shrink fonts

package.json

@@ -31,6 +31,7 @@
     "better-lock": "^3.2.0",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.14.2",
+    "fontmin": "^1.1.1",
     "lodash": "^4.17.21",
     "moment": "^2.30.1",
     "nesties": "^1.1.2",

src/app.service.ts

@@ -84,6 +84,7 @@ export class AppService extends ConsoleLogger {
     const copyFirstPageToBottom = async () => {
       const [newPage] = await doc.copyPages(doc, [0]);
       doc.addPage(newPage);
+      this.drawTextService.duplicateOperations(doc, 0, doc.getPageCount() - 1);
     };
 
     const cards = [...new Set([...ydk.main, ...ydk.extra, ...ydk.side])];
@@ -140,7 +141,6 @@ export class AppService extends ConsoleLogger {
         return grouped.length > 20;
       })
     ) {
-      await copyFirstPageToBottom();
       this.log(
         `Added extra page to PDF for deck export due to card type overflow.`,
       );
@@ -198,7 +198,7 @@ export class AppService extends ConsoleLogger {
         const usePages = _.chunk(groupedCards, spaces);
         await ensurePages(usePages.length - 1);
         for (let i = 0; i < usePages.length; ++i) {
-          await drawCardsOnPage(usePages[i], i + 1);
+          await drawCardsOnPage(usePages[i], i);
         }
       } else {
         await drawCardsOnPage(groupedCards, 0);
@@ -215,9 +215,7 @@ export class AppService extends ConsoleLogger {
     await drawCards(ydk.side, Coordinates.side, 15);
     this.log(`Filled side deck cards.`);
 
-    if (needExtraPage) {
-      doc.removePage(0);
-    }
+    await this.drawTextService.runBatch(doc);
 
     const resBuf = Buffer.from(await doc.save());
     this.log(`Generated PDF buffer for deck export.`);

src/draw-text/draw-text.service.ts

 import { Injectable } from '@nestjs/common';
-import * as fs from 'node:fs';
 import { PDFDocument, PDFFont, rgb } from 'pdf-lib';
 import { DrawTextOptions } from './draw-text-options';
 import fontkit from '@pdf-lib/fontkit';
+import Fontmin from 'fontmin';
+
+type Operation = {
+  kind: 'drawTextInBox';
+  text: string;
+  options: DrawTextOptions;
+  pageIndex: number; // 对应你之前的 pageCount 参数
+};
 
 @Injectable()
 export class DrawTextService {
   private fontCache = new WeakMap<PDFDocument, PDFFont>();
+  private operations = new WeakMap<PDFDocument, Operation[]>();
 
+  /*
   async getFont(doc: PDFDocument): Promise<PDFFont> {
     const cached = this.fontCache.get(doc);
     if (cached) return cached;
 
     const fontBuffer = await fs.promises.readFile('./resources/textFont.ttf');
     doc.registerFontkit(fontkit);
-    const font = await doc.embedFont(fontBuffer);
+    const font = await doc.embedFont(fontBuffer); // 注意：这是不裁剪的全量嵌入
     this.fontCache.set(doc, font);
     return font;
   }
+  */
+
+  /** 内部：确保 doc 对应的操作队列存在 */
+  private ensureOps(doc: PDFDocument): Operation[] {
+    let ops = this.operations.get(doc);
+    if (!ops) {
+      ops = [];
+      this.operations.set(doc, ops);
+    }
+    return ops;
+  }
 
