# Copyright (C) 2019 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import abc
import os
import random
import string

import git

from . import abstract


class AbstractPushAction(abstract.AbstractAction):
    def __init__(self, refspec, project_name, probability=0.2):
        super().__init__(url=None, user=None, pwd=None, probability=probability)
        self.project_name = project_name
        self.change_types = [self._add_file, self._modify_file, self._delete_file]
        self.local_repo_path = os.path.join("/tmp", self.project_name)
        self.repo = git.Repo(self.local_repo_path)
        self.refspec = refspec

    @abc.abstractmethod
    def _prepare(self):
        pass

    def _execute_action(self):
        self.repo.git.checkout("origin/master")
        self._prepare()
        if os.path.exists(self.local_repo_path):
            num_commits = random.randint(1, 5)
            for _ in range(num_commits):
                self._create_commit()
            self.repo.remotes.origin.push(refspec=self.refspec)
            self.was_executed = True
            self._log_result(
                "Pushed %d commits to project %s using refspec %s"
                % (num_commits, self.project_name, self.refspec)
            )

    def _create_commit(self):
        change_type_choice = random.choice(self.change_types)
        change_type_choice()
        self.repo.index.commit("%s\n\n" % self._create_random_string(16))

    def _add_file(self):
        while True:
            file_name = self._create_random_string(8)
            file_path = os.path.join("/tmp", self.project_name, file_name)
            if os.path.exists(file_path):
                continue
            with open(file_path, "w+") as f:
                self.log.info("Adding file %s to commit", file_name)
                f.write(self._create_random_string(random.randint(1, 2000)))
            self.repo.index.add([file_name])
            break

    def _modify_file(self):
        files = self._get_files_in_repo_workdir()
        if not files:
            self.log.info(
                "Repository does not contain any files yet. Adding instead of modifying"
            )
            self._add_file()
            return
        file_name = random.choice(files)
        file_path = os.path.join("/tmp", self.project_name, file_name)
        with open(file_path, "a+") as f:
            self.log.info("Modifying file %s for commit", file_name)
            f.write(self._create_random_string(random.randint(1, 2000)))
        self.repo.index.add([file_name])

    def _delete_file(self):
        files = self._get_files_in_repo_workdir()
        if not files:
            self.log.info(
                "Repository does not contain any files yet. Adding instead of deleting"
            )
            self._add_file()
            return
        file_name = random.choice(files)
        self.log.info("Deleting file %s to commit", file_name)
        os.remove(os.path.join("/tmp", self.project_name, file_name))
        self.repo.index.remove([file_name])

    def _get_files_in_repo_workdir(self):
        files = list()
        for (dirpath, _, filenames) in os.walk(os.path.join("/tmp", self.project_name)):
            if ".git" not in dirpath:
                files += [os.path.join(dirpath, file) for file in filenames]
        return files

    @staticmethod
    def _create_random_string(length):
        allowed_symbols = string.ascii_letters + string.digits
        return "".join([random.choice(allowed_symbols) for n in range(length)])