import os
import requests
import asyncio
import aiohttp
import subprocess
import tempfile
from pathlib import Path
from typing import List, Dict, Optional, Tuple, Any
from dataclasses import dataclass
import logging
from docx import Document
from docx.shared import Inches
import time
import json
from PyPDF2 import PdfReader
import pypdfium2 as pdfium
import pdfplumber
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
from reportlab.lib.utils import simpleSplit
import io

logger = logging.getLogger(__name__)

@dataclass
class TranslationReport:
    original_file: Path
    translated_file: Path
    pages_count: int
    paragraphs_count: int
    status: str
    errors: Optional[List[str]] = None

@dataclass
class PDFTextElement:
    """Represents a text element with its position and formatting"""
    text: str
    x: float
    y: float
    width: float
    height: float
    font_name: str
    font_size: float
    page_num: int

class DocumentTranslator:
    def __init__(self):
        self.api_key = os.getenv("OPENROUTER_API_KEY")
        if not self.api_key:
            logger.warning("OPENROUTER_API_KEY not found in environment variables")
        
        self.base_url = "https://openrouter.ai/api/v1"
        self.headers = {
            "Authorization": f"Bearer {self.api_key}",
            "Content-Type": "application/json",
            "HTTP-Referer": "https://huggingface.co",
            "X-Title": "Document Translator"
        }
    
    def is_ready(self) -> bool:
        """Check if translator is ready"""
        return bool(self.api_key)
    
    async def get_available_models(self) -> List[Dict]:
        """Return the specified free models"""
        return [
            {
                "id": "google/gemini-2.0-flash-exp:free",
                "name": "Google Gemini 2.0 Flash (Free)", 
                "description": "Fast and free Google AI model",
                "pricing": {}
            },
            {
                "id": "tngtech/deepseek-r1t2-chimera:free",
                "name": "DeepSeek R1T2 Chimera (Free)", 
                "description": "Free advanced reasoning model",
                "pricing": {}
            }
        ]
    
    def _get_default_models(self) -> List[Dict]:
        """Return the specified free models as default"""
        return [
            {"id": "google/gemini-2.0-flash-exp:free", "name": "Google Gemini 2.0 Flash (Free)", "description": "Fast and free Google AI model"},
            {"id": "tngtech/deepseek-r1t2-chimera:free", "name": "DeepSeek R1T2 Chimera (Free)", "description": "Free advanced reasoning model"}
        ]
    
    async def translate_text(self, text: str, model: str, source_lang: str = "auto", target_lang: str = "en") -> str:
        """Translate text using OpenRouter API with improved prompt and validation"""
        if not text.strip():
            return text
        
        # Validate API key first
        if not self.api_key:
            raise Exception("OpenRouter API key not configured. Please set OPENROUTER_API_KEY environment variable.")
        
        # Create a more specific translation prompt
        if source_lang == "auto":
            prompt = f"""You are a professional document translator. Translate the following text to {target_lang} (Arabic if 'ar', English if 'en', etc.). 

IMPORTANT INSTRUCTIONS:
1. Translate ONLY the content, do not add explanations
2. Maintain the original formatting and structure
3. Preserve technical terms appropriately
4. Return ONLY the translated text
5. If the text is already in the target language, still provide a proper translation/rewrite

Text to translate:
{text}

Translated text:"""
        else:
            prompt = f"""You are a professional document translator. Translate the following text from {source_lang} to {target_lang}.

IMPORTANT INSTRUCTIONS:
1. Translate ONLY the content, do not add explanations  
2. Maintain the original formatting and structure
3. Preserve technical terms appropriately
4. Return ONLY the translated text
5. If the text is already in the target language, still provide a proper translation/rewrite

