#!/usr/bin/python
# -*- coding: utf-8 -*-

# (c) 2013, Daniel Jaouen <dcj24@cornell.edu>
# (c) 2016, Indrajit Raychaudhuri <irc+code@indrajit.com>
#
# Based on homebrew (Andrew Dunham <andrew@du.nham.ca>)
#
# This file is part of Ansible
#
# Ansible 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.
#
# Ansible 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 Ansible.  If not, see <http://www.gnu.org/licenses/>.

import re

ANSIBLE_METADATA = {'status': ['preview'],
                    'supported_by': 'community',
                    'version': '1.0'}

DOCUMENTATION = '''
---
module: homebrew_tap
author:
    - "Indrajit Raychaudhuri (@indrajitr)"
    - "Daniel Jaouen (@danieljaouen)"
short_description: Tap a Homebrew repository.
description:
    - Tap external Homebrew repositories.
version_added: "1.6"
options:
    name:
        description:
            - The GitHub user/organization repository to tap.
        required: true
        aliases: ['tap']
    url:
        description:
            - The optional git URL of the repository to tap. The URL is not
              assumed to be on GitHub, and the protocol doesn't have to be HTTP.
              Any location and protocol that git can handle is fine.
        required: false
        version_added: "2.2"
        note:
            - I(name) option may not be a list of multiple taps (but a single
              tap instead) when this option is provided.
    state:
        description:
            - state of the repository.
        choices: [ 'present', 'absent' ]
        required: false
        default: 'present'
requirements: [ homebrew ]
'''

EXAMPLES = '''
- homebrew_tap:
    name: homebrew/dupes

- homebrew_tap:
    name: homebrew/dupes
    state: absent

- homebrew_tap:
    name: homebrew/dupes,homebrew/science
    state: present

- homebrew_tap:
    name: telemachus/brew
    url: 'https://bitbucket.org/telemachus/brew'
'''


def a_valid_tap(tap):
    '''Returns True if the tap is valid.'''
    regex = re.compile(r'^([\w-]+)/(homebrew-)?([\w-]+)$')
    return regex.match(tap)


def already_tapped(module, brew_path, tap):
    '''Returns True if already tapped.'''

    rc, out, err = module.run_command([
        brew_path,
        'tap',
    ])

    taps = [tap_.strip().lower() for tap_ in out.split('\n') if tap_]
    tap_name = re.sub('homebrew-', '', tap.lower())

    return tap_name in taps


def add_tap(module, brew_path, tap, url=None):
    '''Adds a single tap.'''
    failed, changed, msg = False, False, ''

    if not a_valid_tap(tap):
        failed = True
        msg = 'not a valid tap: %s' % tap

    elif not already_tapped(module, brew_path, tap):
        if module.check_mode:
            module.exit_json(changed=True)

        rc, out, err = module.run_command([
            brew_path,
            'tap',
            tap,
            url,
        ])
        if already_tapped(module, brew_path, tap):
            changed = True
            msg = 'successfully tapped: %s' % tap
        else:
            failed = True
            msg = 'failed to tap: %s' % tap

    else:
        msg = 'already tapped: %s' % tap

    return (failed, changed, msg)


def add_taps(module, brew_path, taps):
    '''Adds one or more taps.'''
    failed, unchanged, added, msg = False, 0, 0, ''

    for tap in taps:
        (failed, changed, msg) = add_tap(module, brew_path, tap)
        if failed:
            break
        if changed:
            added += 1
        else:
            unchanged += 1

    if failed:
        msg = 'added: %d, unchanged: %d, error: ' + msg
        msg = msg % (added, unchanged)
    elif added:
        changed = True
        msg = 'added: %d, unchanged: %d' % (added, unchanged)
    else:
        msg = 'added: %d, unchanged: %d' % (added, unchanged)

    return (failed, changed, msg)


def remove_tap(module, brew_path, tap):
    '''Removes a single tap.'''
    failed, changed, msg = False, False, ''

    if not a_valid_tap(tap):
        failed = True
        msg = 'not a valid tap: %s' % tap

    elif already_tapped(module, brew_path, tap):
        if module.check_mode:
            module.exit_json(changed=True)

        rc, out, err = module.run_command([
            brew_path,
            'untap',
            tap,
        ])
        if not already_tapped(module, brew_path, tap):
            changed = True
            msg = 'successfully untapped: %s' % tap
        else:
            failed = True
            msg = 'failed to untap: %s' % tap

    else:
        msg = 'already untapped: %s' % tap

    return (failed, changed, msg)


def remove_taps(module, brew_path, taps):
    '''Removes one or more taps.'''
    failed, unchanged, removed, msg = False, 0, 0, ''

    for tap in taps:
        (failed, changed, msg) = remove_tap(module, brew_path, tap)
        if failed:
            break
        if changed:
            removed += 1
        else:
            unchanged += 1

    if failed:
        msg = 'removed: %d, unchanged: %d, error: ' + msg
        msg = msg % (removed, unchanged)
    elif removed:
        changed = True
        msg = 'removed: %d, unchanged: %d' % (removed, unchanged)
    else:
        msg = 'removed: %d, unchanged: %d' % (removed, unchanged)

    return (failed, changed, msg)


def main():
    module = AnsibleModule(
        argument_spec=dict(
            name=dict(aliases=['tap'], type='list', required=True),
            url=dict(default=None, required=False),
            state=dict(default='present', choices=['present', 'absent']),
        ),
        supports_check_mode=True,
    )

    brew_path = module.get_bin_path(
        'brew',
        required=True,
        opt_dirs=['/usr/local/bin']
    )

    taps = module.params['name']
    url = module.params['url']

    if module.params['state'] == 'present':
        if url is None:
            # No tap URL provided explicitly, continue with bulk addition
            # of all the taps.
            failed, changed, msg = add_taps(module, brew_path, taps)
        else:
            # When an tap URL is provided explicitly, we allow adding
            # *single* tap only. Validate and proceed to add single tap.
            if len(taps) > 1:
                msg = "List of muliple taps may not be provided with 'url' option."
                module.fail_json(msg=msg)
            else:
                failed, changed, msg = add_tap(module, brew_path, taps[0], url)

        if failed:
            module.fail_json(msg=msg)
        else:
            module.exit_json(changed=changed, msg=msg)

    elif module.params['state'] == 'absent':
        failed, changed, msg = remove_taps(module, brew_path, taps)

        if failed:
            module.fail_json(msg=msg)
        else:
            module.exit_json(changed=changed, msg=msg)

# this is magic, see lib/ansible/module_common.py
from ansible.module_utils.basic import *

if __name__ == '__main__':
    main()
