"""Tests for loop_guard.seed_cycle_result and --pick mode.

The seed fixes the cycle-metrics dead-pipeline bug (#1250):
loop_guard pre-seeds cycle_result.json so cycle_retro.py can always
resolve issue= even when the dispatcher doesn't write the file.
"""

from __future__ import annotations

import json
import sys
from unittest.mock import patch

import pytest
import scripts.loop_guard as lg


@pytest.fixture(autouse=True)
def _isolate(tmp_path, monkeypatch):
    """Redirect loop_guard paths to tmp_path for isolation."""
    monkeypatch.setattr(lg, "QUEUE_FILE", tmp_path / "queue.json")
    monkeypatch.setattr(lg, "IDLE_STATE_FILE", tmp_path / "idle_state.json")
    monkeypatch.setattr(lg, "CYCLE_RESULT_FILE", tmp_path / "cycle_result.json")
    monkeypatch.setattr(lg, "GITEA_API", "http://test:3000/api/v1")
    monkeypatch.setattr(lg, "REPO_SLUG", "owner/repo")


# ── seed_cycle_result ──────────────────────────────────────────────────


def test_seed_writes_issue_and_type(tmp_path):
    """seed_cycle_result writes issue + type to cycle_result.json."""
    item = {"issue": 42, "type": "bug", "title": "Fix the thing", "ready": True}
    lg.seed_cycle_result(item)

    data = json.loads((tmp_path / "cycle_result.json").read_text())
    assert data == {"issue": 42, "type": "bug"}


def test_seed_does_not_overwrite_existing(tmp_path):
    """If cycle_result.json already exists, seed_cycle_result leaves it alone."""
    existing = {"issue": 99, "type": "feature", "tests_passed": 123}
    (tmp_path / "cycle_result.json").write_text(json.dumps(existing))

    lg.seed_cycle_result({"issue": 1, "type": "bug"})

    data = json.loads((tmp_path / "cycle_result.json").read_text())
    assert data["issue"] == 99, "Existing file must not be overwritten"


def test_seed_missing_issue_field(tmp_path):
    """Item with no issue key — seed still writes without crashing."""
    lg.seed_cycle_result({"type": "unknown"})
    data = json.loads((tmp_path / "cycle_result.json").read_text())
    assert data["issue"] is None


def test_seed_default_type_when_absent(tmp_path):
    """Item with no type key defaults to 'unknown'."""
    lg.seed_cycle_result({"issue": 7})
    data = json.loads((tmp_path / "cycle_result.json").read_text())
    assert data["type"] == "unknown"


def test_seed_oserror_is_graceful(tmp_path, monkeypatch, capsys):
    """OSError during seed logs a warning but does not raise."""
    monkeypatch.setattr(lg, "CYCLE_RESULT_FILE", tmp_path / "no_dir" / "cycle_result.json")

    from pathlib import Path

    def failing_mkdir(self, *args, **kwargs):
        raise OSError("no space left")

    monkeypatch.setattr(Path, "mkdir", failing_mkdir)

    # Should not raise
    lg.seed_cycle_result({"issue": 5, "type": "bug"})

    captured = capsys.readouterr()
    assert "WARNING" in captured.out


# ── main() integration ─────────────────────────────────────────────────


def _write_queue(tmp_path, items):
    tmp_path.mkdir(parents=True, exist_ok=True)
    lg.QUEUE_FILE.parent.mkdir(parents=True, exist_ok=True)
    lg.QUEUE_FILE.write_text(json.dumps(items))


def test_main_seeds_cycle_result_when_work_found(tmp_path, monkeypatch):
    """main() seeds cycle_result.json with top queue item on ready queue."""
    _write_queue(tmp_path, [{"issue": 10, "type": "feature", "ready": True}])
    monkeypatch.setattr(lg, "_fetch_open_issue_numbers", lambda: None)

    with patch.object(sys, "argv", ["loop_guard"]):
        rc = lg.main()

    assert rc == 0
    data = json.loads((tmp_path / "cycle_result.json").read_text())
    assert data["issue"] == 10


def test_main_no_seed_when_queue_empty(tmp_path, monkeypatch):
    """main() does not create cycle_result.json when queue is empty."""
    _write_queue(tmp_path, [])
    monkeypatch.setattr(lg, "_fetch_open_issue_numbers", lambda: None)

    with patch.object(sys, "argv", ["loop_guard"]):
        rc = lg.main()

    assert rc == 1
    assert not (tmp_path / "cycle_result.json").exists()


def test_main_pick_mode_prints_issue(tmp_path, monkeypatch, capsys):
    """--pick flag prints the top issue number to stdout."""
    _write_queue(tmp_path, [{"issue": 55, "type": "bug", "ready": True}])
    monkeypatch.setattr(lg, "_fetch_open_issue_numbers", lambda: None)

    with patch.object(sys, "argv", ["loop_guard", "--pick"]):
        rc = lg.main()

    assert rc == 0
    captured = capsys.readouterr()
    # The issue number must appear as a line in stdout
    lines = captured.out.strip().splitlines()
    assert str(55) in lines


def test_main_pick_mode_empty_queue_no_output(tmp_path, monkeypatch, capsys):
    """--pick with empty queue exits 1, doesn't print an issue number."""
    _write_queue(tmp_path, [])
    monkeypatch.setattr(lg, "_fetch_open_issue_numbers", lambda: None)

    with patch.object(sys, "argv", ["loop_guard", "--pick"]):
        rc = lg.main()

    assert rc == 1
    captured = capsys.readouterr()
    # No bare integer line printed
    for line in captured.out.strip().splitlines():
        assert not line.strip().isdigit(), f"Unexpected issue number in output: {line!r}"