#!/usr/bin/python3
# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:

# Copyright 2014 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser 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.
#
# qutebrowser 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 qutebrowser.  If not, see <http://www.gnu.org/licenses/>.

# pylint: disable=broad-except

""" Run different codecheckers over a codebase.

Runs flake8, pylint, pep257, a CRLF/whitespace/conflict-checker and
pyroma/check-manifest by default.

Module attributes:
    status: An OrderedDict for return status values.
    option: A dictionary with options.
"""

import sys
import subprocess
import os
import os.path
import unittest
import logging
import tokenize
import configparser
import argparse
from collections import OrderedDict
from functools import partial

import pep257
from pkg_resources import load_entry_point, DistributionNotFound

# We need to do this because pyroma is braindead enough to use logging instead
# of print...
logging.basicConfig(level=logging.INFO, format='%(msg)s')

status = OrderedDict()


config = configparser.ConfigParser()
config.read('.run_checks')


def run(name, target=None):
    """Run a checker via distutils with optional args.

    Arguments:
        name: Name of the checker/binary
        target: The package to check
    """
    # pylint: disable=too-many-branches
    args = _get_args(name)
    if name == 'pylint':
        scriptdir = os.path.abspath(os.path.dirname(__file__))
        if 'PYTHONPATH' in os.environ:
            old_pythonpath = os.environ['PYTHONPATH']
            os.environ['PYTHONPATH'] += os.pathsep + scriptdir
        else:
            old_pythonpath = None
            os.environ['PYTHONPATH'] = scriptdir
    sys.argv = [name]
    if target is None:
        status_key = name
    else:
        status_key = '{}_{}'.format(name, target)
        args.append(target)
    if args is not None:
        sys.argv += args
    try:
        ep = load_entry_point(name, 'console_scripts', name)
        ep()
    except SystemExit as e:
        import pdb; pdb.set_trace()  # XXX BREAKPOINT
        status[status_key] = e
    except DistributionNotFound:
        if args is None:
            args = []
        try:
            status[status_key] = subprocess.call([name] + args)
        except FileNotFoundError as e:
            print('{}: {}'.format(e.__class__.__name__, e))
            status[status_key] = None
    except Exception as e:
        print('{}: {}'.format(e.__class__.__name__, e))
        status[status_key] = None
    if name == 'pylint':
        if old_pythonpath is not None:
            os.environ['PYTHONPATH'] = old_pythonpath
        else:
            del os.environ['PYTHONPATH']
    print()


def check_pep257(target):
    """Run pep257 checker with args passed."""
    args = _get_args('pep257')
    sys.argv = ['pep257', target]
    if args is not None:
        sys.argv += args
    try:
        status['pep257_' + target] = pep257.main(*pep257.parse_options())
    except Exception as e:
        print('{}: {}'.format(e.__class__.__name__, e))
        status['pep257_' + target] = None
    print()


def check_unittest():
    """Run the unittest checker."""
    suite = unittest.TestLoader().discover('.')
    result = unittest.TextTestRunner().run(suite)
    print()
    status['unittest'] = result.wasSuccessful()


def check_git():
    """Check for uncommited git files.."""
    if not os.path.isdir(".git"):
        print("No .git dir, ignoring")
        status['git'] = False
        print()
        return
    untracked = []
    gitst = subprocess.check_output(['git', 'status', '--porcelain'])
    gitst = gitst.decode('UTF-8').strip()
    for line in gitst.splitlines():
        s, name = line.split(maxsplit=1)
        if s == '??':
            untracked.append(name)
    if untracked:
        status['git'] = False
        print("Untracked files:")
        print('\n'.join(untracked))
    else:
        status['git'] = True
    print()


def check_vcs_conflict(target):
    """Check VCS conflict markers."""
    try:
        ok = True
        for (dirpath, _dirnames, filenames) in os.walk(target):
            for name in (e for e in filenames if e.endswith('.py')):
                fn = os.path.join(dirpath, name)
                with tokenize.open(fn) as f:
                    for line in f:
                        if any(line.startswith(c * 7) for c in '<>=|'):
                            print("Found conflict marker in {}".format(fn))
                            ok = False
        status['vcs_' + target] = ok
    except Exception as e:
        print('{}: {}'.format(e.__class__.__name__, e))
        status['vcs_' + target] = None
    print()


def _get_args(checker):
    """Construct the arguments for a given checker.