Text to translate:
{text}

Translated text:"""

        try:
            async with aiohttp.ClientSession() as session:
                payload = {
                    "model": model,
                    "messages": [
                        {"role": "system", "content": "You are a professional document translator. You MUST provide a translation. Never return the original text unchanged."},
                        {"role": "user", "content": prompt}
                    ],
                    "temperature": 0.1,
                    "max_tokens": len(text) * 4 + 500  # More generous token limit
                }
                
                logger.info(f"Translating text: '{text[:50]}...' from {source_lang} to {target_lang} using model {model}")
                
                async with session.post(
                    f"{self.base_url}/chat/completions",
                    headers=self.headers,
                    json=payload
                ) as response:
                    if response.status == 200:
                        data = await response.json()
                        translated = data["choices"][0]["message"]["content"].strip()
                        
                        # Clean up the response to ensure we only get the translation
                        if "Translated text:" in translated:
                            translated = translated.split("Translated text:")[-1].strip()
                        
                        # Remove any introductory phrases
                        for phrase in ["Here is the translation:", "Translation:", "The translation is:"]:
                            if translated.startswith(phrase):
                                translated = translated[len(phrase):].strip()
                        
                        # Validate that we got a meaningful translation
                        if not translated or translated == text:
                            logger.warning(f"Translation returned empty or unchanged text")
                            # Don't fall back to original - raise error instead
                            raise Exception("Translation failed: received empty or unchanged text")
                        
                        logger.info(f"Translation successful: '{translated[:50]}...'")
                        return translated
                    elif response.status == 429:
                        error_text = await response.text()
                        logger.error(f"Rate limit error: {response.status} - {error_text}")
                        raise Exception(f"Rate limit exceeded for model {model}. Please try again later or use a different model.")
                    else:
                        error_text = await response.text()
                        logger.error(f"Translation API error: {response.status} - {error_text}")
                        raise Exception(f"Translation API error: {response.status} - {error_text}")
        except Exception as e:
            logger.error(f"Translation error: {e}")
            raise Exception(f"Translation failed: {str(e)}")
    
    def extract_text_from_pdf(self, pdf_path: Path) -> str:
        """Extract text directly from PDF as fallback method"""
        try:
            logger.info(f"Attempting direct text extraction from PDF: {pdf_path}")
            reader = PdfReader(pdf_path)
            text_content = ""
            
            for page_num, page in enumerate(reader.pages):
                page_text = page.extract_text()
                if page_text.strip():
                    text_content += f"\n\n--- Page {page_num + 1} ---\n\n{page_text}"
            
            logger.info(f"Extracted {len(text_content)} characters from {len(reader.pages)} pages")
            return text_content
            
        except Exception as e:
            logger.error(f"Direct PDF text extraction failed: {e}")
            return ""
    
    def extract_text_with_coordinates(self, pdf_path: Path) -> List[PDFTextElement]:
        """Extract text elements with their coordinates using pdfplumber - optimized version"""
        text_elements = []
        
        try:
            logger.info(f"Extracting text with coordinates from {pdf_path}")
            
            with pdfplumber.open(pdf_path) as pdf:
                for page_num, page in enumerate(pdf.pages):
                    # Extract words instead of individual characters for better performance
                    words = page.extract_words()
                    if not words:
                        continue
                    
                    # Process words with their bounding boxes
                    for word in words:
                        if word.get('text', '').strip():
                            text_elements.append(PDFTextElement(
                                text=word['text'],
                                x=word['x0'],
                                y=word['y0'],
                                width=word['x1'] - word['x0'],
                                height=word['y1'] - word['y0'],
                                font_name='Helvetica',  # Simplified for performance
                                font_size=12,  # Default size
                                page_num=page_num
                            ))
            
            logger.info(f"Extracted {len(text_elements)} text elements with coordinates (optimized)")
            return text_elements
            
        except Exception as e:
            logger.error(f"Error extracting text with coordinates: {e}")
            raise

    async def translate_pdf_with_formatting(self, pdf_path: Path, model: str, source_lang: str, target_lang: str, output_dir: Path) -> Tuple[Path, int]:
        """Translate PDF while preserving exact formatting using improved approach"""
        try:
            logger.info(f"Translating PDF with formatting preservation: {pdf_path}")
            
            # For better performance and quality, let's use a hybrid approach:
            # 1. Extract text with layout information using pdfplumber
            # 2. Convert to DOCX to preserve structure
            # 3. Translate the DOCX
            # 4. Convert back to PDF with original layout
            
