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

# (c) 2013, Andrew Dunham <andrew@du.nham.ca>
# (c) 2013, Daniel Jaouen <dcj24@cornell.edu>
#
# Based on macports (Jimmy Tang <jcftang@gmail.com>)
#
# This module 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.
#
# This software 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 this software.  If not, see <http://www.gnu.org/licenses/>.

DOCUMENTATION = '''
---
module: homebrew
author: Andrew Dunham
short_description: Package manager for Homebrew
description:
    - Manages Homebrew packages
version_added: "1.1"
options:
    name:
        description:
            - name of package to install/remove
        required: true
    state:
        description:
            - state of the package
        choices: [ 'head', 'latest', 'installed', 'linked', 'uninstalled' ]
        required: false
        default: present
    update_homebrew:
        description:
            - update homebrew itself first
        required: false
        default: "no"
        choices: [ "yes", "no" ]
notes:  []
'''
EXAMPLES = '''
- homebrew: name=foo state=present
- homebrew: name=foo state=present update_homebrew=yes
- homebrew: name=foo state=latest update_homebrew=yes
- homebrew: update_homebrew=yes upgrade=yes
- homebrew: name=foo state=head
- homebrew: name=foo state=linked
- homebrew: name=foo state=absent
- homebrew: name=foo,bar state=absent
'''

import os.path
import re


# exceptions -------------------------------------------------------------- {{{
class HomebrewException(Exception):
    pass
# /exceptions ------------------------------------------------------------- }}}


# utils ------------------------------------------------------------------- {{{
def _create_regex_group(s):
    lines = (line.strip() for line in s.split('\n') if line.strip())
    chars = filter(None, (line.split('#')[0].strip() for line in lines))
    group = r'[^' + r''.join(chars) + r']'
    return re.compile(group)
# /utils ------------------------------------------------------------------ }}}


class Homebrew(object):
    '''A class to manage Homebrew packages.'''

    # class regexes ------------------------------------------------ {{{
    VALID_PATH_CHARS = r'''
        \w                  # alphanumeric characters (i.e., [a-zA-Z0-9_])
        \s                  # spaces
        :                   # colons
        {sep}               # the OS-specific path separator
        -                   # dashes
    '''.format(sep=os.path.sep)

    VALID_BREW_PATH_CHARS = r'''
        \w                  # alphanumeric characters (i.e., [a-zA-Z0-9_])
        \s                  # spaces
        {sep}               # the OS-specific path separator
        -                   # dashes
    '''.format(sep=os.path.sep)

    VALID_PACKAGE_CHARS = r'''
        \w                  # alphanumeric characters (i.e., [a-zA-Z0-9_])
        -                   # dashes
    '''

    INVALID_PATH_REGEX        = _create_regex_group(VALID_PATH_CHARS)
    INVALID_BREW_PATH_REGEX   = _create_regex_group(VALID_BREW_PATH_CHARS)
    INVALID_PACKAGE_REGEX     = _create_regex_group(VALID_PACKAGE_CHARS)
    # /class regexes ----------------------------------------------- }}}

    # class validations -------------------------------------------- {{{
    @classmethod
    def valid_path(cls, path):
        '''
        `path` must be one of:
         - list of paths
         - a string containing only:
             - alphanumeric characters
             - dashes
             - spaces
             - colons
             - os.path.sep
        '''

        if isinstance(path, basestring):
            return not cls.INVALID_PATH_REGEX.search(path)

        try:
            iter(path)
        except TypeError:
            return False
        else:
            paths = path
            return all(cls.valid_brew_path(path_) for path_ in paths)

    @classmethod
    def valid_brew_path(cls, brew_path):
        '''
        `brew_path` must be one of:
         - None
         - a string containing only:
             - alphanumeric characters
             - dashes
             - spaces
             - os.path.sep
        '''

        if brew_path is None:
            return True

        return (
            isinstance(brew_path, basestring)
            and not cls.INVALID_BREW_PATH_REGEX.search(brew_path)
        )

    @classmethod
    def valid_package(cls, package):
        '''A valid package is either None or alphanumeric.'''

        if package is None:
            return True

        return (
            isinstance(package, basestring)
            and not cls.INVALID_PACKAGE_REGEX.search(package)
        )

