from io import BytesIO
from tempfile import NamedTemporaryFile
from unittest.mock import Mock

import fitz
import pytest
from pptx import Presentation

from src.backend.utils import pdf


class TestConvertPPTXToPDF:
    @pytest.fixture
    def mock_pptx_bytes(self) -> BytesIO:
        """Create a new mock PPTX presentation with a single slide."""
        presentation = Presentation()
        slide_layout = presentation.slide_layouts[0]
        slide = presentation.slides.add_slide(slide_layout)

        title = slide.shapes.title
        subtitle = slide.placeholders[1]

        title.text = "Hello, World!"
        subtitle.text = (
            "This is a new PowerPoint presentation created with python-pptx."
        )

        pptx_bytes = BytesIO()
        presentation.save(pptx_bytes)

        pptx_bytes.seek(0)

        return pptx_bytes

    @pytest.mark.asyncio
    async def test_convert_pptx_to_pdf(self, mock_pptx_bytes):
        result = await pdf.convert_pptx_to_pdf(mock_pptx_bytes)
        assert isinstance(result, BytesIO)


class TestAdjustPDFFile:
    @pytest.fixture
    def mock_pdf_bytes(self) -> BytesIO:
        """Create a new mock PDF document with a single blank page."""
        pdf_document = fitz.open()
        pdf_document.new_page(width=595, height=842)
        pdf_bytes = BytesIO()
        pdf_document.save(pdf_bytes)
        pdf_document.close()
        pdf_bytes.seek(0)
        return pdf_bytes

    def test_adjust_pdf_file(self, mock_pdf_bytes):
        result = pdf.adjust_pdf_file(mock_pdf_bytes, new_exif_title="mock title")
        assert isinstance(result, BytesIO)


class TestCheckPDFConversionSuccess:
    def test_check_pdf_conversion_success_bad_return_code(self):
        with pytest.raises(ValueError):
            pdf._check_pdf_conversion_success(1, Mock(), "mock")

    def test_check_pdf_conversion_success_path_not_exists(self):
        with pytest.raises(RuntimeError):
            pdf._check_pdf_conversion_success(0, Mock(), "this_path_does_not_exist")

    def test_check_pdf_conversion_success_path_size_is_0(self):
        with NamedTemporaryFile() as temp_file:
            with pytest.raises(RuntimeError):
                pdf._check_pdf_conversion_success(0, Mock(), temp_file.name)