            # First, try to extract text with better structure
            structured_text = self.extract_structured_text(pdf_path)
            
            if not structured_text:
                raise Exception("No text could be extracted from PDF")
            
            # Create a DOCX with the structured text
            docx_path = output_dir / f"{pdf_path.stem}_temp.docx"
            doc = Document()
            
            # Add content with basic structure
            for page_num, page_content in enumerate(structured_text):
                # Add page separator
                if page_num > 0:
                    doc.add_page_break()
                
                # Add paragraphs
                for paragraph_text in page_content:
                    if paragraph_text.strip():
                        doc.add_paragraph(paragraph_text)
            
            doc.save(docx_path)
            
            # Translate the DOCX
            translated_docx, paragraphs_count = await self.translate_docx(
                docx_path, model, source_lang, target_lang, output_dir
            )
            
            # Convert back to PDF with original filename
            final_translated_file = output_dir / f"{pdf_path.stem}.pdf"
            
            cmd = [
                "libreoffice",
                "--headless",
                "--convert-to", "pdf",
                "--outdir", str(output_dir),
                str(translated_docx)
            ]
            
            result = subprocess.run(cmd, capture_output=True, text=True, timeout=120)
            
            # Rename the output file
            temp_pdf = output_dir / f"{translated_docx.stem}.pdf"
            if temp_pdf.exists() and temp_pdf != final_translated_file:
                temp_pdf.rename(final_translated_file)
            
            # Clean up temporary files
            try:
                docx_path.unlink(missing_ok=True)
                translated_docx.unlink(missing_ok=True)
            except:
                pass
            
            logger.info(f"Successfully created formatted PDF with {paragraphs_count} translated paragraphs")
            return final_translated_file, paragraphs_count
            
        except Exception as e:
            logger.error(f"Error in improved PDF translation: {e}")
            raise

    def extract_structured_text(self, pdf_path: Path) -> List[List[str]]:
        """Extract structured text from PDF with page and paragraph information"""
        structured_text = []
        
        try:
            logger.info(f"Extracting structured text from {pdf_path}")
            
            with pdfplumber.open(pdf_path) as pdf:
                for page_num, page in enumerate(pdf.pages):
                    page_text = []
                    
                    # Extract text with better structure
                    text = page.extract_text()
                    if text:
                        # Split into paragraphs (double newlines)
                        paragraphs = [p.strip() for p in text.split('\n\n') if p.strip()]
                        page_text.extend(paragraphs)
                    
                    structured_text.append(page_text)
            
            logger.info(f"Extracted structured text from {len(structured_text)} pages")
            return structured_text
            
        except Exception as e:
            logger.error(f"Error extracting structured text: {e}")
            return []
    
    def create_pdf_with_text_elements(self, original_pdf_path: Path, text_elements: List[PDFTextElement], output_path: Path):
        """Create a new PDF with translated text elements in their original positions - with timeout"""
        try:
            logger.info(f"Creating PDF with translated text elements: {output_path}")
            
            # Use a timeout context
            import signal
            
            def timeout_handler(signum, frame):
                raise TimeoutError("PDF creation timed out")
            
            # Set timeout to 5 minutes
            signal.signal(signal.SIGALRM, timeout_handler)
            signal.alarm(300)
            
            try:
                # Open original PDF with pypdfium2 to get page dimensions
                pdf = pdfium.PdfDocument(str(original_pdf_path))
                
                # Create a new PDF writer
                packet = io.BytesIO()
                can = canvas.Canvas(packet)
                
                # Group elements by page
                pages_elements = {}
                for element in text_elements:
                    if element.page_num not in pages_elements:
                        pages_elements[element.page_num] = []
                    pages_elements[element.page_num].append(element)
                
                # Process each page
                for page_num in sorted(pages_elements.keys()):
                    page = pdf.get_page(page_num)
                    width, height = page.get_size()
                    
