from __future__ import annotations

from collections.abc import Generator
from pathlib import Path
from unittest.mock import patch

import pygit2
import pytest
from fastapi import FastAPI
from fastapi.testclient import TestClient

from pygittools.merge import MR_REF_PREFIX, MergeRequest
from pygitweb.auth_config import AuthConfig, LocalUser
from pygitweb.config import settings
from pygitweb.conftest import client_as_user
from pygitweb.merge_requests import merge_router
from pygitweb.permissions import Permission, PermissionsMap, permission_key


def _commit_chain(repo: pygit2.Repository) -> tuple[pygit2.Oid, pygit2.Oid]:
	sig = pygit2.Signature("tester", "tester@example.com")
	tb = repo.TreeBuilder()
	tree = tb.write()
	a = repo.create_commit(None, sig, sig, "a", tree, [])
	repo.create_reference("refs/heads/main", a)
	b = repo.create_commit(None, sig, sig, "b", tree, [a])
	return a, b


_MR_AUTH = AuthConfig(
	auth_mode="local",
	local_users=[LocalUser(user="creator", password="secret"), LocalUser(user="merger", password="secret")],
	oauth_permissions=PermissionsMap.model_validate({
		"*": [],
		permission_key(Permission.MR_CREATE, "demo"): ["creator"],
		permission_key(Permission.MR_MERGE, "demo"): ["merger"],
	}),
)


def _build_client() -> TestClient:
	app = FastAPI()
	app.include_router(merge_router, prefix="/mr")
	return TestClient(app)


@pytest.fixture
def mr_env(tmp_path: Path) -> Generator[dict[str, str], None, None]:
	root = tmp_path / "mr-perms"
	root.mkdir()
	repo_dir = root / "demo"
	repo_dir.mkdir()
	repo = pygit2.init_repository(str(repo_dir), bare=False)
	_a, b = _commit_chain(repo)
	mr = MergeRequest(
		b,
		repo.default_signature,
		ours="refs/heads/main",
		title="Feature MR",
		name=f"{MR_REF_PREFIX}aaaabbbbccccdddd",
	)
	mr_oid = mr.write(repo)
	projects_list = root / "projects.list"
	projects_list.write_text("demo tester\n", encoding="utf-8")
	with (
		patch.object(settings, "PROJECTROOT", str(root)),
		patch.object(settings, "PROJECTS_LIST", str(projects_list)),
		patch.object(settings, "STRICT_EXPORT", False),
		patch.object(settings, "EXPORT_OK", ""),
		patch("pygitweb.auth_config.auth_config", _MR_AUTH),
		patch("pygitweb.auth.auth_config", _MR_AUTH),
	):
		yield {
			"client": _build_client(),
			"project": "demo",
			"mr_tag_oid": str(mr_oid),
			"tip_b": str(b),
		}


def test_mr_ff_open_when_auth_disabled(mr_env: dict[str, str]) -> None:
	client = mr_env["client"]
	assert isinstance(client, TestClient)
	with patch.object(settings, "AUTH", False):
		r = client.post(
			"/mr/ff",
			params={"project": mr_env["project"], "h": mr_env["mr_tag_oid"]},
			follow_redirects=False,
		)
	assert r.status_code == 303


def test_mr_create_401_without_login(mr_env: dict[str, str]) -> None:
	client = mr_env["client"]
	assert isinstance(client, TestClient)
	with patch.object(settings, "AUTH", True):
		r = client.post(
			"/mr/create",
			data={
				"project": mr_env["project"],
				"theirs": "refs/heads/main",
				"ours": "refs/heads/main",
				"title": "MR",
			},
			follow_redirects=False,
		)
	assert r.status_code == 401


def test_mr_create_forbidden_without_create_grant(mr_env: dict[str, str]) -> None:
	client = mr_env["client"]
	assert isinstance(client, TestClient)
	with patch.object(settings, "AUTH", True), client_as_user(client, "merger"):
		r = client.post(
			"/mr/create",
			data={
				"project": mr_env["project"],
				"theirs": "refs/heads/main",
				"ours": "refs/heads/main",
				"title": "MR",
			},
			follow_redirects=False,
		)
	assert r.status_code == 403


def test_mr_ff_forbidden_without_merge_grant(mr_env: dict[str, str]) -> None:
	client = mr_env["client"]
	assert isinstance(client, TestClient)
	with patch.object(settings, "AUTH", True), client_as_user(client, "creator"):
		r = client.post(
			"/mr/ff",
			params={"project": mr_env["project"], "h": mr_env["mr_tag_oid"]},
			follow_redirects=False,
		)
	assert r.status_code == 403


def test_mr_ff_allowed_with_merge_grant(mr_env: dict[str, str]) -> None:
	client = mr_env["client"]
	assert isinstance(client, TestClient)
	with patch.object(settings, "AUTH", True), client_as_user(client, "merger"):
		r = client.post(
			"/mr/ff",
			params={"project": mr_env["project"], "h": mr_env["mr_tag_oid"]},
			follow_redirects=False,
		)
	assert r.status_code == 303