import type PDFKit from 'pdfkit';
import { WRAP_EPSILON } from '../constants.ts';
import { measureEmoji, renderEmojiToBuffer, splitTextAndEmoji } from './emoji-renderer.ts';
import { hasEmoji } from './fonts.ts';
/**
* PDFKit text rendering options
*/
export interface PDFTextOptions {
x?: number;
y?: number;
align?: 'left' | 'center' | 'right' | 'justify';
indent?: number;
lineGap?: number;
paragraphGap?: number;
width?: number;
underline?: boolean;
strike?: boolean;
oblique?: boolean | number;
link?: string;
characterSpacing?: number;
wordSpacing?: number;
continued?: boolean;
lineBreak?: boolean;
moveDown?: number;
}
/**
* Render text with inline emoji support
*
* If emoji font is available and text contains emoji, renders emoji as inline images.
* Otherwise, renders text normally using PDFKit.
*
* Supports both single-line and multi-line/wrapped text with emoji.
*
* @param doc - PDFKit document
* @param text - Text to render (may contain emoji)
* @param fontSize - Font size in points
* @param fontName - Font name to use for text
* @param emojiAvailable - Whether emoji font is available
* @param options - Additional PDFKit text options
*/
export function renderTextWithEmoji(doc: PDFKit.PDFDocument, text: string, fontSize: number, fontName: string, emojiAvailable: boolean, options: PDFTextOptions = {}): void {
if (!emojiAvailable || !hasEmoji(text)) {
// No emoji support or no emoji in text - render normally
doc.fontSize(fontSize).font(fontName);
// PDFKit requires three-argument form for proper positioning with width
if (options.x !== undefined || options.y !== undefined) {
const textOptions = { ...options };
delete textOptions.x;
delete textOptions.y;
doc.text(text, options.x, options.y, textOptions);
} else {
doc.text(text, options);
}
return;
}
// Setup font for measurements
doc.fontSize(fontSize).font(fontName);
// Use provided positions or current document position
const startX = options.x ?? doc.x;
const startY = options.y ?? doc.y;
// Width must be provided for wrapping - no margin-based defaults
if (options.width === undefined) {
throw new Error('width is required for emoji text rendering');
}
const effectiveWidth = options.width;
// Split text into text/emoji segments
const segments = splitTextAndEmoji(text);
// Break segments into words for wrapping
const words: Array<{ type: 'text' | 'emoji'; content: string; width: number }> = [];
for (const segment of segments) {
if (segment.type === 'emoji') {
const emojiMetrics = measureEmoji(segment.content, fontSize);
words.push({
type: 'emoji',
content: segment.content,
width: emojiMetrics.width,
});
} else {
// Split text segment into words
const textWords = segment.content.split(/(\s+)/);
for (const word of textWords) {
if (word.length > 0) {
words.push({
type: 'text',
content: word,
width: doc.widthOfString(word),
});
}
}
}
}
// Wrap words into lines
const lines: Array<Array<{ type: 'text' | 'emoji'; content: string; width: number }>> = [];
let currentLine: Array<{ type: 'text' | 'emoji'; content: string; width: number }> = [];
let currentLineWidth = 0;
for (const word of words) {
const wordWidth = word.width;
if (currentLineWidth + wordWidth > effectiveWidth + WRAP_EPSILON && currentLine.length > 0) {
// Start a new line
lines.push(currentLine);
currentLine = [word];
currentLineWidth = wordWidth;
} else {
// Add to current line
currentLine.push(word);
currentLineWidth += wordWidth;
}
}
// Add the last line
if (currentLine.length > 0) {
lines.push(currentLine);
}
// Get actual line height from PDFKit (matches PDFKit's internal calculation)
// currentLineHeight(true) = font's natural height with built-in gap
// + lineGap = any extra spacing user requested
const lineHeight = doc.currentLineHeight(true) + (options.lineGap ?? 0);
// Render each line
let currentY = startY;
for (let lineIndex = 0; lineIndex < lines.length; lineIndex++) {
const line = lines[lineIndex];
if (!line) continue;
let currentX = startX;
// Render each word in the line
for (let i = 0; i < line.length; i++) {
const word = line[i];
if (!word) continue;
if (word.type === 'text') {
// Render text
doc.text(word.content, currentX, currentY, {
continued: false,
lineBreak: false,
});
currentX += word.width;
} else {
// Render emoji as inline image
const emojiMetrics = measureEmoji(word.content, fontSize);
const emojiBuffer = renderEmojiToBuffer(word.content, fontSize);
if (emojiBuffer) {
// Position emoji using measured baseline offset
const emojiY = currentY + emojiMetrics.baselineOffset;
doc.image(emojiBuffer, currentX, emojiY, {
width: emojiMetrics.width,
height: emojiMetrics.height,
});
}
currentX += word.width;
}
}
// Move to next line
currentY += lineHeight;
}
// Update document cursor position
doc.x = startX;
doc.y = currentY;
// Apply moveDown if specified
if (options.moveDown !== undefined) {
doc.moveDown(options.moveDown);
}
}
