#! /usr/bin/env python2


"""Pagure specific hook to add comment on issues if the commits fixes or
relates to an issue.
"""

import os
import re
import sys
import subprocess

from sqlalchemy.exc import SQLAlchemyError

if 'PAGURE_CONFIG' not in os.environ \
        and os.path.exists('/etc/pagure/pagure.cfg'):
    print 'Using configuration file `/etc/pagure/pagure.cfg`'
    os.environ['PAGURE_CONFIG'] = '/etc/pagure/pagure.cfg'


import pagure
import pagure.exceptions
import pagure.lib.link


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'
    commitid = None
    for line in read_git_lines(
            ['log', '--no-walk']
            + new_commits_list
            + ['--'],
            keepends=False,):
        if line.startswith('commit'):
            commitid = line.split('commit ')[-1]

        line = line.strip()

        print '*', line
        for issue in pagure.lib.link.get_relation(
                pagure.SESSION, get_repo_name(), get_username(),
                line, 'fixes'):
            fixes_commit(commitid, issue, pagure.APP.config.get('APP_URL'))

        for issue in pagure.lib.link.get_relation(
                pagure.SESSION, get_repo_name(), get_username(),
                line, 'relates'):
            relates_commit(commitid, issue, pagure.APP.config.get('APP_URL'))


def relates_commit(commitid, issue, app_url=None):
    ''' Add a comment to an issue that this commit relates to it. '''

    url = '../%s' % commitid[:8]
    if app_url:
        if app_url.endswith('/'):
            app_url = app_url[:-1]
        project = issue.project.path.split('.git')[0]
        if issue.project.is_fork:
            project = 'fork/%s' % project
        url = '%s/%s/%s' % (app_url, project, commitid[:8])

    comment = ''' Commit [%s](%s) relates to this ticket''' % (
        commitid[:8], url)

    try:
        message = pagure.lib.add_issue_comment(
            pagure.SESSION,
            issue=issue,
            comment=comment,
            user=get_pusher(commitid),
            ticketfolder=pagure.APP.config['TICKETS_FOLDER'],
        )
        pagure.SESSION.commit()
    except pagure.exceptions.PagureException as err:
        print err
    except SQLAlchemyError, err:  # pragma: no cover
        pagure.SESSION.rollback()
        pagure.APP.logger.exception(err)


def fixes_commit(commitid, issue, app_url=None):
    ''' Add a comment to an issue that this commit fixes it and update
    the status if the commit is in the master branch. '''

    url = '../%s' % commitid[:8]
    if app_url:
        if app_url.endswith('/'):
            app_url = app_url[:-1]
        project = issue.project.path.split('.git')[0]
        if issue.project.is_fork:
            project = 'fork/%s' % project
        url = '%s/%s/%s' % (app_url, project, commitid[:8])

    comment = ''' Commit [%s](%s) fixes this ticket''' % (
        commitid[:8], url)

    try:
        message = pagure.lib.add_issue_comment(
            pagure.SESSION,
            issue=issue,
            comment=comment,
            user=get_pusher(commitid),
            ticketfolder=pagure.APP.config['TICKETS_FOLDER'],
        )
        pagure.SESSION.commit()
    except pagure.exceptions.PagureException as err:
        print err
    except SQLAlchemyError, err:  # pragma: no cover
        pagure.SESSION.rollback()
        pagure.APP.logger.exception(err)

    branches = [
        item.replace('* ', '') for item in read_git_lines(
            ['branch', '--contains', commitid],
            keepends=False)
    ]

    if 'master' in branches:
        try:
            pagure.lib.edit_issue(
                pagure.SESSION,
                issue,
                ticketfolder=pagure.APP.config['TICKETS_FOLDER'],
                user=get_pusher(commitid),
                status='Fixed')
            pagure.SESSION.commit()
        except pagure.exceptions.PagureException as err:
            print err
        except SQLAlchemyError, err:  # pragma: no cover
            pagure.SESSION.rollback()
            pagure.APP.logger.exception(err)


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_username():
    ''' Return the username of the git repo based on its path.
    '''
    username = None
    repo = os.path.abspath(os.path.join(os.getcwd(), '..'))
    if pagure.APP.config['FORK_FOLDER'] in repo:
        username = repo.split(pagure.APP.config['FORK_FOLDER'])[1]
    return username


def get_pusher(commit):
    ''' Return the name of the person that pushed the commit. '''
    user = None
    output = read_git_lines(
        ['show', '--pretty=format:"%ae"', commit], keepends=False)
    if output:
        user = output[0].replace('"', '')
    if not user:
        user = os.environ.get('GL_USER', os.environ.get('USER', None))
    return 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()
    print 'user:', get_username()


def main(args):
        run_as_post_receive_hook()


if __name__ == '__main__':
    main(sys.argv[1:])