package devices

import (
	"strings"

	"git.zeroonesoft.cn/golib/xiaomihome/xiaomi"
)

// Create creates the appropriate device control interface for the given device.
// It uses the device's URN (SPEC type) to determine which control interface to return.
//
// Returns:
//   - Switch, Light, AirConditioner, Fan, Cover, Humidifier, Vacuum,
//     WaterHeater, or Thermostat depending on the device type
//   - nil, nil if the device type is not recognized (no error, just unsupported)
//   - an error if there was a problem creating the control
//
// Usage:
//
//	info, _ := client.GetDevice(ctx, "some-did")
//	ctrl, err := devices.Create(client, info)
//	switch d := ctrl.(type) {
//	case devices.Switch:
//	    d.TurnOn(ctx)
//	case devices.Light:
//	    d.SetBrightness(ctx, 80)
//	}
func Create(client *xiaomi.Client, info *xiaomi.DeviceInfo) (interface{}, error) {
	return createImpl(client, info)
}

// NewDevice creates the appropriate device control interface, returning the
// common Device interface. Use type switch to access type-specific methods:
//
//	dev, err := devices.NewDevice(client, info)
//	switch d := dev.(type) {
//	case devices.Switch:
//	    d.TurnOn(ctx)
//	case devices.Light:
//	    d.SetBrightness(ctx, 80)
//	}
func NewDevice(client *xiaomi.Client, info *xiaomi.DeviceInfo) (Device, error) {
	ctrl, err := createImpl(client, info)
	if err != nil {
		return nil, err
	}
	if ctrl == nil {
		return nil, nil
	}
	return ctrl.(Device), nil
}

// createImpl is the internal implementation shared by Create and NewDevice.
func createImpl(client *xiaomi.Client, info *xiaomi.DeviceInfo) (interface{}, error) {
	if info == nil {
		return nil, xiaomi.ErrDeviceNotFound
	}

	urn := info.URN

	// Determine device type from URN and try constructors in order
	var ctrl interface{}
	var err error

	// URN-based routing
	// miot-spec-v2: air-conditioner → urn:miot-spec-v2:device:air-conditioner:...
	// miot-spec-v2: light → urn:miot-spec-v2:device:light:...
	// etc.
	switch {
	case matchURN(urn, "air-conditioner", "airer", "air-condition-outlet", "air-condition-eco", "ac-partner"):
		ctrl, err = NewAirConditioner(client, info)
	case matchURN(urn, "light", "lightbulb", "night-light", "ceiling-light"):
		ctrl, err = NewLight(client, info)
	case matchURN(urn, "switch", "powerstrip", "toggle-switch", "wireless-switch", "curtain-switch"):
		ctrl, err = NewSwitch(client, info)
	case matchURN(urn, "plug", "outlet"):
		ctrl, err = NewPlug(client, info)
	case matchURN(urn, "fan", "ceiling-fan", "ventilator", "air-fresh", "air-purifier"):
		ctrl, err = NewFan(client, info)
	case matchURN(urn, "curtain", "airer-rack", "airer"):
		ctrl, err = NewCover(client, info)
	case matchURN(urn, "humidifier", "dehumidifier", "humidifier-dehumidifier"):
		ctrl, err = NewHumidifier(client, info)
	case matchURN(urn, "vacuum", "sweeper", "robot-cleaner"):
		ctrl, err = NewVacuum(client, info)
	case matchURN(urn, "water-heater", "water-cooler", "kettle"):
		ctrl, err = NewWaterHeater(client, info)
	case matchURN(urn, "heater", "electric-blanket", "thermostat"):
		ctrl, err = NewAirConditioner(client, info)
	case matchURN(urn, "sensor-occupy", "sensor_occupy", "occupancy-sensor", "occupancy_sensor", "motion-sensor", "motion_sensor", "magnet"):
		ctrl, err = NewOccupancySensor(client, info)
	case matchURN(urn, "sensor-temp", "sensor_temp", "sensor-humidity", "sensor_humidity", "sensor-ht", "sensor_ht", "sensor-smoke", "sensor-gasm", "illumination"):
		ctrl, err = NewTempHumiditySensor(client, info)
	case matchURN(urn, "speaker", "bluetooth-speaker", "alarm-clock", "media-player", "playback", "music"):
		ctrl, err = NewSpeaker(client, info)
	case matchURN(urn, "gateway"):
		ctrl, err = NewGateway(client, info)
	default:
		// Not a supported device type — not an error, just returns nil
		return nil, nil
	}

	if err != nil {
		return nil, err
	}

	return ctrl, nil
}

// matchURN 匹配 URN 的 device 类型段。
// 标准格式 urn:miot-spec-v2:device:{TYPE}:... 做精确段匹配（避免 "tofan" 撞 "fan" 这类子串误判）；
// 非标准 URN 回退到边界子串匹配。
func matchURN(urn string, types ...string) bool {
	parts := strings.Split(urn, ":")
	if len(parts) >= 4 && parts[2] == "device" {
		devType := parts[3]
		for _, t := range types {
			if devType == t {
				return true
			}
		}
		return false
	}
	// 非标准 URN：按边界匹配，前后必须是分隔符，避免误撞
	for _, t := range types {
		if boundaryContains(urn, t) {
			return true
		}
	}
	return false
}

// boundaryContains 检查 sub 是否在 s 中出现且前后是分隔符或边界。
func boundaryContains(s, sub string) bool {
	for i := 0; i+len(sub) <= len(s); i++ {
		if s[i:i+len(sub)] != sub {
			continue
		}
		beforeOK := i == 0
		if !beforeOK {
			beforeOK = isBoundary(s[i-1])
		}
		afterOK := i+len(sub) == len(s)
		if !afterOK {
			afterOK = isBoundary(s[i+len(sub)])
		}
		if beforeOK && afterOK {
			return true
		}
	}
	return false
}

func isBoundary(c byte) bool {
	return c == ':' || c == '-' || c == '.' || c == '_' || c == '/'
}