{"version":3,"file":"mime.d.ts","sourceRoot":"","sources":["../../src/utils/mime.ts"],"names":[],"mappings":"AAKA,wBAAgB,4BAA4B,CAAC,MAAM,EAAE,UAAU,GAAG,MAAM,GAAG,IAAI,CAc9E;AAED,wBAAsB,oCAAoC,CAAC,QAAQ,EAAE,MAAM,GAAG,OAAO,CAAC,MAAM,GAAG,IAAI,CAAC,CASnG","sourcesContent":["import { open } from \"node:fs/promises\";\n\nconst IMAGE_TYPE_SNIFF_BYTES = 4100;\nconst PNG_SIGNATURE = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a];\n\nexport function detectSupportedImageMimeType(buffer: Uint8Array): string | null {\n\tif (startsWith(buffer, [0xff, 0xd8, 0xff])) {\n\t\treturn buffer[3] === 0xf7 ? null : \"image/jpeg\";\n\t}\n\tif (startsWith(buffer, PNG_SIGNATURE)) {\n\t\treturn isPng(buffer) && !isAnimatedPng(buffer) ? \"image/png\" : null;\n\t}\n\tif (startsWithAscii(buffer, 0, \"GIF\")) {\n\t\treturn \"image/gif\";\n\t}\n\tif (startsWithAscii(buffer, 0, \"RIFF\") && startsWithAscii(buffer, 8, \"WEBP\")) {\n\t\treturn \"image/webp\";\n\t}\n\treturn null;\n}\n\nexport async function detectSupportedImageMimeTypeFromFile(filePath: string): Promise<string | null> {\n\tconst fileHandle = await open(filePath, \"r\");\n\ttry {\n\t\tconst buffer = Buffer.alloc(IMAGE_TYPE_SNIFF_BYTES);\n\t\tconst { bytesRead } = await fileHandle.read(buffer, 0, IMAGE_TYPE_SNIFF_BYTES, 0);\n\t\treturn detectSupportedImageMimeType(buffer.subarray(0, bytesRead));\n\t} finally {\n\t\tawait fileHandle.close();\n\t}\n}\n\nfunction isPng(buffer: Uint8Array): boolean {\n\treturn (\n\t\tbuffer.length >= 16 && readUint32BE(buffer, PNG_SIGNATURE.length) === 13 && startsWithAscii(buffer, 12, \"IHDR\")\n\t);\n}\n\nfunction isAnimatedPng(buffer: Uint8Array): boolean {\n\tlet offset = PNG_SIGNATURE.length;\n\twhile (offset + 8 <= buffer.length) {\n\t\tconst chunkLength = readUint32BE(buffer, offset);\n\t\tconst chunkTypeOffset = offset + 4;\n\t\tif (startsWithAscii(buffer, chunkTypeOffset, \"acTL\")) return true;\n\t\tif (startsWithAscii(buffer, chunkTypeOffset, \"IDAT\")) return false;\n\n\t\tconst nextOffset = offset + 8 + chunkLength + 4;\n\t\tif (nextOffset <= offset || nextOffset > buffer.length) return false;\n\t\toffset = nextOffset;\n\t}\n\treturn false;\n}\n\nfunction readUint32BE(buffer: Uint8Array, offset: number): number {\n\treturn (\n\t\t(buffer[offset] ?? 0) * 0x1000000 +\n\t\t((buffer[offset + 1] ?? 0) << 16) +\n\t\t((buffer[offset + 2] ?? 0) << 8) +\n\t\t(buffer[offset + 3] ?? 0)\n\t);\n}\n\nfunction startsWith(buffer: Uint8Array, bytes: number[]): boolean {\n\tif (buffer.length < bytes.length) return false;\n\treturn bytes.every((byte, index) => buffer[index] === byte);\n}\n\nfunction startsWithAscii(buffer: Uint8Array, offset: number, text: string): boolean {\n\tif (buffer.length < offset + text.length) return false;\n\tfor (let index = 0; index < text.length; index++) {\n\t\tif (buffer[offset + index] !== text.charCodeAt(index)) return false;\n\t}\n\treturn true;\n}\n"]}