from __future__ import unicode_literals

import argparse
import os
import sys

import pkg_resources

from pre_commit import color
from pre_commit import five
from pre_commit import git
from pre_commit.commands.autoupdate import autoupdate
from pre_commit.commands.clean import clean
from pre_commit.commands.install_uninstall import install
from pre_commit.commands.install_uninstall import uninstall
from pre_commit.commands.run import run
from pre_commit.error_handler import error_handler
from pre_commit.runner import Runner


# https://github.com/pre-commit/pre-commit/issues/217
# On OSX, making a virtualenv using pyvenv at . causes `virtualenv` and `pip`
# to install packages to the wrong place.  We don't want anything to deal with
# pyvenv
os.environ.pop('__PYVENV_LAUNCHER__', None)


def main(argv=None):
    argv = argv if argv is not None else sys.argv[1:]
    argv = [five.to_text(arg) for arg in argv]
    parser = argparse.ArgumentParser()

    # http://stackoverflow.com/a/8521644/812183
    parser.add_argument(
        '-V', '--version',
        action='version',
        version='%(prog)s {0}'.format(
            pkg_resources.get_distribution('pre-commit').version
        )
    )

    subparsers = parser.add_subparsers(dest='command')

    install_parser = subparsers.add_parser(
        'install', help='Install the pre-commit script.',
    )
    install_parser.add_argument(
        '-f', '--overwrite', action='store_true',
        help='Overwrite existing hooks / remove migration mode.',
    )
    install_parser.add_argument(
        '--install-hooks', action='store_true',
        help=(
            'Whether to install hook environments for all environments '
            'in the config file.'
        ),
    )
    install_parser.add_argument(
        '-t', '--hook-type', choices=('pre-commit', 'pre-push'),
        default='pre-commit',
    )

    uninstall_parser = subparsers.add_parser(
        'uninstall', help='Uninstall the pre-commit script.',
    )
    uninstall_parser.add_argument(
        '-t', '--hook-type', choices=('pre-commit', 'pre-push'),
        default='pre-commit',
    )

    subparsers.add_parser('clean', help='Clean out pre-commit files.')

    subparsers.add_parser(
        'autoupdate',
        help="Auto-update pre-commit config to the latest repos' versions.",
    )

    run_parser = subparsers.add_parser('run', help='Run hooks.')
    run_parser.add_argument('hook', nargs='?', help='A single hook-id to run')
    run_parser.add_argument(
        '--color', default='auto', type=color.use_color,
        help='Whether to use color in output.  Choices are `always`, `never`, or `auto`.  Defaults to `auto`.',
    )
    run_parser.add_argument(
        '--no-stash', default=False, action='store_true',
        help='Use this option to prevent auto stashing of unstaged files.',
    )
    run_parser.add_argument(
        '--verbose', '-v', action='store_true', default=False,
    )
    run_parser.add_argument(
        '--origin', '-o',
        help='The origin branch\'s commit_id when using `git push`',
    )
    run_parser.add_argument(
        '--source', '-s',
        help='The remote branch\'s commit_id when using `git push`',
    )
    run_parser.add_argument(
        '--allow-unstaged-config', default=False, action='store_true',
        help='Allow an unstaged config to be present.  Note that this will '
        'be stashed before parsing unless --no-stash is specified'
    )
    run_parser.add_argument(
        '--hook-stage', choices=('commit', 'push'), default='commit',
        help='The stage during which the hook is fired e.g. commit or push',
    )
    run_mutex_group = run_parser.add_mutually_exclusive_group(required=False)
    run_mutex_group.add_argument(
        '--all-files', '-a', action='store_true', default=False,
        help='Run on all the files in the repo.  Implies --no-stash.',
    )
    run_mutex_group.add_argument(
        '--files', nargs='*', default=[],
        help='Specific filenames to run hooks on.',
    )

    help = subparsers.add_parser(
        'help', help='Show help for a specific command.'
    )
    help.add_argument('help_cmd', nargs='?', help='Command to show help for.')

    # Argparse doesn't really provide a way to use a `default` subparser
    if len(argv) == 0:
        argv = ['run']
    args = parser.parse_args(argv)
    if args.command == 'run':
        args.files = [
            os.path.relpath(os.path.abspath(filename), git.get_root())
            for filename in args.files
        ]

    if args.command == 'help':
        if args.help_cmd:
            parser.parse_args([args.help_cmd, '--help'])
        else:
            parser.parse_args(['--help'])

    with error_handler():
        runner = Runner.create()

        if args.command == 'install':
            return install(
                runner, overwrite=args.overwrite, hooks=args.install_hooks,
                hook_type=args.hook_type,
            )
        elif args.command == 'uninstall':
            return uninstall(runner, hook_type=args.hook_type)
        elif args.command == 'clean':
            return clean(runner)
        elif args.command == 'autoupdate':
            return autoupdate(runner)
        elif args.command == 'run':
            return run(runner, args)
        else:
            raise NotImplementedError(
                'Command {0} not implemented.'.format(args.command)
            )

        raise AssertionError(
            'Command {0} failed to exit with a returncode'.format(args.command)
        )


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