# Copyright 2016-2021 The Meson development team

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from pathlib import PurePath
from unittest import mock, TestCase, SkipTest
import json
import os
import re
import subprocess
import sys
import tempfile
import typing as T

import mesonbuild.mlog
import mesonbuild.depfile
import mesonbuild.dependencies.base
import mesonbuild.dependencies.factory
import mesonbuild.compilers
import mesonbuild.envconfig
import mesonbuild.environment
import mesonbuild.coredata
import mesonbuild.modules.gnome
from mesonbuild.mesonlib import (
    is_cygwin, windows_proof_rmtree, python_command
)
import mesonbuild.modules.pkgconfig


from run_tests import (
    Backend, ensure_backend_detects_changes, get_backend_commands,
    get_builddir_target_args, get_meson_script, run_configure_inprocess,
    run_mtest_inprocess
)


class BasePlatformTests(TestCase):
    prefix = '/usr'
    libdir = 'lib'

    def setUp(self):
        super().setUp()
        self.maxDiff = None
        src_root = str(PurePath(__file__).parents[1])
        self.src_root = src_root
        # Get the backend
        self.backend = getattr(Backend, os.environ['MESON_UNIT_TEST_BACKEND'])
        self.meson_args = ['--backend=' + self.backend.name]
        self.meson_native_files = []
        self.meson_cross_files = []
        self.meson_command = python_command + [get_meson_script()]
        self.setup_command = self.meson_command + self.meson_args
        self.mconf_command = self.meson_command + ['configure']
        self.mintro_command = self.meson_command + ['introspect']
        self.wrap_command = self.meson_command + ['wrap']
        self.rewrite_command = self.meson_command + ['rewrite']
        # Backend-specific build commands
        self.build_command, self.clean_command, self.test_command, self.install_command, \
            self.uninstall_command = get_backend_commands(self.backend)
        # Test directories
        self.common_test_dir = os.path.join(src_root, 'test cases/common')
        self.rust_test_dir = os.path.join(src_root, 'test cases/rust')
        self.vala_test_dir = os.path.join(src_root, 'test cases/vala')
        self.framework_test_dir = os.path.join(src_root, 'test cases/frameworks')
        self.unit_test_dir = os.path.join(src_root, 'test cases/unit')
        self.rewrite_test_dir = os.path.join(src_root, 'test cases/rewrite')
        self.linuxlike_test_dir = os.path.join(src_root, 'test cases/linuxlike')
        self.objc_test_dir = os.path.join(src_root, 'test cases/objc')
        self.objcpp_test_dir = os.path.join(src_root, 'test cases/objcpp')

        # Misc stuff
        self.orig_env = os.environ.copy()
        if self.backend is Backend.ninja:
            self.no_rebuild_stdout = ['ninja: no work to do.', 'samu: nothing to do']
        else:
            # VS doesn't have a stable output when no changes are done
            # XCode backend is untested with unit tests, help welcome!
            self.no_rebuild_stdout = [f'UNKNOWN BACKEND {self.backend.name!r}']

        self.builddirs = []
        self.new_builddir()

    def change_builddir(self, newdir):
        self.builddir = newdir
        self.privatedir = os.path.join(self.builddir, 'meson-private')
        self.logdir = os.path.join(self.builddir, 'meson-logs')
        self.installdir = os.path.join(self.builddir, 'install')
        self.distdir = os.path.join(self.builddir, 'meson-dist')
        self.mtest_command = self.meson_command + ['test', '-C', self.builddir]
        self.builddirs.append(self.builddir)

    def new_builddir(self):
        # Keep builddirs inside the source tree so that virus scanners
        # don't complain
        newdir = tempfile.mkdtemp(dir=os.getcwd())
        # In case the directory is inside a symlinked directory, find the real
        # path otherwise we might not find the srcdir from inside the builddir.
        newdir = os.path.realpath(newdir)
        self.change_builddir(newdir)

    def new_builddir_in_tempdir(self):
        # Can't keep the builddir inside the source tree for the umask tests:
        # https://github.com/mesonbuild/meson/pull/5546#issuecomment-509666523
        # And we can't do this for all tests because it causes the path to be
        # a short-path which breaks other tests:
        # https://github.com/mesonbuild/meson/pull/9497
        newdir = tempfile.mkdtemp()
        # In case the directory is inside a symlinked directory, find the real
        # path otherwise we might not find the srcdir from inside the builddir.
        newdir = os.path.realpath(newdir)
        self.change_builddir(newdir)

