#!/usr/bin/python

#

# Gerrit Launchpad and CIA Hook, inspired by:

#   https://github.com/hobbs/jirret

#   http://cia.vc/clients/git/ciabot.bash

#   http://cia.vc/clients/bzr/cia_bzr.py

#

# Copyright (C) 2011, 2012 Catalyst IT (http://www.catalyst.net.nz)

#

# This program 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 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 General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from email.mime.text import MIMEText

from getopt import getopt

import re

import smtplib

import subprocess

import sys

from xml.dom.minidom import Document

import xmlrpclib

FROM_ADDRESS = 'dev@mahara.org'

TO_ADDRESS_SUFFIX = '@bugs.launchpad.net'

CIA_PROJECT = 'Mahara'

CIA_SERVER = 'http://cia.vc'

BASE_DIR = '/home/gerrit/mahara_reviews'

def send_notifications(change_url, project, branch, submitter, commit):

    # Extract git log of all merged commits

    git_log = subprocess.Popen(['git', '--git-dir=' + BASE_DIR + '/git/' + project + '.git', 'log', '--no-merges', commit + '^1..' + commit], stdout=subprocess.PIPE).communicate()[0]

    # Find bug numbers referenced in the git log

    bug_regexp = '[Bb]ug:? *#?([0-9]+)'

    tokens = re.split(bug_regexp, git_log)

    # Extract unique bug numbers

    bugs = []

    for token in tokens:

        if re.match('^\d+$', token) and (token not in bugs):

            bugs.append(token)

            send_bug_mail(token, change_url, project, commit, submitter, branch, git_log)

    submit_to_cia(project, commit, branch, git_log)

def send_bug_mail(bug_number, change_url, project, commit, submitter, branch, git_log):

    to_address = bug_number + TO_ADDRESS_SUFFIX

    gitorious_url = 'http://gitorious.org/mahara/%s/commit/%s' % (project, commit)

    body = '''Reviewed:  %s

Committed: %s

Submitter: %s

Branch:    %s\n''' % (change_url, gitorious_url, submitter, branch)

    msg = MIMEText(body + '\n' + git_log)

    msg['Subject'] = 'A change has been merged'

    msg['From'] = FROM_ADDRESS

    msg['To'] = to_address

    s = smtplib.SMTP()

    s.connect()

    s.sendmail(FROM_ADDRESS, [to_address], msg.as_string())

    s.quit()

def append_commit(commits, document, project, full_commit_id, author, log):

    if not full_commit_id or not author:

        return

    revision = subprocess.Popen(['git', '--git-dir=' + BASE_DIR + '/git/' + project + '.git', 'rev-parse', '--short', full_commit_id], stdout=subprocess.PIPE).communicate()[0].strip()

    gitorious_url = 'http://gitorious.org/mahara/%s/commit/%s' % (project, full_commit_id)

    commit = document.createElement('commit')

    commit_author = document.createElement('author')

    commit_author.appendChild(document.createTextNode(author))

    commit.appendChild(commit_author)

    commit_revision = document.createElement('revision')

    commit_revision.appendChild(document.createTextNode(revision))

    commit.appendChild(commit_revision)

    commit_log = document.createElement('log')

    commit_log.appendChild(document.createTextNode(log))

    commit.appendChild(commit_log)

    commit_url = document.createElement('url')

    commit_url.appendChild(document.createTextNode(gitorious_url))

    commit.appendChild(commit_url)

    commits.append(commit)

def generate_commits(document, project, git_log):

    commits = []

    commit_id = author = log = None

    for line in git_log.splitlines():

        if line.startswith('commit'):

            append_commit(commits, document, project, commit_id, author, log)

            commit_id = line[7:]

            author = log = None

        elif line.startswith('Author:'):

            full_author = line[8:]

            author = re.search('^(.+) <[^>]+>$', full_author).group(1)

        elif line.startswith('    ') and not log:

            log = line[4:]

    append_commit(commits, document, project, commit_id, author, log)

    return commits

def submit_to_cia(project, commit, branch, git_log):

    doc = Document()

    message = doc.createElement('message')

    generator = doc.createElement('generator')

    generator_name = doc.createElement('name')

    generator_name.appendChild(doc.createTextNode('Mahara custom CIA script'))

    generator_version = doc.createElement('version')

    generator_version.appendChild(doc.createTextNode('1.0'))

    generator_url = doc.createElement('url')

    generator_url.appendChild(doc.createTextNode('http://gitorious.org/mahara/mahara-scripts/blobs/master/change-merged'))

    generator.appendChild(generator_name)

    generator.appendChild(generator_version)

    generator.appendChild(generator_url)

    message.appendChild(generator)

    source = doc.createElement('source')

    source_project = doc.createElement('project')

    source_project.appendChild(doc.createTextNode(CIA_PROJECT))

    source_branch = doc.createElement('branch')

    source_branch.appendChild(doc.createTextNode(branch))

    source.appendChild(source_project)

    source.appendChild(source_branch)

    message.appendChild(source)

    body = doc.createElement('body')

    message.appendChild(body)

    doc.appendChild(message)

    for commit in generate_commits(doc, project, git_log):

        body.appendChild(commit)

        xmlrpclib.ServerProxy(CIA_SERVER).hub.deliver(doc.toxml())

        body.removeChild(commit)

def main():

    # https://gerrit.googlecode.com/svn/documentation/2.1.6/config-hooks.html#change-merged

    gerrit_args = ['change=', 'change-url=', 'project=', 'branch=', 'submitter=', 'commit=']

    args, unused = getopt(sys.argv[1:], '', gerrit_args)

    change_url = project = branch = submitter = commit = None

    for argname, argv in args:

        if argname == '--change-url':

            change_url = argv

        elif argname == '--project':

            project = argv

        elif argname == '--branch':

            branch = argv

        elif argname == '--submitter':

            submitter = argv

        elif argname == '--commit':

            commit = argv

    if change_url and project and branch and submitter and commit:

        send_notifications(change_url, project, branch, submitter, commit)

    else:

        print 'Missing arguments'

	return 1

    return 0;

if __name__ == '__main__':

    sys.exit(main())