# Copyright (c) 2024 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import os
import sys

from typing import Dict, List, Optional
from unittest import mock
import unittest

# This is to be able to import scm from the root of the repo.
sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

import scm


def GIT(test: unittest.TestCase,
        config: Optional[Dict[str, List[str]]] = None,
        branchref: Optional[str] = None):
    """Installs fakes/mocks for scm.GIT so that:

      * Initial git config (local scope) is set to `config`.
      * GetBranch will just return a fake branchname starting with the value of
        branchref.
      * git_new_branch.create_new_branch will be mocked to update the value
        returned by GetBranch.

    NOTE: The dependency on git_new_branch.create_new_branch seems pretty
    circular - this functionality should probably move to scm.GIT?
    """
    _branchref = [branchref or 'refs/heads/main']

    initial_state = {}
    if config is not None:
        initial_state['local'] = config

    def _newBranch(branchref):
        _branchref[0] = branchref

    patches: List[mock._patch] = [
        mock.patch(
            'scm.GIT._new_config_state',
            side_effect=lambda root: scm.GitConfigStateTest(initial_state)),
        mock.patch('scm.GIT.GetBranchRef',
                   side_effect=lambda _root: _branchref[0]),
        mock.patch('git_new_branch.create_new_branch', side_effect=_newBranch)
    ]

    for p in patches:
        p.start()
        test.addCleanup(p.stop)

    test.addCleanup(scm.GIT.drop_config_cache)