package mqtt

import (
	"fmt"
	"log"

	"git.k7n.net/mats/go-telldus/pkg/datastore"
	"git.k7n.net/mats/go-telldus/pkg/telldus"
)

// DeviceDiscovery represents Home Assistant device discovery payload
type DeviceDiscovery struct {
	Name         string                 `json:"name"`
	CommandTopic string                 `json:"command_topic"`
	StateTopic   string                 `json:"state_topic"`
	UniqueID     string                 `json:"unique_id"`
	Device       map[string]interface{} `json:"device"`
}

// SensorDiscovery represents Home Assistant sensor discovery payload
type SensorDiscovery struct {
	Name              string                 `json:"name"`
	StateTopic        string                 `json:"state_topic"`
	UnitOfMeasurement string                 `json:"unit_of_measurement,omitempty"`
	DeviceClass       string                 `json:"device_class,omitempty"`
	UniqueID          string                 `json:"unique_id"`
	Device            map[string]interface{} `json:"device"`
}

// PublishAllDiscovery publishes Home Assistant discovery messages for all devices and sensors
func (c *Client) PublishAllDiscovery() error {
	if err := c.publishDeviceDiscovery(); err != nil {
		return err
	}
	if err := c.publishSensorDiscovery(); err != nil {
		return err
	}
	return nil
}

// publishDeviceDiscovery publishes discovery for all devices
func (c *Client) publishDeviceDiscovery() error {
	for device := range c.store.ListDevices() {
		if err := c.PublishDeviceDiscovery(device.ID); err != nil {
			log.Printf("Error publishing discovery for device %d: %v", device.ID, err)
		}
	}
	return nil
}

// PublishDeviceDiscovery publishes Home Assistant discovery for a single device
func (c *Client) PublishDeviceDiscovery(deviceID int) error {
	device, err := c.store.GetDevice(deviceID)
	if err != nil {
		return fmt.Errorf("device %d not found: %w", deviceID, err)
	}

	topic := fmt.Sprintf("homeassistant/switch/%s/config", device.UniqueID)
	payload := fmt.Sprintf(`{
		"name": "%s",
		"command_topic": "telldus/device/%d/set",
		"state_topic": "telldus/device/%d/state",
		"unique_id": "%s",
		"device": {
			"identifiers": ["telldus_%d"],
			"name": "%s",
			"manufacturer": "Telldus"
		}
	}`, device.Name, deviceID, deviceID, device.UniqueID, deviceID, device.Name)

	c.client.Publish(topic, 0, true, payload)
	return nil
}

// publishSensorDiscovery publishes discovery for all sensors
func (c *Client) publishSensorDiscovery() error {
	var protocol, model string
	var id, dataTypes int
	ret := telldus.Sensor(&protocol, &model, &id, &dataTypes)

	for ret == 0 {
		sensor, err := c.store.GetSensorByIdentity(protocol, model, id)
		if err != nil || sensor.Hidden {
			log.Printf("Sensor %s %s %d not in DB or hidden, skipping", protocol, model, id)
			ret = telldus.Sensor(&protocol, &model, &id, &dataTypes)
			continue
		}

		if err := c.publishSensorDiscoveryForSensor(sensor, dataTypes); err != nil {
			log.Printf("Error publishing discovery for sensor %s %s %d: %v", protocol, model, id, err)
		}

		ret = telldus.Sensor(&protocol, &model, &id, &dataTypes)
	}
	return nil
}

// PublishSensorDiscovery publishes Home Assistant discovery for a single sensor
func (c *Client) PublishSensorDiscovery(protocol, model string, id int) error {
	sensor, err := c.store.GetSensorByIdentity(protocol, model, id)
	if err != nil {
		return fmt.Errorf("sensor %s %s %d not found: %w", protocol, model, id, err)
	}

	// Get current data types from telldus
	var p, m string
	var sensorID, dataTypes int
	ret := telldus.Sensor(&p, &m, &sensorID, &dataTypes)

	// Find matching sensor
	for ret == 0 {
		if p == protocol && m == model && sensorID == id {
			return c.publishSensorDiscoveryForSensor(sensor, dataTypes)
		}
		ret = telldus.Sensor(&p, &m, &sensorID, &dataTypes)
	}

	return fmt.Errorf("sensor %s %s %d not found in telldus", protocol, model, id)
}

// publishSensorDiscoveryForSensor publishes discovery messages for a sensor's data types
func (c *Client) publishSensorDiscoveryForSensor(sensor *datastore.Sensor, dataTypes int) error {
	if dataTypes&telldus.DataTypeTemperature != 0 && sensor.TemperatureUniqueID != "" {
		topic := fmt.Sprintf("homeassistant/sensor/%s/config", sensor.TemperatureUniqueID)
		payload := fmt.Sprintf(`{
			"name": "%s Temperature",
			"state_topic": "telldus/sensor/%s/%s/%d/temperature",
			"unit_of_measurement": "°C",
			"device_class": "temperature",
			"unique_id": "%s",
			"device": {
				"identifiers": ["telldus_sensor_%s_%s_%d"],
				"name": "%s",
				"manufacturer": "Telldus"
			}
		}`, sensor.Name, sensor.Protocol, sensor.Model, sensor.ID, sensor.TemperatureUniqueID,
			sensor.Protocol, sensor.Model, sensor.ID, sensor.Name)
		c.client.Publish(topic, 0, true, payload)
	}

	if dataTypes&telldus.DataTypeHumidity != 0 && sensor.HumidityUniqueID != "" {
		topic := fmt.Sprintf("homeassistant/sensor/%s/config", sensor.HumidityUniqueID)
		payload := fmt.Sprintf(`{
			"name": "%s Humidity",
			"state_topic": "telldus/sensor/%s/%s/%d/humidity",
			"unit_of_measurement": "%%",
			"device_class": "humidity",
			"unique_id": "%s",
			"device": {
				"identifiers": ["telldus_sensor_%s_%s_%d"],
				"name": "%s",
				"manufacturer": "Telldus"
			}
		}`, sensor.Name, sensor.Protocol, sensor.Model, sensor.ID, sensor.HumidityUniqueID,
			sensor.Protocol, sensor.Model, sensor.ID, sensor.Name)
		c.client.Publish(topic, 0, true, payload)
	}

	return nil
}