# Pylint doesn't play well with fixtures and dependency injection from pytest
# pylint: disable=redefined-outer-name

import os
import pytest

from buildstream._context import Context
from buildstream._exceptions import LoadError, LoadErrorReason

DATA_DIR = os.path.join(
    os.path.dirname(os.path.realpath(__file__)),
    'context',
)


# Simple fixture to create a Context object.
@pytest.fixture()
def context_fixture():
    if os.environ.get('XDG_CACHE_HOME'):
        cache_home = os.environ['XDG_CACHE_HOME']
    else:
        cache_home = os.path.expanduser('~/.cache')

    return {
        'xdg-cache': cache_home,
        'context': Context()
    }


#######################################
#        Test instantiation           #
#######################################
def test_context_create(context_fixture):
    context = context_fixture['context']
    assert isinstance(context, Context)


#######################################
#     Test configuration loading      #
#######################################
def test_context_load(context_fixture):
    context = context_fixture['context']
    cache_home = os.path.normpath(context_fixture['xdg-cache'])
    assert isinstance(context, Context)

    context.load(config=os.devnull)
    assert context.sourcedir == os.path.join(cache_home, 'buildstream', 'sources')
    assert context.builddir == os.path.join(cache_home, 'buildstream', 'build')
    assert context.cachedir == os.path.join(cache_home, 'buildstream')
    assert context.logdir == os.path.join(cache_home, 'buildstream', 'logs')


# Assert that a changed XDG_CACHE_HOME doesn't cause issues
def test_context_load_envvar(context_fixture):
    os.environ['XDG_CACHE_HOME'] = '/some/path/'

    context = context_fixture['context']
    assert isinstance(context, Context)

    context.load(config=os.devnull)
    assert context.sourcedir == os.path.join('/', 'some', 'path', 'buildstream', 'sources')
    assert context.builddir == os.path.join('/', 'some', 'path', 'buildstream', 'build')
    assert context.cachedir == os.path.join('/', 'some', 'path', 'buildstream')
    assert context.logdir == os.path.join('/', 'some', 'path', 'buildstream', 'logs')

    # Reset the environment variable
    del os.environ['XDG_CACHE_HOME']


# Test that values in a user specified config file
# override the defaults
@pytest.mark.datafiles(os.path.join(DATA_DIR))
def test_context_load_user_config(context_fixture, datafiles):
    context = context_fixture['context']
    cache_home = context_fixture['xdg-cache']
    assert isinstance(context, Context)

    conf_file = os.path.join(datafiles.dirname,
                             datafiles.basename,
                             'userconf.yaml')
    context.load(conf_file)

    assert context.sourcedir == os.path.expanduser('~/pony')
    assert context.builddir == os.path.join(cache_home, 'buildstream', 'build')
    assert context.cachedir == os.path.join(cache_home, 'buildstream')
    assert context.logdir == os.path.join(cache_home, 'buildstream', 'logs')


#######################################
#          Test failure modes         #
#######################################
@pytest.mark.datafiles(os.path.join(DATA_DIR))
def test_context_load_missing_config(context_fixture, datafiles):
    context = context_fixture['context']
    assert isinstance(context, Context)

    conf_file = os.path.join(datafiles.dirname,
                             datafiles.basename,
                             'nonexistant.yaml')

    with pytest.raises(LoadError) as exc:
        context.load(conf_file)

    assert exc.value.reason == LoadErrorReason.MISSING_FILE


@pytest.mark.datafiles(os.path.join(DATA_DIR))
def test_context_load_malformed_config(context_fixture, datafiles):
    context = context_fixture['context']
    assert isinstance(context, Context)

    conf_file = os.path.join(datafiles.dirname,
                             datafiles.basename,
                             'malformed.yaml')

    with pytest.raises(LoadError) as exc:
        context.load(conf_file)

    assert exc.value.reason == LoadErrorReason.INVALID_YAML


@pytest.mark.datafiles(os.path.join(DATA_DIR))
def test_context_load_notdict_config(context_fixture, datafiles):
    context = context_fixture['context']
    assert isinstance(context, Context)

    conf_file = os.path.join(datafiles.dirname,
                             datafiles.basename,
                             'notdict.yaml')

    with pytest.raises(LoadError) as exc:
        context.load(conf_file)

    # XXX Should this be a different LoadErrorReason ?
    assert exc.value.reason == LoadErrorReason.INVALID_YAML