"""
backend/api/agent_checkpoint.py — Simplified checkpoint endpoints (ARCH-K2.3)

Aggiunge alias /api/agent/checkpoint (senza task_id nella path) per uso diretto dal frontend:
  GET    /api/agent/checkpoint             — lista tutti i checkpoint attivi in memoria
  POST   /api/agent/checkpoint             — salva checkpoint (taskId opzionale nel body)
  GET    /api/agent/checkpoint/{task_id}   — recupera checkpoint specifico
  DELETE /api/agent/checkpoint/{task_id}   — elimina checkpoint

I checkpoint per-task esistono già su /api/agent/tasks/{id}/checkpoint (agent.py).
Questi alias sono più comodi quando il frontend non ha un task_id esplicito
(es. salvataggio periodico dello stato dell'agente, resume dopo refresh).

ROUTING CF PAGES: /api/agent/* → HANDS (Space B) via HANDS_PATTERNS[0].
Nessuna modifica a [[catchall]].ts necessaria.

NOTA: Import da api.agent e api.persistence sono LAZY (dentro le funzioni)
per evitare import circolari — agent.py importa già molti altri moduli.
"""
import time
import asyncio
import logging
from typing import Optional

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel

from .auth_guard import require_role, AuthRole

_logger = logging.getLogger("api.agent_checkpoint")

router = APIRouter(dependencies=[Depends(require_role(AuthRole.MACHINE))])


class CheckpointBody(BaseModel):
    taskId:     Optional[str]  = None   # se omesso → usa "default"
    step:       int            = 0
    goal:       str            = ""
    plan:       list           = []
    logs:       list[str]      = []
    artifacts:  list[str]      = []
    retryCount: int            = 0
    extra:      dict           = {}


# ── GET /api/agent/checkpoint ─────────────────────────────────────────────────
@router.get("/api/agent/checkpoint")
async def list_checkpoints_alias():
    """
    Lista tutti i checkpoint attivi in memoria.
    Alias leggero per /api/agent/checkpoints (agent.py).
    """
    # Import lazy — evita circolarità
    from api.agent import _task_checkpoints, _prune_checkpoints  # type: ignore[import]

    _prune_checkpoints()
    now = int(time.time() * 1000)
    return {
        "count": len(_task_checkpoints),
        "checkpoints": [
            {
                "taskId": k,
                "step":   v.get("step", 0),
                "goal":   v.get("goal", "")[:300],
                "age_ms": now - v.get("savedAt", now),
            }
            for k, v in _task_checkpoints.items()
        ],
    }


# ── POST /api/agent/checkpoint ────────────────────────────────────────────────
@router.post("/api/agent/checkpoint")
async def save_checkpoint_alias(body: CheckpointBody):
    """
    Salva un checkpoint. taskId opzionale: se omesso usa 'default'.
    Replica la logica di /api/agent/tasks/{id}/checkpoint con Supabase persist.
    """
    from api.agent import _task_checkpoints, _prune_checkpoints  # type: ignore[import]
    from api.persistence import sb_save_checkpoint               # type: ignore[import]

    _prune_checkpoints()
    task_id = body.taskId or "default"

    cp: dict = {
        "taskId":     task_id,
        "step":       body.step,
        "goal":       body.goal,
        "plan":       body.plan,
        "logs":       body.logs[-50:],   # mantieni solo gli ultimi 50 log
        "artifacts":  body.artifacts,
        "retryCount": body.retryCount,
        "extra":      body.extra,
        "savedAt":    int(time.time() * 1000),
    }
    _task_checkpoints[task_id] = cp
    # Persist su Supabase — fire-and-forget (stesso pattern di agent.py)
    asyncio.create_task(sb_save_checkpoint(task_id, body.step, cp))
    return {"saved": True, "taskId": task_id, "step": body.step}


# ── GET /api/agent/checkpoint/{task_id} ──────────────────────────────────────
@router.get("/api/agent/checkpoint/{task_id}")
async def get_checkpoint_alias(task_id: str):
    """
    Recupera il checkpoint per un task specifico.
    Cerca prima in memoria (_task_checkpoints), poi su Supabase via sb_get_checkpoint.
    """
    from api.agent import _task_checkpoints, _prune_checkpoints  # type: ignore[import]
    from api.persistence import sb_get_checkpoint                # type: ignore[import]

    _prune_checkpoints()
    cp = _task_checkpoints.get(task_id)
    if not cp:
        cp = await sb_get_checkpoint(task_id)
    if not cp:
        raise HTTPException(
            status_code=404,
            detail={"error": "checkpoint_not_found", "taskId": task_id},
        )
    return cp


# ── DELETE /api/agent/checkpoint/{task_id} ───────────────────────────────────
@router.delete("/api/agent/checkpoint/{task_id}")
async def delete_checkpoint_alias(task_id: str):
    """Rimuove il checkpoint da memoria in-process (non elimina da Supabase)."""
    from api.agent import _task_checkpoints  # type: ignore[import]

    _task_checkpoints.pop(task_id, None)
    return {"deleted": task_id}