#!/usr/bin/env python
import os
import six
import click
from click.formatting import join_options

from sentry.runner import cli as root_command


def get_opts(param):
    any_prefix_is_slash = []
    def _write(opts):
        rv, any_slashes = join_options(opts)
        if any_slashes:
            any_prefix_is_slash[:] = [True]
        if not param.is_flag and not param.count:
            rv += ' ' + param.make_metavar()
        return rv
    rv = [_write(param.opts)]
    if param.secondary_opts:
        rv.append(_write(param.secondary_opts))
    return (any_prefix_is_slash and '; ' or ' / ').join(rv)


def write_page(out, data):
    path = data['path']
    filename = os.path.join(out, *path[1:]) + '/index.rst'
    if len(path) == 1:
        filename += '.inc'

    dirname = os.path.dirname(filename)
    try:
        os.makedirs(dirname)
    except OSError:
        pass

    args = [x['metavar'] for x in data['arguments']]
    title = '`%s`' % ' '.join(data['path'] + args)
    body = [
        title,
        '-' * len(title),
        '',
        data['help'] or '',
    ]

    body.append('')
    body.append('Options')
    body.append('```````')
    body.append('')
    for opt in data['options']:
        prefix = '- ``%s``: ' % opt['opt_string']
        for line in click.wrap_text(
                opt['help'], 74, prefix, '  ').splitlines() or ['']:
            body.append(line)
    body.append('- ``--help``: print this help page.')

    if data['subcommands']:
        body.append('')
        body.append('Subcommands')
        body.append('```````````')
        body.append('')
        body.append('.. toctree::')
        body.append(' :maxdepth: 1')
        body.append('')
        for subcmd in data['subcommands']:
            body.append(' %s <%s/index>' % (subcmd, subcmd))
        body.append('')

    with open(filename, 'w') as f:
        for line in body:
            f.write('%s\n' % line.encode('utf-8'))


class NoHelp(Exception):
    pass


def dump_command(out, cmd, path):
    if cmd.help is None:
        raise NoHelp
    data = {
        'path': path,
        'help': cmd.help.replace('\b', ''),
        'options': [],
        'arguments': [],
        'subcommands': [],
    }

    for param in cmd.params:
        if isinstance(param, click.Option):
            help_text = param.help or ''
            if param.show_default:
                help_text += '  [default: %s]' % (
                         ', '.join('%s' % d for d in param.default)
                         if isinstance(param.default, (list, tuple))
                         else (param.default,))
            data['options'].append({
                'opt_string': get_opts(param),
                'help': help_text,
            })
        else:
            data['arguments'].append({
                'metavar': param.make_metavar(),
            })

    if isinstance(cmd, click.Group):
        for child_name, child_cmd in six.iteritems(cmd.commands):
            try:
                dump_command(out, child_cmd, path + [child_name])
            except NoHelp:
                pass
            else:
                data['subcommands'].append(child_name)

    write_page(out, data)


@click.command()
@click.option('--output-path', 'out', type=click.Path(),
              default='build/cli-help')
def cli(out):
    dump_command(out, root_command, ['sentry'])


if __name__ == '__main__':
    cli()