package protocol

// Message types
const (
	MsgRegister      = "register"
	MsgDeviceList    = "device_list"
	MsgRequestDevice = "request_device"
	MsgDeviceGranted = "device_granted"
	MsgDeviceDenied  = "device_denied"
	MsgReleaseDevice = "release_device"
	MsgDeviceReleased = "device_released"
	MsgClientJoined  = "client_joined"
	MsgClientLeft    = "client_left"
	MsgForceRelease  = "force_release"
	MsgPing          = "ping"
	MsgPong          = "pong"
	MsgError         = "error"
)

// Client modes
const (
	ModeShare = "share"
	ModeUse   = "use"
)

// Device status
const (
	StatusAvailable = "available"
	StatusInUse     = "in_use"
)

// Envelope is the top-level message wrapper
type Envelope struct {
	Type string `json:"type"`
}

// Register is sent by a client when connecting to the relay
type Register struct {
	Type     string `json:"type"`
	Hash     string `json:"hash"`
	Mode     string `json:"mode"`
	ClientID string `json:"client_id"`
	Name     string `json:"name"`
}

// USBDevice describes a USB device
type USBDevice struct {
	BusID     string `json:"bus_id"`
	BusNum    uint32 `json:"bus_num"`
	DevNum    uint32 `json:"dev_num"`
	Speed     uint32 `json:"speed"`
	VendorID  string `json:"vendor_id"`
	ProductID string `json:"product_id"`
	DeviceBCD string `json:"device_bcd,omitempty"`
	Class     uint8  `json:"class"`
	SubClass  uint8  `json:"sub_class"`
	Protocol  uint8  `json:"protocol"`
	Name      string `json:"name"`
	Manufacturer string `json:"manufacturer,omitempty"`
	NumInterfaces uint8 `json:"num_interfaces"`
	Status    string `json:"status"`
	UsedBy    string `json:"used_by,omitempty"`
}

// DeviceList is sent by share clients to announce available devices
type DeviceList struct {
	Type             string      `json:"type"`
	ClientID         string      `json:"client_id"`
	ClientName       string      `json:"client_name"`
	Devices          []USBDevice `json:"devices"`
	AllowForceDetach bool        `json:"allow_force_detach,omitempty"`
}

// RequestDevice is sent by use clients to request a specific device
type RequestDevice struct {
	Type         string `json:"type"`
	TargetClient string `json:"target_client"`
	BusID        string `json:"bus_id"`
	RequestID    string `json:"request_id"`
}

// DeviceGranted is sent by share clients when a device is ready
type DeviceGranted struct {
	Type      string `json:"type"`
	BusID     string `json:"bus_id"`
	TunnelID  string `json:"tunnel_id"`
	RequestID string `json:"request_id"`
	DevID     uint32 `json:"dev_id"` // (busnum << 16) | devnum
	Speed     uint32 `json:"speed"`
}

// DeviceDenied is sent when a device request is rejected
type DeviceDenied struct {
	Type      string `json:"type"`
	BusID     string `json:"bus_id"`
	RequestID string `json:"request_id"`
	Reason    string `json:"reason"`
}

// ReleaseDevice is sent by use clients to release a device
type ReleaseDevice struct {
	Type         string `json:"type"`
	TargetClient string `json:"target_client"`
	BusID        string `json:"bus_id"`
}

// DeviceReleased is sent when a device is released
type DeviceReleased struct {
	Type  string `json:"type"`
	BusID string `json:"bus_id"`
}

// ForceRelease is sent by use clients to force-release a device from another user
type ForceRelease struct {
	Type         string `json:"type"`
	TargetClient string `json:"target_client"`
	BusID        string `json:"bus_id"`
}

// ClientJoined is broadcast when a new client joins the group
type ClientJoined struct {
	Type     string `json:"type"`
	ClientID string `json:"client_id"`
	Mode     string `json:"mode"`
	Name     string `json:"name"`
}

// ClientLeft is broadcast when a client leaves the group
type ClientLeft struct {
	Type     string `json:"type"`
	ClientID string `json:"client_id"`
}

// Ping/Pong for keepalive
type Ping struct {
	Type string `json:"type"`
}

type Pong struct {
	Type string `json:"type"`
}

// Error message
type ErrorMsg struct {
	Type    string `json:"type"`
	Message string `json:"message"`
}

// TunnelHeader is prepended to binary WebSocket frames for tunnel data.
// Format: [16 bytes UUID][payload]
const TunnelHeaderSize = 16