme(url) {
  const ii = url.length;
  let i = 0;

  while (i < ii && url[i].trim() === "") {
    i++;
  }

  return url.substring(i, i + 5).toLowerCase() === "data:";
}

function isPdfFile(filename) {
  return typeof filename === "string" && /\.pdf$/i.test(filename);
}

function getFilenameFromUrl(url) {
  const anchor = url.indexOf("#");
  const query = url.indexOf("?");
  const end = Math.min(anchor > 0 ? anchor : url.length, query > 0 ? query : url.length);
  return url.substring(url.lastIndexOf("/", end) + 1, end);
}

function getPdfFilenameFromUrl(url, defaultFilename = "document.pdf") {
  if (typeof url !== "string") {
    return defaultFilename;
  }

  if (isDataScheme(url)) {
    (0, _util.warn)('getPdfFilenameFromUrl: ignore "data:"-URL for performance reasons.');
    return defaultFilename;
  }

  const reURI = /^(?:(?:[^:]+:)?\/\/[^/]+)?([^?#]*)(\?[^#]*)?(#.*)?$/;
  const reFilename = /[^/?#=]+\.pdf\b(?!.*\.pdf\b)/i;
  const splitURI = reURI.exec(url);
  let suggestedFilename = reFilename.exec(splitURI[1]) || reFilename.exec(splitURI[2]) || reFilename.exec(splitURI[3]);

  if (suggestedFilename) {
    suggestedFilename = suggestedFilename[0];

    if (suggestedFilename.includes("%")) {
      try {
        suggestedFilename = reFilename.exec(decodeURIComponent(suggestedFilename))[0];
      } catch (ex) {}
    }
  }

  return suggestedFilename || defaultFilename;
}

class StatTimer {
  constructor() {
    this.started = Object.create(null);
    this.times = [];
  }

  time(name) {
    if (name in this.started) {
      (0, _util.warn)(`Timer is already running for ${name}`);
    }

    this.started[name] = Date.now();
  }

  timeEnd(name) {
    if (!(name in this.started)) {
      (0, _util.warn)(`Timer has not been started for ${name}`);
    }

    this.times.push({
      name,
      start: this.started[name],
      end: Date.now()
    });
    delete this.started[name];
  }

  toString() {
    const outBuf = [];
    let longest = 0;

    for (const time of this.times) {
      const name = time.name;

      if (name.length > longest) {
        longest = name.length;
      }
    }

    for (const time of this.times) {
      const duration = time.end - time.start;
      outBuf.push(`${time.name.padEnd(longest)} ${duration}ms\n`);
    }

    return outBuf.join("");
  }

}

exports.StatTimer = StatTimer;

function isValidFetchUrl(url, baseUrl) {
  try {
    const {
      protocol
    } = baseUrl ? new URL(url, baseUrl) : new URL(url);
    return protocol === "http:" || protocol === "https:";
  } catch (ex) {
    return false;
  }
}

function loadScript(src, removeScriptElement = false) {
  return new Promise((resolve, reject) => {
    const script = document.createElement("script");
    script.src = src;

    script.onload = function (evt) {
      if (removeScriptElement) {
        script.remove();
      }

      resolve(evt);
    };

    script.onerror = function () {
      reject(new Error(`Cannot load script at: ${script.src}`));
    };

    (document.head || document.documentElement).append(script);
  });
}

function deprecated(details) {
  console.log("Deprecated API usage: " + details);
}

let pdfDateStringRegex;

class PDFDateString {
  static toDateObject(input) {
    if (!input || typeof input !== "string") {
      return null;
    }

    if (!pdfDateStringRegex) {
      pdfDateStringRegex = new RegExp("^D:" + "(\\d{4})" + "(\\d{2})?" + "(\\d{2})?" + "(\\d{2})?" + "(\\d{2})?" + "(\\d{2})?" + "([Z|+|-])?" + "(\\d{2})?" + "'?" + "(\\d{2})?" + "'?");
    }

    const matches = pdfDateStringRegex.exec(input);

    if (!matches) {
      return null;
    }

    const year = parseInt(matches[1], 10);
    let month = parseInt(matches[2], 10);
    month = month >= 1 && month <= 12 ? month - 1 : 0;
    let day = parseInt(matches[3], 10);
    day = day >= 1 && day <= 31 ? day : 1;
    let hour = parseInt(matches[4], 10);
    hour = hour >= 0 && hour <= 23 ? hour : 0;
    let minute = parseInt(matches[5], 10);
    minute = minute >= 0 && minute <= 59 ? minute : 0;
    let second = parseInt(matches[6], 10);
    second = second >= 0 && second <= 59 ? second : 0;
    const universalTimeRelation = matches[7] || "Z";
    let offsetHour = parseInt(matches[8], 10);
    offsetHour = offsetHour >= 0 && offsetHour <= 23 ? offsetHour : 0;
    let offsetMinute = parseInt(matches[9], 10) || 0;
    offsetMinute = offsetMinute >= 0 && offsetMinute <= 59 ? offsetMinute : 0;

    if (universalTimeRelation === "-") {
      hour += offsetHour;
      minute += offsetMinute;
    } else if (universalTimeRelation === "+") {
      hour -= offsetHour;
      minute -= offsetMinute;
    }

    return new Date(Date.UTC(year, month, day, hour, minute, second));
  }

}

exports.PDFDateString = PDFDateString;

function getXfaPageViewport(xfaPage, {
  scale = 1,
  rotation = 0
}) {
  const {
    width,
    height
  } = xfaPage.attributes.style;
  const viewBox = [0, 0, parseInt(width), parseInt(height)];
  return new PageViewport({
    viewBox,
    scale,
    rotation
  });
}

function getRGB(color) {
  if (color.startsWith("#")) {
    const colorRGB = parseInt(color.slice(1), 16);
    return [(colorRGB & 0xff0000) >> 16, (colorRGB & 0x00ff00) >> 8, colorRGB & 0x0000ff];
  }

  if (color.startsWith("rgb(")) {
    return color.slice(4, -1).split(",").map(x => parseInt(x));
  }

  if (color.startsWith("rgba(")) {
    return color.slice(5, -1).split(",").map(x => parseInt(x)).slice(0, 3);
  }

  (0, _util.warn)(`Not a valid color format: "${color}"`);
  return [0, 0, 0];
}

function getColorValues(colors) {
  const span = document.createElement("span");
  span.style.visibility = "hidden";
  document.body.append(span);

  for (const name of colors.keys()) {
    span.style.color = name;
    const computedColor = window.getComputedStyle(span).color;
    colors.set(name, getRGB(computedColor));
  }

  span.remove();
}

function getCurrentTransform(ctx) {
  const {
    a,
    b,
    c,
    d,
    e,
    f
  } = ctx.getTransform();
  return [a, b, c, d, e, f];
}

function getCurrentTransformInverse(ctx) {
  const {
    a,
    b,
    c,
    d,
    e,
    f
  } = ctx.getTransform().invertSelf();
  return [a, b, c, d, e, f];
}