"""Pydantic models for API validation."""

from datetime import datetime

from pydantic import BaseModel, Field, field_validator


class MqttConfig(BaseModel):
    """MQTT Broker configuration."""

    broker: str = Field("localhost", description="MQTT broker hostname")
    port: int = Field(1883, description="MQTT broker port")
    username: str = Field("", description="MQTT username (optional)")
    password: str = Field("", description="MQTT password (optional)")
    client_id: str = Field("iot_bridge", description="MQTT client ID")
    keepalive: int = Field(60, description="MQTT keepalive interval (s)")
    use_tls: bool = Field(False, description="Use TLS/SSL for MQTT connection")


class SessionConfig(BaseModel):
    """Session detection configuration for a device."""

    standby_threshold_w: float = Field(
        ..., gt=0, description="Power threshold for session start (W)"
    )
    working_threshold_w: float = Field(
        ..., gt=0, description="Power threshold for working state (W)"
    )
    start_debounce_s: float = Field(3.0, gt=0, description="Debounce time for session start (s)")
    stop_debounce_s: float = Field(15.0, gt=0, description="Debounce time for session stop (s)")
    message_timeout_s: float = Field(
        20.0, gt=0, description="Max time without messages before timeout (s)"
    )
    heartbeat_interval_s: float = Field(
        300.0, gt=0, description="Interval for heartbeat events (s)"
    )

    @field_validator("working_threshold_w")
    @classmethod
    def working_must_be_greater_than_standby(cls, v, info):
        """Validate that working threshold is greater than standby threshold."""
        standby = info.data.get("standby_threshold_w")
        if standby is not None and v <= standby:
            raise ValueError("working_threshold_w must be greater than standby_threshold_w")
        return v


class DeviceConfig(BaseModel):
    """Configuration for a single IoT device."""

    device_id: str = Field(..., min_length=1, description="Unique device identifier")
    machine_name: str = Field(..., min_length=1, description="Human-readable machine name")
    mqtt_topic: str = Field(..., min_length=1, description="MQTT topic to subscribe to")
    parser_type: str = Field("shelly_pm", description="Parser type (e.g., 'shelly_pm')")
    session_config: SessionConfig
    device_status_timeout_s: int = Field(
        120, ge=10, le=600, description="Device offline timeout in seconds (synced with message_timeout_s)"
    )


class BridgeConfig(BaseModel):
    """Complete bridge configuration from Odoo."""

    mqtt: MqttConfig | None = Field(None, description="MQTT broker configuration (optional)")
    devices: list[DeviceConfig] = Field(
        default_factory=list, description="List of devices to monitor"
    )
    timestamp: str | None = Field(
        default_factory=lambda: datetime.utcnow().isoformat(), description="Config timestamp"
    )
    version: str | None = Field("1.0", description="Config format version")

    @field_validator("devices")
    @classmethod
    def validate_unique_constraints(cls, v):
        """Validate that device_ids and mqtt_topics are unique."""
        # Check unique device IDs
        device_ids = [d.device_id for d in v]
        if len(device_ids) != len(set(device_ids)):
            raise ValueError("device_id must be unique")

        # Check unique MQTT topics
        topics = [d.mqtt_topic for d in v]
        if len(topics) != len(set(topics)):
            raise ValueError("mqtt_topic must be unique")

        return v