# -*- coding: utf-8 -*-

import pytest

import camelot.backends.image_conversion
from camelot.backends import ImageConversionBackend
from camelot.backends.poppler_backend import PopplerBackend
from camelot.backends.ghostscript_backend import  GhostscriptBackend


class PopplerBackendError(object):
    def convert(self, pdf_path, png_path):
        raise ValueError('conversion failed')


class GhostscriptBackendError(object):
    def convert(self, pdf_path, png_path):
        raise ValueError('conversion failed')


class GhostscriptBackendNoError(object):
    def convert(self, pdf_path, png_path):
        pass


def test_poppler_backend_error_when_no_use_fallback(monkeypatch):
    backends = {"poppler": PopplerBackendError, "ghostscript": GhostscriptBackendNoError}
    monkeypatch.setattr("camelot.backends.image_conversion.backends", backends, raising=True)
    backend = ImageConversionBackend(use_fallback=False)

    message = "conversion failed with image conversion backend 'poppler'"
    with pytest.raises(ValueError, match=message):
        backend.convert('foo', 'bar')

def test_ghostscript_backend_when_use_fallback(monkeypatch):
    backends = {"poppler": PopplerBackendError, "ghostscript": GhostscriptBackendNoError}
    monkeypatch.setattr("camelot.backends.image_conversion.backends", backends, raising=True)
    backend = ImageConversionBackend()
    backend.convert('foo', 'bar')


def test_ghostscript_backend_error_when_use_fallback(monkeypatch):
    backends = {"poppler": PopplerBackendError, "ghostscript": GhostscriptBackendError}
    monkeypatch.setattr("camelot.backends.image_conversion.backends", backends, raising=True)
    backend = ImageConversionBackend()

    message = "conversion failed with image conversion backend 'ghostscript'"
    with pytest.raises(ValueError, match=message):
        backend.convert('foo', 'bar')