   /**
-   * 在指定矩形内绘制文本（自动居中、缩放、截断）
+   * 在指定矩形内绘制文本（改为仅记录步骤；仍保持 async 签名以兼容调用端）
    */
   async drawTextInBox(
     doc: PDFDocument,
     text: string,
     options: DrawTextOptions,
     pageCount = 0,
-  ) {
+  ): Promise<void> {
     if (!text) return;
+    const ops = this.ensureOps(doc);
+    ops.push({
+      kind: 'drawTextInBox',
+      text,
+      options,
+      pageIndex: pageCount,
+    });
+  }
+
+  /**
+   * 批量执行所有已记录的绘制步骤：
+   * 1) 统计字符集合并子集化字体
+   * 2) 一次性 embed 子集字体
+   * 3) 回放所有操作并绘制
+   */
+  async runBatch(doc: PDFDocument): Promise<void> {
+    const ops = this.operations.get(doc) ?? [];
+    if (ops.length === 0) return;
+
+    // 1) 收集字符（为安全起见，用原始文本全集合来子集化）
+    const allText = ops
+      .filter((op) => op.kind === 'drawTextInBox')
+      .map((op) => op.text)
+      .join('');
+    const uniqueChars = Array.from(new Set([...allText])).join('');
+
+    // 2) 子集化字体到 Buffer（内存中完成，不落盘）
+    const subsetBuffer = await this.subsetFontToBuffer(
+      './resources/textFont.ttf',
+      uniqueChars,
+    );
+
+    // 3) embed 子集字体并缓存
+    doc.registerFontkit(fontkit);
+    const subsetFont = await doc.embedFont(subsetBuffer);
+    this.fontCache.set(doc, subsetFont);
+
+    // 4) 回放并实际绘制
+    for (const op of ops) {
+      if (op.kind === 'drawTextInBox') {
+        await this.drawTextInBoxWithFont(
+          doc,
+          subsetFont,
+          op.text,
+          op.options,
+          op.pageIndex,
+        );
+      }
+    }
+
+    // 5) 清空本次操作队列（避免重复执行）
+    this.operations.delete(doc);
+  }
+
+  /**
+   * 实际绘制（把你原本的测量/缩放/截断逻辑搬到这里，并显式使用传入的 PDFFont）
+   */
+  private async drawTextInBoxWithFont(
+    doc: PDFDocument,
+    font: PDFFont,
+    text: string,
+    options: DrawTextOptions,
+    pageIndex: number,
+  ): Promise<void> {
+    if (!text) return;
+
     const { x, y, width, height, fontSize } = options;
-    const page = doc.getPage(pageCount);
+    const page = doc.getPage(pageIndex);
 
-    const font = await this.getFont(doc);
     let size = fontSize;
 
     // 测量宽度并调整大小防止越界
@@ -78,4 +163,48 @@ export class DrawTextService {
       lineHeight: size * 1.1,
     });
   }
+
+  /**
+   * 使用 fontmin 在内存中对子集化字体并返回 Buffer
+   * - 若使用 OTF，请先转 TTF 或改用其它子集工具
+   */
+  private async subsetFontToBuffer(
+    fontPath: string,
+    text: string,
+  ): Promise<Buffer> {
+    const uniqText = Array.from(new Set([...text])).join('');
+    return new Promise<Buffer>((resolve, reject) => {
+      const fm = new Fontmin().src(fontPath).use(
+        Fontmin.glyph({
+          text: uniqText,
+          hinting: true, // 尽量保留 hinting，视字体而定
+        }),
+      );
+      // 不调用 .dest()，只走内存
+      // @ts-ignore
+      fm.run((err, files: { contents: Buffer }[]) => {
+        if (err) return reject(err);
+        const out = files.find((f) => Buffer.isBuffer(f.contents));
+        // console.log(files);
+        if (!out) return reject(new Error('Fontmin produced no buffer output'));
+        resolve(out.contents);
+      });
+    });
+  }
+
+  duplicateOperations(doc: PDFDocument, fromPage: number, toPage: number) {
+    const ops = this.operations.get(doc);
+    if (!ops) return;
+
+    const newOps: Operation[] = [];
+    for (const op of ops) {
+      if (op.pageIndex === fromPage) {
+        newOps.push({
+          ...op,
+          pageIndex: toPage,
+        });
+      }
+    }
+    ops.push(...newOps);
+  }
 }