from typing import List
from fastapi import APIRouter, Depends, HTTPException, BackgroundTasks
from sqlalchemy.orm import Session, joinedload
from .. import models, schemas, proxmox_client as pve
from ..config import settings
from ..database import get_db
from ..deps import get_current_user

router = APIRouter(prefix="/instances", tags=["instances"])


@router.get("", response_model=List[schemas.InstanceOut])
def list_my_instances(db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    query = db.query(models.Instance).options(joinedload(models.Instance.template))
    query = query.filter(models.Instance.status != models.InstanceStatus.deleted)
    if user.role != models.Role.admin:
        query = query.filter(models.Instance.owner_id == user.id)
    return query.order_by(models.Instance.created_at.desc()).all()


def _provision(instance_id: int, template_id: int, node: str):
    """Фоновое создание VPS через Proxmox API."""
    from ..database import SessionLocal
    db = SessionLocal()
    try:
        instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
        if not instance:
            return
        template = db.query(models.Template).filter(models.Template.id == template_id).first()
        if not template:
            instance.status = models.InstanceStatus.error
            instance.root_password = "ERROR: шаблон не найден"
            db.commit()
            return
        try:
            if template.guest_type == models.GuestType.vm:
                clean_name = ''.join(c for c in instance.name.strip() if c.isalnum() or c == '-').lower() or 'vm'
                pve.clone_vm(template.source_vmid, instance.vmid, clean_name, node)
                pve.resize_vm(instance.vmid, template.cores, template.memory_mb, node)
                pve.resize_disk(instance.vmid, template.disk_gb, node)
                if instance.ciuser and instance.root_password:
                    pve.configure_cloud_init(instance.vmid, instance.ciuser, instance.root_password, node)
                pve.guest_action("vm", instance.vmid, "start", node)
            else:
                clean_name = ''.join(c for c in instance.name.strip() if c.isalnum() or c == '-').lower() or 'lxc'
                password = pve.create_lxc(
                    new_vmid=instance.vmid, name=clean_name,
                    template_volid=template.source_template,
                    cores=template.cores, memory_mb=template.memory_mb,
                    disk_gb=template.disk_gb, node=node,
                )
                instance.root_password = password
                pve.guest_action("lxc", instance.vmid, "start", node)
            instance.status = models.InstanceStatus.running
        except Exception as exc:
            instance.status = models.InstanceStatus.error
            instance.root_password = f"ERROR: {exc}"
        db.commit()
    finally:
        db.close()


@router.post("", response_model=schemas.InstanceOut)
def create_instance(
    payload: schemas.InstanceCreate,
    background_tasks: BackgroundTasks,
    db: Session = Depends(get_db),
    user: models.User = Depends(get_current_user),
):
    template = db.query(models.Template).filter(
        models.Template.id == payload.template_id, models.Template.is_active == True
    ).first()
    if not template:
        raise HTTPException(status_code=404, detail="Шаблон не найден")

    for _ in range(100):
        try:
            vmid = pve.get_next_vmid()
        except Exception as exc:
            raise HTTPException(status_code=502, detail=f"Proxmox недоступен: {exc}")
        exists = db.query(models.Instance).filter(
            models.Instance.vmid == vmid,
            models.Instance.status != models.InstanceStatus.deleted,
        ).first()
        if not exists:
            break
    else:
        raise HTTPException(status_code=409, detail="Не удалось найти свободный VMID")

    clean_name = ''.join(c for c in payload.name.strip() if c.isalnum() or c == '-').lower() or 'vps'

