NapCatQQ source snapshot

packages/napcat-image-size/package.json

@@ -0,0 +1,21 @@
+{
+    "name": "napcat-image-size",
+    "version": "0.0.1",
+    "private": true,
+    "type": "module",
+    "main": "src/index.ts",
+    "exports": {
+        ".": {
+            "import": "./src/index.ts"
+        },
+        "./src/*": {
+            "import": "./src/*"
+        }
+    },
+    "devDependencies": {
+        "@types/node": "^22.0.1"
+    },
+    "engines": {
+        "node": ">=18.0.0"
+    }
+}

packages/napcat-image-size/src/index.ts

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+import { BmpParser } from '@/napcat-image-size/src/parser/BmpParser';
+import { GifParser } from '@/napcat-image-size/src/parser/GifParser';
+import { JpegParser } from '@/napcat-image-size/src/parser/JpegParser';
+import { PngParser } from '@/napcat-image-size/src/parser/PngParser';
+import { TiffParser } from '@/napcat-image-size/src/parser/TiffParser';
+import { WebpParser } from '@/napcat-image-size/src/parser/WebpParser';
+import * as fs from 'fs';
+import { ReadStream } from 'fs';
+import { Readable } from 'stream';
+
+export interface ImageSize {
+  width: number;
+  height: number;
+}
+
+export enum ImageType {
+  JPEG = 'jpeg',
+  PNG = 'png',
+  BMP = 'bmp',
+  GIF = 'gif',
+  WEBP = 'webp',
+  TIFF = 'tiff',
+  UNKNOWN = 'unknown',
+}
+
+export interface ImageParser {
+  readonly type: ImageType;
+  canParse (buffer: Buffer): boolean;
+  parseSize (stream: ReadStream): Promise<ImageSize | undefined>;
+}
+
+// 魔术匹配
+export function matchMagic (buffer: Buffer, magic: number[], offset = 0): boolean {
+  if (buffer.length < offset + magic.length) {
+    return false;
+  }
+
+  for (let i = 0; i < magic.length; i++) {
+    if (buffer[offset + i] !== magic[i]) {
+      return false;
+    }
+  }
+  return true;
+}
+
+// 所有解析器实例
+const parserInstances = {
+  png: new PngParser(),
+  jpeg: new JpegParser(),
+  bmp: new BmpParser(),
+  gif: new GifParser(),
+  webp: new WebpParser(),
+  tiff: new TiffParser(),
+};
+
+// 首字节到可能的图片类型映射，用于快速筛选
+const firstByteMap = new Map<number, ImageType[]>([
+  [0x42, [ImageType.BMP]],       // 'B' - BMP
+  [0x47, [ImageType.GIF]],       // 'G' - GIF
+  [0x49, [ImageType.TIFF]],      // 'I' - TIFF (II - little endian)
+  [0x4D, [ImageType.TIFF]],      // 'M' - TIFF (MM - big endian)
+  [0x52, [ImageType.WEBP]],      // 'R' - RIFF (WebP)
+  [0x89, [ImageType.PNG]],       // PNG signature
+  [0xFF, [ImageType.JPEG]],      // JPEG SOI
+]);
+
+// 类型到解析器的映射
+const typeToParser = new Map<ImageType, ImageParser>([
+  [ImageType.PNG, parserInstances.png],
+  [ImageType.JPEG, parserInstances.jpeg],
+  [ImageType.BMP, parserInstances.bmp],
+  [ImageType.GIF, parserInstances.gif],
+  [ImageType.WEBP, parserInstances.webp],
+  [ImageType.TIFF, parserInstances.tiff],
+]);
+
+// 所有解析器列表（用于回退）
+const parsers: ReadonlyArray<ImageParser> = Object.values(parserInstances);
+
+export async function detectImageType (filePath: string): Promise<ImageType> {
+  return new Promise((resolve, reject) => {
+    const stream = fs.createReadStream(filePath, {
+      highWaterMark: 64, // 优化读取buffer大小
+      start: 0,
