n0mad1k
83 lines
2.8 KiB
Python
83 lines
2.8 KiB
Python
"""PDF document parser for Mosaic — PyMuPDF text extraction."""
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import logging
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from typing import Optional
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from .base import ParseResult
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logger = logging.getLogger(__name__)
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class PDFDocParser:
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"""Parse PDF documents using PyMuPDF (fitz) for text extraction."""
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def __init__(self, max_pages: int = 200, min_chars_per_page: int = 50):
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self.max_pages = max_pages
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self.min_chars_per_page = min_chars_per_page
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def parse(self, file_path: str) -> ParseResult:
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"""Parse a PDF file.
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Extracts text page by page. Large docs (>max_pages) are split.
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After extraction, checks chars/page ratio for OCR detection.
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"""
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try:
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import fitz # PyMuPDF
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except ImportError:
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return ParseResult(error="PyMuPDF (fitz) not installed")
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try:
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doc = fitz.open(file_path)
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total_pages = len(doc)
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metadata = {
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'page_count': total_pages,
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'format': doc.metadata.get('format', ''),
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'title': doc.metadata.get('title', ''),
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'author': doc.metadata.get('author', ''),
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'subject': doc.metadata.get('subject', ''),
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'creator': doc.metadata.get('creator', ''),
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}
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title = metadata['title'] or ''
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# Limit pages
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pages_to_process = min(total_pages, self.max_pages)
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if total_pages > self.max_pages:
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logger.warning("PDF has %d pages, processing first %d",
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total_pages, self.max_pages)
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metadata['truncated'] = True
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metadata['truncated_at_page'] = self.max_pages
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# Extract text page by page with form feed separators
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text_parts = []
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for page_num in range(pages_to_process):
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page = doc[page_num]
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page_text = page.get_text("text")
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if page_text.strip():
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text_parts.append(page_text.strip())
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doc.close()
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text = '\f'.join(text_parts) # Form feed between pages
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char_count = len(text)
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# Check for OCR need
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needs_ocr = False
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if pages_to_process > 0:
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chars_per_page = char_count / pages_to_process
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if chars_per_page < self.min_chars_per_page:
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needs_ocr = True
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metadata['chars_per_page'] = chars_per_page
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return ParseResult(
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success=True,
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text=text,
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metadata=metadata,
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doc_type='pdf',
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title=title,
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char_count=char_count,
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needs_ocr=needs_ocr,
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)
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except Exception as e:
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return ParseResult(error=f"PDF parse error: {str(e)}")
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