pdf-lib
Version:
Create and modify PDF files with JavaScript
212 lines • 8.79 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.layoutSinglelineText = exports.layoutCombedText = exports.layoutMultilineText = void 0;
var errors_1 = require("../errors");
var alignment_1 = require("./alignment");
var utils_1 = require("../../utils");
var MIN_FONT_SIZE = 4;
var MAX_FONT_SIZE = 500;
var computeFontSize = function (lines, font, bounds, multiline) {
if (multiline === void 0) { multiline = false; }
var fontSize = MIN_FONT_SIZE;
while (fontSize < MAX_FONT_SIZE) {
var linesUsed = 0;
for (var lineIdx = 0, lineLen = lines.length; lineIdx < lineLen; lineIdx++) {
linesUsed += 1;
var line = lines[lineIdx];
var words = line.split(' ');
// Layout the words using the current `fontSize`, line wrapping
// whenever we reach the end of the current line.
var spaceInLineRemaining = bounds.width;
for (var idx = 0, len = words.length; idx < len; idx++) {
var isLastWord = idx === len - 1;
var word = isLastWord ? words[idx] : words[idx] + ' ';
var widthOfWord = font.widthOfTextAtSize(word, fontSize);
spaceInLineRemaining -= widthOfWord;
if (spaceInLineRemaining <= 0) {
linesUsed += 1;
spaceInLineRemaining = bounds.width - widthOfWord;
}
}
}
// Return if we exceeded the allowed width
if (!multiline && linesUsed > lines.length)
return fontSize - 1;
var height = font.heightAtSize(fontSize);
var lineHeight = height + height * 0.2;
var totalHeight = lineHeight * linesUsed;
// Return if we exceeded the allowed height
if (totalHeight > Math.abs(bounds.height))
return fontSize - 1;
fontSize += 1;
}
return fontSize;
};
var computeCombedFontSize = function (line, font, bounds, cellCount) {
var cellWidth = bounds.width / cellCount;
var cellHeight = bounds.height;
var fontSize = MIN_FONT_SIZE;
var chars = utils_1.charSplit(line);
while (fontSize < MAX_FONT_SIZE) {
for (var idx = 0, len = chars.length; idx < len; idx++) {
var c = chars[idx];
var tooLong = font.widthOfTextAtSize(c, fontSize) > cellWidth * 0.75;
if (tooLong)
return fontSize - 1;
}
var height = font.heightAtSize(fontSize, { descender: false });
if (height > cellHeight)
return fontSize - 1;
fontSize += 1;
}
return fontSize;
};
var lastIndexOfWhitespace = function (line) {
for (var idx = line.length; idx > 0; idx--) {
if (/\s/.test(line[idx]))
return idx;
}
return undefined;
};
var splitOutLines = function (input, maxWidth, font, fontSize) {
var _a;
var lastWhitespaceIdx = input.length;
while (lastWhitespaceIdx > 0) {
var line = input.substring(0, lastWhitespaceIdx);
var encoded = font.encodeText(line);
var width = font.widthOfTextAtSize(line, fontSize);
if (width < maxWidth) {
var remainder = input.substring(lastWhitespaceIdx) || undefined;
return { line: line, encoded: encoded, width: width, remainder: remainder };
}
lastWhitespaceIdx = (_a = lastIndexOfWhitespace(line)) !== null && _a !== void 0 ? _a : 0;
}
// We were unable to split the input enough to get a chunk that would fit
// within the specified `maxWidth` so we'll just return everything
return {
line: input,
encoded: font.encodeText(input),
width: font.widthOfTextAtSize(input, fontSize),
remainder: undefined,
};
};
exports.layoutMultilineText = function (text, _a) {
var alignment = _a.alignment, fontSize = _a.fontSize, font = _a.font, bounds = _a.bounds;
var lines = utils_1.lineSplit(utils_1.cleanText(text));
if (fontSize === undefined || fontSize === 0) {
fontSize = computeFontSize(lines, font, bounds, true);
}
var height = font.heightAtSize(fontSize);
var lineHeight = height + height * 0.2;
var textLines = [];
var minX = bounds.x;
var minY = bounds.y;
var maxX = bounds.x + bounds.width;
var maxY = bounds.y + bounds.height;
var y = bounds.y + bounds.height;
for (var idx = 0, len = lines.length; idx < len; idx++) {
var prevRemainder = lines[idx];
while (prevRemainder !== undefined) {
var _b = splitOutLines(prevRemainder, bounds.width, font, fontSize), line = _b.line, encoded = _b.encoded, width = _b.width, remainder = _b.remainder;
// prettier-ignore
var x = (alignment === alignment_1.TextAlignment.Left ? bounds.x
: alignment === alignment_1.TextAlignment.Center ? bounds.x + (bounds.width / 2) - (width / 2)
: alignment === alignment_1.TextAlignment.Right ? bounds.x + bounds.width - width
: bounds.x);
y -= lineHeight;
if (x < minX)
minX = x;
if (y < minY)
minY = y;
if (x + width > maxX)
maxX = x + width;
if (y + height > maxY)
maxY = y + height;
textLines.push({ text: line, encoded: encoded, width: width, height: height, x: x, y: y });
// Only trim lines that we had to split ourselves. So we won't trim lines
// that the user provided themselves with whitespace.
