"""A file the model opened, reaching the panel.

The rule this pins is the one that would fail silently: the `canvas` frame is
guarded on truthiness, so it can never blank itself. An empty one would close
every tab somebody had open -- the "approval card you could press twice" failure
with the sign reversed.
"""

from __future__ import annotations

import json

from sqlalchemy import select

from lembas.db.models import ROLE_ASSISTANT, Chat, Connection, Message, Model
from lembas.services import canvas as canvas_service
from lembas.services import generation as generation_service


def _chat_with_a_reply(db, user_id):
    connection = Connection(name="c", base_url="http://127.0.0.1:1", api_key_encrypted="")
    db.add(connection)
    db.commit()
    db.add(Model(connection_id=connection.id, model_id="m"))
    db.commit()
    chat = Chat(user_id=user_id, model_id="m", connection_id=connection.id)
    db.add(chat)
    db.commit()
    db.add(Message(chat_id=chat.id, role="user", content="Have a look", complete=True))
    db.commit()
    assistant = Message(chat_id=chat.id, role=ROLE_ASSISTANT, content="", complete=False)
    db.add(assistant)
    db.commit()
    return chat.id, assistant.id


def _stub_stream(text: str):
    async def stream_chat(_endpoint, _payload):
        yield {"choices": [{"delta": {"content": text}}]}

    return stream_chat


# --- The frame ------------------------------------------------------------------
def test_the_frame_is_absent_when_nothing_was_opened(db, user_id):
    """Asserted directly, because this is the whole safety property. `reasoning`,
    `tools` and `render` are guarded the same way; `metrics`, `status` and `ask`
    are not, because each of *those* has to be able to clear."""
    generation = generation_service.Generation(chat_id="x", message_id="y")
    assert not generation.canvas.get("tabs")


def test_the_frame_carries_the_whole_strip(db, user_id):
    """Not a delta. A follower attaching mid-reply has no earlier fragments to
    append to, so it gets every tab the reply has touched."""
    from lembas.api.chats import _canvas_tabs

    state: dict = {}
    canvas_service.open_tab(state, {"key": "agent:/a.py", "title": "a.py"}, activate=False)
    canvas_service.open_tab(state, {"key": "agent:/b.py", "title": "b.py"}, activate=False)

    html = _canvas_tabs("chat-1", state)
    assert "a.py" in html
    assert "b.py" in html
    # Out of band, because it belongs to a panel and not to the bubble the
    # stream is writing into.
    assert 'hx-swap-oob="true"' in html
    assert 'id="canvas-tabs"' in html


def test_a_path_with_a_quote_does_not_break_the_strip():
    """The key goes into an hx-vals attribute. `| tojson` rather than quoting by
    hand, or a file called `"` produces vals that do not parse and the tab
    silently stops working."""
    from lembas.api.chats import _canvas_tabs

    state: dict = {}
    canvas_service.open_tab(state, {"key": 'agent:/srv/a"b.py', "title": 'a"b.py'})
    html = _canvas_tabs("chat-1", state)
    assert 'a\\"b.py' in html or "a"b.py" in html


# --- Through the loop -------------------------------------------------------------
async def test_two_reads_in_one_round_both_land(db, user_id, monkeypatch):
    """Seeded once and mutated, not re-read per call: two `file_read`s that each
    read the row would leave only the second."""
    generation = generation_service.Generation(chat_id="x", message_id="y")
    generation.canvas = {"tabs": [], "active": ""}

    for path in ("/srv/a.py", "/srv/b.py"):
        canvas_service.open_tab(
            generation.canvas, {"key": f"agent:{path}", "title": path}, activate=False
        )

    assert [t["key"] for t in generation.canvas["tabs"]] == [
        "agent:/srv/a.py",
        "agent:/srv/b.py",
    ]


async def test_a_reply_writes_its_tabs_onto_the_chat(db, user_id, monkeypatch):
    chat_id, message_id = _chat_with_a_reply(db, user_id)
    monkeypatch.setattr(generation_service, "stream_chat", _stub_stream("Looked."))