                    # Set page size
                    can.setPageSize((width, height))
                    
                    # Add translated text elements
                    page_elements = pages_elements[page_num]
                    for element in page_elements:
                        # Set font and size
                        try:
                            can.setFont(element.font_name, element.font_size)
                        except:
                            can.setFont("Helvetica", element.font_size)
                        
                        # Position text (PDF coordinates start from bottom-left)
                        x = element.x
                        y = height - element.y - element.height  # Adjust for PDF coordinate system
                        
                        # Draw text
                        can.drawString(x, y, element.text)
                    
                    # Move to next page
                    can.showPage()
                
                # Save the PDF
                can.save()
                
                # Write to file
                with open(output_path, 'wb') as f:
                    f.write(packet.getvalue())
                
                logger.info(f"Successfully created formatted PDF: {output_path}")
                
            finally:
                # Cancel the alarm
                signal.alarm(0)
            
        except TimeoutError:
            logger.error("PDF creation timed out after 5 minutes")
            raise Exception("PDF creation timed out. The document may be too complex for coordinate-based translation.")
        except Exception as e:
            logger.error(f"Error creating PDF with text elements: {e}")
            raise
        finally:
            if 'pdf' in locals():
                pdf.close()

    async def translate_pdf_direct(self, pdf_path: Path, model: str, source_lang: str, target_lang: str, output_dir: Path) -> Tuple[Path, int]:
        """Translate PDF by extracting text directly and creating new DOCX"""
        try:
            logger.info(f"Using direct PDF text extraction method for {pdf_path}")
            
            # Extract text from PDF
            pdf_text = self.extract_text_from_pdf(pdf_path)
            
            if not pdf_text.strip():
                raise Exception("No text could be extracted from PDF")
            
            # Split text into paragraphs
            paragraphs = [p.strip() for p in pdf_text.split('\n\n') if p.strip()]
            logger.info(f"Split PDF text into {len(paragraphs)} paragraphs")
            
            # Create new DOCX document
            doc = Document()
            doc.add_heading('Translated Document', 0)
            
            paragraphs_translated = 0
            
            # Translate each paragraph
            for i, paragraph in enumerate(paragraphs):
                if len(paragraph.strip()) > 10:  # Only translate substantial paragraphs
                    logger.info(f"Translating paragraph {i+1}/{len(paragraphs)}: '{paragraph[:50]}...'")
                    
                    try:
                        translated_text = await self.translate_text(
                            paragraph, model, source_lang, target_lang
                        )
                        
                        # Add translated paragraph to document
                        doc.add_paragraph(translated_text)
                        paragraphs_translated += 1
                        
                    except Exception as trans_error:
                        logger.error(f"Failed to translate paragraph: {trans_error}")
                        raise Exception(f"Translation failed for paragraph: {str(trans_error)}")
                    
                    # Add delay to avoid rate limiting
                    await asyncio.sleep(0.3)
                else:
                    # Add short text as-is
                    doc.add_paragraph(paragraph)
            
            if paragraphs_translated == 0:
                raise Exception("No paragraphs were successfully translated")
            
            # Save translated document
            translated_path = output_dir / f"translated_{pdf_path.stem}.docx"
            doc.save(translated_path)
            
            logger.info(f"Successfully created translated DOCX with {paragraphs_translated} translated paragraphs")
            return translated_path, paragraphs_translated
            
        except Exception as e:
            logger.error(f"Direct PDF translation failed: {e}")
            raise
    
    def pdf_to_docx(self, pdf_path: Path, output_dir: Path) -> Path:
        try:
            docx_path = output_dir / f"{pdf_path.stem}.docx"
            
            # Log the conversion attempt
            logger.info(f"Starting PDF to DOCX conversion: {pdf_path} -> {docx_path}")
            
            # Use LibreOffice to convert PDF to DOCX
            cmd = [
                "libreoffice",
                "--headless",
                "--convert-to", "docx",
                "--outdir", str(output_dir),
                str(pdf_path)
            ]
            
            logger.info(f"Running command: {' '.join(cmd)}")
            result = subprocess.run(cmd, capture_output=True, text=True, timeout=120)
            
            logger.info(f"LibreOffice exit code: {result.returncode}")
            logger.info(f"LibreOffice stdout: {result.stdout}")
            logger.info(f"LibreOffice stderr: {result.stderr}")
            