    @classmethod
    def valid_state(cls, state):
        '''
        A valid state is one of:
            - None
            - installed
            - upgraded
            - head
            - linked
            - unlinked
            - absent
        '''

        if state is None:
            return True
        else:
            return (
                isinstance(state, basestring)
                and state.lower() in (
                    'installed',
                    'upgraded',
                    'head',
                    'linked',
                    'unlinked',
                    'absent',
                )
            )

    @classmethod
    def valid_module(cls, module):
        '''A valid module is an instance of AnsibleModule.'''

        return isinstance(module, AnsibleModule)

    # /class validations ------------------------------------------- }}}

    # class properties --------------------------------------------- {{{
    @property
    def module(self):
        return self._module

    @module.setter
    def module(self, module):
        if not self.valid_module(module):
            self._module = None
            self.failed = True
            self.message = 'Invalid module: {0}.'.format(module)
            raise HomebrewException(self.message)

        else:
            self._module = module
            return module

    @property
    def path(self):
        return self._path

    @path.setter
    def path(self, path):
        if not self.valid_path(path):
            self._path = []
            self.failed = True
            self.message = 'Invalid path: {0}.'.format(path)
            raise HomebrewException(self.message)

        else:
            if isinstance(path, basestring):
                self._path = path.split(':')
            else:
                self._path = path

            return path

    @property
    def brew_path(self):
        return self._brew_path

    @brew_path.setter
    def brew_path(self, brew_path):
        if not self.valid_brew_path(brew_path):
            self._brew_path = None
            self.failed = True
            self.message = 'Invalid brew_path: {0}.'.format(brew_path)
            raise HomebrewException(self.message)

        else:
            self._brew_path = brew_path
            return brew_path

    @property
    def params(self):
        return self._params

    @params.setter
    def params(self, params):
        self._params = self.module.params
        return self._params

    @property
    def current_package(self):
        return self._current_package

    @current_package.setter
    def current_package(self, package):
        if not self.valid_package(package):
            self._current_package = None
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(package)
            raise HomebrewException(self.message)

        else:
            self._current_package = package
            return package
    # /class properties -------------------------------------------- }}}

    def __init__(self, module, path=None, packages=None, state=None,
                 update_homebrew=False, ):
        self._setup_status_vars()
        self._setup_instance_vars(module=module, path=path, packages=packages,
                                  state=state, update_homebrew=update_homebrew, )

        self._prep()

    # prep --------------------------------------------------------- {{{
    def _setup_status_vars(self):
        self.failed = False
        self.changed = False
        self.changed_count = 0
        self.unchanged_count = 0
        self.message = ''

    def _setup_instance_vars(self, **kwargs):
        for key, val in kwargs.iteritems():
            setattr(self, key, val)

    def _prep(self):
        self._prep_path()
        self._prep_brew_path()

    def _prep_path(self):
        if not self.path:
            self.path = ['/usr/local/bin']

    def _prep_brew_path(self):
        if not self.module:
            self.brew_path = None
            self.failed = True
            self.message = 'AnsibleModule not set.'
            raise HomebrewException(self.message)

        self.brew_path = self.module.get_bin_path(
            'brew',
            required=True,
            opt_dirs=self.path,
        )
        if not self.brew_path:
            self.brew_path = None
            self.failed = True
            self.message = 'Unable to locate homebrew executable.'
            raise HomebrewException('Unable to locate homebrew executable.')

        return self.brew_path

    def _status(self):
        return (self.failed, self.changed, self.message)
    # /prep -------------------------------------------------------- }}}

    def run(self):
        try:
            self._run()
        except HomebrewException:
            pass

        if not self.failed and (self.changed_count + self.unchanged_count > 1):
            self.message = "Changed: %d, Unchanged: %d" % (
                self.changed_count,
                self.unchanged_count,
            )
        (failed, changed, message) = self._status()

        return (failed, changed, message)

