#!/usr/bin/env python2
# Copyright 2016  Lars Wirzenius
#
# 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/>.
#
# =*= License: GPL-3+ =*=


import re
import time

import cliapp

import bumperlib


class Bumper(cliapp.Application):

    def process_args(self, args):
        project_name = self.get_project_name()
        version = self.get_version(args)
        print 'Releasing {} version {}'.format(project_name, version)

        current_version = self.get_current_version()
        if not self.version_is_newer(version, current_version):
            raise cliapp.AppException(
                'New version {} is older than current version {}'.format(
                    version, current_version))

        version_py = self.find_version_py()
        print '... {}'.format(version_py)
        self.write_version_py(version_py, version, '')

        print '... debian/changelog'
        self.update_debian_changelog(version, 'New upstream version.')
        self.release_debian_changelog()

        print '... NEWS'
        self.update_NEWS_for_release(version)

        print '... git commit'
        self.commit(version, 'Prepare to release version {}'.format(version))

        print '... git tag'
        self.make_release_tag(version)

        gitversion = version + '+git'
        print 'Updating in-development version to', gitversion

        print '... {}'.format(version_py)
        self.write_version_py(version_py, version, '+git')

        print '... debian/changelog'
        self.update_debian_changelog(gitversion, '')

        print '... NEWS'
        self.update_NEWS_for_git(gitversion)

        print '... git commit'
        self.commit(
            version,
            'Bump version number post-release to {}'.format(gitversion))

    def get_version(self, args):
        if len(args) != 1:
            raise cliapp.AppException('Need exactly one argument, the version')
        return args[0]

    def find_version_py(self):
        output = cliapp.runcmd(['git', 'ls-files'])
        filenames = [x.strip() for x in output.splitlines()]
        version_pys = [x for x in filenames if x.endswith('/version.py')]
        if len(version_pys) == 0:
            raise cliapp.AppException('No version.py in project')
        elif len(version_pys) > 1:
            raise cliapp.AppException('Too many version.py in project')
        return version_pys[0]

    def get_current_version(self):
        return cliapp.runcmd(['python', 'setup.py', '--version']).strip()

    def version_is_newer(self, v1, v2):
        '''Is v1 newer than v2?'''
        vi1 = self.parse_version_info(v1, None)
        vi2 = self.parse_version_info(v2, None)
        returncode, out, err = cliapp.runcmd_unchecked(
            ['dpkg', '--compare-versions', v1, 'gt', v2])
        return returncode == 0

    def update_debian_changelog(self, version, msg):
        debian_version = '{}-1'.format(version)
        cliapp.runcmd(['dch', '-v', debian_version, msg])

    def release_debian_changelog(self):
        cliapp.runcmd(['dch', '-r', ''])

    def update_NEWS_for_release(self, version):
        with open('NEWS') as f:
            text = f.read()
        date = time.strftime('%Y-%m-%d')
        pattern = r'^Version \d+(\.\d+)*(\+git)?, not yet released$'
        replacement = 'Version {}, released {}'.format(version, date)
        updated = re.sub(pattern, replacement, text, count=1, flags=re.M)
        with open('NEWS', 'w') as f:
            f.write(updated)

    def update_NEWS_for_git(self, version):
        with open('NEWS') as f:
            text = f.read()
        pattern = r'^Version \d+(\.\d+)*, released \d\d\d\d-\d\d-\d\d$'
        replacement = 'Version {}, not yet released'.format(version)
        match = re.search(pattern, text, flags=re.M)
        if not match:
            raise cliapp.AppException('No place to insert new entry in NEWS')
        before, after = text[:match.start()], text[match.start():]
        with open('NEWS', 'w') as f:
            f.write(before)
            f.write(replacement + '\n')
            f.write('-' * len(replacement))
            f.write('\n\n\n')
            f.write(after)

    def commit(self, version, msg):
        cliapp.runcmd(['git', 'commit', '-am', msg])

    def make_release_tag(self, version):
        name = self.get_project_name()
        tag_name = '{}-{}'.format(name, version)
        msg = 'Release version {}'.format(version)
        cliapp.runcmd(['git', 'tag', '-sam', msg, tag_name])

    def get_project_name(self):
        output = cliapp.runcmd(['python', 'setup.py', '--name'])
        return output.strip()

    def write_version_py(self, filename, version, suffix):
        version_info = self.parse_version_info(version, suffix)
        with open(filename, 'w') as f:
            f.write('__version__ = "{}"\n'.format(version + suffix))
            f.write('__version_info__ = {!r}\n'.format(version_info))

    def parse_version_info(self, version, suffix):
        parts = version.split('.')
        result = []
        for part in parts:
            try:
                result.append(int(part))
            except ValueError:
                result.append(part)
        if suffix:
            result.append(suffix)
        return tuple(result)


Bumper(version=bumperlib.__version__).run()