"""Strict-output inference runtime for OpenEnv validators."""

from __future__ import annotations

from typing import Any

from compat import install_openenv_fastmcp_compat

from app.agents.review_agent import ReviewAgent
from app.models.inference import AgentDecision, InferenceConfig
from app.services.openai_service import OpenAIActionPlanner
from app.utils.runtime import (
    compact_text,
    format_bool,
    format_error,
    format_reward,
    observation_attr,
    parse_task_ids,
    suppress_output,
)

install_openenv_fastmcp_compat()

try:
    from models import PythonCodeReviewAction
    from server.env import PythonCodeReviewEnvironment
except ImportError:  # pragma: no cover
    from python_env.models import PythonCodeReviewAction  # type: ignore[no-redef]
    from python_env.server.env import PythonCodeReviewEnvironment  # type: ignore[no-redef]


class InferenceRunner:
    """Run benchmark tasks with strict single-line progress output."""

    def __init__(self, config: InferenceConfig) -> None:
        self.config = config
        self.agent = ReviewAgent(OpenAIActionPlanner(config))

    def run(self) -> int:
        for task_name in parse_task_ids():
            self.run_task(task_name)
        return 0

    def run_task(self, task_name: str) -> None:
        rewards: list[str] = []
        step_count = 0
        success = False
        fatal_error: str | None = None
        final_score = 0.0

        self._emit_start(task_name)

        try:
            env = self._create_env()
            observation = self._reset_env(env, task_name)
            done = bool(observation_attr(observation, "done", False))
            final_score = float(observation_attr(observation, "score", 0.0) or 0.0)
            max_steps = max(
                1,
                min(
                    self.config.max_episode_steps,
                    int(observation_attr(observation, "attempts_remaining", self.config.max_episode_steps) or self.config.max_episode_steps),
                ),
            )
            while not done and step_count < max_steps:
                decision = self.agent.act(observation)
                observation, reward, done, info = self._step_env(env, decision)
                step_count += 1
                final_score = float(observation_attr(observation, "score", final_score) or final_score)
                rewards.append(format_reward(reward))
                step_error = self._resolve_step_error(info, observation, decision)
                self._emit_step(step_count, decision.action_type, reward, done, step_error)

            if not done and step_count >= max_steps:
                fatal_error = "step budget exhausted"
            success = bool(done) and fatal_error is None and final_score >= self.config.success_threshold
        except Exception as exc:
            fatal_error = compact_text(f"{type(exc).__name__}: {exc}", default="runtime failure")
        finally:
            self._emit_end(success=success, step_count=step_count, rewards=rewards)

    def _create_env(self) -> PythonCodeReviewEnvironment:
        with suppress_output():
            return PythonCodeReviewEnvironment(verbose=False)

    def _reset_env(self, env: PythonCodeReviewEnvironment, task_name: str) -> Any:
        with suppress_output():
            return env.reset(task_id=task_name)

    def _step_env(
        self,
        env: PythonCodeReviewEnvironment,
        decision: AgentDecision,
    ) -> tuple[Any, float, bool, dict[str, Any]]:
        action = PythonCodeReviewAction(action_type=decision.action_type, code=decision.code)
        with suppress_output():
            observation, reward, done, info = env.step_result(action)
        return observation, float(reward), bool(done), dict(info or {})

    def _resolve_step_error(
        self,
        info: dict[str, Any],
        observation: Any,
        decision: AgentDecision,
    ) -> str | None:
        env_error = compact_text(
            info.get("last_action_error") or observation_attr(observation, "last_action_error", None),
            default="",
        )
        if env_error:
            return env_error
        if decision.error:
            return compact_text(decision.error, default="")
        return None

    def _emit_start(self, task_name: str) -> None:
        print(
            f"[START] task={task_name} env={self.config.benchmark_name} model={self.config.model_name}",
            flush=True,
        )

    def _emit_step(self, step_count: int, action: str, reward: float, done: bool, error: str | None) -> None:
        print(
            f"[STEP]  step={step_count} action={compact_text(action, default='analyze_code')} "
            f"reward={format_reward(reward)} done={format_bool(done)} error={format_error(error)}",
            flush=True,
        )

    def _emit_end(self, *, success: bool, step_count: int, rewards: list[str]) -> None:
        print(
            f"[END]   success={format_bool(success)} steps={step_count} rewards={','.join(rewards)}",
            flush=True,
        )


def main() -> int:
    """Entrypoint used by the root-level inference wrapper."""

    return InferenceRunner(InferenceConfig.from_env()).run()