"""AI Generation router — start generation, poll status, check credits."""

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.database import get_db
from app.models import User
from app.schemas import GenerateRequest, GenerateStatusResponse
from app.middleware.auth import get_current_user

router = APIRouter()


@router.post("", response_model=GenerateStatusResponse)
async def start_generation(
    body: GenerateRequest,
    db: AsyncSession = Depends(get_db),
    user: User = Depends(get_current_user),
):
    """Start an AI shader generation job. (Track I — stub)"""
    # TODO: Implement in Track I
    # - Credits check / BYOK validation
    # - Enqueue ai_generate job
    # - Return job_id for polling
    raise HTTPException(
        status_code=status.HTTP_501_NOT_IMPLEMENTED,
        detail="AI generation coming in M5"
    )


@router.get("/status/{job_id}", response_model=GenerateStatusResponse)
async def get_generation_status(
    job_id: str,
    user: User = Depends(get_current_user),
):
    """Poll AI generation job status. (Track I — stub)"""
    raise HTTPException(
        status_code=status.HTTP_501_NOT_IMPLEMENTED,
        detail="AI generation coming in M5"
    )


@router.get("/credits")
async def get_credits(user: User = Depends(get_current_user)):
    """Check remaining AI generation credits."""
    return {
        "credits_remaining": user.ai_credits_remaining,
        "subscription_tier": user.subscription_tier,
    }