package devices

import (
	"context"
	"fmt"

	"xiaomihome/xiaomi"
)

// TempHumiditySensor 温湿度传感器读取接口（只读）。
type TempHumiditySensor interface {
	Device

	GetTemperature(ctx context.Context) (float64, error)
	GetHumidity(ctx context.Context) (float64, error)
}

// NewTempHumiditySensor 创建温湿度传感器。失败返回错误（含无 SPEC / 无相关属性）。
func NewTempHumiditySensor(client *xiaomi.Client, info *xiaomi.DeviceInfo) (TempHumiditySensor, error) {
	if info == nil {
		return nil, xiaomi.ErrDeviceNotFound
	}

	miotDev := client.GetMIoTDevice(info.DID)
	if miotDev == nil {
		return nil, fmt.Errorf("%w: device not initialized", xiaomi.ErrDeviceNotFound)
	}
	spec := miotDev.SpecInstance()
	if spec == nil {
		return nil, fmt.Errorf("%w: device has no SPEC information", xiaomi.ErrNotSupported)
	}

	d := &tempHumidityDevice{
		BaseDevice: BaseDevice{client: client, info: info},
	}

	for _, svc := range spec.Services {
		for _, prop := range svc.Properties {
			switch propertyShortName(prop.Type) {
			case "temperature":
				if !d.propTemp.valid {
					d.propTemp = siidPiid{svc.IID, prop.PIID, true}
				}
			case "relative-humidity":
				if !d.propHumidity.valid {
					d.propHumidity = siidPiid{svc.IID, prop.PIID, true}
				}
			}
		}
	}

	if !d.propTemp.valid && !d.propHumidity.valid {
		return nil, fmt.Errorf("%w: no temperature or humidity property in SPEC", xiaomi.ErrNotSupported)
	}

	return d, nil
}

type tempHumidityDevice struct {
	BaseDevice
	propTemp     siidPiid
	propHumidity siidPiid
}

func (d *tempHumidityDevice) GetTemperature(ctx context.Context) (float64, error) {
	if !d.propTemp.valid {
		return 0, xiaomi.ErrNotSupported
	}
	prop, err := d.GetProp(ctx, d.propTemp.siid, d.propTemp.piid)
	if err != nil {
		return 0, err
	}
	return toFloat(prop.Value), nil
}

func (d *tempHumidityDevice) GetHumidity(ctx context.Context) (float64, error) {
	if !d.propHumidity.valid {
		return 0, xiaomi.ErrNotSupported
	}
	prop, err := d.GetProp(ctx, d.propHumidity.siid, d.propHumidity.piid)
	if err != nil {
		return 0, err
	}
	return toFloat(prop.Value), nil
}