    # checks ------------------------------------------------------- {{{
    def _current_package_is_installed(self):
        if not self.valid_package(self.current_package):
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        rc, out, err = self.module.run_command(
            "{brew_path} list -m1 | grep -q '^{package}$'".format(
                brew_path=self.brew_path,
                package=self.current_package,
            )
        )

        if rc == 0:
            return True
        else:
            return False

    def _outdated_packages(self):
        rc, out, err = self.module.run_command([
            self.brew_path,
            'outdated',
        ])
        return [line.split(' ')[0].strip() for line in out.split('\n') if line]

    def _current_package_is_outdated(self):
        if not self.valid_package(self.current_package):
            return False

        return self.current_package in self._outdated_packages()

    def _current_package_is_installed_from_head(self):
        if not Homebrew.valid_package(self.current_package):
            return False
        elif not self._current_package_is_installed():
            return False

        rc, out, err = self.module.run_command([
            self.brew_path,
            'info',
            self.current_package,
        ])

        try:
            version_info = [line for line in out.split('\n') if line][0]
        except IndexError:
            return False

        return version_info.split(' ')[-1] == 'HEAD'
    # /checks ------------------------------------------------------ }}}

    # commands ----------------------------------------------------- {{{
    def _run(self):
        if self.update_homebrew:
            self._update_homebrew()

        if self.packages:
            if self.state == 'installed':
                return self._install_packages()
            elif self.state == 'upgraded':
                return self._upgrade_packages()
            elif self.state == 'head':
                return self._install_packages()
            elif self.state == 'linked':
                return self._link_packages()
            elif self.state == 'unlinked':
                return self._unlink_packages()
            elif self.state == 'absent':
                return self._uninstall_packages()

    # updated -------------------------------- {{{
    def _update_homebrew(self):
        rc, out, err = self.module.run_command([
            self.brew_path,
            'update',
        ])
        if rc == 0:
            if out and isinstance(out, basestring):
                already_updated = any(
                    re.search(r'Already up-to-date.', s.strip(), re.IGNORECASE)
                    for s in out.split('\n')
                    if s
                )
                if not already_updated:
                    self.changed = True
                    self.message = 'Homebrew updated successfully.'
                else:
                    self.message = 'Homebrew already up-to-date.'

            return True
        else:
            self.failed = True
            self.message = err.strip()
            raise HomebrewException(self.message)
    # /updated ------------------------------- }}}

    # installed ------------------------------ {{{
    def _install_current_package(self):
        if not self.valid_package(self.current_package):
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if self._current_package_is_installed():
            self.unchanged_count += 1
            self.message = 'Package already installed: {0}'.format(
                self.current_package,
            )
            return True

        if self.module.check_mode:
            self.changed = True
            self.message = 'Package would be installed: {0}'.format(
                self.current_package
            )
            raise HomebrewException(self.message)

        if self.state == 'head':
            head = '--HEAD'
        else:
            head = None

        cmd = [opt
               for opt in (self.brew_path, 'install', self.current_package, head)
               if opt]

        rc, out, err = self.module.run_command(cmd)

        if self._current_package_is_installed():
            self.changed_count += 1
            self.changed = True
            self.message = 'Package installed: {0}'.format(self.current_package)
            return True
        else:
            self.failed = True
            self.message = err.strip()
            raise HomebrewException(self.message)

    def _install_packages(self):
        for package in self.packages:
            self.current_package = package
            self._install_current_package()

        return True
    # /installed ----------------------------- }}}

    # upgraded ------------------------------- {{{
    def _upgrade_current_package(self):
        command = 'upgrade'

        if not self.valid_package(self.current_package):
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if not self._current_package_is_installed():
            command = 'install'

        if self._current_package_is_installed() and not self._current_package_is_outdated():
            self.message = 'Package is already upgraded: {0}'.format(
                self.current_package,
            )
            self.unchanged_count += 1
            return True

        if self.module.check_mode:
            self.changed = True
            self.message = 'Package would be upgraded: {0}'.format(
                self.current_package
            )
            raise HomebrewException(self.message)

        rc, out, err = self.module.run_command([
            self.brew_path,
            command,
            self.current_package,
        ])

        if not self._current_package_is_outdated():
            self.changed_count += 1
            self.changed = True
            self.message = 'Package upgraded: {0}'.format(self.current_package)
            return True
        else:
            self.failed = True
            self.message = err.strip()
            raise HomebrewException(self.message)

    def _upgrade_all_packages(self):
        rc, out, err = self.module.run_command([
            self.brew_path,
            'upgrade',
        ])
        if rc == 0:
            self.changed = True
            self.message = 'All packages upgraded.'
            return True
        else:
            self.failed = True
            self.message = err.strip()
            raise HomebrewException(self.message)

    def _upgrade_packages(self):
        if not self.packages:
            self._upgrade_all_packages()
        else:
            for package in self.packages:
                self.current_package = package
                self._upgrade_current_package()
            return True
    # /upgraded ------------------------------ }}}

