package rpc

import (
	"regexp"
	"strings"
)

// DeviceUIDLength is the length of device UID's
const DeviceUIDLength = 32

// DeviceUIDInvalid is the defacto invalid UID from the RPC specification
const DeviceUIDInvalid = "00000000000000000000000000000000"

// VersionMap is a map of versions
type VersionMap map[VersionKey]string

// DeviceInfo is the device:info result devices
type DeviceInfo struct {
	Type    DeviceType `json:"type" msgpack:"type"`       // Type is the device type
	Version VersionMap `json:"version" msgpack:"version"` // Version is the Sem-ver firmware or hardware version
}

// DeviceData is the device:data result for devices
type DeviceData struct {
	State  DeviceState `json:"state" msgpack:"state"`                       // State is the device state
	Error  bool        `json:"error" msgpack:"error"`                       // Error is whether there is an error
	Errors []ErrorCode `json:"errors,omitempty" msgpack:"errors,omitempty"` // Errors is the list of errors
}

// DeviceType is a type which represent device types
type DeviceType string

// nolint: golint
const (
	DeviceTypeCRM3000     DeviceType = "crm-3000"
	DeviceTypeCRTMGateway DeviceType = "crtm-gateway"
	DeviceTypeCRTMSensor  DeviceType = "crtm-sensor"
	DeviceTypeDNCM        DeviceType = "dncm"
	DeviceTypeTWS3000DUM  DeviceType = "tws-3000-dum"
	DeviceTypeTWS3000DUU  DeviceType = "tws-3000-duu"
	DeviceTypeGRB3000     DeviceType = "greenhub-3000"
	DeviceTypeTWS3000WUM  DeviceType = "tws-3000-wum"
	DeviceTypeZKL3000     DeviceType = "zkl-3000"
	DeviceTypeZKL3000RC   DeviceType = "zkl-3000-rc"
	DeviceTypeZKL3000RCC  DeviceType = "zkl-3000-rcc"
	DeviceTypeReedSensor  DeviceType = "reed-sensor"
	DeviceTypeService     DeviceType = "service"
)

// VersionKey is a version key
type VersionKey string

// nolint: golint
const (
	VersionKeyFwService           VersionKey = "fw-service"
	VersionKeyFwCRM               VersionKey = "fw-crm"
	VersionKeyHwCRM               VersionKey = "hw-crm"
	VersionKeyFwGateway           VersionKey = "fw-gateway"
	VersionKeyHwGateway           VersionKey = "hw-gateway"
	VersionKeyFwCRTM              VersionKey = "fw-crtm"
	VersionKeyHwCRTM              VersionKey = "hw-crtm"
	VersionKeyFwDNCM              VersionKey = "fw-dncm"
	VersionKeyHwDNCM              VersionKey = "hw-dncm"
	VersionKeyFwGRB               VersionKey = "fw-grb"
	VersionKeyHwGRB               VersionKey = "hw-grb"
	VersionKeyFwDUM               VersionKey = "fw-dum"
	VersionKeyHwDUM               VersionKey = "hw-dum"
	VersionKeyFwDUU               VersionKey = "fw-duu"
	VersionKeyHwDUU               VersionKey = "hw-duu"
	VersionKeyFwWUMMain           VersionKey = "fw-main"
	VersionKeyHwWUMMain           VersionKey = "hw-main"
	VersionKeyFwWUMMonitor        VersionKey = "fw-monitor"
	VersionKeyHwWUMMonitor        VersionKey = "hw-monitor"
	VersionKeyFwZKLMain           VersionKey = "fw-main"
	VersionKeyHwZKLMain           VersionKey = "hw-main"
	VersionKeyFwZKLWcpu           VersionKey = "fw-wcpu"
	VersionKeyFwZKLRCMain         VersionKey = "fw-main"
	VersionKeyHwZKLRCMain         VersionKey = "hw-main"
	VersionKeyFwZKLRCWcpu         VersionKey = "fw-wcpu"
	VersionKeyFwZKLRCSwitchConrol VersionKey = "fw-switch_control"
	VersionKeyFwZKLRCSwitchMeas   VersionKey = "fw-switch_meas"
	VersionKeyFwZKLRCSwitchDrive  VersionKey = "fw-switch_drive"
	VersionKeyHwZKLRCSwitch       VersionKey = "hw-switch"
)

// nolint: gochecknoglobals
var reVersionKey = regexp.MustCompile(`^hw-[a-z_]|^fw-[a-z_]`)

// IsValid checks if the key matches the required pattern
func (v VersionKey) IsValid() bool {
	return reVersionKey.MatchString(string(v))
}

// DeviceState is a state which a devices resides in
type DeviceState string

// nolint: golint
const (
	DeviceStateService DeviceState = "service"
	DeviceStateIdle    DeviceState = "idle"
	DeviceStateArmed   DeviceState = "armed"
	DeviceStateActive  DeviceState = "active"
)

// Device UID prefixes from the RPC specification
// nolint: golint
const (
	DeviceUIDPrefixRegular       string = "00"
	DeviceUIDPrefixLegacy        string = "01"
	DeviceUIDPrefixSimulator     string = "02"
	DeviceUIDPrefixXBee          string = "03"
	DeviceUIDPrefixNBIoT         string = "04"
	DeviceUIDPrefixLoRa          string = "05"
	DeviceUIDPrefixService       string = "fe"
	DeviceUIDPrefixServiceNBIoT  string = DeviceUIDPrefixService + "00"
	DeviceUIDPrefixServiceLoRa   string = DeviceUIDPrefixService + "01"
	DeviceUIDPrefixServiceCP3000 string = DeviceUIDPrefixService + "02"
	DeviceUIDPrefixMock          string = "ff"
)

// GenerateDeviceUID uses a 2 character prefix and a suffix and concatenates them
// to a single Device UID, it returns an error when the suffix is too long or
// when the prefix is invalid. It also makes sure the resulting UID is lowercase.
func GenerateDeviceUID(prefix, suffix string) (string, error) {
	length := len(prefix) + len(suffix)
	if length > DeviceUIDLength {
		return DeviceUIDInvalid, ErrDeviceUIDTooLong
	}
	return strings.ToLower(prefix + strings.Repeat("0", DeviceUIDLength-length) + suffix), nil
}

// IsValid checks:
//  - Type may not be empty
//  - Version must contain at least one element
//  - All version keys are valid
func (d *DeviceInfo) IsValid() bool {
	if string(d.Type) == "" {
		return false
	}

	if len(d.Version) == 0 {
		return false
	}

	for component := range d.Version {
		if !component.IsValid() {
			return false
		}
	}

	return true
}