+      end: 63,
+    });
+
+    const chunks: Buffer[] = [];
+
+    stream.on('error', (err) => {
+      stream.destroy();
+      reject(err);
+    });
+
+    stream.on('data', (chunk: Buffer | string) => {
+      const chunkBuffer = Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk);
+      chunks.push(chunkBuffer);
+    });
+
+    stream.on('end', () => {
+      const buffer = Buffer.concat(chunks);
+
+      if (buffer.length === 0) {
+        return resolve(ImageType.UNKNOWN);
+      }
+
+      for (const parser of parsers) {
+        if (parser.canParse(buffer)) {
+          return resolve(parser.type);
+        }
+      }
+
+      resolve(ImageType.UNKNOWN);
+    });
+  });
+}
+
+export async function imageSizeFromFile (filePath: string): Promise<ImageSize | undefined> {
+  try {
+    // 先检测类型
+    const type = await detectImageType(filePath);
+    const parser = typeToParser.get(type);
+    if (!parser) {
+      return undefined;
+    }
+
+    // 用流式方式解析尺寸
+    const stream = fs.createReadStream(filePath);
+    try {
+      return await parser.parseSize(stream);
+    } catch (err) {
+      console.error(`解析图片尺寸出错: ${err}`);
+      return undefined;
+    } finally {
+      if (!stream.destroyed) {
+        stream.destroy();
+      }
+    }
+  } catch (err) {
+    console.error(`检测图片类型出错: ${err}`);
+    return undefined;
+  }
+}
+
+export async function imageSizeFallBack (
+  filePath: string,
+  fallback: ImageSize = {
+    width: 1024,
+    height: 1024,
+  }
+): Promise<ImageSize> {
+  return await imageSizeFromFile(filePath) ?? fallback;
+}
+
+// 从 Buffer 创建可读流
+function bufferToReadStream (buffer: Buffer): ReadStream {
+  const readable = new Readable({
+    read () {
+      this.push(buffer);
+      this.push(null);
+    },
+  });
+  return readable as unknown as ReadStream;
+}
+
+// 从 Buffer 检测图片类型（使用首字节快速筛选）
+export function detectImageTypeFromBuffer (buffer: Buffer): ImageType {
+  if (buffer.length === 0) {
+    return ImageType.UNKNOWN;
+  }
+
+  const firstByte = buffer[0]!;
+  const possibleTypes = firstByteMap.get(firstByte);
+
+  if (possibleTypes) {
+    // 根据首字节快速筛选可能的类型
+    for (const type of possibleTypes) {
+      const parser = typeToParser.get(type);
+      if (parser && parser.canParse(buffer)) {
+        return parser.type;
+      }
+    }
+  }
+
+  // 回退：遍历所有解析器
+  for (const parser of parsers) {
+    if (parser.canParse(buffer)) {
+      return parser.type;
+    }
+  }
+
+  return ImageType.UNKNOWN;
+}
+
+// 从 Buffer 解析图片尺寸
+export async function imageSizeFromBuffer (buffer: Buffer): Promise<ImageSize | undefined> {
+  const type = detectImageTypeFromBuffer(buffer);
+  const parser = typeToParser.get(type);
+  if (!parser) {
+    return undefined;
+  }
+
+  try {
+    const stream = bufferToReadStream(buffer);
+    return await parser.parseSize(stream);
+  } catch (err) {
+    console.error(`解析图片尺寸出错: ${err}`);
+    return undefined;
+  }
+}
+
+// 从 Buffer 解析图片尺寸，带回退值
+export async function imageSizeFromBufferFallBack (
+  buffer: Buffer,
+  fallback: ImageSize = {
+    width: 1024,
+    height: 1024,
+  }
+): Promise<ImageSize> {
+  return await imageSizeFromBuffer(buffer) ?? fallback;
+}

