"""Tests for gateway /compress user-facing messaging."""

from datetime import datetime
from unittest.mock import MagicMock, patch

import pytest

from gateway.config import GatewayConfig, Platform, PlatformConfig
from gateway.platforms.base import MessageEvent
from gateway.session import SessionEntry, SessionSource, build_session_key


def _make_source() -> SessionSource:
    return SessionSource(
        platform=Platform.TELEGRAM,
        user_id="u1",
        chat_id="c1",
        user_name="tester",
        chat_type="dm",
    )


def _make_event(text: str = "/compress") -> MessageEvent:
    return MessageEvent(text=text, source=_make_source(), message_id="m1")


def _make_history() -> list[dict[str, str]]:
    return [
        {"role": "user", "content": "one"},
        {"role": "assistant", "content": "two"},
        {"role": "user", "content": "three"},
        {"role": "assistant", "content": "four"},
    ]


def _make_runner(history: list[dict[str, str]]):
    from gateway.run import GatewayRunner

    runner = object.__new__(GatewayRunner)
    runner.config = GatewayConfig(
        platforms={Platform.TELEGRAM: PlatformConfig(enabled=True, token="***")}
    )
    session_entry = SessionEntry(
        session_key=build_session_key(_make_source()),
        session_id="sess-1",
        created_at=datetime.now(),
        updated_at=datetime.now(),
        platform=Platform.TELEGRAM,
        chat_type="dm",
    )
    runner.session_store = MagicMock()
    runner.session_store.get_or_create_session.return_value = session_entry
    runner.session_store.load_transcript.return_value = history
    runner.session_store.rewrite_transcript = MagicMock()
    runner.session_store.update_session = MagicMock()
    runner.session_store._save = MagicMock()
    runner._session_db = None
    return runner


@pytest.mark.asyncio
async def test_compress_command_reports_noop_without_success_banner():
    history = _make_history()
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (list(history), "")

    def _estimate(messages, **_kwargs):
        assert messages == history
        return 100

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "test-key"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    assert "No changes from compression" in result
    assert "Compressed:" not in result
    assert "Approx request size: ~100 tokens (unchanged)" in result
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_explains_when_token_estimate_rises():
    history = _make_history()
    compressed = [
        history[0],
        {"role": "assistant", "content": "Dense summary that still counts as more tokens."},
        history[-1],
    ]
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (compressed, "")

    def _estimate(messages, **_kwargs):
        if messages == history:
            return 100
        if messages == compressed:
            return 120
        raise AssertionError(f"unexpected transcript: {messages!r}")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "test-key"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    assert "Compressed: 4 → 3 messages" in result
    assert "Approx request size: ~100 → ~120 tokens" in result
    assert "denser summaries" in result
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_appends_warning_when_compression_aborts():
    """When the auxiliary summariser fails and the compressor ABORTS (returns
    messages unchanged), /compress must append a visible ⚠️ warning to its
    reply telling the user nothing was dropped and how to retry. Otherwise
    the failure is silently logged and the user has no idea why nothing
    happened."""
    history = _make_history()
    # Abort path: compressor returns the input messages unchanged.
    compressed = list(history)
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    # Simulate compression aborting (force=True bypassed cooldown but the
    # aux LLM is genuinely broken).
    agent_instance.context_compressor._last_compress_aborted = True
    agent_instance.context_compressor._last_summary_fallback_used = False
    agent_instance.context_compressor._last_summary_dropped_count = 0
    agent_instance.context_compressor._last_summary_error = (
        "404 model not found: gemini-3-flash-preview"
    )
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (compressed, "")

    def _estimate(messages, **_kwargs):
        if messages == history:
            return 100
        if messages == compressed:
            return 100
        raise AssertionError(f"unexpected transcript: {messages!r}")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "***"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    # A clearly-marked warning must be appended.
    assert "⚠️" in result
    assert "Compression aborted" in result
    # Underlying error must surface so users can fix their config.
    assert "404 model not found" in result
    # User must be told nothing was dropped — the whole point of the
    # new behavior is no silent data loss.
    assert "No messages were dropped" in result
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_surfaces_aux_model_failure_even_when_recovered():
    """When the user's configured ``auxiliary.compression.model`` errors out
    but compression recovers by retrying on the main model, /compress must
    STILL inform the user.  Silent recovery hides broken config the user
    needs to fix."""
    history = _make_history()
    # Compressed transcript — normal successful compression, no placeholder.
    compressed = [
        history[0],
        {"role": "assistant", "content": "summary via main model"},
        history[-1],
    ]
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    # Fallback placeholder was NOT used — recovery succeeded.
    agent_instance.context_compressor._last_compress_aborted = False
    agent_instance.context_compressor._last_summary_fallback_used = False
    agent_instance.context_compressor._last_summary_dropped_count = 0
    agent_instance.context_compressor._last_summary_error = None
    # But the configured aux model DID fail before the retry succeeded.
    agent_instance.context_compressor._last_aux_model_failure_model = (
        "gemini-3-flash-preview"
    )
    agent_instance.context_compressor._last_aux_model_failure_error = (
        "404 model not found: gemini-3-flash-preview"
    )
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (compressed, "")

