"""Provider reasoning-parameter policy for ``AIAgent``.

When ``reasoning`` extra_body is safe to send, LM Studio / Ollama / endpoint-profile capability probes,
``reasoning_content`` echo families, and strict-API tool-call sanitising.
Extracted from ``run_agent.py``; every method resolves through ``AIAgent``'s MRO unchanged.
"""
import logging
import time

from agent.lazy_forward import forward as _forward, forward_static as _forward_static
from agent.message_sanitization import matches_reasoning_echo_family
from utils import base_url_host_matches

# Static OpenRouter fallback when the live /v1/models capability cache is cold.
_OPENROUTER_REASONING_PREFIXES = (
    "deepseek/", "anthropic/", "openai/", "x-ai/", "google/gemini-2", "google/gemma-4",
    "qwen/qwen3", "tencent/hy", "xiaomi/",
)

# Hosts whose reasoning gate core owns: a plugin claiming one in ``hostnames`` never replaces it.
_CORE_REASONING_GATED_HOSTS = ("nousresearch.com", "ai-gateway.vercel.sh", "ollama.com")

# Probe results cache per (model, base_url). Definitive values cache permanently; an
# "unknown" value (empty list / None) caches 60s so a transient failure neither sticks
# for the session nor round-trips every turn.
_PROBE_TTL_S = 60


def _cached_probe(agent, cache_attr: str, probe, unknown, definitive):
    """``probe(model, base_url, api_key)`` once per (model, base_url); ``unknown`` is what a raising probe
    yields, ``definitive(value)`` decides permanent vs 60s TTL."""
    cache = getattr(agent, cache_attr, None)
    if cache is None:
        cache = {}
        setattr(agent, cache_attr, cache)
    key = (agent.model, agent.base_url)
    cached = cache.get(key)
    if cached is not None:
        value, ts = cached
        if definitive(value) or (time.monotonic() - ts) < _PROBE_TTL_S:
            return value
    try:
        value = probe(agent.model, agent.base_url, getattr(agent, "api_key", ""))
    except Exception:
        value = unknown
    cache[key] = (value, time.monotonic())
    return value


def unset_reasoning_default(agent) -> dict | None:
    """Reasoning config for a main-loop request whose ``agent.reasoning_effort`` is unset.

    Asks the active provider profile (``ProviderProfile.default_reasoning_config``; the custom /
    OpenAI-compatible profile answers medium) so a route's own default never silently applies —
    kimi-k3 behind a relay defaults to ``max``, 3x the reasoning tokens of medium. Resolved at
    request time, so ``/model`` and fallback activation re-evaluate it. None keeps the field off
    the wire: a non chat-completions transport, a profile without a default (those decide inside
    ``build_api_kwargs_extras``), a model the catalog / ``model_overrides`` mark
    ``supports_reasoning: false``, or a local Ollama model whose ``/api/show`` lacks ``thinking``.
    """
    if getattr(agent, "api_mode", None) != "chat_completions":
        return None
    provider = str(getattr(agent, "provider", "") or "")
    model = str(getattr(agent, "model", "") or "")
    try:
        from providers import get_provider_profile

        profile = get_provider_profile(provider)
        default = profile.default_reasoning_config(model) if profile is not None else None
    except Exception:
        return None
    if not default:
        return None
    try:
        from agent.models_dev import get_model_capabilities

        caps = get_model_capabilities(provider, model, allow_network=False)
    except Exception:
        caps = None
    if caps is not None and caps.supports_reasoning is False:
        return None
    # ``_ollama_num_ctx`` is only ever set for a server detected as Ollama (agent_init); Ollama
    # 400s ``reasoning_effort`` on a model pulled without the thinking capability.
    if getattr(agent, "_ollama_num_ctx", None) and not agent._ollama_supports_thinking_cached():
        return None
    return dict(default)


class ReasoningParamsMixin:
    """Reasoning-parameter gating and echo policy (see module docstring)."""