    # Proxmox переиспользует освободившиеся vmid — вычищаем мёртвые записи,
    # иначе INSERT упадёт с duplicate key по ix_instances_vmid
    stale = db.query(models.Instance).filter(
        models.Instance.vmid == vmid,
        models.Instance.status.in_([
            models.InstanceStatus.error,
            models.InstanceStatus.deleted,
            models.InstanceStatus.deleting,
        ]),
    ).all()
    for s in stale:
        db.delete(s)
    if stale:
        db.commit()
    instance = models.Instance(
        name=clean_name, vmid=vmid, node=settings.pve_node,
        guest_type=template.guest_type, status=models.InstanceStatus.creating,
        owner_id=user.id, template_id=template.id,
        ciuser=payload.ciuser or None,
        root_password=payload.cipassword or None,
    )
    db.add(instance)
    db.commit()
    db.refresh(instance)
    background_tasks.add_task(_provision, instance.id, template.id, settings.pve_node)
    return instance


@router.get("/{instance_id}", response_model=schemas.InstanceOut)
def get_instance(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    return instance


@router.get("/{instance_id}/status")
def get_instance_status(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    try:
        return pve.get_status(instance.guest_type.value, instance.vmid, instance.node)
    except Exception as exc:
        raise HTTPException(status_code=502, detail=f"Proxmox недоступен: {exc}")


@router.get("/{instance_id}/ip")
def get_instance_ip(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    try:
        ip = pve.get_instance_ip(instance.vmid, instance.node)
        return {"ip": ip}
    except Exception as exc:
        return {"ip": f"ошибка: {exc}"}


@router.post("/{instance_id}/action")
def instance_action(instance_id: int, payload: schemas.InstanceAction, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    try:
        pve.guest_action(instance.guest_type.value, instance.vmid, payload.action, instance.node)
    except Exception as exc:
        raise HTTPException(status_code=502, detail=f"Ошибка: {exc}")
    if payload.action == "start":
        instance.status = models.InstanceStatus.running
    elif payload.action in ("stop", "shutdown"):
        instance.status = models.InstanceStatus.stopped
    db.commit()
    return {"ok": True}


@router.get("/{instance_id}/ip")
def get_instance_ip(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    """Возвращает IP-адрес инстанса."""
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    if user.role != models.Role.admin and instance.owner_id != user.id:
        raise HTTPException(status_code=403, detail="Нет доступа")
    try:
        ip = pve.get_instance_ip(instance.vmid, instance.node)
        return {"ip": ip}
    except Exception as exc:
        return {"ip": f"ошибка: {exc}"}

@router.get("/{instance_id}/ip")
def get_instance_ip(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    """Возвращает IP-адрес инстанса."""
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    if user.role != models.Role.admin and instance.owner_id != user.id:
        raise HTTPException(status_code=403, detail="Нет доступа")
    try:
        ip = pve.get_instance_ip(instance.vmid, instance.node)
        return {"ip": ip}
    except Exception as exc:
        return {"ip": f"ошибка: {exc}"}

@router.get("/{instance_id}/live")
def get_instance_live(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    """Live CPU/RAM/Memory показатели."""
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    try:
        return pve.get_live_stats(instance.vmid, instance.node)
    except Exception as exc:
        return {"cpu": 0, "mem_used": 0, "mem_total": 0, "uptime": 0, "status": "error", "error": str(exc)}

@router.delete("/{instance_id}")
def delete_instance(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    try:
        pve.delete_guest(instance.guest_type.value, instance.vmid, instance.node)
    except Exception as exc:
        raise HTTPException(status_code=502, detail=f"Ошибка удаления: {exc}")
    instance.status = models.InstanceStatus.deleted
    db.commit()
    return {"ok": True}


@router.get("/{instance_id}/console")
def instance_console(instance_id: int, db: Session = Depends(get_db), user: models.User = Depends(get_current_user)):
    instance = db.query(models.Instance).filter(models.Instance.id == instance_id).first()
    if not instance:
        raise HTTPException(status_code=404, detail="VPS не найден")
    try:
        ticket = pve.get_vnc_ticket(instance.guest_type.value, instance.vmid, instance.node)
    except Exception as exc:
        raise HTTPException(status_code=502, detail=f"Консоль недоступна: {exc}")
    ticket["instance_id"] = instance.id
    return ticket