    def _get_meson_log(self) -> T.Optional[str]:
        log = os.path.join(self.logdir, 'meson-log.txt')
        if not os.path.isfile(log):
            print(f"{log!r} doesn't exist", file=sys.stderr)
            return None
        with open(log, encoding='utf-8') as f:
            return f.read()

    def _print_meson_log(self) -> None:
        log = self._get_meson_log()
        if log:
            print(log)

    def tearDown(self):
        for path in self.builddirs:
            try:
                windows_proof_rmtree(path)
            except FileNotFoundError:
                pass
        os.environ.clear()
        os.environ.update(self.orig_env)
        super().tearDown()

    def _run(self, command, *, workdir=None, override_envvars: T.Optional[T.Mapping[str, str]] = None):
        '''
        Run a command while printing the stdout and stderr to stdout,
        and also return a copy of it
        '''
        # If this call hangs CI will just abort. It is very hard to distinguish
        # between CI issue and test bug in that case. Set timeout and fail loud
        # instead.
        if override_envvars is None:
            env = None
        else:
            env = os.environ.copy()
            env.update(override_envvars)

        p = subprocess.run(command, stdout=subprocess.PIPE,
                           stderr=subprocess.STDOUT, env=env,
                           encoding='utf-8',
                           universal_newlines=True, cwd=workdir, timeout=60 * 5)
        print(p.stdout)
        if p.returncode != 0:
            if 'MESON_SKIP_TEST' in p.stdout:
                raise SkipTest('Project requested skipping.')
            raise subprocess.CalledProcessError(p.returncode, command, output=p.stdout)
        return p.stdout

    def init(self, srcdir, *,
             extra_args=None,
             default_args=True,
             inprocess=False,
             override_envvars: T.Optional[T.Mapping[str, str]] = None,
             workdir=None,
             allow_fail: bool = False) -> str:
        """Call `meson setup`

        :param allow_fail: If set to true initialization is allowed to fail.
            When it does the log will be returned instead of stdout.
        :return: the value of stdout on success, or the meson log on failure
            when :param allow_fail: is true
        """
        self.assertPathExists(srcdir)
        if extra_args is None:
            extra_args = []
        if not isinstance(extra_args, list):
            extra_args = [extra_args]
        args = [srcdir, self.builddir]
        if default_args:
            args += ['--prefix', self.prefix]
            if self.libdir:
                args += ['--libdir', self.libdir]
            for f in self.meson_native_files:
                args += ['--native-file', f]
            for f in self.meson_cross_files:
                args += ['--cross-file', f]
        self.privatedir = os.path.join(self.builddir, 'meson-private')
        if inprocess:
            try:
                returncode, out, err = run_configure_inprocess(self.meson_args + args + extra_args, override_envvars)
            except Exception as e:
                if not allow_fail:
                    self._print_meson_log()
                    raise
                out = self._get_meson_log()  # Best we can do here
                err = ''  # type checkers can't figure out that on this path returncode will always be 0
                returncode = 0
            finally:
                # Close log file to satisfy Windows file locking
                mesonbuild.mlog.shutdown()
                mesonbuild.mlog.log_dir = None
                mesonbuild.mlog.log_file = None

            if 'MESON_SKIP_TEST' in out:
                raise SkipTest('Project requested skipping.')
            if returncode != 0:
                self._print_meson_log()
                print('Stdout:\n')
                print(out)
                print('Stderr:\n')
                print(err)
                if not allow_fail:
                    raise RuntimeError('Configure failed')
        else:
            try:
                out = self._run(self.setup_command + args + extra_args, override_envvars=override_envvars, workdir=workdir)
            except SkipTest:
                raise SkipTest('Project requested skipping: ' + srcdir)
            except Exception:
                if not allow_fail:
                    self._print_meson_log()
                    raise
                out = self._get_meson_log()  # best we can do here
        return out

    def build(self, target=None, *, extra_args=None, override_envvars=None):
        if extra_args is None:
            extra_args = []
        # Add arguments for building the target (if specified),
        # and using the build dir (if required, with VS)
        args = get_builddir_target_args(self.backend, self.builddir, target)
        return self._run(self.build_command + args + extra_args, workdir=self.builddir, override_envvars=override_envvars)

    def clean(self, *, override_envvars=None):
        dir_args = get_builddir_target_args(self.backend, self.builddir, None)
        self._run(self.clean_command + dir_args, workdir=self.builddir, override_envvars=override_envvars)

