import io
import os
from typing import Literal

import fitz
from PIL import Image


def determine_file_type(file_path: str) -> str:
    import os

    _, file_extension = os.path.splitext(file_path)
    if file_extension.lower() in ['.pdf']:
        return 'pdf'
    elif file_extension.lower() in ['.jpg', '.jpeg', '.png', '.bmp', '.gif', '.tiff']:
        return 'image'
    else:
        supported_types = ', '.join(['PDF', 'JPG', 'JPEG', 'PNG', 'BMP', 'GIF', 'TIFF'])
        raise ValueError(
            f"Unsupported file type: {file_extension}. "
            f"Only the following file types are supported: {supported_types}"
        )


def get_bytes_from_path(file_path: str) -> bytes:
    with open(file_path, 'rb') as file:
        file_bytes = file.read()
    return file_bytes


def get_PIL_image_from_path(file_path: str) -> Image.Image:
    image = Image.open(file_path)
    return image


def get_images_from_path(file_path: str) -> list[Image.Image]:
    file_type = determine_file_type(file_path)
    if file_type == 'image':
        return [get_PIL_image_from_path(file_path)]
    elif file_type == 'pdf':
        doc = fitz.open(file_path)

        images = []
        for page_num in range(len(doc)):
            page = doc[page_num]
            pix = page.get_pixmap()
            img_data = pix.tobytes("ppm")
            img = Image.open(io.BytesIO(img_data))
            images.append(img)

        doc.close()
        return images