From 32acbd8579463bfdec4536dc0b83b3c28c56f48a Mon Sep 17 00:00:00 2001
From: Balearica <admin@scribeocr.com>
Date: Thu, 1 Jun 2023 23:32:04 -0700
Subject: [PATCH] Removed file-type dependency per #711 (#775)

---
 package-lock.json                   | 14 --------------
 package.json                        |  1 -
 src/worker-script/index.js          |  7 ++++---
 src/worker-script/utils/setImage.js |  6 +++---
 4 files changed, 7 insertions(+), 21 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index 1f4ee72..af7063c 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -11,7 +11,6 @@
       "license": "Apache-2.0",
       "dependencies": {
         "bmp-js": "^0.1.0",
-        "file-type": "^12.4.2",
         "idb-keyval": "^6.2.0",
         "is-electron": "^2.2.2",
         "is-url": "^1.2.4",
@@ -4576,14 +4575,6 @@
         "node": "^10.12.0 || >=12.0.0"
       }
     },
-    "node_modules/file-type": {
-      "version": "12.4.2",
-      "resolved": "https://registry.npmjs.org/file-type/-/file-type-12.4.2.tgz",
-      "integrity": "sha512-UssQP5ZgIOKelfsaB5CuGAL+Y+q7EmONuiwF3N5HAH0t27rvrttgi6Ra9k/+DVaY9UF6+ybxu5pOXLUdA8N7Vg==",
-      "engines": {
-        "node": ">=8"
-      }
-    },
     "node_modules/fill-range": {
       "version": "7.0.1",
       "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.0.1.tgz",
@@ -13051,11 +13042,6 @@
         "flat-cache": "^3.0.4"
       }
     },
-    "file-type": {
-      "version": "12.4.2",
-      "resolved": "https://registry.npmjs.org/file-type/-/file-type-12.4.2.tgz",
-      "integrity": "sha512-UssQP5ZgIOKelfsaB5CuGAL+Y+q7EmONuiwF3N5HAH0t27rvrttgi6Ra9k/+DVaY9UF6+ybxu5pOXLUdA8N7Vg=="
-    },
     "fill-range": {
       "version": "7.0.1",
       "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.0.1.tgz",
diff --git a/package.json b/package.json
index 0a4e59b..fa327cd 100644
--- a/package.json
+++ b/package.json
@@ -63,7 +63,6 @@
   },
   "dependencies": {
     "bmp-js": "^0.1.0",
-    "file-type": "^12.4.2",
     "idb-keyval": "^6.2.0",
     "is-electron": "^2.2.2",
     "is-url": "^1.2.4",
diff --git a/src/worker-script/index.js b/src/worker-script/index.js
index 30e701f..959589e 100644
--- a/src/worker-script/index.js
+++ b/src/worker-script/index.js
@@ -8,7 +8,6 @@
  * @author Jerome Wu <jeromewus@gmail.com>
  */
 require('regenerator-runtime/runtime');
-const fileType = require('file-type');
 const isURL = require('is-url');
 const dump = require('./utils/dump');
 const isWebWorker = require('../utils/getEnvironment')('type') === 'webworker';
@@ -125,8 +124,10 @@ res) => {
 
     data = new Uint8Array(data);
 
-    const type = fileType(data);
-    if (typeof type !== 'undefined' && type.mime === 'application/gzip') {
+    // Check for gzip magic numbers (1F and 8B in hex)
+    const isGzip = (data[0] === 31 && data[1] === 139) || (data[1] === 31 && data[0] === 139);
+
+    if (isGzip) {
       data = adapter.gunzip(data);
     }
 
diff --git a/src/worker-script/utils/setImage.js b/src/worker-script/utils/setImage.js
index d9aec9b..354521f 100644
--- a/src/worker-script/utils/setImage.js
+++ b/src/worker-script/utils/setImage.js
@@ -1,5 +1,4 @@
 const bmp = require('bmp-js');
-const fileType = require('file-type');
 
 /**
  * setImage
@@ -9,7 +8,8 @@ const fileType = require('file-type');
  * @access public
  */
 module.exports = (TessModule, api, image, angle = 0) => {
-  const type = fileType(image);
+  // Check for bmp magic numbers (42 and 4D in hex)
+  const isBmp = (image[0] === 66 && image[1] === 77) || (image[1] === 66 && image[0] === 77);
 
   const exif = image.slice(0, 500).toString().match(/\x01\x12\x00\x03\x00\x00\x00\x01\x00(.)/)?.[1]?.charCodeAt(0) || 1;
 
@@ -18,7 +18,7 @@ module.exports = (TessModule, api, image, angle = 0) => {
   //  * @see https://github.com/DanBloomberg/leptonica/issues/607#issuecomment-1068802516
   //  * We therefore use bmp-js to convert all bmp files into a format Leptonica is known to support
   //  */
-  if (type && type.mime === 'image/bmp') {
+  if (isBmp) {
     // Not sure what this line actually does, but removing breaks the function
     const buf = Buffer.from(Array.from({ ...image, length: Object.keys(image).length }));
     const bmpBuf = bmp.decode(buf);