"""T42: drawer guest add/remove + render.

The drawer grows a "Guest" section (when a guest bot is present in the
chat), a "Group" section sourced from the ``group_node`` row, an
"Add guest" form (visible while no guest is present), and a "Remove
guest" button (visible while one is). The two new POST endpoints emit
``guest_added`` / ``guest_removed`` events plus ancillary updates:

* ``POST /chats/{chat_id}/drawer/guest/add`` runs the relationship-seed
  classifier (T38) over the user-supplied prose and emits an
  ``edge_update`` per direction when the seed comes back non-default.
  It also seeds a ``group_node_initialized`` row when none exists yet.
* ``POST /chats/{chat_id}/drawer/guest/remove`` first emits
  ``scene_closed`` for the active scene so the host -> you scene closes
  cleanly before the guest leaves.
"""

from __future__ import annotations

import json
from pathlib import Path

import pytest
from fastapi.testclient import TestClient

from chat.app import app
from chat.db.connection import open_db
from chat.eventlog.log import append_event
from chat.eventlog.projector import project
from chat.llm.mock import MockLLMClient


@pytest.fixture
def client(tmp_path, monkeypatch):
    cfg = tmp_path / "config.toml"
    cfg.write_text('featherless_api_key = "test"\n')
    monkeypatch.setenv("CHAT_CONFIG_PATH", str(cfg))
    db = tmp_path / "test.db"
    monkeypatch.setenv("CHAT_DB_PATH", str(db))
    with TestClient(app) as c:
        if hasattr(app.state, "background_worker"):
            app.state.background_worker.enabled = False
        yield c


def _bot_payload(bot_id: str, name: str) -> dict:
    return {
        "id": bot_id,
        "name": name,
        "persona": "...",
        "voice_samples": [],
        "traits": [],
        "backstory": "",
        "initial_relationship_to_you": "",
        "kickoff_prose": "",
    }


def _seed_chat(db: Path, *, with_scene: bool = True) -> None:
    """Seed a chat hosted by ``bot_a`` (with ``bot_b`` authored as a
    candidate guest) and, by default, an open scene so the
    ``guest_removed`` flow has something to close.
    """
    with open_db(db) as conn:
        append_event(conn, kind="bot_authored", payload=_bot_payload("bot_a", "BotA"))
        append_event(conn, kind="bot_authored", payload=_bot_payload("bot_b", "BotB"))
        append_event(
            conn,
            kind="you_authored",
            payload={"name": "Me", "pronouns": "they/them", "persona": ""},
        )
        append_event(
            conn,
            kind="chat_created",
            payload={
                "id": "chat_bot_a",
                "host_bot_id": "bot_a",
                "initial_time": "2026-04-26T20:00:00+00:00",
                "narrative_anchor": "Day 1",
                "weather": "",
            },
        )
        if with_scene:
            append_event(
                conn,
                kind="scene_opened",
                payload={
                    "chat_id": "chat_bot_a",
                    "container_id": None,
                    "started_at": "2026-04-26T20:00:00+00:00",
                    "participants": ["you", "bot_a"],
                },
            )
        project(conn)


def _override_llm(canned: list[str]):
    """Wire a ``MockLLMClient`` into the drawer's LLM dependency."""
    from chat.web.kickoff import get_llm_client

    app.dependency_overrides[get_llm_client] = lambda: MockLLMClient(
        canned=list(canned)
    )


def test_drawer_no_guest_omits_guest_section(client, tmp_path):
    _seed_chat(tmp_path / "test.db")
    response = client.get("/chats/chat_bot_a/drawer")
    assert response.status_code == 200
    body = response.text
    # No guest-section header; the "Add guest" form should be visible instead.
    assert "<h3>Guest</h3>" not in body
    assert "Add guest" in body


def test_drawer_add_guest_seeds_edges_and_group_node(client, tmp_path):
    _seed_chat(tmp_path / "test.db")
    canned = json.dumps(
        {
            "a_to_b_summary": "old college friend",
            "a_to_b_knowledge_facts": ["studied physics together"],
            "a_to_b_affinity_delta": 4,
            "a_to_b_trust_delta": -1,
            "b_to_a_summary": "former roommate",
            "b_to_a_knowledge_facts": ["lived together junior year"],
            "b_to_a_affinity_delta": 3,
            "b_to_a_trust_delta": 0,
        }
    )
    _override_llm([canned])
    try:
        response = client.post(
            "/chats/chat_bot_a/drawer/guest/add",
            data={
                "guest_bot_id": "bot_b",
                "relationship_prose": (
                    "Alice and Bob met in college and studied physics together."
                ),
            },
        )
        assert response.status_code == 200
    finally:
        app.dependency_overrides.clear()

    with open_db(tmp_path / "test.db") as conn:
        from chat.state.edges import get_edge
        from chat.state.group_node import get_group_node
        from chat.state.world import get_chat

        chat = get_chat(conn, "chat_bot_a")
        assert chat["guest_bot_id"] == "bot_b"

        edge_a_to_b = get_edge(conn, "bot_a", "bot_b")
        edge_b_to_a = get_edge(conn, "bot_b", "bot_a")
        # Seed deltas applied around the 50/50 default.
        assert edge_a_to_b["affinity"] == 54
        assert edge_a_to_b["trust"] == 49
        assert "studied physics together" in edge_a_to_b["knowledge"]
        assert edge_b_to_a["affinity"] == 53
        assert edge_b_to_a["trust"] == 50
        assert "lived together junior year" in edge_b_to_a["knowledge"]

