from datetime import datetime
from app.models.session import TaskHistory, Task
from app.services.storage import storage
from app.core.logging import logger

HISTORY_KEY = "task_history"


class HistoryService:
    def __init__(self):
        self._history: list[dict] = []

    def load(self):
        data = storage.load(HISTORY_KEY, [])
        self._history = data if isinstance(data, list) else []
        logger.info(f"Loaded {len(self._history)} history records")

    def save(self):
        storage.save(HISTORY_KEY, self._history)

    def add_task_history(self, task: Task):
        history = TaskHistory(
            id=task.id,
            type=task.type,
            prompt=task.prompt,
            status=task.status,
            session_id=task.session_id,
            schedule=task.schedule,
            created_at=task.created_at.isoformat()
            if task.created_at
            else datetime.now().isoformat(),
            started_at=task.started_at.isoformat() if task.started_at else None,
            finished_at=task.finished_at.isoformat() if task.finished_at else None,
            error=task.error,
        )
        self._history.append(history.model_dump())
        self.save()
        logger.info(f"Added task {task.id} to history")

    def get_history(self, limit: int | None = None) -> list[TaskHistory]:
        history = [TaskHistory(**h) for h in self._history]
        if limit:
            return history[-limit:]
        return history

    def clear_history(self):
        self._history = []
        self.save()
        logger.info("Cleared task history")


history_service = HistoryService()