// Package realtime implements the WebSocket hub: real-time delivery of
// conversation events (messages, typing, presence, read receipts).
package realtime

import (
	"encoding/json"
	"time"
)

// Event type constants sent over the wire.
const (
	EventMessageCreated = "message.created"
	EventTyping         = "typing"
	EventPresence       = "presence"
	EventRead           = "read"
)

// Presence status values.
const (
	StatusOnline  = "online"
	StatusOffline = "offline"
)

// MessageCreated is published when a message is stored.
type MessageCreated struct {
	TempID         string    `json:"temp_id,omitempty"`
	ConversationID int64     `json:"conversation_id"`
	MessageID      int64     `json:"message_id"`
	SenderID       int64     `json:"sender_id"`
	Body           string    `json:"body"`
	CreatedAt      time.Time `json:"created_at"`
}

// Typing is published when a user starts or stops typing in a conversation.
type Typing struct {
	ConversationID int64 `json:"conversation_id"`
	UserID         int64 `json:"user_id"`
	IsTyping       bool  `json:"is_typing"`
}

// Presence is published when a user comes online or goes offline.
type Presence struct {
	UserID int64  `json:"user_id"`
	Status string `json:"status"`
}

// Read is published when a user marks messages in a conversation as read.
type Read struct {
	ConversationID int64 `json:"conversation_id"`
	UserID         int64 `json:"user_id"`
	MessageID      int64 `json:"message_id"`
}

// envelope is the wire format for every message, both inbound and outbound.
type envelope struct {
	Type string          `json:"type"`
	Data json.RawMessage `json:"data"`
}

// clientTyping is sent by the client to signal typing state.
type clientTyping struct {
	ConversationID int64 `json:"conversation_id"`
	IsTyping       bool  `json:"is_typing"`
}

// clientRead is sent by the client to mark messages as read.
type clientRead struct {
	ConversationID int64 `json:"conversation_id"`
	MessageID      int64 `json:"message_id"`
}