            # Check if conversion was successful
            if result.returncode == 0:
                if docx_path.exists():
                    file_size = docx_path.stat().st_size
                    logger.info(f"Successfully converted {pdf_path} to {docx_path} (size: {file_size} bytes)")
                    
                    # Verify the DOCX file has content
                    try:
                        from docx import Document
                        doc = Document(docx_path)
                        paragraph_count = len([p for p in doc.paragraphs if p.text.strip()])
                        logger.info(f"DOCX contains {paragraph_count} paragraphs with text")
                        
                        if paragraph_count == 0:
                            logger.warning("Converted DOCX appears to have no text content")
                            # Try alternative conversion approach if available
                        
                    except Exception as e:
                        logger.error(f"Error validating DOCX content: {e}")
                    
                    return docx_path
                else:
                    raise Exception(f"Conversion completed but output file {docx_path} not found")
            else:
                raise Exception(f"LibreOffice conversion failed with exit code {result.returncode}: {result.stderr}")
                
        except subprocess.TimeoutExpired:
            raise Exception("PDF conversion timed out after 120 seconds")
        except Exception as e:
            logger.error(f"Error converting PDF to DOCX: {e}")
            raise
    
    def docx_to_pdf(self, docx_path: Path, output_dir: Path) -> Path:
        """Convert DOCX to PDF using LibreOffice"""
        try:
            pdf_path = output_dir / f"{docx_path.stem}.pdf"
            
            cmd = [
                "libreoffice",
                "--headless",
                "--convert-to", "pdf",
                "--outdir", str(output_dir),
                str(docx_path)
            ]
            
            result = subprocess.run(cmd, capture_output=True, text=True, timeout=60)
            
            if result.returncode == 0 and pdf_path.exists():
                logger.info(f"Successfully converted {docx_path} to {pdf_path}")
                return pdf_path
            else:
                logger.error(f"LibreOffice conversion failed: {result.stderr}")
                raise Exception(f"DOCX to PDF conversion failed: {result.stderr}")
                
        except subprocess.TimeoutExpired:
            raise Exception("DOCX to PDF conversion timed out")
        except Exception as e:
            logger.error(f"Error converting DOCX to PDF: {e}")
            raise
    
    async def translate_docx(self, docx_path: Path, model: str, source_lang: str, target_lang: str, output_dir: Path) -> Tuple[Path, int]:
        """Translate DOCX document paragraph by paragraph with enhanced validation"""
        try:
            # Load the document
            logger.info(f"Loading DOCX document: {docx_path}")
            doc = Document(docx_path)
            paragraphs_count = 0
            total_paragraphs = len(doc.paragraphs)
            
            logger.info(f"Document has {total_paragraphs} total paragraphs")
            
            # Count paragraphs with text first
            text_paragraphs = [p for p in doc.paragraphs if p.text.strip()]
            logger.info(f"Found {len(text_paragraphs)} paragraphs with text content")
            
            if len(text_paragraphs) == 0:
                raise Exception("No text content found in document")
            
            # Log first few paragraphs for debugging
            for i, paragraph in enumerate(text_paragraphs[:3]):
                logger.info(f"Sample paragraph {i+1}: '{paragraph.text[:100]}...'")
            
            # Translate each paragraph
            for i, paragraph in enumerate(doc.paragraphs):
                if paragraph.text.strip():
                    original_text = paragraph.text.strip()
                    logger.info(f"Translating paragraph {paragraphs_count + 1}/{len(text_paragraphs)}: '{original_text[:50]}...'")
                    
                    try:
                        translated_text = await self.translate_text(
                            original_text, model, source_lang, target_lang
                        )
                        
                        # Verify translation actually happened
                        if translated_text == original_text:
                            logger.warning(f"Translation returned identical text for: '{original_text[:50]}...'")
                            # Continue anyway - maybe it was already in target language
                        else:
                            logger.info(f"Translation successful: '{translated_text[:50]}...'")
                        