    def run_tests(self, *, inprocess=False, override_envvars=None):
        if not inprocess:
            return self._run(self.test_command, workdir=self.builddir, override_envvars=override_envvars)
        else:
            with mock.patch.dict(os.environ, override_envvars):
                return run_mtest_inprocess(['-C', self.builddir])[1]

    def install(self, *, use_destdir=True, override_envvars=None):
        if self.backend is not Backend.ninja:
            raise SkipTest(f'{self.backend.name!r} backend can\'t install files')
        if use_destdir:
            destdir = {'DESTDIR': self.installdir}
            if override_envvars is None:
                override_envvars = destdir
            else:
                override_envvars.update(destdir)
        return self._run(self.install_command, workdir=self.builddir, override_envvars=override_envvars)

    def uninstall(self, *, override_envvars=None):
        self._run(self.uninstall_command, workdir=self.builddir, override_envvars=override_envvars)

    def run_target(self, target, *, override_envvars=None):
        '''
        Run a Ninja target while printing the stdout and stderr to stdout,
        and also return a copy of it
        '''
        return self.build(target=target, override_envvars=override_envvars)

    def setconf(self, arg, will_build=True):
        if not isinstance(arg, list):
            arg = [arg]
        if will_build:
            ensure_backend_detects_changes(self.backend)
        self._run(self.mconf_command + arg + [self.builddir])

    def wipe(self):
        windows_proof_rmtree(self.builddir)

    def utime(self, f):
        ensure_backend_detects_changes(self.backend)
        os.utime(f)

    def get_compdb(self):
        if self.backend is not Backend.ninja:
            raise SkipTest(f'Compiler db not available with {self.backend.name} backend')
        try:
            with open(os.path.join(self.builddir, 'compile_commands.json'), encoding='utf-8') as ifile:
                contents = json.load(ifile)
        except FileNotFoundError:
            raise SkipTest('Compiler db not found')
        # If Ninja is using .rsp files, generate them, read their contents, and
        # replace it as the command for all compile commands in the parsed json.
        if len(contents) > 0 and contents[0]['command'].endswith('.rsp'):
            # Pretend to build so that the rsp files are generated
            self.build(extra_args=['-d', 'keeprsp', '-n'])
            for each in contents:
                # Extract the actual command from the rsp file
                compiler, rsp = each['command'].split(' @')
                rsp = os.path.join(self.builddir, rsp)
                # Replace the command with its contents
                with open(rsp, encoding='utf-8') as f:
                    each['command'] = compiler + ' ' + f.read()
        return contents

    def get_meson_log(self):
        with open(os.path.join(self.builddir, 'meson-logs', 'meson-log.txt'), encoding='utf-8') as f:
            return f.readlines()

    def get_meson_log_compiler_checks(self):
        '''
        Fetch a list command-lines run by meson for compiler checks.
        Each command-line is returned as a list of arguments.
        '''
        log = self.get_meson_log()
        prefix = 'Command line:'
        cmds = [l[len(prefix):].split() for l in log if l.startswith(prefix)]
        return cmds

    def get_meson_log_sanitychecks(self):
        '''
        Same as above, but for the sanity checks that were run
        '''
        log = self.get_meson_log()
        prefix = 'Sanity check compiler command line:'
        cmds = [l[len(prefix):].split() for l in log if l.startswith(prefix)]
        return cmds

    def introspect(self, args):
        if isinstance(args, str):
            args = [args]
        out = subprocess.check_output(self.mintro_command + args + [self.builddir],
                                      universal_newlines=True)
        return json.loads(out)

    def introspect_directory(self, directory, args):
        if isinstance(args, str):
            args = [args]
        out = subprocess.check_output(self.mintro_command + args + [directory],
                                      universal_newlines=True)
        try:
            obj = json.loads(out)
        except Exception as e:
            print(out)
            raise e
        return obj

    def assertPathEqual(self, path1, path2):
        '''
        Handles a lot of platform-specific quirks related to paths such as
        separator, case-sensitivity, etc.
        '''
        self.assertEqual(PurePath(path1), PurePath(path2))

    def assertPathListEqual(self, pathlist1, pathlist2):
        self.assertEqual(len(pathlist1), len(pathlist2))
        worklist = list(zip(pathlist1, pathlist2))
        for i in worklist:
            if i[0] is None:
                self.assertEqual(i[0], i[1])
            else:
                self.assertPathEqual(i[0], i[1])

    def assertPathBasenameEqual(self, path, basename):
        msg = f'{path!r} does not end with {basename!r}'
        # We cannot use os.path.basename because it returns '' when the path
        # ends with '/' for some silly reason. This is not how the UNIX utility
        # `basename` works.
        path_basename = PurePath(path).parts[-1]
        self.assertEqual(PurePath(path_basename), PurePath(basename), msg)