    def _supports_reasoning_extra_body(self) -> bool:
        """True when reasoning extra_body is safe to send: OpenRouter forwards unknown extra_body upstream and
        some routes 400 on ``reasoning``, so gate to known reasoning-capable families and direct Nous Portal."""
        url = self._base_url_lower
        if base_url_host_matches(url, "nousresearch.com") or base_url_host_matches(url, "ai-gateway.vercel.sh"):
            return True
        if (profile := self._reasoning_endpoint_profile()) is not None:
            # A claimed endpoint gates on its own catalog: reasoning goes out iff it declares a payload.
            from agent.provider_route_hooks import ask_profile
            return ask_profile(profile, "reasoning_payload", None, self.model, None,
                               base_url=self.base_url, scope=self) is not None
        if (self.provider or "").strip().lower() == "lmstudio":
            # "off-only" (or absent) means no real reasoning capability.
            return any(opt and opt != "off" for opt in self._lmstudio_reasoning_options_cached())
        if base_url_host_matches(url, "ollama.com"):
            # Ollama Cloud: /api/show capabilities are authoritative.
            return self._ollama_supports_thinking_cached()
        if not self._is_openrouter_url() or base_url_host_matches(url, "api.mistral.ai"):
            return False
        # Live-catalog metadata first (OpenRouter /v1/models supported_parameters) — the static prefix
        # allowlist repeatedly went stale one vendor at a time. Unknown falls back to the static list.
        try:
            from hermes_cli.models_reasoning_caps import openrouter_model_reasoning_capabilities, warm_openrouter_reasoning_caps_async
            caps = openrouter_model_reasoning_capabilities(self.model)
            if caps is None:
                warm_openrouter_reasoning_caps_async()  # cache cold — warm in the background, never block
        except Exception:
            caps = None
        if caps is not None:
            return bool(caps.get("supports_reasoning"))
        model = (self.model or "").lower()
        return any(model.startswith(prefix) for prefix in _OPENROUTER_REASONING_PREFIXES)

    def _lmstudio_reasoning_options_cached(self) -> list[str]:
        """LM Studio's published reasoning ``allowed_options`` (gate + clamp so toggle models don't 400 on ``high``)."""
        try:
            from hermes_cli.models_local import lmstudio_model_reasoning_options
        except Exception:
            return []
        return _cached_probe(self, "_lm_reasoning_opts_cache", lmstudio_model_reasoning_options, [], bool)

    def _ollama_supports_thinking_cached(self) -> bool:
        """True only if Ollama's ``/api/show`` declares the ``thinking`` capability."""
        try:
            from hermes_cli.models_local import ollama_model_supports_thinking
        except Exception:
            return False
        return bool(_cached_probe(self, "_ollama_thinking_cache", ollama_model_supports_thinking, None, lambda v: v is not None))

    def _reasoning_endpoint_profile(self):
        """The profile claiming this endpoint (``providers.profile_for_host``) that gates its reasoning, or None.
        Endpoints core gates itself (Nous Portal, Vercel AI Gateway, LM Studio, Ollama Cloud, OpenRouter) keep
        core's gate even when a plugin claims their host for metadata or auxiliary routing."""
        url = self._base_url_lower
        if ((self.provider or "").strip().lower() == "lmstudio" or self._is_openrouter_url()
                or any(base_url_host_matches(url, host) for host in _CORE_REASONING_GATED_HOSTS)):
            return None
        from providers import profile_for_host

        return profile_for_host(str(getattr(self, "base_url", None) or ""))

    def _endpoint_reasoning_payload(self) -> dict | None:
        """``reasoning_payload`` of the profile gating this endpoint's reasoning for the agent's model and
        ``reasoning_config`` (``_reasoning_endpoint_profile``), or None when no profile does."""
        base_url = getattr(self, "base_url", None)
        profile = self._reasoning_endpoint_profile()
        if profile is None:
            return None
        from agent.provider_route_hooks import ask_profile
        return ask_profile(profile, "reasoning_payload", None, self.model, self.reasoning_config,
                           base_url=str(base_url), scope=self)

    def _build_assistant_message(self, assistant_message, finish_reason: str) -> dict:
        """``build_assistant_message``; a held turn's row with visible text comes back typed hidden
        (``withhold_held_row``) until ``finish_text_response`` publishes it as the final. The row is
        stamped with the response's reasoning count: the replay price of its (encrypted) reasoning."""
        from agent.chat_completion_helpers import build_assistant_message
        from agent.message_metadata import stamp_reasoning_tokens
        from agent.stream_delivery import withhold_held_row

        msg = build_assistant_message(self, assistant_message, finish_reason)
        stamp_reasoning_tokens(msg, getattr(self, "_last_response_reasoning_tokens", 0))
        return withhold_held_row(self, msg)

    def _reasoning_replay_route(self):
        """Reasoning replay decision for the active route (``message_sanitization.reasoning_replay_route``).

