# © 2017 James R. Barlow: github.com/jbarlow83
#
# This file is part of OCRmyPDF.
#
# OCRmyPDF is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# OCRmyPDF is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with OCRmyPDF.  If not, see <http://www.gnu.org/licenses/>.

import ast
import os
import platform
import sys
from pathlib import Path
from subprocess import PIPE, run

import pytest

from ocrmypdf import api, cli, pdfinfo
from ocrmypdf._plugin_manager import get_parser_options_plugins
from ocrmypdf.exec import unpaper

pytest_plugins = ['helpers_namespace']


# pylint: disable=E1101
# pytest.helpers is dynamic so it confuses pylint

if sys.version_info < (3, 5):
    print("Requires Python 3.5+")
    sys.exit(1)


@pytest.helpers.register
def is_linux():
    return platform.system() == 'Linux'


@pytest.helpers.register
def is_macos():
    return platform.system() == 'Darwin'


@pytest.helpers.register
def running_in_docker():
    # Docker creates a file named /.dockerenv (newer versions) or
    # /.dockerinit (older) -- this is undocumented, not an offical test
    return Path('/.dockerenv').exists() or Path('/.dockerinit').exists()


@pytest.helpers.register
def running_in_travis():
    return os.environ.get('TRAVIS') == 'true'


@pytest.helpers.register
def have_unpaper():
    try:
        unpaper.version()
    except Exception:  # pylint: disable=broad-except
        return False
    return True


TESTS_ROOT = Path(__file__).parent.resolve()
PROJECT_ROOT = TESTS_ROOT
OCRMYPDF = [sys.executable, '-m', 'ocrmypdf']


@pytest.fixture
def resources():
    return Path(TESTS_ROOT) / 'resources'


@pytest.fixture
def ocrmypdf_exec():
    return OCRMYPDF


@pytest.fixture(scope="function")
def outdir(tmp_path):
    return tmp_path


@pytest.fixture(scope="function")
def outpdf(tmp_path):
    return tmp_path / 'out.pdf'


@pytest.fixture(scope="function")
def no_outpdf(tmp_path):
    """This just documents the fact that a test is not expected to produce
    output. Unfortunately an assertion failure inside a test fixture produces
    an error rather than a test failure, so no testing is done. It's up to
    the test to confirm that no output file was created."""
    return tmp_path / 'no_output.pdf'


@pytest.helpers.register
def check_ocrmypdf(input_file, output_file, *args):
    """Run ocrmypdf and confirmed that a valid file was created"""
    args = [str(input_file), str(output_file)] + [
        str(arg) for arg in args if arg is not None
    ]

    _parser, options, plugin_manager = get_parser_options_plugins(args=args)
    api.check_options(options, plugin_manager)
    result = api.run_pipeline(options, plugin_manager=plugin_manager, api=True)

    assert result == 0
    assert output_file.exists(), "Output file not created"
    assert output_file.stat().st_size > 100, "PDF too small or empty"

    return output_file


@pytest.helpers.register
def run_ocrmypdf_api(input_file, output_file, *args):
    """Run ocrmypdf via API and let caller deal with results

    Does not currently have a way to manipulate the PATH except for Tesseract.
    """

    args = [str(input_file), str(output_file)] + [
        str(arg) for arg in args if arg is not None
    ]
    _parser, options, plugin_manager = get_parser_options_plugins(args=args)

    api.check_options(options, plugin_manager)
    return api.run_pipeline(options, plugin_manager=None, api=False)


@pytest.helpers.register
def run_ocrmypdf(input_file, output_file, *args, universal_newlines=True):
    "Run ocrmypdf and let caller deal with results"

    p_args = (
        OCRMYPDF
        + [str(arg) for arg in args if arg is not None]
        + [str(input_file), str(output_file)]
    )

    # Tell subprocess where to find coverage.py configuration
    # This has no effect except when coverage is running
    # Details: https://coverage.readthedocs.io/en/coverage-5.0/subprocess.html
    coverage_rc = Path(__file__).parent.parent / '.coveragerc'
    assert coverage_rc.exists()
    env = os.environ.copy()
    env['COVERAGE_PROCESS_START'] = os.fspath(coverage_rc)

    p = run(
        p_args,
        stdout=PIPE,
        stderr=PIPE,
        universal_newlines=universal_newlines,
        env=env,
        check=False,
    )
    # print(p.stderr)
    return p, p.stdout, p.stderr


@pytest.helpers.register
def first_page_dimensions(pdf):
    info = pdfinfo.PdfInfo(pdf)
    page0 = info[0]
    return (page0.width_inches, page0.height_inches)


def pytest_addoption(parser):
    parser.addoption(
        "--runslow",
        action="store_true",
        default=False,
        help=(
            "run slow tests only useful for development (unlikely to be "
            "useful for downstream packagers)"
        ),
    )


def pytest_collection_modifyitems(config, items):
    if config.getoption("--runslow"):
        # --runslow given in cli: do not skip slow tests
        return
    skip_slow = pytest.mark.skip(reason="need --runslow option to run")
    for item in items:
        if "slow" in item.keywords:
            item.add_marker(skip_slow)