packages/napcat-image-size/src/parser/BmpParser.ts

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+import { ImageParser, ImageType, matchMagic, ImageSize } from '@/napcat-image-size/src';
+import { ReadStream } from 'fs';
+
+// BMP解析器
+export class BmpParser implements ImageParser {
+  readonly type = ImageType.BMP;
+  // BMP 魔术头：42 4D (BM)
+  private readonly BMP_SIGNATURE = [0x42, 0x4D];
+
+  canParse (buffer: Buffer): boolean {
+    return matchMagic(buffer, this.BMP_SIGNATURE);
+  }
+
+  async parseSize (stream: ReadStream): Promise<ImageSize | undefined> {
+    return new Promise((resolve, reject) => {
+      stream.once('error', reject);
+      stream.once('readable', () => {
+        const buf = stream.read(26) as Buffer;
+        if (!buf || buf.length < 26) {
+          return resolve(undefined);
+        }
+        if (this.canParse(buf)) {
+          const width = buf.readUInt32LE(18);
+          const height = buf.readUInt32LE(22);
+          resolve({ width, height });
+        } else {
+          resolve(undefined);
+        }
+      });
+    });
+  }
+}

packages/napcat-image-size/src/parser/GifParser.ts

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+import { ImageParser, ImageType, matchMagic, ImageSize } from '@/napcat-image-size/src';
+import { ReadStream } from 'fs';
+
+// GIF解析器
+export class GifParser implements ImageParser {
+  readonly type = ImageType.GIF;
+  // GIF87a 魔术头：47 49 46 38 37 61
+  private readonly GIF87A_SIGNATURE = [0x47, 0x49, 0x46, 0x38, 0x37, 0x61];
+  // GIF89a 魔术头：47 49 46 38 39 61
+  private readonly GIF89A_SIGNATURE = [0x47, 0x49, 0x46, 0x38, 0x39, 0x61];
+
+  canParse (buffer: Buffer): boolean {
+    return (
+      matchMagic(buffer, this.GIF87A_SIGNATURE) ||
+      matchMagic(buffer, this.GIF89A_SIGNATURE)
+    );
+  }
+
+  async parseSize (stream: ReadStream): Promise<ImageSize | undefined> {
+    return new Promise((resolve, reject) => {
+      stream.once('error', reject);
+      stream.once('readable', () => {
+        const buf = stream.read(10) as Buffer;
+        if (!buf || buf.length < 10) {
+          return resolve(undefined);
+        }
+        if (this.canParse(buf)) {
+          const width = buf.readUInt16LE(6);
+          const height = buf.readUInt16LE(8);
+          resolve({ width, height });
+        } else {
+          resolve(undefined);
+        }
+      });
+    });
+  }
+}