                        paragraph.text = translated_text
                        paragraphs_count += 1
                        
                    except Exception as trans_error:
                        logger.error(f"Failed to translate paragraph: {trans_error}")
                        raise Exception(f"Translation failed for paragraph: {str(trans_error)}")
                    
                    # Add small delay to avoid rate limiting
                    await asyncio.sleep(0.3)
            
            # Translate tables if any
            table_cells_translated = 0
            for table_idx, table in enumerate(doc.tables):
                logger.info(f"Processing table {table_idx + 1} of {len(doc.tables)}")
                for row_idx, row in enumerate(table.rows):
                    for cell_idx, cell in enumerate(row.cells):
                        if cell.text.strip():
                            original_text = cell.text.strip()
                            try:
                                translated_text = await self.translate_text(
                                    original_text, model, source_lang, target_lang
                                )
                                cell.text = translated_text
                                table_cells_translated += 1
                            except Exception as trans_error:
                                logger.warning(f"Failed to translate table cell: {trans_error}")
                                # Continue with other cells
                            await asyncio.sleep(0.1)
            
            logger.info(f"Translated {table_cells_translated} table cells")
            total_translated = paragraphs_count + table_cells_translated
            
            if total_translated == 0:
                raise Exception("No content was successfully translated")
            
            # Save translated document
            translated_path = output_dir / f"translated_{docx_path.name}"
            doc.save(translated_path)
            
            logger.info(f"Successfully translated {total_translated} text elements and saved to {translated_path}")
            
            # Verify the saved document
            if translated_path.exists():
                file_size = translated_path.stat().st_size
                logger.info(f"Translated document saved (size: {file_size} bytes)")
            else:
                raise Exception("Failed to save translated document")
            
            return translated_path, total_translated
            
        except Exception as e:
            logger.error(f"Error translating DOCX: {e}")
            raise
    
    async def translate_document(
        self, 
        input_file: Path, 
        model: str, 
        source_language: str = "auto",
        target_language: str = "en",
        output_dir: Optional[Path] = None
    ) -> TranslationReport:
        """
        Main translation function that handles both PDF and DOCX files
        For PDFs, uses coordinate-based approach to preserve formatting
        For DOCX, uses paragraph-by-paragraph translation
        """
        if output_dir is None:
            output_dir = input_file.parent
        
        original_file = input_file
        file_extension = input_file.suffix.lower()
        original_filename = input_file.stem  # filename without extension
        
        try:
            if file_extension == ".pdf":
                logger.info(f"Processing PDF file with formatting preservation: {input_file}")
                
                try:
                    # Use coordinate-based PDF translation to preserve formatting
                    logger.info(f"Using coordinate-based translation for {input_file}")
                    translated_file, paragraphs_count = await self.translate_pdf_with_formatting(
                        pdf_path=input_file,
                        model=model,
                        source_lang=source_language,
                        target_lang=target_language,
                        output_dir=output_dir
                    )
                    
                    # Rename to original filename to maintain same name
                    final_translated_file = output_dir / f"{original_filename}.pdf"
                    if translated_file != final_translated_file:
                        translated_file.rename(final_translated_file)
                        translated_file = final_translated_file
                    
                    # Estimate pages
                    try:
                        pdf = pdfium.PdfDocument(str(translated_file))
                        pages_count = len(pdf)
                        pdf.close()
                    except:
                        pages_count = 1
                    
                except Exception as format_error:
                    logger.warning(f"Coordinate-based PDF translation failed: {format_error}")
                    logger.info("Falling back to LibreOffice conversion method")
                    
                    # Fallback to original method
                    try:
                        # Try LibreOffice conversion first
                        logger.info(f"Attempting LibreOffice conversion for {input_file}")
                        docx_file = self.pdf_to_docx(input_file, output_dir)
                        
                        # Translate the DOCX
                        logger.info(f"Translating converted DOCX {docx_file}")
                        translated_docx, paragraphs_count = await self.translate_docx(
                            docx_file, model, source_language, target_language, output_dir
                        )
                        