    generation = generation_service.Generation(chat_id=chat_id, message_id=message_id)
    await generation_service._run(generation)
    # Nothing was opened, so nothing is written -- and in particular the column
    # is not blanked.
    db.expire_all()
    assert not (db.get(Chat, chat_id).canvas_json or {}).get("tabs")


async def test_a_reply_never_wipes_the_tabs_that_were_already_open(
    db, user_id, monkeypatch
):
    """The snapshot is seeded from the row when the reply begins, so a reply
    that opens nothing writes nothing -- and one that opens something adds to
    what was there rather than replacing it."""
    chat_id, message_id = _chat_with_a_reply(db, user_id)
    monkeypatch.setattr(generation_service, "stream_chat", _stub_stream("Looked."))

    chat = db.get(Chat, chat_id)
    chat.canvas_json = canvas_service.open_tab({}, {"key": f"scratch:{chat_id}"})
    db.commit()

    generation = generation_service.Generation(chat_id=chat_id, message_id=message_id)
    await generation_service._run(generation)

    db.expire_all()
    stored = db.get(Chat, chat_id).canvas_json or {}
    assert [t["key"] for t in stored["tabs"]] == [f"scratch:{chat_id}"]
    assert stored["active"] == f"scratch:{chat_id}"


async def test_the_snapshot_is_seeded_from_the_row(db, user_id, monkeypatch):
    """Seeded once where the chat is already loaded, rather than re-read per
    call -- which is what lets two file reads in one round both land."""
    chat_id, message_id = _chat_with_a_reply(db, user_id)
    monkeypatch.setattr(generation_service, "stream_chat", _stub_stream("Looked."))

    chat = db.get(Chat, chat_id)
    chat.canvas_json = canvas_service.open_tab({}, {"key": f"scratch:{chat_id}"})
    db.commit()

    generation = generation_service.Generation(chat_id=chat_id, message_id=message_id)
    await generation_service._run(generation)

    assert [t["key"] for t in generation.canvas["tabs"]] == [f"scratch:{chat_id}"]


# --- What the runners write ---------------------------------------------------------
def test_the_file_tools_name_the_key_the_same_way_a_person_would():
    """A tab a model opened and one a person opened have to be one tab."""
    from lembas.services.agent import tools as agent_tools
    from lembas.services.agent.session import AgentContext

    agent = AgentContext(chat_id="c", label="Box", project_dir="/srv/app")
    for spelling in ("./main.py", "main.py", "/srv/app/main.py"):
        assert agent_tools._canvas(agent, spelling)["key"] == "agent:/srv/app/main.py"


def test_the_key_matches_the_read_path_set():
    """Both come from `_path_key`. If they could drift, `file_edit`'s "read it
    first" and the canvas would disagree about which file was read."""
    from lembas.services.agent import tools as agent_tools
    from lembas.services.agent.session import AgentContext

    agent = AgentContext(chat_id="c", label="Box", project_dir="/srv/app")
    assert agent_tools._canvas(agent, "./main.py")["key"] == (
        f"agent:{agent_tools._path_key(agent, './main.py')}"
    )


def test_the_swap_target_exists_on_a_streaming_bubble():
    """A frame with nowhere to land is a frame that silently does nothing."""
    from lembas.web.templating import templates

    html = templates.get_template("chat/_message.html").render(
        {
            "message": Message(id="m1", chat_id="c1", role=ROLE_ASSISTANT, content=""),
            "streaming": True,
            "chat": None,
            "user": None,
            "models_by_id": {},
            "bodies": {},
        }
    )
    assert 'sse-swap="canvas"' in html


def test_scratch_write_opens_its_tab(db, user_id):
    """It rides on the same mechanism as the file tools, and for the same
    reason: no new schema and no tokens."""
    from lembas.services.tools import REGISTRY

    tool = REGISTRY["scratch_write"]
    assert tool.family == "scratch"
    # RISK_READ, on plan_update's argument: risk is what a tool does to the
    # world the four modes govern, which is the machine.
    assert tool.risk == "read"


def test_the_event_survives_into_the_stored_transcript():
    """Harmless and mildly useful: `_tool_activity.html` reads named keys."""
    event = {"name": "file_read", "canvas": {"key": "agent:/a.py"}}
    assert json.loads(json.dumps(event))["canvas"]["key"] == "agent:/a.py"


def test_nothing_but_the_chat_row_holds_the_tabs(db, user_id):
    """No table, no cleanup path: the tabs go when the chat does."""
    chat_id, _ = _chat_with_a_reply(db, user_id)
    chat = db.get(Chat, chat_id)
    chat.canvas_json = canvas_service.open_tab({}, {"key": "note:1"})
    db.commit()

    db.delete(chat)
    db.commit()
    assert db.scalar(select(Chat)) is None