        Cached per (api_mode, provider, model, base_url, opt-in, rejected keys) — called many times
        per turn — and recomputed after ``switch_model()`` / fallback activation or a recorded
        field rejection, the only events allowed to change the replayed bytes mid-session.
        """
        from agent.message_sanitization import reasoning_replay_route, rejected_reasoning_carriers

        rejected = rejected_reasoning_carriers(self)
        key = (getattr(self, "api_mode", None), self.provider, self.model, getattr(self, "_base_url_lower", self.base_url),
               self._reasoning_echo_opt_in(), rejected)
        cached = getattr(self, "_reasoning_route_cache", None)
        if cached is not None and cached[0] == key:
            return cached[1]
        route = reasoning_replay_route(key[0], self.provider, self.model, self.base_url,
                                       echo_opt_in=key[4], rejected=rejected)
        self._reasoning_route_cache = (key, route)
        return route

    def _needs_thinking_reasoning_pad(self) -> bool:
        """True for the must-echo tier: DeepSeek / Kimi / MiMo thinking 400 on a replayed tool-call turn
        without a non-empty ``reasoning_content`` (#15250, #17400), plus a ``model.reasoning_echo`` opt-in
        for gateways proxying them. Never true on a route that does not read the field."""
        return self._reasoning_replay_route().pad

    def _reasoning_echo_opt_in(self) -> bool:
        """``model.reasoning_echo``: treat the *current* provider as must-echo (pad tool-call turns) — for
        gateways proxying DeepSeek/Kimi/MiMo that the host rules miss. Replay itself is on by default;
        fallback activation swaps the flag and ``restore_primary_runtime()`` restores it."""
        return bool(getattr(self, "_reasoning_echo_flag", False))

    @staticmethod
    def _read_reasoning_echo_from_config() -> bool:
        """Read ``model.reasoning_echo`` from config; False on any error."""
        try:
            from hermes_cli.config import load_config_readonly
            return bool((load_config_readonly().get("model") or {}).get("reasoning_echo"))
        except Exception as exc:  # health: allow BLE001 -- a config failure must fall back, not fail init
            # Log the class, never the config value or exception traceback.
            logging.getLogger("run_agent").warning(
                "Agent configuration for model.reasoning_echo could not be loaded (%s); "
                "using the default reasoning echo setting. Check the active Hermes Python "
                "environment and dependencies; run 'hermes config check' after "
                "configuration imports work again.",
                type(exc).__name__,
            )
            return False

    # Echo families are host/provider-driven, not model-name-driven: aggregators re-exporting Kimi reject the
    # echo. Rule table: ``message_sanitization._REASONING_ECHO_RULES``. Kimi deliberately passes the raw
    # provider and no model (its rule matches exact provider ids + hosts only).
    def _needs_kimi_tool_reasoning(self) -> bool:
        """True when the current provider is Kimi / Moonshot thinking mode."""
        return matches_reasoning_echo_family("kimi", self.provider, None, self.base_url)

    def _needs_deepseek_tool_reasoning(self) -> bool:
        """True when the current provider is DeepSeek thinking mode (omitting the echo is an HTTP 400).

        DeepSeek V4 thinking mode requires ``reasoning_content`` on every assistant tool-call turn; omitting
        it causes HTTP 400 when the message is replayed in a subsequent API request (#15250).
        """
        return matches_reasoning_echo_family("deepseek", (self.provider or "").lower(), self.model, self.base_url)

    def _needs_mimo_tool_reasoning(self) -> bool:
        """True when the current provider is Xiaomi MiMo thinking mode."""
        return matches_reasoning_echo_family("mimo", (self.provider or "").lower(), self.model, self.base_url)

    _copy_reasoning_content_for_api = _forward("agent.agent_runtime_helpers", "copy_reasoning_content_for_api")

    _reapply_reasoning_echo_for_provider = _forward("agent.agent_runtime_helpers", "reapply_reasoning_echo_for_provider")

    @staticmethod
    def _sanitize_tool_calls_for_strict_api(api_msg: dict, model: str | None = None, *, base_url: str | None = None,
                                            provider: str | None = None) -> dict:
        """Strip Codex Responses fields from tool_calls for strict Chat Completions APIs (Mistral, Fireworks
        400/422 on unknown fields). ``extra_content`` (Gemini thought_signature) is kept only on Gemini routes
        (model family, Gemini host or provider). Builds new dicts so the internal history keeps the Codex
        fields for a later fallback."""
        tool_calls = api_msg.get("tool_calls")
        if not isinstance(tool_calls, list):
            return api_msg
        from agent.transports.chat_completions import _model_consumes_thought_signature
        keep_signature = _model_consumes_thought_signature(model, base_url, provider)
        strip = {"call_id", "response_item_id"} | (set() if keep_signature else {"extra_content"})
        api_msg["tool_calls"] = [{k: v for k, v in tc.items() if k not in strip} if isinstance(tc, dict) else tc
                                 for tc in tool_calls]
        return api_msg

    _sanitize_tool_call_arguments = _forward_static("agent.agent_runtime_helpers", "sanitize_tool_call_arguments")

    def _should_sanitize_tool_calls(self) -> bool:
        """True for every non-Codex API: Codex Responses fields are not Chat Completions schema and 400 elsewhere."""
        return self.api_mode != "codex_responses"