#!/usr/bin/python2
#
# post-receive-notify-updates
#
# Copyright (C) 2008  Owen Taylor
# Copyright (C) 2009  Red Hat, Inc
# Copyright (C) 2009  Frederic Peters
#
# 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 2
# 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, If not, see
# http://www.gnu.org/licenses/.
#
# About
# =====
# This script is used to send out notification mails on branch updates; these
# notification mails are typically used to trigger automated rebuilds
#

import re
import os
import pwd
import sys

script_path = os.path.realpath(os.path.abspath(sys.argv[0]))
script_dir = os.path.dirname(script_path)

sys.path.insert(0, script_dir)

from git import *
from util import die, strip_string as s, start_email, end_email

# These addresses always get notified
ALL_MODULE_RECIPIENTS = []

BRANCH_RE = re.compile(r'^refs/heads/(.*)$')
def get_branch_name(refname):
    m = BRANCH_RE.match(refname)
    if m:
        return m.group(1)

SPLIT_RE = re.compile("\s*,\s*")

def main():
    module_name = get_module_name()

    try:
        recipients_s = git.config("hooks.update-recipients", _quiet=True)
    except CalledProcessError:
        recipients_s = ""

    recipients_s = recipients_s.strip()
    if recipients_s == "":
        recipients = []
    else:
        recipients = SPLIT_RE.split(recipients_s)

    for recipient in ALL_MODULE_RECIPIENTS:
        if not recipient in recipients:
            recipients.append(recipient)

    changes = []

    if len(sys.argv) > 1:
        # For testing purposes, allow passing in a ref update on the command line
        if len(sys.argv) != 4:
            die("Usage: post-receive-notify-updates OLDREV NEWREV REFNAME")
        branch_name = get_branch_name(sys.argv[3])
        if branch_name is not None:
            changes.append((branch_name, sys.argv[1], sys.argv[2], sys.argv[3]))
    else:
        for line in sys.stdin:
            items = line.strip().split()
            if len(items) != 3:
                die("Input line has unexpected number of items")
            branch_name = get_branch_name(items[2])
            if branch_name is not None:
                changes.append((branch_name, items[0], items[1], items[2]))

    if len(changes) == 0:
        # Nothing to mail about
        return

    branches = [branch_name for branch_name, _, _, _ in changes]
    subject = module_name + " " + " ".join(branches)

    if recipients:
        out = start_email()

        print >>out, s("""
To: %(recipients)s
From: noreply@entrouvert.org
Subject: %(subject)s
""") % {
                'recipients': ", ".join(recipients),
                'subject': subject
           }
    
        # Trailing newline to signal the end of the header
        print >>out
    
        for _, oldrev, newrev, refname in changes:
            print >>out, oldrev, newrev, refname
    
        end_email()

if __name__ == '__main__':
    main()