"""
Pydantic models for Demand Response Service
"""

from datetime import datetime
from typing import List, Dict, Optional, Literal
from pydantic import BaseModel, Field
from enum import Enum


# Enums
class InvitationStatus(str, Enum):
    """Invitation status states"""
    PENDING = "pending"
    SCHEDULED = "scheduled"
    ACTIVE = "active"
    COMPLETED = "completed"
    CANCELLED = "cancelled"


class ResponseType(str, Enum):
    """Device response types"""
    WAITING = "WAITING"
    YES = "YES"
    NO = "NO"


class EventStatus(str, Enum):
    """DR event status states"""
    SCHEDULED = "scheduled"
    ACTIVE = "active"
    COMPLETED = "completed"
    CANCELLED = "cancelled"


class InstructionType(str, Enum):
    """Device participation instruction types"""
    PARTICIPATION = "participation"  # Full DR participation (100%)
    SHIFTING = "shifting"  # Partial participation (0-20%)
    OFF = "off"  # No DR participation


# Invitation Models
class EventRequest(BaseModel):
    """Request model for creating a DR event (alias for DRInvitationCreate)"""
    event_time: datetime = Field(..., description="When the DR event should occur")
    load_kwh: float = Field(..., description="Target load reduction in kWh", gt=0)
    load_percentage: float = Field(..., description="Target reduction as percentage of total load", ge=0, le=100)
    iots: List[str] = Field(..., description="List of device IDs to participate", min_items=1)
    duration_minutes: int = Field(59, description="Event duration in minutes", gt=0, le=120)

    class Config:
        json_schema_extra = {
            "example": {
                "event_time": "2025-12-10T14:00:00",
                "load_kwh": 5.0,
                "load_percentage": 15.0,
                "iots": ["sensor_1", "sensor_2"],
                "duration_minutes": 59
            }
        }


class DRInvitationCreate(BaseModel):
    """Request model for creating a DR invitation"""
    event_time: datetime = Field(..., description="When the DR event should occur")
    load_kwh: float = Field(..., description="Target load reduction in kWh", gt=0)
    load_percentage: float = Field(..., description="Target reduction as percentage of total load", ge=0, le=100)
    iots: List[str] = Field(..., description="List of device IDs to participate", min_items=1)
    duration_minutes: int = Field(59, description="Event duration in minutes", gt=0, le=120)

    class Config:
        json_schema_extra = {
            "example": {
                "event_time": "2025-12-10T14:00:00",
                "load_kwh": 5.0,
                "load_percentage": 15.0,
                "iots": ["sensor_1", "sensor_2"],
                "duration_minutes": 59
            }
        }


class DRInvitationResponse(BaseModel):
    """Response model for device answering invitation"""
    event_id: str = Field(..., description="Event identifier")
    iot_id: str = Field(..., description="Device identifier")
    response: ResponseType = Field(..., description="Device response (YES/NO)")
    committed_reduction_kw: Optional[float] = Field(None, description="Committed power reduction in kW", ge=0)

    class Config:
        json_schema_extra = {
            "example": {
                "event_id": "550e8400-e29b-41d4-a716-446655440000",
                "iot_id": "sensor_1",
                "response": "YES",
                "committed_reduction_kw": 2.5
            }
        }


class DRInvitation(BaseModel):
    """Full DR invitation model"""
    event_id: str = Field(..., description="Unique event identifier")
    created_at: datetime = Field(..., description="Invitation creation time")
    event_time: datetime = Field(..., description="Scheduled event start time")
    load_kwh: float = Field(..., description="Target load reduction in kWh")
    load_percentage: float = Field(..., description="Target reduction percentage")
    iots: List[str] = Field(..., description="Participating device IDs")
    duration_minutes: int = Field(..., description="Event duration in minutes")
    response: str = Field(..., description="Overall response status")
    status: str = Field(..., description="Invitation status")

    class Config:
        json_encoders = {
            datetime: lambda v: v.isoformat() if v else None
        }
        json_schema_extra = {
            "example": {
                "event_id": "550e8400-e29b-41d4-a716-446655440000",
                "created_at": "2025-12-10T13:45:00",
                "event_time": "2025-12-10T14:00:00",
                "load_kwh": 5.0,
                "load_percentage": 15.0,
                "iots": ["sensor_1", "sensor_2"],
                "duration_minutes": 59,
                "response": "WAITING",
                "status": "pending"
            }
        }


# Event Models
class EventScheduleRequest(BaseModel):
    """Request model for scheduling a DR event"""
    event_time: datetime = Field(..., description="Event start time")
    iots: List[str] = Field(..., description="Participating device IDs", min_items=1)
    load_reduction_kw: float = Field(..., description="Target reduction in kW", gt=0)
    duration_minutes: int = Field(59, description="Event duration in minutes", gt=0, le=120)

    class Config:
        json_schema_extra = {
            "example": {
                "event_time": "2025-12-10T14:00:00",
                "iots": ["sensor_1", "sensor_2"],
                "load_reduction_kw": 5.0,
                "duration_minutes": 59
            }
        }


class PowerSample(BaseModel):
    """Individual power sample during event"""
    timestamp: datetime = Field(..., description="Sample timestamp")
    device_powers: Dict[str, float] = Field(..., description="Device power readings (device_id -> kW)")
    interval_reduction_kwh: Optional[float] = Field(None, description="Reduction for this interval")


class DREvent(BaseModel):
    """DR event execution model"""
    event_id: str = Field(..., description="Unique event identifier")
    invitation_id: Optional[str] = Field(None, description="Source invitation ID if applicable")
    start_time: datetime = Field(..., description="Event start time")
    end_time: datetime = Field(..., description="Event end time")
    status: EventStatus = Field(..., description="Event status")
    participating_devices: List[str] = Field(..., description="Device IDs participating")
    target_reduction_kw: float = Field(..., description="Target power reduction in kW")
    actual_reduction_kw: float = Field(0.0, description="Actual achieved reduction in kWh")
    power_samples: List[Dict] = Field(default_factory=list, description="Power samples during event")