    def _estimate(messages, **_kwargs):
        if messages == history:
            return 100
        if messages == compressed:
            return 60
        raise AssertionError(f"unexpected transcript: {messages!r}")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "***"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    # Compression succeeded
    assert "Compressed:" in result
    # No ⚠️ warning (that's reserved for dropped-turns case)
    assert "⚠️" not in result
    # But there IS an info note about the broken aux model
    assert "ℹ️" in result
    assert "gemini-3-flash-preview" in result
    assert "404" in result
    assert "auxiliary.compression.model" in result
    # The user's context is explicitly called out as intact
    assert "intact" in result
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_passes_session_db_and_persists_rotated_session():
    """session_db must be wired into the /compress temp agent so that
    _compress_context can actually rotate the session and persist the
    compressed transcript — without it compression is a silent no-op."""
    history = _make_history()
    compressed = [
        history[0],
        {"role": "assistant", "content": "compressed summary"},
        history[-1],
    ]
    runner = _make_runner(history)
    runner._session_db = object()
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance.compression_in_place = False
    agent_instance.session_id = "sess-1"

    def _compress(messages, *_args, **_kwargs):
        agent_instance.session_id = "sess-2"
        return compressed, ""

    agent_instance._compress_context.side_effect = _compress

    def _estimate(messages, **_kwargs):
        if messages == history:
            return 100
        if messages == compressed:
            return 60
        raise AssertionError(f"unexpected transcript: {messages!r}")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "***"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance) as mock_agent_cls,
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    assert "Compressed:" in result
    mock_agent_cls.assert_called_once()
    assert mock_agent_cls.call_args.kwargs["session_db"] is runner._session_db
    runner.session_store._save.assert_called_once()
    runner.session_store.rewrite_transcript.assert_called_once_with(
        "sess-2", compressed
    )
    runner.session_store.update_session.assert_called_once_with(
        build_session_key(_make_source()), last_prompt_tokens=0
    )
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_does_not_repoint_session_when_transcript_write_fails():
    """If the canonical transcript write fails after compression produces a new
    continuation session_id, /compress must NOT repoint the live session onto
    that empty session_id, and must report the failure instead of a success
    banner. Otherwise a transient DB/IO error during compression would silently
    drop the user's active conversation while still claiming success."""
    history = _make_history()
    compressed = [
        history[0],
        {"role": "assistant", "content": "summary"},
        history[-1],
    ]
    runner = _make_runner(history)
    runner._session_db = object()
    session_entry = runner.session_store.get_or_create_session.return_value
    # Simulate the canonical DB write failing (lock contention, ENOSPC, ...).
    runner.session_store.rewrite_transcript = MagicMock(return_value=False)
    # Telegram topic re-binding must never run on the failure path.
    runner._sync_telegram_topic_binding = MagicMock()

    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance._last_compaction_in_place = False
    agent_instance.session_id = "sess-1"

    def _compress(messages, *_args, **_kwargs):
        # Compression rotated the session: the agent now holds a NEW session_id.
        agent_instance.session_id = "sess-2"
        return compressed, ""

    agent_instance._compress_context.side_effect = _compress

    def _estimate(messages, **_kwargs):
        return 100

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "***"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    # The user sees a failure banner, not a success banner.
    assert "failed" in result.lower()
    assert "Compressed:" not in result
    # The live session was NOT repointed onto the empty new session_id, so the
    # original conversation stays reachable.
    assert session_entry.session_id == "sess-1"
    runner.session_store._save.assert_not_called()
    runner._sync_telegram_topic_binding.assert_not_called()
    # Resources are still cleaned up even though the command errored.
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_in_place_skips_destructive_rewrite():
    """In-place compaction (compression.in_place / #38763) persists via
    archive_and_compact() inside _compress_context — the previous active rows
    are soft-archived and the compacted set inserted. Calling
    rewrite_transcript() afterwards would invoke
    replace_messages(active_only=False), DELETEing the just-archived rows
    (silent data loss, #61145). The handler must skip the rewrite and still
    report success."""
    history = _make_history()
    compressed = [
        history[0],
        {"role": "assistant", "content": "compacted summary"},
        history[-1],
    ]
    runner = _make_runner(history)
    runner._session_db = object()
    session_entry = runner.session_store.get_or_create_session.return_value
    runner.session_store.rewrite_transcript = MagicMock()

