from __future__ import annotations

import json
from pathlib import Path
from typing import Any

from yolo_webui import subprocess_runner


class FakeRunner:
    def __init__(self, *, error: Exception | None = None) -> None:
        self.error = error
        self.prepared = False
        self.stop_requested = False

    def prepare_run(self) -> None:
        self.prepared = True

    def request_stop(self) -> None:
        self.stop_requested = True

    def train(self, config: Any, on_event: Any) -> Path:
        if self.error is not None:
            raise self.error
        return Path("/tmp/successful-run")


def _write_config(tmp_path: Path) -> Path:
    config_path = tmp_path / "config.json"
    config_path.write_text(
        json.dumps({"dataset": "dataset.yaml", "model": "model.pt"}),
        encoding="utf-8",
    )
    return config_path


def test_main_returns_zero_after_successful_training(
    monkeypatch: Any, tmp_path: Path, capsys: Any
) -> None:
    runner = FakeRunner()
    monkeypatch.setattr(subprocess_runner, "TrainingRunner", lambda: runner)

    return_code = subprocess_runner.main([str(_write_config(tmp_path))])

    output = capsys.readouterr()
    assert return_code == 0
    assert runner.prepared is True
    assert "__YOLO_WEBUI_READY__" in output.out
    assert "__YOLO_WEBUI_RESULT__:/tmp/successful-run" in output.out
    assert "Traceback" not in output.err


def test_main_returns_one_when_training_raises(
    monkeypatch: Any, tmp_path: Path, capsys: Any
) -> None:
    runner = FakeRunner(error=RuntimeError("training failed"))
    monkeypatch.setattr(subprocess_runner, "TrainingRunner", lambda: runner)

    return_code = subprocess_runner.main([str(_write_config(tmp_path))])

    output = capsys.readouterr()
    assert return_code == 1
    assert "RuntimeError: training failed" in output.err