pdf-lib/es/core/embedders/CMap.js

Create and modify PDF files with JavaScript

import { toHexString, toHexStringOfMinLength } from "../../utils";
import { hasSurrogates, highSurrogate, isWithinBMP, lowSurrogate, } from "../../utils/unicode";
/** `glyphs` should be an array of unique glyphs sorted by their ID */
export var createCmap = function (glyphs, glyphId) {
    var bfRanges = [];
    var first = glyphId(glyphs[0]);
    var mappings = [];
    for (var idx = 0, len = glyphs.length; idx < len; idx++) {
        var currGlyph = glyphs[idx];
        var nextGlyph = glyphs[idx + 1];
        var currGlyphId = glyphId(currGlyph);
        var nextGlyphId = glyphId(nextGlyph);
        var codePoints = currGlyph.codePoints;
        mappings.push(cmapHexFormat.apply(void 0, codePoints.map(cmapCodePointFormat)));
        if (idx !== 0 && nextGlyphId - currGlyphId !== 1) {
            var last = currGlyphId;
            var delimiters = [
                cmapHexFormat(cmapHexString(first)),
                cmapHexFormat(cmapHexString(last)),
            ];
            bfRanges.push([delimiters, mappings]);
            first = nextGlyphId;
            mappings = [];
        }
    }
    return fillCmapTemplate(bfRanges);
};
/* =============================== Templates ================================ */
// prettier-ignore
var fillBfrangeTemplate = function (_a) {
    var _b = _a[0], start = _b[0], end = _b[1], mappings = _a[1];
    return ("\n" + mappings.length + " beginbfrange\n" + start + " " + end + " [" + mappings.join(' ') + "]\nendbfrange\n").trim();
};
// prettier-ignore
var fillCmapTemplate = function (bfRanges) { return ("\n/CIDInit /ProcSet findresource begin\n12 dict begin\nbegincmap\n/CIDSystemInfo <<\n  /Registry (Adobe)\n  /Ordering (UCS)\n  /Supplement 0\n>> def\n/CMapName /Adobe-Identity-UCS def\n/CMapType 2 def\n1 begincodespacerange\n<0000><ffff>\nendcodespacerange\n" + bfRanges.map(fillBfrangeTemplate).join('\n') + "\nendcmap\nCMapName currentdict /CMap defineresource pop\nend\nend\n").trim(); };
/* =============================== Utilities ================================ */
var cmapHexFormat = function () {
    var values = [];
    for (var _i = 0; _i < arguments.length; _i++) {
        values[_i] = arguments[_i];
    }
    return "<" + values.join('') + ">";
};
var cmapHexString = function (value) { return toHexStringOfMinLength(value, 4); };
var cmapCodePointFormat = function (codePoint) {
    if (isWithinBMP(codePoint))
        return cmapHexString(codePoint);
    if (hasSurrogates(codePoint)) {
        var hs = highSurrogate(codePoint);
        var ls = lowSurrogate(codePoint);
        return "" + cmapHexString(hs) + cmapHexString(ls);
    }
    var hex = toHexString(codePoint);
    var msg = "0x" + hex + " is not a valid UTF-8 or UTF-16 codepoint.";
    throw new Error(msg);
};
//# sourceMappingURL=CMap.js.map