    Return:
        A list of commandline arguments.
    """

    def _get_optional_args(checker):
        """Get a list of arguments based on a comma-separated args config."""
        try:
            return config.get(checker, 'args').split(',')
        except configparser.NoOptionError:
            return []

    def _get_flag(arg, checker, option):
        """Get a list of arguments based on a config option."""
        try:
            return ['--{}={}'.format(arg, config.get(checker, option))]
        except configparser.NoOptionError:
            return []

    args = []
    if checker == 'pylint':
        args += _get_flag('disable', 'pylint', 'disable')
        args += _get_flag('ignore', 'pylint', 'exclude')
        args += _get_optional_args('pylint')
        plugins = []
        for plugin in config.get('pylint', 'plugins').split(','):
            plugins.append('pylint_checkers.{}'.format(plugin))
        args.append('--load-plugins={}'.format(','.join(plugins)))
    elif checker == 'flake8':
        args += _get_flag('ignore', 'flake8', 'disable')
        args += _get_flag('exclude', 'flake8', 'exclude')
        args += _get_optional_args('flake8')
    elif checker == 'pep257':
        args += _get_flag('ignore', 'pep257', 'disable')
        try:
            excluded = config.get('pep257', 'exclude').split(',')
        except configparser.NoOptionError:
            excluded = []
        if os.name == 'nt':
            # FIXME find a better solution
            # pep257 uses cp1252 by default on Windows, which can't handle the
            # unicode chars in some files.
            excluded += ['configdata', 'misc']
        args.append(r'--match=(?!{})\.py'.format('|'.join(excluded)))
        args += _get_optional_args('pep257')
    elif checker == 'pyroma':
        args = ['.']
    elif checker == 'check-manifest':
        args = []
    return args


def _get_checkers(args):
    """Get a dict of checkers we need to execute."""
    checkers = OrderedDict([
        ('global', OrderedDict([
            ('unittest', check_unittest),
            ('git', check_git),
        ])),
        ('setup', OrderedDict([
            ('pyroma', partial(run, 'pyroma')),
            ('check-manifest', partial(run, 'check-manifest')),
        ])),
    ])
    for target in config.get('DEFAULT', 'targets').split(','):
        checkers[target] = OrderedDict([
            ('pep257', partial(check_pep257, target)),
            ('flake8', partial(run, 'flake8', target)),
            ('vcs', partial(check_vcs_conflict, target)),
            ('pylint', partial(run, 'pylint', target)),
        ])
    return checkers


def main():
    """Main entry point."""
    parser = argparse.ArgumentParser(description='Run various checkers.')
    parser.add_argument('-s', '--setup', help="Run additional setup checks",
                        action='store_true')
    parser.add_argument('checkers', help="Checkers to run (or 'all')",
                        default='all', nargs='?')
    args = parser.parse_args()

    checkers = _get_checkers(args)

    groups = ['global']
    groups += config.get('DEFAULT', 'targets').split(',')
    if args.setup:
        groups.append('setup')

    for group in groups:
        print()
        print("==================== {} ====================".format(group))
        if args.checkers == 'all':
            configured_checkers = None
        else:
            configured_checkers = args.checkers.split(',')
        for name, func in checkers[group].items():
            if configured_checkers is None or name in configured_checkers:
                print("------ {} ------".format(name))
                func()

    print("Exit status values:")
    for (k, v) in status.items():
        print('  {} - {}'.format(k, v))

    if all(val in (True, 0) for val in status):
        return 0
    else:
        return 1


if __name__ == '__main__':
    sys.exit(main())