    # uninstalled ---------------------------- {{{
    def _uninstall_current_package(self):
        if not self.valid_package(self.current_package):
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if not self._current_package_is_installed():
            self.unchanged_count += 1
            self.message = 'Package already uninstalled: {0}'.format(
                self.current_package,
            )
            return True

        if self.module.check_mode:
            self.changed = True
            self.message = 'Package would be uninstalled: {0}'.format(
                self.current_package
            )
            raise HomebrewException(self.message)

        cmd = [opt
               for opt in (self.brew_path, 'uninstall', self.current_package)
               if opt]

        rc, out, err = self.module.run_command(cmd)

        if not self._current_package_is_installed():
            self.changed_count += 1
            self.changed = True
            self.message = 'Package uninstalled: {0}'.format(self.current_package)
            return True
        else:
            self.failed = True
            self.message = err.strip()
            raise HomebrewException(self.message)

    def _uninstall_packages(self):
        for package in self.packages:
            self.current_package = package
            self._uninstall_current_package()

        return True
    # /uninstalled ----------------------------- }}}

    # linked --------------------------------- {{{
    def _link_current_package(self):
        if not self.valid_package(self.current_package):
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if not self._current_package_is_installed():
            self.failed = True
            self.message = 'Package not installed: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if self.module.check_mode:
            self.changed = True
            self.message = 'Package would be linked: {0}'.format(
                self.current_package
            )
            raise HomebrewException(self.message)

        cmd = [opt
               for opt in (self.brew_path, 'link', self.current_package)
               if opt]

        rc, out, err = self.module.run_command(cmd)
        self.changed_count += 1
        self.changed = True
        self.message = 'Package linked: {0}'.format(self.current_package)

    def _link_packages(self):
        for package in self.packages:
            self.current_package = package
            self._link_current_package()

        return True
    # /linked -------------------------------- }}}

    # unlinked ------------------------------- {{{
    def _unlink_current_package(self):
        if not self.valid_package(self.current_package):
            self.failed = True
            self.message = 'Invalid package: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if not self._current_package_is_installed():
            self.failed = True
            self.message = 'Package not installed: {0}.'.format(self.current_package)
            raise HomebrewException(self.message)

        if self.module.check_mode:
            self.changed = True
            self.message = 'Package would be unlinked: {0}'.format(
                self.current_package
            )
            raise HomebrewException(self.message)

        cmd = [opt
               for opt in (self.brew_path, 'unlink', self.current_package)
               if opt]

        rc, out, err = self.module.run_command(cmd)
        self.changed_count += 1
        self.changed = True
        self.message = 'Package unlinked: {0}'.format(self.current_package)

    def _unlink_packages(self):
        for package in self.packages:
            self.current_package = package
            self._unlink_current_package()

        return True
    # /unlinked ------------------------------ }}}
    # /commands ---------------------------------------------------- }}}


def main():
    module = AnsibleModule(
        argument_spec=dict(
            name=dict(aliases=["pkg"], required=False),
            path=dict(required=False),
            state=dict(
                default="present",
                choices=[
                    "present", "installed",
                    "latest", "upgraded", "head",
                    "linked", "unlinked",
                    "absent", "removed", "uninstalled",
                ],
            ),
            update_homebrew=dict(
                default="no",
                aliases=["update-brew"],
                type='bool',
            ),
        ),
        supports_check_mode=True,
    )
    p = module.params

    if p['name']:
        packages = p['name'].split(',')
    else:
        packages = None

    path = p['path']
    if path:
        path = path.split(':')
    else:
        path = ['/usr/local/bin']

    state = p['state']
    if state in ('present', 'installed', 'head'):
        state = 'installed'
    if state in ('latest', 'upgraded'):
        state = 'upgraded'
    if state == 'linked':
        state = 'linked'
    if state == 'unlinked':
        state = 'unlinked'
    if state in ('absent', 'removed', 'uninstalled'):
        state = 'absent'

    update_homebrew = p['update_homebrew']

    brew = Homebrew(module=module, path=path, packages=packages,
                    state=state, update_homebrew=update_homebrew)
    (failed, changed, message) = brew.run()
    if failed:
        module.fail_json(msg=message)
    else:
        module.exit_json(changed=changed, msg=message)

# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()