"""
Regression tests for GitHub issue #789.

Bug: every brand-new session immediately disappeared from the sidebar because
all_sessions() filtered out sessions where title == 'Untitled' AND
message_count == 0. Since every new session starts with those values, it was
filtered out of /api/sessions on the next refresh.

Fix: exempt sessions younger than 60 seconds from that filter. Sessions older
than 60 seconds that are still Untitled with 0 messages are still suppressed
(ghost sessions from test runs / accidental reloads).
"""
import json
import time

import pytest

import api.models as models
from api.models import Session, all_sessions


@pytest.fixture(autouse=True)
def _isolate(tmp_path, monkeypatch):
    """Redirect SESSION_DIR and SESSION_INDEX_FILE to a temp dir."""
    session_dir = tmp_path / "sessions"
    session_dir.mkdir()
    index_file = session_dir / "_index.json"

    monkeypatch.setattr(models, "SESSION_DIR", session_dir)
    monkeypatch.setattr(models, "SESSION_INDEX_FILE", index_file)

    models.SESSIONS.clear()
    yield
    models.SESSIONS.clear()


def _make_untitled_session(age_seconds, messages=None, session_id=None):
    """Create a Session with title='Untitled', updated_at set to age_seconds ago."""
    now = time.time()
    s = Session(
        session_id=session_id or None,
        title="Untitled",
        messages=messages or [],
        updated_at=now - age_seconds,
        created_at=now - age_seconds,
    )
    # Persist to disk so the full-scan fallback can also find it
    s.path.write_text(
        json.dumps(s.__dict__, ensure_ascii=False, indent=2), encoding="utf-8"
    )
    return s


def _make_titled_session(age_seconds, session_id=None):
    """Create a Session with a real title and one message."""
    now = time.time()
    s = Session(
        session_id=session_id or None,
        title="My conversation",
        messages=[{"role": "user", "content": "hello"}],
        updated_at=now - age_seconds,
        created_at=now - age_seconds,
    )
    s.path.write_text(
        json.dumps(s.__dict__, ensure_ascii=False, indent=2), encoding="utf-8"
    )
    return s


# ── Test 1: brand-new Untitled 0-message session IS included ─────────────────

def test_new_untitled_session_is_visible_in_sidebar():
    """A session created just now (0 seconds old) must appear in all_sessions()."""
    new_session = _make_untitled_session(age_seconds=0)

    result = all_sessions()
    ids = {s["session_id"] for s in result}

    assert new_session.session_id in ids, (
        "Brand-new Untitled 0-message session must be visible in the sidebar "
        "(fix for issue #789)"
    )


def test_recent_untitled_session_under_60s_is_visible():
    """A session 30 seconds old should still be visible."""
    recent_session = _make_untitled_session(age_seconds=30)

    result = all_sessions()
    ids = {s["session_id"] for s in result}

    assert recent_session.session_id in ids, (
        "Untitled 0-message session younger than 60 s must be visible (#789)"
    )


# ── Test 2: old Untitled 0-message session IS still filtered ─────────────────

def test_old_untitled_session_over_60s_is_filtered():
    """A ghost session (Untitled, 0 messages, >60 s old) must be hidden."""
    old_session = _make_untitled_session(age_seconds=120)

    result = all_sessions()
    ids = {s["session_id"] for s in result}

    assert old_session.session_id not in ids, (
        "Ghost Untitled 0-message session older than 60 s must be filtered out"
    )


def test_session_exactly_at_boundary_is_filtered():
    """A session just over 60 seconds old should be filtered."""
    boundary_session = _make_untitled_session(age_seconds=61)

    result = all_sessions()
    ids = {s["session_id"] for s in result}

    assert boundary_session.session_id not in ids, (
        "Untitled 0-message session older than 60 s must be filtered out"
    )


# ── Test 3: session with messages is always visible regardless of age ─────────

def test_session_with_messages_always_visible_new():
    """A session with messages (even Untitled) is always visible when new."""
    s = Session(
        title="Untitled",
        messages=[{"role": "user", "content": "hello"}],
    )
    s.path.write_text(
        json.dumps(s.__dict__, ensure_ascii=False, indent=2), encoding="utf-8"
    )

    result = all_sessions()
    ids = {r["session_id"] for r in result}
    assert s.session_id in ids, "Session with messages must always appear in sidebar"


def test_session_with_messages_always_visible_old():
    """An old session with messages is always visible."""
    now = time.time()
    s = Session(
        title="Untitled",
        messages=[{"role": "user", "content": "hello"}],
        updated_at=now - 3600,
        created_at=now - 3600,
    )
    s.path.write_text(
        json.dumps(s.__dict__, ensure_ascii=False, indent=2), encoding="utf-8"
    )

    result = all_sessions()
    ids = {r["session_id"] for r in result}
    assert s.session_id in ids, (
        "Old session with messages must always appear in sidebar"
    )


def test_titled_session_with_no_messages_old_is_visible():
    """A titled session with 0 messages (old) should not be filtered — filter
    only targets Untitled sessions."""
    now = time.time()
    s = Session(
        title="Project Alpha",
        messages=[],
        updated_at=now - 3600,
        created_at=now - 3600,
    )
    s.path.write_text(
        json.dumps(s.__dict__, ensure_ascii=False, indent=2), encoding="utf-8"
    )

    result = all_sessions()
    ids = {r["session_id"] for r in result}
    assert s.session_id in ids, (
        "A titled session must always appear regardless of message count"
    )


# ── Test 4: mixed bag — only old Untitled empty sessions are filtered ─────────

def test_mixed_sessions_correct_visibility():
    """With a mix of sessions, only old+Untitled+empty ones are suppressed."""
    new_ghost = _make_untitled_session(age_seconds=5, session_id="new_ghost")
    old_ghost = _make_untitled_session(age_seconds=200, session_id="old_ghost")
    real_session = _make_titled_session(age_seconds=500, session_id="real_session")

    result = all_sessions()
    ids = {s["session_id"] for s in result}

    assert "new_ghost" in ids, "New Untitled session (5s old) must be visible"
    assert "old_ghost" not in ids, "Old Untitled session (200s old) must be hidden"
    assert "real_session" in ids, "Titled session with messages must be visible"