package protocol

import (
    "time"
)

type PacketType int

const (
    ReqPK PacketType = iota
    ReqAllMsg
    ReqMsg
    SubmitMsg
    SendPK
    Msg
)

type PacketBody interface{}

type Packet struct {
    Flag PacketType
    Body PacketBody
}

// Client --> Server: Ask for a user's public key
type RequestPubKey struct {
    FromUID string
    KeyUID  string
}

func NewRequestPubKey(fromUID, keyUID string) Packet {
    return Packet{
        Flag: ReqPK,
        Body: RequestPubKey{
            FromUID: fromUID,
            KeyUID:  keyUID,
        },
    }
}

// Client --> Server: Ask for all the client's messages in the queue
type RequestAllMsg struct {
    FromUID string
}

func NewRequestAllMsg(fromUID string) Packet {
    return Packet{
        Flag: ReqAllMsg,
        Body: RequestAllMsg{
            FromUID: fromUID,
        },
    }
}

// Client --> Server: Ask for a specific message in the queue
type RequestMsg struct {
    Num uint16
}

func NewRequestMsg(num uint16) Packet {
    return Packet{
        Flag: ReqMsg,
        Body: RequestMsg{
            Num: num,
        },
    }
}

// Client --> Server: Send message from client to server
type SubmitMessage struct {
    ToUID   string
    Subject []byte
    Body    []byte
}

func NewSubmitMessage(toUID string, subject, body []byte) Packet {
    return Packet{
        Flag: SubmitMsg,
        Body: SubmitMessage{
            ToUID:   toUID,
            Subject: subject,
            Body:    body,
        },
    }
}

// Server --> Client: Send the client the requested public key
type SendPubKey struct {
    Key []byte
}

func NewSendPubKey(key []byte) Packet {
    return Packet{
        Flag: SendPK,
        Body: SendPubKey{
            Key: key,
        },
    }
}

// Server --> Client: Send the client a message
type Message struct {
    FromUID   string
    ToUID     string
    Subject   []byte
    Body      []byte
    Timestamp time.Time
}

func NewMessage(fromUID, toUID string, subject, body []byte, timestamp time.Time) Packet {
    return Packet{
        Flag: Msg,
        Body: Message{
            FromUID:   fromUID,
            ToUID:     toUID,
            Subject:   subject,
            Body:      body,
            Timestamp: timestamp,
        },
    }
}