"""Settings management endpoints."""
from typing import Annotated

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session

from app.core.deps import get_current_admin, get_db
from app.models.settings import Settings
from app.models.user import User
from app.schemas.settings import SettingsResponse, SettingsUpdate
from app.services.audit_service import log_action

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


@router.get("", response_model=SettingsResponse)
def get_settings(
    db: Annotated[Session, Depends(get_db)],
    _: Annotated[User, Depends(get_current_admin)],
) -> Settings:
    """
    Get global settings (admin only).

    Returns the current global booking rules.
    """
    settings = db.query(Settings).filter(Settings.id == 1).first()
    if not settings:
        # Create default settings if not exist
        settings = Settings(
            id=1,
            min_duration_minutes=30,
            max_duration_minutes=480,
            working_hours_start=8,
            working_hours_end=20,
            max_bookings_per_day_per_user=3,
            min_hours_before_cancel=2,
        )
        db.add(settings)
        db.commit()
        db.refresh(settings)

    return settings


@router.put("", response_model=SettingsResponse)
def update_settings(
    settings_data: SettingsUpdate,
    db: Annotated[Session, Depends(get_db)],
    current_admin: Annotated[User, Depends(get_current_admin)],
) -> Settings:
    """
    Update global settings (admin only).

    All booking rules are validated on the client side and applied
    to all new booking requests.
    """
    settings = db.query(Settings).filter(Settings.id == 1).first()
    if not settings:
        # Create if not exist
        settings = Settings(id=1)
        db.add(settings)

    # Validate: min_duration <= max_duration
    if settings_data.min_duration_minutes > settings_data.max_duration_minutes:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Minimum duration cannot be greater than maximum duration",
        )

    # Validate: working_hours_start < working_hours_end
    if settings_data.working_hours_start >= settings_data.working_hours_end:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Working hours start must be before working hours end",
        )

    # Track which fields changed
    changed_fields = {}
    if settings.min_duration_minutes != settings_data.min_duration_minutes:
        changed_fields["min_duration_minutes"] = {
            "old": settings.min_duration_minutes,
            "new": settings_data.min_duration_minutes
        }
    if settings.max_duration_minutes != settings_data.max_duration_minutes:
        changed_fields["max_duration_minutes"] = {
            "old": settings.max_duration_minutes,
            "new": settings_data.max_duration_minutes
        }
    if settings.working_hours_start != settings_data.working_hours_start:
        changed_fields["working_hours_start"] = {
            "old": settings.working_hours_start,
            "new": settings_data.working_hours_start
        }
    if settings.working_hours_end != settings_data.working_hours_end:
        changed_fields["working_hours_end"] = {
            "old": settings.working_hours_end,
            "new": settings_data.working_hours_end
        }
    if settings.max_bookings_per_day_per_user != settings_data.max_bookings_per_day_per_user:
        changed_fields["max_bookings_per_day_per_user"] = {
            "old": settings.max_bookings_per_day_per_user,
            "new": settings_data.max_bookings_per_day_per_user
        }
    if settings.min_hours_before_cancel != settings_data.min_hours_before_cancel:
        changed_fields["min_hours_before_cancel"] = {
            "old": settings.min_hours_before_cancel,
            "new": settings_data.min_hours_before_cancel
        }

    # Update all fields
    setattr(settings, "min_duration_minutes", settings_data.min_duration_minutes)
    setattr(settings, "max_duration_minutes", settings_data.max_duration_minutes)
    setattr(settings, "working_hours_start", settings_data.working_hours_start)
    setattr(settings, "working_hours_end", settings_data.working_hours_end)
    setattr(settings, "max_bookings_per_day_per_user", settings_data.max_bookings_per_day_per_user)
    setattr(settings, "min_hours_before_cancel", settings_data.min_hours_before_cancel)

    db.commit()
    db.refresh(settings)

    # Log the action
    log_action(
        db=db,
        action="settings_updated",
        user_id=current_admin.id,
        target_type="settings",
        target_id=1,  # Settings ID is always 1 (singleton)
        details={"changed_fields": changed_fields}
    )

    return settings