from datetime import UTC, datetime

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

from app.api.deps import get_current_telegram_user, log_audit, require_platform_role
from app.core.config import settings
from app.db.session import get_session
from app.models.car import (
    AuditLog,
    ServiceCenter,
    ServiceCenterVerification,
    ServiceEmployee,
    ServiceVisit,
)
from app.models.user import User
from app.schemas.service_center import AdminModerationDecision, ServiceCenterRead, ServiceVisitRead

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


def require_admin_or_verifier(user: User) -> None:
    require_platform_role(user, {"admin", "verifier", "moderator"})


@router.get("/service-centers/pending", response_model=list[ServiceCenterRead])
async def pending_service_centers(
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> list[ServiceCenter]:
    require_admin_or_verifier(current_user)
    result = await session.execute(
        select(ServiceCenter)
        .where(ServiceCenter.verification_status == "pending")
        .order_by(ServiceCenter.created_at.asc())
    )
    return list(result.scalars())


@router.get("/service-centers/{service_center_id}", response_model=ServiceCenterRead)
async def admin_service_center_detail(
    service_center_id: int,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenter:
    require_admin_or_verifier(current_user)
    center = await session.get(ServiceCenter, service_center_id)
    if center is None:
        raise HTTPException(status_code=404, detail="Service center not found")
    return center


@router.post("/service-centers/{service_center_id}/verify", response_model=ServiceCenterRead)
async def verify_service_center(
    service_center_id: int,
    payload: AdminModerationDecision | None = None,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenter:
    require_admin_or_verifier(current_user)
    center = await session.get(ServiceCenter, service_center_id)
    if center is None:
        raise HTTPException(status_code=404, detail="Service center not found")
    center.verification_status = "approved"
    center.verified_at = datetime.now(UTC)
    if center.owner_user_id:
        owner = await session.get(User, center.owner_user_id)
        if owner:
            owner.platform_role = "service_owner"
            await ensure_owner_employee(session, center.id, owner.id)
            await notify_user(owner, f"Заявка СТО «{center.display_name or center.name}» одобрена. Панель СТО доступна в CarPass.")
    await mark_latest_verification(session, center.id, "approved", current_user.id, payload)
    await log_audit(
        session,
        actor=current_user,
        action="service_center.verify",
        target_type="service_center",
        target_id=center.id,
        metadata={"comment": payload.comment if payload else None},
    )
    await session.commit()
    await session.refresh(center)
    return center


@router.post("/service-centers/{service_center_id}/reject", response_model=ServiceCenterRead)
async def reject_service_center(
    service_center_id: int,
    payload: AdminModerationDecision | None = None,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenter:
    require_admin_or_verifier(current_user)
    center = await session.get(ServiceCenter, service_center_id)
    if center is None:
        raise HTTPException(status_code=404, detail="Service center not found")
    center.verification_status = "rejected"
    if center.owner_user_id:
        owner = await session.get(User, center.owner_user_id)
        if owner:
            reason = payload.reason or payload.comment if payload else None
            await notify_user(owner, f"Заявка СТО «{center.display_name or center.name}» отклонена.{f' Причина: {reason}' if reason else ''}")
    await mark_latest_verification(session, center.id, "rejected", current_user.id, payload)
    await log_audit(
        session,
        actor=current_user,
        action="service_center.reject",
        target_type="service_center",
        target_id=center.id,
        metadata={"reason": payload.reason if payload else None, "comment": payload.comment if payload else None},
    )
    await session.commit()
    await session.refresh(center)
    return center


@router.post("/service-centers/{service_center_id}/suspend", response_model=ServiceCenterRead)
async def suspend_service_center(
    service_center_id: int,
    payload: AdminModerationDecision | None = None,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenter:
    require_platform_role(current_user, {"admin"})
    center = await session.get(ServiceCenter, service_center_id)
    if center is None:
        raise HTTPException(status_code=404, detail="Service center not found")
    center.verification_status = "suspended"
    center.suspended_at = datetime.now(UTC)
    if center.owner_user_id:
        owner = await session.get(User, center.owner_user_id)
        if owner:
            reason = payload.reason or payload.comment if payload else None
            await notify_user(owner, f"СТО «{center.display_name or center.name}» временно заблокировано.{f' Причина: {reason}' if reason else ''}")
    await log_audit(
        session,
        actor=current_user,
        action="service_center.suspend",
        target_type="service_center",
        target_id=center.id,
        metadata={"reason": payload.reason if payload else None, "comment": payload.comment if payload else None},
    )
    await session.commit()
    await session.refresh(center)
    return center


