Merge pull request #1 from andrestobelem/tar-epub-fixer

Enhance EPUB processing by implementing TAR file extraction functiona…

Author: andrestobelem

epub_fixer.py

@@ -0,0 +1,72 @@
+import os
+import tarfile
+import zipfile
+import sys
+
+def fix_epub_tar_to_zip(input_path, output_path):
+    """
+    Converts an EPUB file that is erroneously compressed as TAR 
+    to a correct EPUB ZIP file, normalizing its structure.
+    """
+    if not tarfile.is_tarfile(input_path):
+        print(f"Error: The file '{input_path}' is not a valid TAR file.")
+        return False
+
+    print(f"Opening TAR: {input_path}")
+    
+    with tarfile.open(input_path, "r:*") as tar:
+        members = tar.getmembers()
+        
+        # 1. Identify the root by locating the 'mimetype' file
+        mimetype_member = next((m for m in members if os.path.basename(m.name) == 'mimetype'), None)
+        
+        if not mimetype_member:
+            print("Error: 'mimetype' file not found. Is this a valid EPUB?")
+            return False
+            
+        root = os.path.dirname(mimetype_member.name)
+        if root and not root.endswith('/'):
+            root += '/'
+            
+        if root:
+            print(f"Detected root directory: {root} (it will be stripped)")
+        else:
+            print("The file is already at the root level.")
+
+        # 2. Create the new ZIP file (correct EPUB)
+        print(f"Creating ZIP: {output_path}")
+        with zipfile.ZipFile(output_path, "w", zipfile.ZIP_DEFLATED) as zip_file:
+            for member in members:
+                if member.isfile():
+                    # Extract content
+                    f = tar.extractfile(member)
+                    if f:
+                        # Normalize path: strip the root prefix if it exists
+                        arcname = member.name[len(root):] if member.name.startswith(root) else member.name
+                        
+                        # Write to ZIP
+                        zip_file.writestr(arcname, f.read())
+                        print(f"  + {arcname}")
+
+    print(f"\nSuccess! Fixed file saved at: {output_path}")
+    return True
+
+if __name__ == "__main__":
+    if len(sys.argv) < 2:
+        print("Usage: python epub_fixer.py <input_file.epub> [output_file.epub]")
+        sys.exit(1)
+
+    input_file = sys.argv[1]
+    
+    if len(sys.argv) > 2:
+        output_file = sys.argv[2]
+    else:
+        # Default: append '_fixed' to the filename
+        base, ext = os.path.splitext(input_file)
+        output_file = f"{base}_fixed{ext}"
+
+    if fix_epub_tar_to_zip(input_file, output_file):
+        print("\nProcess finished.")
+    else:
+        sys.exit(1)
+