"""Pydantic schemas for request/response validation.

All models are plain Pydantic BaseModel (not SQLModel) so they can be
used purely for API I/O without DB-session side-effects.
"""

from __future__ import annotations

from datetime import datetime
from typing import Any, Generic, List, Optional, TypeVar
from uuid import UUID

from pydantic import BaseModel, Field


# ──────────────────────────────────────────────────────────────────────
#  User
# ──────────────────────────────────────────────────────────────────────

class UserCreate(BaseModel):
    email: str
    password: str = Field(min_length=8)
    username: str = Field(min_length=3, max_length=50)
    first_name: str
    last_name: str
    phone: Optional[str] = None


class UserLogin(BaseModel):
    email: str
    password: str


class UserResponse(BaseModel):
    id: UUID
    email: str
    username: str
    first_name: str
    last_name: str
    phone: Optional[str] = None
    role: str
    avatar_url: Optional[str] = None
    is_active: bool
    created_at: datetime

    model_config = {"from_attributes": True}


# ──────────────────────────────────────────────────────────────────────
#  Auth / Token
# ──────────────────────────────────────────────────────────────────────

class TokenResponse(BaseModel):
    access_token: str
    refresh_token: str
    token_type: str = "bearer"


# ──────────────────────────────────────────────────────────────────────
#  Sensor
# ──────────────────────────────────────────────────────────────────────

class SensorResponse(BaseModel):
    id: UUID
    name: str
    type: str
    status: str
    latitude: float
    longitude: float
    zone_id: Optional[UUID] = None
    last_value: Optional[float] = None
    last_reading_at: Optional[datetime] = None
    battery_level: Optional[int] = None

    model_config = {"from_attributes": True}


class SensorReadingResponse(BaseModel):
    id: UUID
    sensor_id: UUID
    value: float
    unit: str
    quality: float
    recorded_at: datetime

    model_config = {"from_attributes": True}


# ──────────────────────────────────────────────────────────────────────
#  Zone
# ──────────────────────────────────────────────────────────────────────

class ZoneResponse(BaseModel):
    id: UUID
    name: str
    description: Optional[str] = None
    color: str
    geojson: Optional[str] = None

    model_config = {"from_attributes": True}


# ──────────────────────────────────────────────────────────────────────
#  Alert
# ──────────────────────────────────────────────────────────────────────

class AlertResponse(BaseModel):
    id: UUID
    sensor_id: UUID
    type: str
    severity: str
    message: str
    value: Optional[float] = None
    threshold: Optional[float] = None
    status: str
    created_at: datetime

    model_config = {"from_attributes": True}


# ──────────────────────────────────────────────────────────────────────
#  Dashboard
# ──────────────────────────────────────────────────────────────────────

class DashboardStats(BaseModel):
    total_sensors: int
    active_sensors: int
    total_readings_24h: int
    active_alerts: int
    avg_air_quality: Optional[float] = None
    avg_temperature: Optional[float] = None
    avg_humidity: Optional[float] = None


# ──────────────────────────────────────────────────────────────────────
#  Pagination (generic)
# ──────────────────────────────────────────────────────────────────────

T = TypeVar("T")


class PaginatedResponse(BaseModel, Generic[T]):
    items: List[T]
    total: int
    page: int
    page_size: int
    pages: int