from __future__ import annotations

from pathlib import Path

import pytest

from syncgames.config import AgentConfig, GameConfig
from syncgames.errors import StaleWipError
from syncgames.session import end_session, start_session
from syncgames.store import FilesystemStore


@pytest.fixture
def env(tmp_path: Path):
    cfg_root = tmp_path / "cfg"
    games = cfg_root / "games"
    games.mkdir(parents=True)
    native = tmp_path / "native" / "saves"
    native.mkdir(parents=True)
    (native / "slot1.sav").write_bytes(b"v1")

    cfg = AgentConfig(
        device_id="pc-test",
        endpoint_url="",
        store="filesystem",
        ssot_root=tmp_path / "ssot",
        config_root=cfg_root,
        state_root=tmp_path / "state",
    )
    game = GameConfig(
        id="demo",
        name="Demo",
        platform="other",
        paths=[str(native)],
        versions_to_keep=3,
    )
    # seed remote empty then first end will push after start with empty live
    store = FilesystemStore(cfg.ssot_root)
    return cfg, store, game, native


def test_start_end_roundtrip(env):
    cfg, store, game, native = env
    start_session(cfg, store, game)
    (native / "slot1.sav").write_bytes(b"v2-progress")
    meta = end_session(cfg, store, game)
    assert meta.live_hash
    assert store.list_live("demo")


def test_hash_gate_blocks_stale(env):
    cfg, store, game, native = env
    start_session(cfg, store, game)
    (native / "slot1.sav").write_bytes(b"A")
    end_session(cfg, store, game)

    # Simulate stale session with old parent after remote advanced elsewhere
    start_session(cfg, store, game)
    # Mutate remote live out from under us
    lives = list((Path(cfg.ssot_root) / "games" / "demo" / "live").rglob("slot1.sav"))
    assert lives
    lives[0].write_bytes(b"REMOTE-NEWER")
    # Update meta live_hash to mismatch parent
    meta = store.get_meta("demo")
    assert meta
    meta.raw["live_hash"] = "sha256:deadbeef"
    store.put_meta("demo", meta)

    (native / "slot1.sav").write_bytes(b"local-stale-wip")
    with pytest.raises(StaleWipError):
        end_session(cfg, store, game)