packages/napcat-image-size/src/parser/JpegParser.ts

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+import { ImageParser, ImageType, matchMagic, ImageSize } from '@/napcat-image-size/src';
+import { ReadStream } from 'fs';
+
+// JPEG解析器
+export class JpegParser implements ImageParser {
+  readonly type = ImageType.JPEG;
+  // JPEG 魔术头：FF D8
+  private readonly JPEG_SIGNATURE = [0xFF, 0xD8];
+
+  // JPEG标记常量
+  private readonly SOF_MARKERS = {
+    SOF0: 0xC0, // 基线DCT
+    SOF1: 0xC1, // 扩展顺序DCT
+    SOF2: 0xC2, // 渐进式DCT
+    SOF3: 0xC3, // 无损
+  } as const;
+
+  // 非SOF标记
+  private readonly NON_SOF_MARKERS: number[] = [
+    0xC4, // DHT
+    0xC8, // JPEG扩展
+    0xCC, // DAC
+  ] as const;
+
+  canParse (buffer: Buffer): boolean {
+    return matchMagic(buffer, this.JPEG_SIGNATURE);
+  }
+
+  isSOFMarker (marker: number): boolean {
+    return (
+      marker === this.SOF_MARKERS.SOF0 ||
+      marker === this.SOF_MARKERS.SOF1 ||
+      marker === this.SOF_MARKERS.SOF2 ||
+      marker === this.SOF_MARKERS.SOF3
+    );
+  }
+
+  isNonSOFMarker (marker: number): boolean {
+    return this.NON_SOF_MARKERS.includes(marker);
+  }
+
+  async parseSize (stream: ReadStream): Promise<ImageSize | undefined> {
+    return new Promise<ImageSize | undefined>((resolve, reject) => {
+      const BUFFER_SIZE = 1024; // 读取块大小，可以根据需要调整
+      let buffer = Buffer.alloc(0);
+      let offset = 0;
+      let found = false;
+
+      // 处理错误
+      stream.on('error', (err) => {
+        stream.destroy();
+        reject(err);
+      });
+
+      // 处理数据块
+      stream.on('data', (chunk: Buffer | string) => {
+        // 追加新数据到缓冲区
+        const chunkBuffer = Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk);
+        buffer = Buffer.concat([buffer.subarray(offset), chunkBuffer]);
+        offset = 0;
+
+        // 保持缓冲区在合理大小内，只保留最后的部分用于跨块匹配
+        const bufferSize = buffer.length;
+        const MIN_REQUIRED_BYTES = 10; // SOF段最低字节数
+
+        // 从JPEG头部后开始扫描
+        while (offset < bufferSize - MIN_REQUIRED_BYTES) {
+          // 寻找FF标记
+          if (buffer[offset] === 0xFF && buffer[offset + 1]! >= 0xC0 && buffer[offset + 1]! <= 0xCF) {
+            const marker = buffer[offset + 1];
+            if (!marker) {
+              break;
+            }
+            // 跳过非SOF标记
+            if (this.isNonSOFMarker(marker)) {
+              offset += 2;
+              continue;
+            }
+
+            // 处理SOF标记 (包含尺寸信息)
+            if (this.isSOFMarker(marker)) {
+              // 确保缓冲区中有足够数据读取尺寸
+              if (offset + 9 < bufferSize) {
+                // 解析尺寸: FF XX YY YY PP HH HH WW WW ...
+                // XX = 标记, YY YY = 段长度, PP = 精度, HH HH = 高, WW WW = 宽
+                const height = buffer.readUInt16BE(offset + 5);
+                const width = buffer.readUInt16BE(offset + 7);
+
+                found = true;
+                stream.destroy();
+                resolve({ width, height });
+                return;
+              } else {
+                // 如果缓冲区内数据不够，保留当前位置等待更多数据
+                break;
+              }
+            }
+          }
+
+          offset++;
+        }
+
+        // 缓冲区管理: 如果处理了许多数据但没找到标记，
+        // 保留最后N字节用于跨块匹配，丢弃之前的数据
+        if (offset > BUFFER_SIZE) {
+          const KEEP_BYTES = 20; // 保留足够数据以处理跨块边界的情况
+          if (offset > KEEP_BYTES) {
+            buffer = buffer.subarray(offset - KEEP_BYTES);
+            offset = KEEP_BYTES;
+          }
+        }
+      });
+
+      // 处理流结束
+      stream.on('end', () => {
+        if (!found) {
+          resolve(undefined);
+        }
+      });
+    });
+  }
+}

packages/napcat-image-size/src/parser/PngParser.ts

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+import { ImageParser, ImageType, matchMagic, ImageSize } from '@/napcat-image-size/src';
+import { ReadStream } from 'fs';
+
+// PNG解析器
+export class PngParser implements ImageParser {
+  readonly type = ImageType.PNG;
+  // PNG 魔术头：89 50 4E 47 0D 0A 1A 0A
+  private readonly PNG_SIGNATURE = [0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A];
+
+  canParse (buffer: Buffer): boolean {
+    return matchMagic(buffer, this.PNG_SIGNATURE);
+  }
+
+  async parseSize (stream: ReadStream): Promise<ImageSize | undefined> {
+    return new Promise((resolve, reject) => {
+      stream.once('error', reject);
+      stream.once('readable', () => {
+        const buf = stream.read(24) as Buffer;
+        if (!buf || buf.length < 24) {
+          return resolve(undefined);
+        }
+        if (this.canParse(buf)) {
+          const width = buf.readUInt32BE(16);
+          const height = buf.readUInt32BE(20);
+          resolve({ width, height });
+        } else {
+          resolve(undefined);
+        }
+      });
+    });
+  }
+}