        group = get_group_node(conn, "chat_bot_a")
        assert group is not None
        assert set(group["members"]) == {"you", "bot_a", "bot_b"}


def test_drawer_add_guest_empty_prose_skips_edge_update(client, tmp_path):
    _seed_chat(tmp_path / "test.db")
    # No canned responses: the seed function short-circuits on empty prose
    # so no LLM call should happen.
    _override_llm([])
    try:
        response = client.post(
            "/chats/chat_bot_a/drawer/guest/add",
            data={"guest_bot_id": "bot_b", "relationship_prose": "   "},
        )
        assert response.status_code == 200
    finally:
        app.dependency_overrides.clear()

    with open_db(tmp_path / "test.db") as conn:
        from chat.state.world import get_chat

        chat = get_chat(conn, "chat_bot_a")
        assert chat["guest_bot_id"] == "bot_b"

        # guest_added fires but no edge_update events between bot_a and bot_b.
        added = conn.execute(
            "SELECT COUNT(*) FROM event_log WHERE kind = 'guest_added'"
        ).fetchone()[0]
        assert added == 1

        edge_updates = conn.execute(
            "SELECT payload_json FROM event_log WHERE kind = 'edge_update'"
        ).fetchall()
        for (payload_json,) in edge_updates:
            payload = json.loads(payload_json)
            pair = {payload.get("source_id"), payload.get("target_id")}
            assert pair != {"bot_a", "bot_b"}, (
                "no edge_update should be emitted between host and guest "
                "when prose is empty"
            )


def test_drawer_add_guest_when_already_present_returns_400(client, tmp_path):
    _seed_chat(tmp_path / "test.db")
    # Pre-attach a guest directly via append_and_apply so we don't replay
    # the prior chat_created (which would violate UNIQUE on chats.id).
    from chat.eventlog.log import append_and_apply

    with open_db(tmp_path / "test.db") as conn:
        append_and_apply(
            conn,
            kind="bot_authored",
            payload=_bot_payload("bot_c", "BotC"),
        )
        append_and_apply(
            conn,
            kind="guest_added",
            payload={"chat_id": "chat_bot_a", "guest_bot_id": "bot_b"},
        )

    _override_llm([])
    try:
        response = client.post(
            "/chats/chat_bot_a/drawer/guest/add",
            data={"guest_bot_id": "bot_c", "relationship_prose": ""},
        )
        assert response.status_code == 400
    finally:
        app.dependency_overrides.clear()


def test_drawer_remove_guest_clears_and_closes_scene(client, tmp_path):
    _seed_chat(tmp_path / "test.db")
    from chat.eventlog.log import append_and_apply

    with open_db(tmp_path / "test.db") as conn:
        append_and_apply(
            conn,
            kind="guest_added",
            payload={"chat_id": "chat_bot_a", "guest_bot_id": "bot_b"},
        )

    response = client.post("/chats/chat_bot_a/drawer/guest/remove")
    assert response.status_code == 200

    with open_db(tmp_path / "test.db") as conn:
        from chat.state.world import active_scene, get_chat

        chat = get_chat(conn, "chat_bot_a")
        assert chat["guest_bot_id"] is None
        assert active_scene(conn, "chat_bot_a") is None

        kinds = [
            row[0]
            for row in conn.execute(
                "SELECT kind FROM event_log ORDER BY id"
            ).fetchall()
        ]
        # scene_closed must precede guest_removed in the log.
        assert "scene_closed" in kinds
        assert "guest_removed" in kinds
        assert kinds.index("scene_closed") < kinds.index("guest_removed")


def test_drawer_with_guest_renders_guest_and_group_sections(client, tmp_path):
    _seed_chat(tmp_path / "test.db")
    from chat.eventlog.log import append_and_apply

    with open_db(tmp_path / "test.db") as conn:
        append_and_apply(
            conn,
            kind="guest_added",
            payload={"chat_id": "chat_bot_a", "guest_bot_id": "bot_b"},
        )
        # Activity for the guest so the section has content to render.
        append_and_apply(
            conn,
            kind="activity_change",
            payload={
                "entity_id": "bot_b",
                "posture": "leaning",
                "action": {"verb": "smirking"},
                "attention": "BotA",
            },
        )
        # Edges in all four directions involving the guest.
        for src, tgt in (("bot_a", "bot_b"), ("bot_b", "bot_a"), ("you", "bot_b"), ("bot_b", "you")):
            append_and_apply(
                conn,
                kind="edge_update",
                payload={
                    "source_id": src,
                    "target_id": tgt,
                    "chat_id": "chat_bot_a",
                    "affinity_delta": 1,
                },
            )
        append_and_apply(
            conn,
            kind="group_node_initialized",
            payload={
                "chat_id": "chat_bot_a",
                "members": ["you", "bot_a", "bot_b"],
                "summary": "Three friends catching up over drinks.",
                "dynamic": "warm and conspiratorial",
            },
        )

    response = client.get("/chats/chat_bot_a/drawer")
    assert response.status_code == 200
    body = response.text
    assert "<h3>Guest</h3>" in body
    assert "BotB" in body
    assert "smirking" in body
    assert "<h3>Group</h3>" in body
    assert "Three friends catching up over drinks." in body
    assert "warm and conspiratorial" in body
    # "Remove guest" button is visible when a guest is present.
    assert "Remove guest" in body