import base64

import pytest
from fastapi import HTTPException

from openocr_markdown.openai_schemas import ChatMessage, ChatMessageContentImageUrl, ChatMessageContentPart
from openocr_markdown.openai_utils import DATA_URL_PATTERN, extract_image_urls, materialize_image_url


def test_extract_image_urls_from_multimodal_message() -> None:
    messages = [
        ChatMessage(
            role="user",
            content=[
                ChatMessageContentPart(type="text", text="Convert to markdown"),
                ChatMessageContentPart(
                    type="image_url",
                    image_url=ChatMessageContentImageUrl(url="https://example.com/page.png"),
                ),
            ],
        )
    ]
    assert extract_image_urls(messages) == ["https://example.com/page.png"]


def test_materialize_data_url(tmp_path) -> None:
    png_bytes = base64.b64decode(
        "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg=="
    )
    data_url = "data:image/png;base64," + base64.b64encode(png_bytes).decode()
    path = materialize_image_url(data_url, tmp_path)
    assert path.exists()
    assert path.suffix == ".png"


def test_data_url_pattern_rejects_invalid_input() -> None:
    assert DATA_URL_PATTERN.match("not-a-data-url") is None


def test_materialize_image_url_rejects_unsupported_scheme(tmp_path) -> None:
    with pytest.raises(HTTPException) as exc:
        materialize_image_url("ftp://example.com/a.png", tmp_path)
    assert exc.value.status_code == 400