#! /usr/bin/env python2

"""Progit specific hook to update tickets stored in the database based on

the information pushed in the tickets git repository.

"""

import os

import re

import sys

import subprocess

# We need to access the database

if 'PROGIT_CONFIG' not in os.environ \

        and os.path.exists('/etc/progit/progit.cfg'):

    print 'Using configuration file `/etc/progit/progit.cfg`'

    os.environ['PROGIT_CONFIG'] = '/etc/progit/progit.cfg'

sys.path.insert(0, os.path.expanduser('~/repos/gitrepo/progit'))

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 get_files_to_load(new_commits_list):

    print 'Files changed by new commits:\n\n'

    file_list = []

    for line in read_git_lines(

            ['show', '--pretty="format:"', '--name-only', '-r']

            + new_commits_list,

            keepends=False,

        ):

        if line.strip():

            file_list.append(line.strip())

    return file_list

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 run_as_post_receive_hook():

    file_list = set()

    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

        file_list.union(

            set(get_files_to_load(get_commits_id(oldrev, newrev))))

    for filename in file_list:

        print 'To load: %s' % filename

    print 'repo:', get_repo_name()

def main(args):

        run_as_post_receive_hook()

if __name__ == '__main__':

    main(sys.argv[1:])