Create app.py

app.py

@@ -0,0 +1,167 @@
+import streamlit as st
+import os
+import zipfile
+from pathlib import Path
+import tempfile
+import shutil
+
+def is_safe_extension(extension):
+    """Check if the extension is safe to convert to"""
+    dangerous_extensions = ['.exe', '.bin', '.bat', '.cmd', '.com', '.scr', '.pif', '.vbs', '.js']
+    return extension.lower() not in dangerous_extensions
+
+def change_file_extension(file_content, original_name, new_extension):
+    """Change file extension and return new filename"""
+    # Remove the dot if user includes it
+    if new_extension.startswith('.'):
+        new_extension = new_extension[1:]
+    
+    # Get the base name without extension
+    base_name = Path(original_name).stem
+    
+    # Create new filename
+    new_filename = f"{base_name}.{new_extension}"
+    
+    return new_filename, file_content
+
+def create_download_zip(files_data):
+    """Create a zip file containing all converted files"""
+    # Create a temporary directory
+    with tempfile.TemporaryDirectory() as temp_dir:
+        zip_path = os.path.join(temp_dir, "converted_files.zip")
+        
+        with zipfile.ZipFile(zip_path, 'w') as zipf:
+            for filename, content in files_data:
+                zipf.writestr(filename, content)
+        
+        # Read the zip file content
+        with open(zip_path, 'rb') as f:
+            zip_content = f.read()
+    
+    return zip_content
+
+def main():
+    st.set_page_config(
+        page_title="File Extension Converter",
+        page_icon="🔄",
+        layout="wide"
+    )
+    
+    st.title("🔄 File Extension Converter")
+    st.markdown("Convert any file extension to another (safely)")
+    
+    # Sidebar with instructions
+    with st.sidebar:
+        st.header("📋 Instructions")
+        st.markdown("""
+        1. Upload one or more files
+        2. Enter the target extension
+        3. Download converted files
+        
+        **Safety Note:** 
+        - .exe and .bin files are blocked for security
+        - Only the extension is changed, not the file content
+        """)
+        
+        st.header("⚠️ Blocked Extensions")
+        st.code(".exe, .bin, .bat, .cmd, .com, .scr, .pif, .vbs, .js")
+    
+    # Main interface
+    col1, col2 = st.columns([2, 1])
+    
+    with col1:
+        st.header("Upload Files")
+        uploaded_files = st.file_uploader(
+            "Choose files to convert",
+            accept_multiple_files=True,
+            help="Upload any files you want to change the extension for"
+        )
+    
+    with col2:
+        st.header("Target Extension")
+        new_extension = st.text_input(
+            "New extension",
+            placeholder="e.g., txt, pdf, jpg",
+            help="Enter the extension you want to convert to (without the dot)"
+        ).strip()
+    
+    if uploaded_files and new_extension:
+        # Validate extension
+        if new_extension.startswith('.'):
+            new_extension = new_extension[1:]
+        
+        full_extension = f".{new_extension}"
+        
+        if not is_safe_extension(full_extension):
+            st.error(f"❌ Extension '{full_extension}' is not allowed for security reasons")
+            return
+        
+        st.success(f"✅ Converting to: **{full_extension}**")
+        
+        # Process files
+        converted_files = []
+        results_data = []
+        
+        st.header("📁 Conversion Results")
+        
+        for uploaded_file in uploaded_files:
+            original_name = uploaded_file.name
+            file_content = uploaded_file.read()
+            
+            # Convert extension
+            new_filename, new_content = change_file_extension(
+                file_content, original_name, new_extension
+            )
+            
+            converted_files.append((new_filename, new_content))
+            
+            # Display result
+            col_orig, col_arrow, col_new = st.columns([3, 1, 3])
+            with col_orig:
+                st.text(f"📄 {original_name}")
+            with col_arrow:
+                st.text("➡️")
+            with col_new:
+                st.text(f"📄 {new_filename}")
+        
+        st.divider()
+        
+        # Download options
+        st.header("💾 Download")
+        
+        if len(converted_files) == 1:
+            # Single file download
+            filename, content = converted_files[0]
+            st.download_button(
+                label=f"📥 Download {filename}",
+                data=content,
+                file_name=filename,
+                mime="application/octet-stream"
+            )
+        else:
+            # Multiple files - create zip
+            zip_content = create_download_zip(converted_files)
+            st.download_button(
+                label=f"📥 Download All Files ({len(converted_files)} files)",
+                data=zip_content,
+                file_name="converted_files.zip",
+                mime="application/zip"
+            )
+            
+            st.info(f"💡 {len(converted_files)} files will be downloaded as a ZIP archive")
+    
+    elif uploaded_files and not new_extension:
+        st.warning("⚠️ Please enter a target extension")
+    elif new_extension and not uploaded_files:
+        st.warning("⚠️ Please upload files to convert")
+    
+    # Footer
+    st.divider()
+    st.markdown("""
+    <div style='text-align: center; color: #666; font-size: 0.8em;'>
+        Built with Streamlit 🎈 | Safe file extension conversion
+    </div>
+    """, unsafe_allow_html=True)
+
+if __name__ == "__main__":
+    main()