# FILE: resource_processor.py

import io
import PyPDF2
import docx
import logging
from typing import Optional, Dict, List, Any
import os

logger = logging.getLogger(__name__)

def _extract_text_from_pdf_bytes(file_bytes: bytes, filename: str) -> Optional[str]:
    # (Your full PDF extraction logic here)
    try:
        pdf_file = io.BytesIO(file_bytes)
        reader = PyPDF2.PdfReader(pdf_file)
        text = "\n".join(page.extract_text() for page in reader.pages if page.extract_text())
        return text.strip() or None
    except Exception as e:
        logger.error(f"Error extracting PDF '{filename}': {e}")
        return None
def _extract_text_from_docx_bytes(file_bytes: bytes, filename: str) -> Optional[str]:
    try:
        doc_file = io.BytesIO(file_bytes)
        document = docx.Document(doc_file)
        text = "\n".join([para.text for para in document.paragraphs if para.text.strip()])
        full_text = text.strip()
        logger.info(f"Successfully extracted text from DOCX '{filename}'. Length: {len(full_text)} chars.")
        return full_text if full_text else None
    except Exception as e:
        logger.error(f"Error extracting text from DOCX '{filename}': {e}", exc_info=True)
        return None

def _extract_text_from_txt_bytes(file_bytes: bytes, filename: str) -> Optional[str]:
    try:
        text = file_bytes.decode('utf-8')
    except UnicodeDecodeError:
        try:
            logger.warning(f"UTF-8 decoding failed for '{filename}', trying latin-1.")
            text = file_bytes.decode('latin-1')
        except UnicodeDecodeError:
            logger.error(f"Could not decode TXT file '{filename}' with UTF-8 or latin-1.")
            return None
        except Exception as e_latin1:
             logger.error(f"Error decoding TXT file '{filename}' with latin-1: {e_latin1}")
             return None
    except Exception as e:
        logger.error(f"Error reading TXT file '{filename}': {e}", exc_info=True)
        return None
    
    full_text = text.strip()
    logger.info(f"Successfully read text from TXT '{filename}'. Length: {len(full_text)} chars.")
    return full_text if full_text else None


def process_uploaded_files(uploaded_files: Optional[List[Any]]) -> Optional[Dict[str, str]]:
    if not uploaded_files:
        return None
    print("Processing Here")
    extracted_texts = {}
    for uploaded_file in uploaded_files:
        filename = uploaded_file.name
        # In Gradio, .name is the path to a temporary file
        with open(filename, 'rb') as f:
            content_bytes = f.read()
        
        text_content = None
        if filename.lower().endswith('.pdf'):
            text_content = _extract_text_from_pdf_bytes(content_bytes, filename)
        elif filename.lower().endswith('.docx'):
            text_content = _extract_text_from_docx_bytes(content_bytes, filename)
        elif filename.lower().endswith('.txt'):
            text_content = _extract_text_from_txt_bytes(content_bytes, filename)
        
        if text_content:
            # We use the original filename (basename) as the key
            original_filename = os.path.basename(filename)
            extracted_texts[original_filename] = text_content

        print("Processing Done")
            
    return extracted_texts if extracted_texts else None