#!/usr/bin/env python3
import difflib
import functools
from typing import Callable

import click
from clintermission import cli_select_item  # type: ignore
import editor  # type: ignore
from sievelib.managesieve import Client  # type: ignore


def default_options(f: Callable) -> Callable:
    @click.option('--server', prompt=True, help='sieve server to connect to')
    @click.option('-u', '--user', prompt=True, help='user to connect as')
    @click.option('--password', prompt=True, hide_input=True,
                  help='Passwort to connect with. It\'s discouraged to pass passwords.'
                       'Use the automatic prompt instead.')
    @click.option('--starttls/--no-starttls', default=True, help='Connect with starttls')
    @functools.wraps(f)
    def wrapper(*args, **kwargs):
        f(*args, **kwargs)

    return wrapper


@click.group()
def main():
    pass


@main.command()
@default_options
@click.option('--script-name',
              help='script name to set as active. If not provided, choices will be presented.')
def active(server: str, user: str, password: str, starttls: bool, script_name: str) -> int:
    """Connect to a SIEVE server and set a script as active"""
    c = Client(server)
    c.connect(user, password, starttls=starttls)
    active, scripts = c.listscripts()

    if not script_name:
        if len(scripts + [active]) == 1:
            click.echo('Only a single script available: {}'.format((scripts + [active])[0]))
        _, script_name = cli_select_item(zip(sorted(['{} (active)'.format(active)] + scripts),
                                             sorted([active] + scripts)))

    if active == script_name:
        click.echo('Script {} is already active.'.format(script_name))
        return 0

    if script_name not in scripts:
        click.echo('Error: script {} cannot be found. Valid choices are: {}'
                   .format(script_name, ', '.join(scripts)))
        return 1

    c.setactive(script_name)
    return 0


DEFAULT_TEMPLATE = """\
# Example script. Edit as you like
require ["fileinto"];
# rule:[amazon]
if header :contains "To" "amazon@" {
  fileinto "INBOX.amazon";
  stop;
}
# rule:[games]
if anyof (header :contains "To" "gw2@",
    header :contains "To" "humblebundle@",
    header :contains "To" "steam@",
    header :contains "To" "socialclub@",
    header :contains "To" "uplay@" ) {
  fileinto "INBOX.games";
  stop;
}
# rule:[paypal]
if header :contains "To" "paypal@" {
  fileinto "INBOX.paypal";
  stop;
}
"""


@main.command()
@default_options
@click.option('--script-name', help='Edit this script or create it')
def edit(server: str, user: str, password: str, starttls: bool, script_name: str) -> None:
    """Connect to a SIEVE server, download, edit and upload a script"""
    c = Client(server)
    c.connect(user, password, starttls=starttls)
    active, scripts = c.listscripts()

    if not script_name:
        _, script_name = cli_select_item(zip(sorted(['{} (active)'.format(active)] + scripts),
                                             sorted([active] + scripts)))
    if script_name not in (scripts + [active]):
        msg = 'Script {} does not exist. Create new script?'
        click.confirm(msg.format(script_name), abort=True)
        original_content = DEFAULT_TEMPLATE
        newly_created = True
    else:
        original_content = c.getscript(script_name)
        newly_created = False

    new_content = editor.edit(contents=original_content).decode('utf-8')
    if new_content.strip() == original_content and not newly_created:
        click.echo('No changes. Aborting.')
        return

    while not c.checkscript(new_content):
        click.confirm('Script is invalid. Try again?', abort=True)
        new_content = editor.edit(contents=new_content).decode('utf-8')
        if new_content == original_content and not newly_created:
            click.echo('No changes. Aborting.')
            return

    diff = difflib.unified_diff(original_content.splitlines(), new_content.splitlines(),
                                fromfile='before', tofile='after')
    if not newly_created:
        click.echo('Following changes were made:\n{}'.format('\n'.join(diff)))
    click.confirm('Upload new version?', abort=True)

    c.putscript(script_name, new_content)


if __name__ == '__main__':
    main()