"""Parser registry — dispatch by file extension."""

import os
from parsers.pdf_parser import parse_pdf
from parsers.word_parser import parse_word
from parsers.excel_parser import parse_excel, parse_excel_to_chunks
from parsers.cad_parser import parse_cad
from parsers.gis_parser import parse_gis


EXTENSION_MAP = {
    ".pdf": "pdf",
    ".docx": "word",
    ".xlsx": "excel",
    ".xls": "excel",
    ".dwg": "cad",
    ".dxf": "cad",
    ".shp": "gis",
    ".geojson": "gis",
    ".json": "gis",
    ".kml": "gis",
    ".gpkg": "gis",
}

SUPPORTED_EXTENSIONS = set(EXTENSION_MAP.keys())


def detect_file_type(file_path: str) -> str:
    ext = os.path.splitext(file_path)[1].lower()
    return EXTENSION_MAP.get(ext, "unknown")


def parse_file(file_path: str, extract_images: bool = False) -> dict:
    """Parse a file and return {'markdown': str, 'images': list, 'error': str}."""
    ftype = detect_file_type(file_path)

    if ftype == "pdf":
        return parse_pdf(file_path, extract_images=extract_images)
    elif ftype == "word":
        return parse_word(file_path, extract_images=extract_images)
    elif ftype == "excel":
        return parse_excel(file_path)
    elif ftype == "cad":
        return parse_cad(file_path)
    elif ftype == "gis":
        return parse_gis(file_path)
    else:
        return {"markdown": "", "error": f"不支持的文件类型: {os.path.splitext(file_path)[1]}"}


def categorize_file(file_type: str) -> str:
    return {
        "pdf": "文档", "word": "文档", "excel": "数据",
        "cad": "图纸", "gis": "地理",
    }.get(file_type, "其他")


def get_file_size(file_path: str) -> str:
    try:
        size = os.path.getsize(file_path)
        if size < 1024:
            return f"{size} B"
        elif size < 1024 * 1024:
            return f"{size / 1024:.1f} KB"
        else:
            return f"{size / (1024 * 1024):.1f} MB"
    except OSError:
        return "0 B"