import fitz
import base64
import io
from PIL import Image
from typing import List, Dict


MIN_WIDTH  = 50
MIN_HEIGHT = 50


def extract_images_from_pdf(pdf_bytes: bytes) -> List[Dict]:
    if not pdf_bytes:
        return []

    try:
        doc    = fitz.open(stream=pdf_bytes, filetype="pdf")
        images = []
        seen   = set()

        for page_num in range(len(doc)):
            page       = doc[page_num]
            image_list = page.get_images(full=True)

            for img in image_list:
                xref = img[0]
                if xref in seen:
                    continue
                seen.add(xref)

                try:
                    base_image  = doc.extract_image(xref)
                    image_bytes = base_image["image"]
                    image_ext   = base_image["ext"].lower()

                    pil_image = Image.open(io.BytesIO(image_bytes))

                    if pil_image.width < MIN_WIDTH or pil_image.height < MIN_HEIGHT:
                        continue

                    image_b64 = base64.b64encode(image_bytes).decode("utf-8")

                    images.append({
                        "page":   page_num + 1,
                        "format": image_ext,
                        "width":  pil_image.width,
                        "height": pil_image.height,
                        "data":   f"data:image/{image_ext};base64,{image_b64}",
                    })

                except Exception as e:
                    print(f"Failed to extract image xref={xref} page={page_num + 1}: {e}")
                    continue

        doc.close()
        return images

    except Exception as e:
        print(f"Image extraction error: {e}")
        return []


def extract_images_from_image_file(file_bytes: bytes, ext: str) -> List[Dict]:
    try:
        pil_image = Image.open(io.BytesIO(file_bytes))
        image_b64 = base64.b64encode(file_bytes).decode("utf-8")
        return [{
            "page":   1,
            "format": ext,
            "width":  pil_image.width,
            "height": pil_image.height,
            "data":   f"data:image/{ext};base64,{image_b64}",
        }]
    except Exception as e:
        print(f"Image file read error: {e}")
        return []