packages/napcat-image-size/src/parser/TiffParser.ts

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+import { ImageParser, ImageType, matchMagic, ImageSize } from '@/napcat-image-size/src';
+import { ReadStream } from 'fs';
+
+// TIFF解析器
+export class TiffParser implements ImageParser {
+  readonly type = ImageType.TIFF;
+  // TIFF Little Endian 魔术头：49 49 2A 00 (II)
+  private readonly TIFF_LE_SIGNATURE = [0x49, 0x49, 0x2A, 0x00];
+  // TIFF Big Endian 魔术头：4D 4D 00 2A (MM)
+  private readonly TIFF_BE_SIGNATURE = [0x4D, 0x4D, 0x00, 0x2A];
+
+  canParse (buffer: Buffer): boolean {
+    return (
+      matchMagic(buffer, this.TIFF_LE_SIGNATURE) ||
+      matchMagic(buffer, this.TIFF_BE_SIGNATURE)
+    );
+  }
+
+  async parseSize (stream: ReadStream): Promise<ImageSize | undefined> {
+    return new Promise((resolve, reject) => {
+      const chunks: Buffer[] = [];
+      let totalBytes = 0;
+      const MAX_BYTES = 64 * 1024; // 最多读取 64KB
+
+      stream.on('error', reject);
+
+      stream.on('data', (chunk: Buffer | string) => {
+        const chunkBuffer = Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk);
+        chunks.push(chunkBuffer);
+        totalBytes += chunkBuffer.length;
+
+        if (totalBytes >= MAX_BYTES) {
+          stream.destroy();
+        }
+      });
+
+      stream.on('end', () => {
+        const buffer = Buffer.concat(chunks);
+        const size = this.parseTiffSize(buffer);
+        resolve(size);
+      });
+
+      stream.on('close', () => {
+        if (chunks.length > 0) {
+          const buffer = Buffer.concat(chunks);
+          const size = this.parseTiffSize(buffer);
+          resolve(size);
+        }
+      });
+    });
+  }
+
+  private parseTiffSize (buffer: Buffer): ImageSize | undefined {
+    if (buffer.length < 8) {
+      return undefined;
+    }
+
+    // 判断字节序
+    const isLittleEndian = buffer[0] === 0x49; // 'I'
+
+    const readUInt16 = isLittleEndian
+      ? (offset: number) => buffer.readUInt16LE(offset)
+      : (offset: number) => buffer.readUInt16BE(offset);
+
+    const readUInt32 = isLittleEndian
+      ? (offset: number) => buffer.readUInt32LE(offset)
+      : (offset: number) => buffer.readUInt32BE(offset);
+
+    // 获取第一个 IFD 的偏移量
+    const ifdOffset = readUInt32(4);
+    if (ifdOffset + 2 > buffer.length) {
+      return undefined;
+    }
+
+    // 读取 IFD 条目数量
+    const numEntries = readUInt16(ifdOffset);
+    let width: number | undefined;
+    let height: number | undefined;
+
+    // TIFF 标签
+    const TAG_IMAGE_WIDTH = 0x0100;
+    const TAG_IMAGE_HEIGHT = 0x0101;
+
+    // 遍历 IFD 条目
+    for (let i = 0; i < numEntries; i++) {
+      const entryOffset = ifdOffset + 2 + i * 12;
+      if (entryOffset + 12 > buffer.length) {
+        break;
+      }
+
+      const tag = readUInt16(entryOffset);
+      const type = readUInt16(entryOffset + 2);
+      // const count = readUInt32(entryOffset + 4);
+
+      // 根据类型读取值
+      let value: number;
+      if (type === 3) {
+        // SHORT (2 bytes)
+        value = readUInt16(entryOffset + 8);
+      } else if (type === 4) {
+        // LONG (4 bytes)
+        value = readUInt32(entryOffset + 8);
+      } else {
+        continue;
+      }
+
+      if (tag === TAG_IMAGE_WIDTH) {
+        width = value;
+      } else if (tag === TAG_IMAGE_HEIGHT) {
+        height = value;
+      }
+
+      if (width !== undefined && height !== undefined) {
+        return { width, height };
+      }
+    }
+
+    if (width !== undefined && height !== undefined) {
+      return { width, height };
+    }
+
+    return undefined;
+  }
+}