@router.post("/service-centers/{service_center_id}/request-changes", response_model=ServiceCenterRead)
async def request_service_center_changes(
    service_center_id: int,
    payload: AdminModerationDecision,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenter:
    require_admin_or_verifier(current_user)
    center = await session.get(ServiceCenter, service_center_id)
    if center is None:
        raise HTTPException(status_code=404, detail="Service center not found")
    center.verification_status = "needs_changes"
    if center.owner_user_id:
        owner = await session.get(User, center.owner_user_id)
        if owner:
            reason = payload.reason or payload.comment or "Администратор попросил уточнить данные заявки."
            await notify_user(owner, f"По заявке СТО «{center.display_name or center.name}» нужны правки: {reason}")
    await mark_latest_verification(session, center.id, "needs_changes", current_user.id, payload)
    await log_audit(
        session,
        actor=current_user,
        action="service_center.request_changes",
        target_type="service_center",
        target_id=center.id,
        metadata={"reason": payload.reason, "comment": payload.comment},
    )
    await session.commit()
    await session.refresh(center)
    return center


@router.get("/audit-log")
async def audit_log(
    limit: int = 100,
    offset: int = 0,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> list[dict]:
    require_platform_role(current_user, {"admin", "verifier", "moderator"})
    limit = min(max(limit, 1), 200)
    result = await session.execute(
        select(AuditLog).order_by(AuditLog.created_at.desc()).limit(limit).offset(max(offset, 0))
    )
    return [
        {
            "id": item.id,
            "actor_user_id": item.actor_user_id,
            "actor_role": item.actor_role,
            "action": item.action,
            "target_type": item.target_type,
            "target_id": item.target_id,
            "metadata_json": item.metadata_json,
            "created_at": item.created_at,
        }
        for item in result.scalars()
    ]


@router.get("/disputes", response_model=list[ServiceVisitRead])
async def disputes(
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> list[ServiceVisit]:
    require_admin_or_verifier(current_user)
    result = await session.execute(
        select(ServiceVisit).where(ServiceVisit.status == "disputed").order_by(ServiceVisit.updated_at.desc())
    )
    return list(result.scalars())


async def mark_latest_verification(
    session: AsyncSession,
    service_center_id: int,
    status: str,
    reviewed_by: int,
    payload: AdminModerationDecision | None = None,
) -> None:
    result = await session.execute(
        select(ServiceCenterVerification)
        .where(ServiceCenterVerification.service_center_id == service_center_id)
        .order_by(ServiceCenterVerification.created_at.desc())
        .limit(1)
    )
    verification = result.scalar_one_or_none()
    if verification:
        verification.status = status
        verification.reviewed_by = reviewed_by
        verification.reviewed_at = datetime.now(UTC)
        if payload and (payload.reason or payload.comment):
            verification.comment = "\n".join(
                item for item in [payload.reason, payload.comment] if item
            )


async def ensure_owner_employee(session: AsyncSession, service_center_id: int, owner_user_id: int) -> None:
    result = await session.execute(
        select(ServiceEmployee).where(
            ServiceEmployee.service_center_id == service_center_id,
            ServiceEmployee.user_id == owner_user_id,
        )
    )
    employee = result.scalar_one_or_none()
    if employee is None:
        session.add(
            ServiceEmployee(
                service_center_id=service_center_id,
                user_id=owner_user_id,
                role="owner",
                status="active",
            )
        )
    else:
        employee.role = "owner"
        employee.status = "active"


async def notify_user(user: User, text: str) -> None:
    if not settings.bot_token:
        return
    try:
        async with httpx.AsyncClient(timeout=5) as client:
            await client.post(
                f"https://api.telegram.org/bot{settings.bot_token}/sendMessage",
                data={"chat_id": str(user.telegram_id), "text": text},
            )
    except Exception:
        return