FIXES_APPLIED.md

Translation Issues Fixed

Problems Addressed

1. Translation Not Working (Files Remained Untranslated)

Problem: Files were being processed but returned in the original language with 0 paragraphs translated.

Root Causes:

• Silent fallback behavior in translate_text() method
• No validation of translation results
• Missing error handling for API failures

Fixes Applied:

• Enhanced translate_text() method:

  • Added API key validation before making requests
  • Improved translation prompts for better results with Google Gemini 2.5 Pro
  • Removed silent fallback to original text - now raises exceptions on failure
  • Added validation to ensure translation actually occurred
  • Increased token limits for better translation quality

• Improved error handling:

  • Added comprehensive exception handling in translation workflows
  • Better validation of translated content
  • Detailed logging to track translation progress

• Enhanced validation:

  • Check for empty or unchanged translation results
  • Verify API responses before processing
  • Ensure at least some content gets translated

2. Format Preservation Issue

Problem: User wanted files to maintain original filename and format (PDF→Word→translate→PDF workflow)

Current Behavior: Created separate "translated_" prefixed files Desired Behavior: Receive PDF, convert to Word, translate, convert back to PDF with same filename

Fixes Applied:

• Modified translate_document() method:

  • Output file now uses original filename (no "translated_" prefix)
  • For PDF input: PDF→DOCX→translate→PDF with original filename
  • For DOCX input: DOCX→translate→DOCX with original filename

• Updated file handling in main.py:

  • Both original and translated files now use same filename
  • Better file copying and naming logic
  • Improved response structure

Technical Improvements

1. Robust Translation Logic

# Before: Silent fallback
if translation_failed:
    return original_text  # Silent failure

# After: Proper error handling  
if not translated or translated == text:
    raise Exception("Translation failed: received empty or unchanged text")

2. Enhanced Error Reporting

• Added detailed logging throughout the translation pipeline
• Better API error messages
• Validation at each step of the process

3. Format Preservation Workflow

PDF Input → LibreOffice Convert to DOCX → Translate DOCX → Convert back to PDF (same filename)
DOCX Input → Translate DOCX → Save as same filename

Testing

API Key Testing

Created test_api.py script to verify:

• OPENROUTER_API_KEY is set correctly
• API connection is working
• Basic translation functionality

Usage

Run the test script to verify setup:

python test_api.py

Expected Results

After these fixes:

1. Translation will work: Files will be actually translated, not returned unchanged
2. Format preserved: PDF files will be returned as PDF with same filename
3. Better error messages: Clear feedback when translation fails
4. Robust operation: Proper error handling instead of silent failures

Key Files Modified

1. translator.py:

   • Enhanced translate_text() method with validation
   • Improved translate_document() for format preservation
   • Better error handling in translate_docx() and translate_pdf_direct()

2. app/main.py:

   • Updated translation endpoint with better validation
   • Fixed file naming to preserve original names
   • Enhanced error reporting

3. test_api.py (new):

   • API key and connection testing
   • Basic translation functionality verification

Usage Instructions

1. Set API Key: Ensure OPENROUTER_API_KEY environment variable is set
2. Test Setup: Run python test_api.py to verify configuration
3. Upload Files: PDF or DOCX files will now be properly translated
4. Download Results: Translated files maintain original format and filename

The system now provides reliable translation with proper format preservation as requested.