prevRemainder = remainder === null || remainder === void 0 ? void 0 : remainder.trim();
}
}
return {
fontSize: fontSize,
lineHeight: lineHeight,
lines: textLines,
bounds: {
x: minX,
y: minY,
width: maxX - minX,
height: maxY - minY,
},
};
};
exports.layoutCombedText = function (text, _a) {
var fontSize = _a.fontSize, font = _a.font, bounds = _a.bounds, cellCount = _a.cellCount;
var line = utils_1.mergeLines(utils_1.cleanText(text));
if (line.length > cellCount) {
throw new errors_1.CombedTextLayoutError(line.length, cellCount);
}
if (fontSize === undefined || fontSize === 0) {
fontSize = computeCombedFontSize(line, font, bounds, cellCount);
}
var cellWidth = bounds.width / cellCount;
var height = font.heightAtSize(fontSize, { descender: false });
var y = bounds.y + (bounds.height / 2 - height / 2);
var cells = [];
var minX = bounds.x;
var minY = bounds.y;
var maxX = bounds.x + bounds.width;
var maxY = bounds.y + bounds.height;
var cellOffset = 0;
var charOffset = 0;
while (cellOffset < cellCount) {
var _b = utils_1.charAtIndex(line, charOffset), char = _b[0], charLength = _b[1];
var encoded = font.encodeText(char);
var width = font.widthOfTextAtSize(char, fontSize);
var cellCenter = bounds.x + (cellWidth * cellOffset + cellWidth / 2);
var x = cellCenter - width / 2;
if (x < minX)
minX = x;
if (y < minY)
minY = y;
if (x + width > maxX)
maxX = x + width;
if (y + height > maxY)
maxY = y + height;
cells.push({ text: line, encoded: encoded, width: width, height: height, x: x, y: y });
cellOffset += 1;
charOffset += charLength;
}
return {
fontSize: fontSize,
cells: cells,
bounds: {
x: minX,
y: minY,
width: maxX - minX,
height: maxY - minY,
},
};
};
exports.layoutSinglelineText = function (text, _a) {
var alignment = _a.alignment, fontSize = _a.fontSize, font = _a.font, bounds = _a.bounds;
var line = utils_1.mergeLines(utils_1.cleanText(text));
if (fontSize === undefined || fontSize === 0) {
fontSize = computeFontSize([line], font, bounds);
}
var encoded = font.encodeText(line);
var width = font.widthOfTextAtSize(line, fontSize);
var height = font.heightAtSize(fontSize, { descender: false });
// prettier-ignore
var x = (alignment === alignment_1.TextAlignment.Left ? bounds.x
: alignment === alignment_1.TextAlignment.Center ? bounds.x + (bounds.width / 2) - (width / 2)
: alignment === alignment_1.TextAlignment.Right ? bounds.x + bounds.width - width
: bounds.x);
var y = bounds.y + (bounds.height / 2 - height / 2);
return {
fontSize: fontSize,
line: { text: line, encoded: encoded, width: width, height: height, x: x, y: y },
bounds: { x: x, y: y, width: width, height: height },
};
};
//# sourceMappingURL=layout.js.map