#  yaclog: yet another changelog tool
#  Copyright (c) 2021. Andrew Cassidy
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU Affero General Public License as
#  published by the Free Software Foundation, either version 3 of the
#  License, or (at your option) any later version.
#
#  This program 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 Affero General Public License for more details.
#
#  You should have received a copy of the GNU Affero General Public License
#  along with this program.  If not, see <https://www.gnu.org/licenses/>.

import click
import yaclog
import os.path
from yaclog import Changelog


@click.group()
@click.option('--path', envvar='YACLOG_PATH', default='CHANGELOG.md', show_default=True,
              type=click.Path(dir_okay=False, writable=True, readable=True),
              help='Location of the changelog file.')
@click.version_option()
@click.pass_context
def cli(ctx, path):
    """Manipulate markdown changelog files."""
    if not (ctx.invoked_subcommand == 'init') and not os.path.exists(path):
        # file does not exist and this isn't the init command
        raise click.FileError(f'Changelog file {path} does not exist. Create it by running `yaclog init`.')

    ctx.obj = yaclog.read(path)


@cli.command()
@click.pass_obj
def init(obj: Changelog):
    """Create a new changelog file."""
    if os.path.exists(obj.path):
        click.confirm(f'Changelog file {obj.path} already exists. Would you like to overwrite it?', abort=True)
        os.remove(obj.path)

    yaclog.Changelog(obj.path).write()
    print(f'Created new changelog file at {obj.path}')


@cli.command('format')  # dont accidentally hide the `format` python builtin
@click.pass_obj
def reformat(obj: Changelog):
    """Reformat the changelog file."""
    obj.write()
    print(f'Reformatted changelog file at {obj.path}')


@cli.command(short_help='Show changes from the changelog file')
@click.option('--all', '-a', 'all_versions', is_flag=True, help='Show the entire changelog.')
@click.argument('versions', type=str, nargs=-1)
@click.pass_obj
def show(obj: Changelog, all_versions, versions):
    """Show the changes for VERSIONS.

    VERSIONS is a list of versions to print. If not given, the most recent version is used.
    """
    if all_versions:
        with open(obj.path, 'r') as fp:
            click.echo_via_pager(fp.read())
    else:
        if len(versions):
            v_list = []
            for v_name in versions:
                matches = [v for v in obj.versions if v.name == v_name]
                if len(matches) == 0:
                    raise click.BadArgumentUsage(f'Version "{v_name}" not found in changelog.')
                v_list += matches
        else:
            v_list = [obj.versions[0]]

        for v in v_list:
            click.echo(v.text(False))


@cli.command(short_help='Modify version tags')
@click.option('--add/--delete', '-a/-d', default=True, is_flag=True, help='Add or delete tags')
@click.argument('tag_name', metavar='tag', type=str)
@click.argument('version_name', metavar='version', type=str, required=False)
@click.pass_obj
def tag(obj: Changelog, add, tag_name: str, version_name: str):
    """Modify TAG on VERSION.

    VERSION is the name of a version to add tags to. If not given, the most recent version is used.
    """
    tag_name = tag_name.upper()
    if version_name:
        matches = [v for v in obj.versions if v.name == version_name]
        if len(matches) == 0:
            raise click.BadArgumentUsage(f'Version "{version_name}" not found in changelog.')
        version = matches[0]
    else:
        version = obj.versions[0]

    if add:
        version.tags.append(tag_name)
    else:
        try:
            version.tags.remove(tag_name)
        except ValueError:
            raise click.BadArgumentUsage(f'Tag "{tag_name}" not found in version "{version.name}".')

    obj.write()


@cli.command()
@click.option('--bullet', '-b', 'bullets', multiple=True, type=str,
              help='Bullet points to add. '
                   'When multiple bullet points are provided, additional points are added as sub-points.')
@click.option('--paragraph', '-p', 'paragraphs', multiple=True, type=str,
              help='Paragraphs to add')
@click.argument('section_name', metavar='section', type=str)
@click.argument('version_name', metavar='version', type=str, required=False)
@click.pass_obj
def entry(obj: Changelog, bullets, paragraphs, section_name, version_name):
    """Add entries to the changelog"""

    section_name = section_name.title()
    if version_name:
        matches = [v for v in obj.versions if v.name == version_name]
        if len(matches) == 0:
            raise click.BadArgumentUsage(f'Version "{version_name}" not found in changelog.')
        version = matches[0]
    else:
        version = obj.versions[0]

    if section_name not in version.sections.keys():
        version.sections[section_name] = []

    section = version.sections[section_name]
    section += paragraphs

    sub_bullet = False
    for bullet in bullets:
        bullet = bullet.strip()
        if bullet[0] not in ['-+*']:
            bullet = '- ' + bullet

        if sub_bullet:
            bullet = '    ' + bullet

        section.append(bullet)

        sub_bullet = True

    obj.write()


if __name__ == '__main__':
    cli()