"""Auto training: suggest and apply heuristic updates from reflection and failures."""

from typing import Any, Protocol

from fusionagi.schemas.recommendation import TrainingSuggestion, TrainingSuggestionKind
from fusionagi._logger import logger


class ReflectiveMemoryLike(Protocol):
    """Protocol for reflective memory: set_heuristic, get_lessons."""

    def set_heuristic(self, key: str, value: Any) -> None: ...
    def get_lessons(self, limit: int = 50) -> list[dict[str, Any]]: ...
    def get_all_heuristics(self) -> dict[str, Any]: ...


class AutoTrainer:
    """
    Suggests training actions (heuristic updates, prompt tuning, fine-tune datasets)
    from lessons and evaluations, and applies heuristic updates to reflective memory.
    """

    def __init__(self, reflective_memory: ReflectiveMemoryLike | None = None) -> None:
        """
        Initialize the auto-trainer.

        Args:
            reflective_memory: Optional reflective memory for applying heuristics.
        """
        self._memory = reflective_memory

    def suggest_from_evaluation(
        self,
        task_id: str,
        evaluation: dict[str, Any],
    ) -> list[TrainingSuggestion]:
        """
        From a single Critic evaluation, produce training suggestions
        (heuristic_update from suggestions, fine_tune_dataset on failure).
        """
        suggestions: list[TrainingSuggestion] = []
        ev_suggestions = evaluation.get("suggestions", [])
        success = evaluation.get("success", False)
        score = evaluation.get("score", 0.5)

        for i, s in enumerate(ev_suggestions[:5]):
            key = f"heuristic_from_task_{task_id}_{i}"
            suggestions.append(
                TrainingSuggestion(
                    kind=TrainingSuggestionKind.HEURISTIC_UPDATE,
                    key=key,
                    value=s,
                    source_task_id=task_id,
                    reason="From Critic evaluation suggestion",
                )
            )
        if not success or score < 0.5:
            suggestions.append(
                TrainingSuggestion(
                    kind=TrainingSuggestionKind.FINE_TUNE_DATASET,
                    key=f"training_target_{task_id}",
                    value={
                        "task_id": task_id,
                        "outcome": "failed" if not success else "low_score",
                        "score": score,
                        "suggestions": ev_suggestions,
                    },
                    source_task_id=task_id,
                    reason="Task failed or low score; add to training dataset",
                )
            )
        return suggestions

    def suggest_from_lessons(self, limit_lessons: int = 20) -> list[TrainingSuggestion]:
        """
        Aggregate lessons into training suggestions (e.g. strategy_param
        or heuristic updates from repeated patterns).
        """
        if not self._memory:
            return []
        lessons = self._memory.get_lessons(limit=limit_lessons)
        suggestions: list[TrainingSuggestion] = []
        for lesson in lessons[-10:]:
            ev = lesson.get("evaluation", {})
            tid = lesson.get("task_id", "unknown")
            for i, s in enumerate(ev.get("suggestions", [])[:2]):
                key = f"lesson_heuristic_{tid}_{i}"
                suggestions.append(
                    TrainingSuggestion(
                        kind=TrainingSuggestionKind.HEURISTIC_UPDATE,
                        key=key,
                        value=s,
                        source_task_id=tid,
                        reason="From reflective lesson",
                    )
                )
        return suggestions

    def suggest_training(
        self,
        task_id: str | None = None,
        evaluation: dict[str, Any] | None = None,
        include_lessons: bool = True,
    ) -> list[TrainingSuggestion]:
        """
        Produce all training suggestions from optional evaluation and
        optionally from lessons.
        """
        out: list[TrainingSuggestion] = []
        if task_id and evaluation:
            out.extend(self.suggest_from_evaluation(task_id, evaluation))
        if include_lessons:
            out.extend(self.suggest_from_lessons())
        logger.debug(
            "AutoTrainer.suggest_training",
            extra={"count": len(out), "task_id": task_id},
        )
        return out

    def apply_heuristic_updates(
        self,
        suggestions: list[TrainingSuggestion],
        reflective_memory: ReflectiveMemoryLike | None = None,
    ) -> int:
        """
        Apply heuristic-update suggestions to reflective memory.
        Returns number of heuristics applied. Other suggestion kinds are logged
        but not applied (e.g. fine_tune_dataset for external pipelines).
        """
        memory = reflective_memory or self._memory
        if not memory:
            logger.warning("AutoTrainer.apply_heuristic_updates: no reflective memory")
            return 0
        applied = 0
        for s in suggestions:
            if s.kind == TrainingSuggestionKind.HEURISTIC_UPDATE:
                memory.set_heuristic(s.key, s.value)
                applied += 1
                logger.info(
                    "AutoTrainer: applied heuristic",
                    extra={"key": s.key, "source_task_id": s.source_task_id},
                )
            else:
                logger.info(
                    "AutoTrainer: suggestion not applied (use external pipeline)",
                    extra={"kind": s.kind.value, "key": s.key},
                )
        return applied

    def run_auto_training(
        self,
        task_id: str | None = None,
        evaluation: dict[str, Any] | None = None,
        apply_heuristics: bool = True,
    ) -> list[TrainingSuggestion]:
        """
        Suggest training from evaluation/lessons and optionally apply
        heuristic updates. Returns all suggestions (for logging or external use).
        """
        suggestions = self.suggest_training(
            task_id=task_id,
            evaluation=evaluation,
            include_lessons=True,
        )
        if apply_heuristics:
            self.apply_heuristic_updates(suggestions)
        return suggestions