#! /usr/bin/env python2

"""Progit specific hook to add comment on issues if the commits fixes or

relates to an issue.

"""

import os

import re

import sys

import subprocess

FIXES = [

    re.compile('fixe[sd]?:? #(\d+)', re.I),

    re.compile('.*\s+fixe[sd]?:? #(\d+)', re.I),

    re.compile('fixe[sd]?:? https?://.*/(\w+)/issue/(\d+)', re.I),

    re.compile('.*\s+fixe[sd]?:? https?://.*/(\w+)/issue/(\d+)', re.I),

]

RELATES = [

    re.compile('relate[sd]?:? #(\d+)', re.I),

    re.compile('.*\s+relate[sd]?:? #(\d+)', re.I),

    re.compile('relate[sd]?:? https?://.*/(\w+)/issue/(\d+)', re.I),

    re.compile('.*\s+relate[sd]?:? https?://.*/(\w+)/issue/(\d+)', re.I),

]

def read_git_output(args, input=None, keepends=False, **kw):

    """Read the output of a Git command."""

    return read_output(['git'] + args, input=input, keepends=keepends, **kw)

def read_git_lines(args, keepends=False, **kw):

    """Return the lines output by Git command.

    Return as single lines, with newlines stripped off."""

    return read_git_output(args, keepends=True, **kw).splitlines(keepends)

def read_output(cmd, input=None, keepends=False, **kw):

    if input:

        stdin = subprocess.PIPE

    else:

        stdin = None

    p = subprocess.Popen(

        cmd, stdin=stdin, stdout=subprocess.PIPE, stderr=subprocess.PIPE, **kw

        )

    (out, err) = p.communicate(input)

    retcode = p.wait()

    if retcode:

        print 'ERROR: %s =-- %s' % (cmd, retcode)

    if not keepends:

        out = out.rstrip('\n\r')

    return out

def generate_revision_change_log(new_commits_list):

    print 'Detailed log of new commits:\n\n'

    for line in read_git_lines(

            ['log', '--no-walk']

            + new_commits_list

            + ['--'],

            keepends=False,

        ):

        print '*', line

        for motif in FIXES:

            if motif.match(line):

                print 'fixes', motif.match(line).groups()

        for motif in RELATES:

            if motif.match(line):

                print 'relates to', motif.match(line).groups()

def get_commits_id(fromrev, torev):

    ''' Retrieve the list commit between two revisions and return the list

    of their identifier.

    '''

    cmd = ['rev-list', '%s...%s' %(torev, fromrev)]

    return read_git_lines(cmd)

def get_repo_name():

    ''' Return the name of the git repo based on its path.

    '''

    repo = os.path.basename(os.getcwd()).split('.git')[0]

    return repo

def get_pusher():

    ''' Return the name of the person that pushed the commit. '''

    return os.environ.get('GL_USER', os.environ.get('USER', 'unknown user'))

def run_as_post_receive_hook():

    changes = []

    for line in sys.stdin:

        print line

        (oldrev, newrev, refname) = line.strip().split(' ', 2)

        print '  -- Old rev'

        print oldrev

        print '  -- New rev'

        print newrev

        print '  -- Ref name'

        print refname

        generate_revision_change_log(get_commits_id(oldrev, newrev))

    print 'repo:', get_repo_name()

def main(args):

        run_as_post_receive_hook()

if __name__ == '__main__':

    main(sys.argv[1:])