From dcf34e6bd1853c8d8da005079b5b9cb1f34414b8 Mon Sep 17 00:00:00 2001
From: TiAmo <1711788888@qq.com>
Date: Fri, 23 Oct 2020 15:07:05 +0800
Subject: [PATCH] add WeChat.py.

---
 WeChat.py | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)
 create mode 100644 WeChat.py

diff --git a/WeChat.py b/WeChat.py
new file mode 100644
index 0000000..684b8ff
--- /dev/null
+++ b/WeChat.py
@@ -0,0 +1,80 @@
+"""
+dat文件和源图片文件就是用某个数按字节异或了一下，异或回来就可以了，
+A ^ B = C
+B ^ C = A
+A ^ C = B
+假设png文件头是A，dat文件是C，用A和C文件头的字节异或就可以得出B，因
+为图片的格式以png，jpg，gif为主，通过这三种文件格式的头两个字节和待
+转换文件的头两个字节一一异或的结果相等就找到B了，同时也知道了文件的
+格式
+"""
+
+import os
+import binascii
+from datetime import datetime
+
+def get_top_2hex(path):
+    """
+    获取文件的前两个16进制数
+    """
+    data = open(path,'rb')
+    hexstr = binascii.b2a_hex(data.read(2))
+    return str(hexstr[:2], 'utf8'), str(hexstr[2:4], 'utf8')
+
+"""
+JPG文件头16进制为0xFFD8FF
+PNG文件头16进制为0x89504E
+GIF文件头16进制为0x474946
+"""
+def parse(dir):
+    firstV, nextV = get_top_2hex(dir)
+    firstV = int(firstV, 16)
+    nextV = int(nextV, 16)
+    coder = firstV ^ 0xFF
+    kind = 'jpg'
+
+    if firstV ^ 0xFF == nextV ^ 0xD8:
+        coder = firstV ^ 0xFF
+        kind = 'jpg'
+    elif firstV ^ 0x89 == nextV ^ 0x50:
+        coder = firstV ^ 0x89
+        kind = 'png'
+    elif firstV ^ 0x47 == nextV ^ 0x49:
+        coder = firstV ^ 0x47
+        kind = 'gif'
+    
+    return coder, kind
+
+def convert(path, file_name):
+    file_path = os.path.join(path, file_name)
+    mk_time = datetime.fromtimestamp(os.path.getmtime(file_path)).strftime('%Y-%m-%d %H.%M.%S')
+    coder, kind = parse(file_path)
+
+    dir_name = path.split('\\')[-1]
+    if not os.path.exists(dir_name):
+        os.mkdir(dir_name)
+    
+    dat = open(file_path, "rb")
+    pic = open(dir_name + '\\' + mk_time + '-' + file_name[:10] + '.' + kind, "wb")
+
+    for cur in dat:
+        for item in cur:
+            pic.write(bytes([item ^ coder]))
+
+    dat.close()
+    pic.close()
+
+def do(path):
+    files = os.listdir(path)
+    print('total files:{}'.format(len(files)))
+    i = 0
+    for file_name in files:
+        try:
+            print('{} ... {}'.format(i, file_name))
+            convert(path, file_name)
+            i+=1
+        except:
+            pass
+
+if __name__=="__main__":
+    do(r"C:\Users\Administrator\Documents\WeChat Files\wxid_hyjv4sqk0uho22\FileStorage\Image\2020-04")
\ No newline at end of file