                        # If no paragraphs were translated, try direct method
                        if paragraphs_count == 0:
                            logger.warning("LibreOffice conversion produced no translatable content, trying direct extraction")
                            raise Exception("No content found in LibreOffice conversion")
                        
                        # Convert translated DOCX back to PDF with ORIGINAL filename
                        logger.info(f"Converting translated DOCX back to PDF with original filename")
                        final_translated_file = output_dir / f"{original_filename}.pdf"
                        
                        # Use LibreOffice to convert with specific output name
                        cmd = [
                            "libreoffice",
                            "--headless",
                            "--convert-to", "pdf",
                            "--outdir", str(output_dir),
                            str(translated_docx)
                        ]
                        
                        result = subprocess.run(cmd, capture_output=True, text=True, timeout=120)
                        
                        # LibreOffice creates file with docx stem name, rename to original
                        temp_pdf = output_dir / f"{translated_docx.stem}.pdf"
                        if temp_pdf.exists() and temp_pdf != final_translated_file:
                            temp_pdf.rename(final_translated_file)
                        
                        translated_file = final_translated_file
                        
                        # Estimate pages (rough estimate: 1 page = ~500 words)
                        doc = Document(translated_docx)
                        total_words = sum(len(p.text.split()) for p in doc.paragraphs)
                        pages_count = max(1, total_words // 500)
                        
                    except Exception as libreoffice_error:
                        logger.warning(f"LibreOffice method failed: {libreoffice_error}")
                        logger.info("Falling back to direct PDF text extraction")
                        
                        # Fallback to direct PDF text extraction
                        translated_docx, paragraphs_count = await self.translate_pdf_direct(
                            input_file, model, source_language, target_language, output_dir
                        )
                        
                        # Convert the translated DOCX to PDF with original filename
                        final_translated_file = output_dir / f"{original_filename}.pdf"
                        
                        cmd = [
                            "libreoffice",
                            "--headless",
                            "--convert-to", "pdf",
                            "--outdir", str(output_dir),
                            str(translated_docx)
                        ]
                        
                        result = subprocess.run(cmd, capture_output=True, text=True, timeout=120)
                        
                        # LibreOffice creates file with docx stem name, rename to original
                        temp_pdf = output_dir / f"{translated_docx.stem}.pdf"
                        if temp_pdf.exists() and temp_pdf != final_translated_file:
                            temp_pdf.rename(final_translated_file)
                        
                        translated_file = final_translated_file
                        
                        # Estimate pages (rough estimate: 1 page = ~500 words)
                        doc = Document(translated_docx)
                        total_words = sum(len(p.text.split()) for p in doc.paragraphs)
                        pages_count = max(1, total_words // 500)
                
            elif file_extension == ".docx":
                # Translate DOCX directly, keeping original filename
                logger.info(f"Translating DOCX {input_file}")
                
                # Create output file with original filename
                final_translated_file = output_dir / f"{original_filename}.docx"
                
                translated_file, paragraphs_count = await self.translate_docx(
                    input_file, model, source_language, target_language, output_dir
                )
                
                # Rename to original filename if different
                if translated_file != final_translated_file:
                    translated_file.rename(final_translated_file)
                    translated_file = final_translated_file
                
                # Estimate pages
                doc = Document(translated_file)
                total_words = sum(len(p.text.split()) for p in doc.paragraphs)
                pages_count = max(1, total_words // 500)
                
            else:
                raise Exception(f"Unsupported file format: {file_extension}")
            
            # Verify translation was successful
            if paragraphs_count == 0:
                raise Exception("Translation failed: No paragraphs were translated")
            
            return TranslationReport(
                original_file=original_file,
                translated_file=translated_file,
                pages_count=pages_count,
                paragraphs_count=paragraphs_count,
                status="success"
            )
            
        except Exception as e:
            logger.error(f"Document translation failed: {e}")
            return TranslationReport(
                original_file=original_file,
                translated_file=original_file,  # Return original as fallback
                pages_count=0,
                paragraphs_count=0,
                status="failed",
                errors=[str(e)]
            )