packages/napcat-image-size/src/parser/WebpParser.ts

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+import { ImageParser, ImageType, matchMagic, ImageSize } from '@/napcat-image-size/src';
+import { ReadStream } from 'fs';
+
+// WEBP解析器 - 完整支持VP8, VP8L, VP8X格式
+export class WebpParser implements ImageParser {
+  readonly type = ImageType.WEBP;
+  // WEBP RIFF 头：52 49 46 46 (RIFF)
+  private readonly RIFF_SIGNATURE = [0x52, 0x49, 0x46, 0x46];
+  // WEBP 魔术头：57 45 42 50 (WEBP)
+  private readonly WEBP_SIGNATURE = [0x57, 0x45, 0x42, 0x50];
+
+  // WEBP 块头
+  private readonly CHUNK_VP8 = [0x56, 0x50, 0x38, 0x20]; // "VP8 "
+  private readonly CHUNK_VP8L = [0x56, 0x50, 0x38, 0x4C]; // "VP8L"
+  private readonly CHUNK_VP8X = [0x56, 0x50, 0x38, 0x58]; // "VP8X"
+
+  canParse (buffer: Buffer): boolean {
+    return (
+      buffer.length >= 12 &&
+      matchMagic(buffer, this.RIFF_SIGNATURE, 0) &&
+      matchMagic(buffer, this.WEBP_SIGNATURE, 8)
+    );
+  }
+
+  isChunkType (buffer: Buffer, offset: number, chunkType: number[]): boolean {
+    return buffer.length >= offset + 4 && matchMagic(buffer, chunkType, offset);
+  }
+
+  async parseSize (stream: ReadStream): Promise<ImageSize | undefined> {
+    return new Promise((resolve, reject) => {
+      // 需要读取足够的字节来检测所有三种格式
+      const MAX_HEADER_SIZE = 32;
+      let totalBytes = 0;
+      let buffer = Buffer.alloc(0);
+
+      stream.on('error', reject);
+
+      stream.on('data', (chunk: Buffer | string) => {
+        const chunkBuffer = Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk);
+        buffer = Buffer.concat([buffer, chunkBuffer]);
+        totalBytes += chunk.length;
+
+        // 检查是否有足够的字节进行格式检测
+        if (totalBytes >= MAX_HEADER_SIZE) {
+          stream.destroy();
+
+          // 检查基本的WEBP签名
+          if (!this.canParse(buffer)) {
+            return resolve(undefined);
+          }
+
+          // 检查chunk头部，位于字节12-15
+          if (this.isChunkType(buffer, 12, this.CHUNK_VP8)) {
+            // VP8格式 - 标准WebP
+            // 宽度和高度在帧头中
+            const width = buffer.readUInt16LE(26) & 0x3FFF;
+            const height = buffer.readUInt16LE(28) & 0x3FFF;
+            return resolve({ width, height });
+          } else if (this.isChunkType(buffer, 12, this.CHUNK_VP8L)) {
+            // VP8L格式 - 无损WebP
+            // 1字节标记后是14位宽度和14位高度
+            const bits = buffer.readUInt32LE(21);
+            const width = 1 + (bits & 0x3FFF);
+            const height = 1 + ((bits >> 14) & 0x3FFF);
+            return resolve({ width, height });
+          } else if (this.isChunkType(buffer, 12, this.CHUNK_VP8X)) {
+            // VP8X格式 - 扩展WebP
+            // 24位宽度和高度(减去1)
+            if (buffer.length < 30) {
+              return resolve(undefined);
+            }
+            const width = 1 + ((buffer[24]! | (buffer[25]! << 8) | (buffer[26]! << 16)) & 0xFFFFFF);
+            const height = 1 + ((buffer[27]! | (buffer[28]! << 8) | (buffer[29]! << 16)) & 0xFFFFFF);
+            return resolve({ width, height });
+          } else {
+            // 未知的WebP子格式
+            return resolve(undefined);
+          }
+        }
+      });
+
+      stream.on('end', () => {
+        // 如果没有读到足够的字节
+        if (totalBytes < MAX_HEADER_SIZE) {
+          resolve(undefined);
+        }
+      });
+    });
+  }
+}

packages/napcat-image-size/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "include": [
+    "src/**/*.ts"
+  ],
+  "exclude": [
+    "node_modules",
+    "dist"
+  ]
+}