# Copyright (C) 2014-2015  Codethink Limited
#
# 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; version 2 of the License.
#
# 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, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

# This plugin is used as part of the Baserock automated release process.
#
# See: <http://wiki.baserock.org/guides/release-process> for more information.

import csv
import os
import warnings

import cliapp
import morphlib

class SystemManifestsPlugin(cliapp.Plugin):

    def enable(self):
        self.app.add_subcommand(
            'system-manifest', self.manifests,
            arg_synopsis='REPO REF MORPH [MORPH]...')

    def disable(self):
        pass

    def manifests(self, args):
        '''Generate manifest(s) for the given system(s).

        Command line arguments:

        * `REPO` is a git repository URL.
        * `REF` is a branch or other commit reference in that repository.
        * `MORPH` is a system morphology name at that ref.

        '''

        if len(args) < 3:
            raise cliapp.AppException(
                'Wrong number of arguments to system-manifests command '
                '(see help)')

        repo, ref = args[0], args[1]
        system_filenames = map(morphlib.util.sanitise_morphology_path,
                               args[2:])

        self.lrc, self.rrc = morphlib.util.new_repo_caches(self.app)
        self.resolver = morphlib.artifactresolver.ArtifactResolver()

        for system_filename in system_filenames:
            self.system_manifest(repo, ref, system_filename)

    def system_manifest(self, repo, ref, system_filename):
        '''Generate manifest for given system.'''

        self.app.status(
            msg='Creating source pool for %s' % system_filename, chatty=True)
        source_pool = morphlib.sourceresolver.create_source_pool(
            self.lrc, self.rrc, repo, ref, system_filename,
            cachedir=self.app.settings['cachedir'],
            update_repos = not self.app.settings['no-git-update'],
            status_cb=self.app.status)

        self.app.status(
            msg='Resolving artifacts for %s' % system_filename, chatty=True)
        root_artifacts = self.resolver.resolve_root_artifacts(source_pool)

        def find_artifact_by_name(artifacts_list, filename):
            for a in artifacts_list:
                if a.source.filename == filename:
                    return a
            raise ValueError

        system_artifact = find_artifact_by_name(root_artifacts,
                                                system_filename)

        self.app.status(
            msg='Computing cache keys for %s' % system_filename, chatty=True)
        build_env = morphlib.buildenvironment.BuildEnvironment(
            self.app.settings, system_artifact.source.morphology['arch'])
        ckc = morphlib.cachekeycomputer.CacheKeyComputer(build_env)

        aliases = self.app.settings['repo-alias']
        resolver = morphlib.repoaliasresolver.RepoAliasResolver(aliases)

        manifest = Manifest(system_filename)

        for source in set(a.source for a in system_artifact.walk()):
            source.cache_key = ckc.compute_key(source)
            source.cache_id = ckc.get_cache_id(source)

            if source.morphology['kind'] != 'chunk':
                continue

            name = source.morphology['name']
            ref = source.original_ref

            # Ensure we have a cache of the repo
            if not self.lrc.has_repo(source.repo_name):
                self.lrc.cache_repo(source.repo_name)

            cached = self.lrc.get_repo(source.repo_name)

            manifest.add_chunk(name, ref, cached)

def get_main_license(dir): # pragma: no cover
    license = 'UNKNOWN'
    if os.path.exists(dir + '/COPYING'):
        license_file = dir + '/COPYING'
    elif os.path.exists(dir + '/LICENSE'):
        license_file = dir + '/LICENSE'
    else:
        return license

    # TODO: Some sensible place to get this functionality from
    licensecheck_path = os.path.join(os.getcwd(),
                                     'scripts/licensecheck.pl')
    output = cliapp.runcmd(['perl', licensecheck_path, '-l',
                            '500' , license_file])
    if output is not None:
        license = output[(len(license_file) + 2):].strip()

    return license

def get_all_licenses(dir): # pragma: no cover
    license_list = 'UNKNOWN'
    # TODO: Return list of all unique licenses used in all the files
    #       in the directroy tree provided

    return license_list

class Manifest:
    """
    Writes out a manifest of what's included in a system
    """

    def __init__(self, system_name):
        path = os.path.join(os.getcwd(), system_name + '-manifest.csv')
        print('Creating {}'.format(path))
        self.file = open(path, 'wb')
        self.writer = csv.writer(self.file, quoting=csv.QUOTE_ALL)

    def _write_chunk(self, chunk_name, version_guess,
                     license, license_list, upstream):
        self.writer.writerow([chunk_name, version_guess,
                              license, license_list, upstream])

    def add_chunk(self, chunk_name, ref, cached_repo):
        print('  Inspecting chunk: {}'.format(chunk_name))
        version_guess = cached_repo.version_guess(ref)
        # TODO: Clone cached repo into temp dir
        license = None#get_main_license(dir)
        license_list = None#get_all_licenses(dir)
        upstream = None#get_upstream_address(dir)
        self._write_chunk(chunk_name, version_guess, license,
                          license_list, upstream)