import base64
import hashlib
import os
from pathlib import Path

import pytest

import syncvito.updater as updater
from syncvito.updater import GiteaUpdateService, UpdateFormatError, UpdateInfo, parse_version


class FakeResponse:
    def __init__(self, payload: bytes, url: str = "https://gitea.example/asset") -> None:
        self.payload = payload
        self.offset = 0
        self.headers = {"Content-Length": str(len(payload))}
        self.url = url

    def __enter__(self) -> "FakeResponse":
        return self

    def __exit__(self, *_args: object) -> bool:
        return False

    def read(self, size: int = -1) -> bytes:
        if size < 0:
            size = len(self.payload) - self.offset
        chunk = self.payload[self.offset : self.offset + size]
        self.offset += len(chunk)
        return chunk

    def geturl(self) -> str:
        return self.url


def _release(version: str, *, prerelease: bool = False) -> dict[str, object]:
    installer = f"SyncVitoSetup-{version}.exe"
    return {
        "tag_name": f"v{version}",
        "name": f"SyncVito {version}",
        "body": "Änderungen",
        "html_url": f"https://gitea.example/releases/v{version}",
        "draft": False,
        "prerelease": prerelease,
        "assets": [
            {
                "name": installer,
                "browser_download_url": f"https://gitea.example/download/{installer}",
                "size": 1234,
            },
            {
                "name": f"{installer}.sha256",
                "browser_download_url": f"https://gitea.example/download/{installer}.sha256",
                "size": 96,
            },
        ],
    }


def _info(version: str = "1.1.0") -> UpdateInfo:
    installer = f"SyncVitoSetup-{version}.exe"
    return UpdateInfo(
        version=version,
        title=f"SyncVito {version}",
        notes="Änderungen",
        release_url=f"https://gitea.example/releases/v{version}",
        installer_name=installer,
        download_url=f"https://gitea.example/download/{installer}",
        checksum_url=f"https://gitea.example/download/{installer}.sha256",
        size=0,
    )


def test_parse_version_accepts_stable_tags() -> None:
    assert parse_version("v1.2.3") == (1, 2, 3)
    assert parse_version("10.20.30") == (10, 20, 30)


def test_parse_version_rejects_prerelease() -> None:
    with pytest.raises(ValueError):
        parse_version("1.2.3-beta")


def test_check_reads_latest_installer_release(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    service = GiteaUpdateService("1.0.0", base_url="https://gitea.example", update_directory=tmp_path)
    monkeypatch.setattr(service, "_read_json", lambda _url: _release("1.3.0"))

    update = service.check()

    assert update is not None
    assert update.version == "1.3.0"
    assert update.installer_name == "SyncVitoSetup-1.3.0.exe"


def test_check_returns_none_for_current_version(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    service = GiteaUpdateService("1.3.0", base_url="https://gitea.example", update_directory=tmp_path)
    monkeypatch.setattr(service, "_read_json", lambda _url: _release("1.3.0"))

    assert service.check() is None


def test_release_requires_matching_installer(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    service = GiteaUpdateService("1.0.0", base_url="https://gitea.example", update_directory=tmp_path)
    release = _release("1.1.0")
    release["assets"] = []
    monkeypatch.setattr(service, "_read_json", lambda _url: release)

    with pytest.raises(UpdateFormatError, match="SyncVitoSetup-1.1.0.exe"):
        service.check()


def test_download_verifies_checksum(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    service = GiteaUpdateService("1.0.0", base_url="https://gitea.example", update_directory=tmp_path)
    payload = b"MZ-syncvito-installer"
    digest = hashlib.sha256(payload).hexdigest()
    responses = iter(
        [
            FakeResponse(f"{digest} *SyncVitoSetup-1.1.0.exe\n".encode()),
            FakeResponse(payload),
        ]
    )
    monkeypatch.setattr(service, "_request", lambda *_args, **_kwargs: next(responses))
    progress: list[tuple[int, str]] = []

    result = service.download(_info(), lambda value, text: progress.append((value, text)))

    assert result.read_bytes() == payload
    assert progress[-1][0] == 100


def test_cleanup_removes_only_managed_installers(tmp_path: Path) -> None:
    service = GiteaUpdateService("1.0.0", base_url="https://gitea.example", update_directory=tmp_path)
    managed = [tmp_path / "SyncVitoSetup-1.0.1.exe", tmp_path / "SyncVitoSetup-1.0.2.exe.part"]
    preserved = [tmp_path / "anderes-setup.exe", tmp_path / "SyncVitoSetup-neu.exe"]
    for path in managed + preserved:
        path.write_bytes(b"test")

    assert service.cleanup_installers() == (2, 0)
    assert all(not path.exists() for path in managed)
    assert all(path.exists() for path in preserved)


def test_update_watcher_waits_before_installer(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    installer = tmp_path / "SyncVitoSetup-1.1.0.exe"
    bootstrap_log = tmp_path / "bootstrap.log"
    captured: dict[str, object] = {}

    def capture(executable: str, arguments: list[str]) -> None:
        captured["executable"] = executable
        captured["arguments"] = arguments

    monkeypatch.setattr(updater, "_start_detached", capture)
    monkeypatch.setattr(updater.os, "name", "nt")
    powershell = Path(os.environ.get("SYSTEMROOT", r"C:\Windows")) / "System32/WindowsPowerShell/v1.0/powershell.exe"
    monkeypatch.setattr(Path, "is_file", lambda self: self == powershell)

    updater._start_installer_after_exit(installer, ["/VERYSILENT"], [222, 111], bootstrap_log)

    arguments = captured["arguments"]
    assert isinstance(arguments, list)
    encoded = arguments[arguments.index("-EncodedCommand") + 1]
    script = base64.b64decode(encoded).decode("utf-16-le")
    assert "foreach ($processId in @(111, 222))" in script
    assert script.index("while (Get-Process") < script.index(str(installer))
    assert "'/VERYSILENT'" in script