    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    # In-place compaction: session_id is UNCHANGED but marked as a success.
    agent_instance._last_compaction_in_place = True
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (compressed, "")

    def _estimate(messages, **_kwargs):
        if messages == history:
            return 100
        if messages == compressed:
            return 60
        raise AssertionError(f"unexpected transcript: {messages!r}")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "***"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", side_effect=_estimate),
    ):
        result = await runner._handle_compress_command(_make_event())

    assert "Compressed:" in result
    # The destructive rewrite must NOT run — archive_and_compact() already
    # persisted, and rewrite_transcript would wipe the archived rows.
    runner.session_store.rewrite_transcript.assert_not_called()
    assert session_entry.session_id == "sess-1"
    agent_instance.shutdown_memory_provider.assert_called_once()
    agent_instance.close.assert_called_once()


@pytest.mark.asyncio
async def test_compress_command_preserves_platform_and_gateway_session_key():
    """The temporary compression agent must carry the originating source's
    platform and stable gateway session key, matching a normal gateway turn.
    Without them ``_session_source_for_agent`` falls back to a default "cli"
    host source, so an external context engine misattributes the retained
    transcript tail and later duplicates it on resume (#50422)."""
    history = _make_history()
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (list(history), "")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "test-key"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance) as mock_agent,
        patch("agent.model_metadata.estimate_request_tokens_rough", return_value=100),
    ):
        await runner._handle_compress_command(_make_event())

    assert mock_agent.call_count == 1
    _, kwargs = mock_agent.call_args
    # Platform preserved as the live turn's config key (TELEGRAM -> "telegram"),
    # not the unbound "cli"/"local" fallback.
    assert kwargs.get("platform") == "telegram"
    # Stable gateway session key preserved, identical to a normal gateway turn.
    assert kwargs.get("gateway_session_key") == runner._session_key_for_source(_make_source())
    assert kwargs["gateway_session_key"]


@pytest.mark.asyncio
async def test_compress_command_overrides_stale_resolver_identity():
    """If the resolver already supplies platform/gateway_session_key, the
    construction must (a) not raise "got multiple values for keyword argument",
    and (b) let the originating-source identity win — a stale/placeholder
    resolver value must not defeat the attribution fix."""
    history = _make_history()
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (list(history), "")

    # Resolver injects a WRONG platform and a stale session key.
    runtime = {"api_key": "test-key", "platform": "discord", "gateway_session_key": "stale-key"}
    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value=runtime),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance) as mock_agent,
        patch("agent.model_metadata.estimate_request_tokens_rough", return_value=100),
    ):
        await runner._handle_compress_command(_make_event())  # must not raise

    assert mock_agent.call_count == 1
    _, kwargs = mock_agent.call_args
    # Source-derived identity overrides the stale resolver values, passed once.
    assert kwargs["platform"] == "telegram"
    assert kwargs["gateway_session_key"] == runner._session_key_for_source(_make_source())


@pytest.mark.asyncio
async def test_compress_command_passes_tool_messages_to_compressor():
    """Tool results must reach _compress_context (#3854).

    Filtering the transcript to user/assistant-only starved the
    compressor's tool-result pruning — tool messages are usually the bulk
    of the context.
    """
    history = [
        {"role": "user", "content": "run it"},
        {
            "role": "assistant",
            "content": None,
            "tool_calls": [{"id": "t1", "type": "function",
                            "function": {"name": "x", "arguments": "{}"}}],
        },
        {"role": "tool", "content": "BIG RESULT " * 50, "tool_call_id": "t1"},
        {"role": "assistant", "content": "done"},
        {"role": "user", "content": "thanks"},
        {"role": "assistant", "content": "np"},
    ]
    runner = _make_runner(history)
    agent_instance = MagicMock()
    agent_instance.shutdown_memory_provider = MagicMock()
    agent_instance.close = MagicMock()
    agent_instance._cached_system_prompt = ""
    agent_instance.tools = None
    agent_instance.context_compressor.has_content_to_compress.return_value = True
    agent_instance.session_id = "sess-1"
    agent_instance._compress_context.return_value = (list(history), "")

    with (
        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "test-key"}),
        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
        patch("run_agent.AIAgent", return_value=agent_instance),
        patch("agent.model_metadata.estimate_request_tokens_rough", return_value=100),
    ):
        await runner._handle_compress_command(_make_event())

    args, _kwargs = agent_instance._compress_context.call_args
    passed = args[0]
    roles = [m.get("role") for m in passed]
    assert "tool" in roles, f"tool messages filtered out: {roles}"
    # Assistant tool_calls stubs (content=None) must survive too, or the
    # tool message would dangle without its call.
    assert any(m.get("tool_calls") for m in passed), "assistant tool_calls stub dropped"