    def assertReconfiguredBuildIsNoop(self):
        'Assert that we reconfigured and then there was nothing to do'
        ret = self.build()
        self.assertIn('The Meson build system', ret)
        if self.backend is Backend.ninja:
            for line in ret.split('\n'):
                if line in self.no_rebuild_stdout:
                    break
            else:
                raise AssertionError('build was reconfigured, but was not no-op')
        elif self.backend is Backend.vs:
            # Ensure that some target said that no rebuild was done
            # XXX: Note CustomBuild did indeed rebuild, because of the regen checker!
            self.assertIn('ClCompile:\n  All outputs are up-to-date.', ret)
            self.assertIn('Link:\n  All outputs are up-to-date.', ret)
            # Ensure that no targets were built
            self.assertNotRegex(ret, re.compile('ClCompile:\n [^\n]*cl', flags=re.IGNORECASE))
            self.assertNotRegex(ret, re.compile('Link:\n [^\n]*link', flags=re.IGNORECASE))
        elif self.backend is Backend.xcode:
            raise SkipTest('Please help us fix this test on the xcode backend')
        else:
            raise RuntimeError(f'Invalid backend: {self.backend.name!r}')

    def assertBuildIsNoop(self):
        ret = self.build()
        if self.backend is Backend.ninja:
            self.assertIn(ret.split('\n')[-2], self.no_rebuild_stdout)
        elif self.backend is Backend.vs:
            # Ensure that some target of each type said that no rebuild was done
            # We always have at least one CustomBuild target for the regen checker
            self.assertIn('CustomBuild:\n  All outputs are up-to-date.', ret)
            self.assertIn('ClCompile:\n  All outputs are up-to-date.', ret)
            self.assertIn('Link:\n  All outputs are up-to-date.', ret)
            # Ensure that no targets were built
            self.assertNotRegex(ret, re.compile('CustomBuild:\n [^\n]*cl', flags=re.IGNORECASE))
            self.assertNotRegex(ret, re.compile('ClCompile:\n [^\n]*cl', flags=re.IGNORECASE))
            self.assertNotRegex(ret, re.compile('Link:\n [^\n]*link', flags=re.IGNORECASE))
        elif self.backend is Backend.xcode:
            raise SkipTest('Please help us fix this test on the xcode backend')
        else:
            raise RuntimeError(f'Invalid backend: {self.backend.name!r}')

    def assertRebuiltTarget(self, target):
        ret = self.build()
        if self.backend is Backend.ninja:
            self.assertIn(f'Linking target {target}', ret)
        elif self.backend is Backend.vs:
            # Ensure that this target was rebuilt
            linkre = re.compile('Link:\n [^\n]*link[^\n]*' + target, flags=re.IGNORECASE)
            self.assertRegex(ret, linkre)
        elif self.backend is Backend.xcode:
            raise SkipTest('Please help us fix this test on the xcode backend')
        else:
            raise RuntimeError(f'Invalid backend: {self.backend.name!r}')

    @staticmethod
    def get_target_from_filename(filename):
        base = os.path.splitext(filename)[0]
        if base.startswith(('lib', 'cyg')):
            return base[3:]
        return base

    def assertBuildRelinkedOnlyTarget(self, target):
        ret = self.build()
        if self.backend is Backend.ninja:
            linked_targets = []
            for line in ret.split('\n'):
                if 'Linking target' in line:
                    fname = line.rsplit('target ')[-1]
                    linked_targets.append(self.get_target_from_filename(fname))
            self.assertEqual(linked_targets, [target])
        elif self.backend is Backend.vs:
            # Ensure that this target was rebuilt
            linkre = re.compile(r'Link:\n  [^\n]*link.exe[^\n]*/OUT:".\\([^"]*)"', flags=re.IGNORECASE)
            matches = linkre.findall(ret)
            self.assertEqual(len(matches), 1, msg=matches)
            self.assertEqual(self.get_target_from_filename(matches[0]), target)
        elif self.backend is Backend.xcode:
            raise SkipTest('Please help us fix this test on the xcode backend')
        else:
            raise RuntimeError(f'Invalid backend: {self.backend.name!r}')

    def assertPathExists(self, path):
        m = f'Path {path!r} should exist'
        self.assertTrue(os.path.exists(path), msg=m)

    def assertPathDoesNotExist(self, path):
        m = f'Path {path!r} should not exist'
        self.assertFalse(os.path.exists(path), msg=m)