    class Config:
        json_encoders = {
            datetime: lambda v: v.isoformat() if v else None
        }


class ActiveEventResponse(BaseModel):
    """Response model for active event with real-time data"""
    event_id: str = Field(..., description="Event identifier")
    status: EventStatus = Field(..., description="Current status")
    start_time: datetime = Field(..., description="Event start time")
    end_time: datetime = Field(..., description="Event end time")
    participating_devices: List[str] = Field(..., description="Participating devices")
    target_reduction_kw: float = Field(..., description="Target reduction")
    actual_reduction_kw: float = Field(..., description="Current achieved reduction")
    current_device_powers: Optional[Dict[str, float]] = Field(None, description="Current device power readings")
    progress_percentage: Optional[float] = Field(None, description="Event progress (0-100%)")

    class Config:
        json_encoders = {
            datetime: lambda v: v.isoformat() if v else None
        }


class LoadReductionRequest(BaseModel):
    """Request model for executing load reduction"""
    event_time: datetime = Field(..., description="Event start time")
    iot: str = Field(..., description="Device ID")

    class Config:
        json_schema_extra = {
            "example": {
                "event_time": "2025-12-10T14:00:00",
                "iot": "sensor_1"
            }
        }


# Flexibility Models
class DeviceFlexibility(BaseModel):
    """Per-device flexibility information"""
    device_id: str = Field(..., description="Device identifier")
    available_kw: float = Field(..., description="Available flexibility in kW", ge=0)
    instruction: str = Field(..., description="Current DR instruction")
    current_power: float = Field(..., description="Current power consumption in kW", ge=0)


class FlexibilityResponse(BaseModel):
    """Response model for current flexibility"""
    timestamp: datetime = Field(..., description="Calculation timestamp")
    total_flexibility_kw: float = Field(..., description="Total available flexibility in kW", ge=0)
    devices: List[DeviceFlexibility] = Field(..., description="Per-device breakdown")

    class Config:
        json_encoders = {
            datetime: lambda v: v.isoformat() if v else None
        }
        json_schema_extra = {
            "example": {
                "timestamp": "2025-12-10T13:45:00",
                "total_flexibility_kw": 15.5,
                "devices": [
                    {
                        "device_id": "sensor_1",
                        "available_kw": 3.5,
                        "instruction": "participation",
                        "current_power": 3.5
                    },
                    {
                        "device_id": "sensor_2",
                        "available_kw": 0.8,
                        "instruction": "shifting",
                        "current_power": 4.0
                    }
                ]
            }
        }


class DeviceInstructionUpdate(BaseModel):
    """Model for updating device instructions"""
    device_id: str = Field(..., description="Device identifier")
    instructions: Dict[str, str] = Field(..., description="Hourly instructions (hour -> instruction type)")

    class Config:
        json_schema_extra = {
            "example": {
                "device_id": "sensor_1",
                "instructions": {
                    "0": "participation",
                    "1": "shifting",
                    "2": "off",
                    "3": "participation"
                }
            }
        }


# Configuration Models
class AutoResponseConfig(BaseModel):
    """Auto-response configuration model"""
    enabled: bool = Field(..., description="Whether auto-response is enabled")
    max_reduction_percentage: float = Field(20.0, description="Maximum reduction percentage for auto-accept", ge=0, le=100)
    response_delay_seconds: int = Field(300, description="Delay before auto-responding (seconds)", ge=0)
    min_notice_minutes: int = Field(60, description="Minimum notice required for auto-accept (minutes)", ge=0)

    class Config:
        json_schema_extra = {
            "example": {
                "enabled": True,
                "max_reduction_percentage": 20.0,
                "response_delay_seconds": 300,
                "min_notice_minutes": 60
            }
        }


# Response Models
class InvitationSendResponse(BaseModel):
    """Response for sending invitation"""
    event_id: str = Field(..., description="Created event identifier")
    response: str = Field(..., description="Initial response status")
    message: str = Field(..., description="Status message")


class InvitationAnswerResponse(BaseModel):
    """Response for answering invitation"""
    success: bool = Field(..., description="Whether answer was recorded")
    message: str = Field(..., description="Status message")


class EventScheduleResponse(BaseModel):
    """Response for scheduling event"""
    event_id: str = Field(..., description="Scheduled event identifier")
    message: str = Field(..., description="Status message")


class PerformanceAnalytics(BaseModel):
    """Performance analytics response"""
    period_days: int = Field(..., description="Analysis period in days")
    total_events: int = Field(..., description="Total number of events")
    total_reduction_kwh: float = Field(..., description="Total energy reduced")
    total_target_kwh: float = Field(..., description="Total target reduction")
    average_reduction_kwh: float = Field(..., description="Average reduction per event")
    achievement_rate: float = Field(..., description="Achievement rate (%)")
    average_event_duration_minutes: int = Field(..., description="Average event duration")


# Health Check Model
class HealthResponse(BaseModel):
    """Health check response model"""
    service: str = Field(..., description="Service name")
    status: str = Field(..., description="Service status")
    timestamp: datetime = Field(..., description="Check timestamp")
    version: str = Field(..., description="Service version")

    class Config:
        json_encoders = {
            datetime: lambda v: v.isoformat() if v else None
        }
        json_schema_extra = {
            "example": {
                "service": "demand-response-service",
                "status": "healthy",
                "timestamp": "2025-12-10T13:45:00",
                "version": "1.0.0"
            }
        }