# utils/validation.py - File validation for PDF Analysis & Orchestrator
import os
from pathlib import Path

MAX_MB = int(os.environ.get("ANALYSIS_MAX_UPLOAD_MB", 50))

def _get_size_bytes_from_uploaded(uploaded) -> int:
    """
    Get file size from uploaded file object
    uploaded may be a path (str), file-like object, or dict {'name': path}
    """
    try:
        if isinstance(uploaded, str) and os.path.exists(uploaded):
            return Path(uploaded).stat().st_size
        if isinstance(uploaded, dict) and "name" in uploaded and os.path.exists(uploaded["name"]):
            return Path(uploaded["name"]).stat().st_size
        if hasattr(uploaded, "seek") and hasattr(uploaded, "tell"):
            current = uploaded.tell()
            uploaded.seek(0, 2)
            size = uploaded.tell()
            uploaded.seek(current)
            return size
    except Exception:
        pass
    # Unknown size -> be conservative and allow it (or raise)
    return 0

def validate_file_size(uploaded):
    """Validate uploaded file size"""
    size_bytes = _get_size_bytes_from_uploaded(uploaded)
    if size_bytes == 0:
        # If unknown, skip (or you could raise). We'll allow but log in production.
        return True
    mb = size_bytes / (1024 * 1024)
    if mb > MAX_MB:
        raise ValueError(f"Uploaded file exceeds allowed size of {MAX_MB} MB (size: {mb:.2f} MB).")
    return True