package entity

import "fmt"

// Kind selects private_message vs group_message. Same numbers as conversation.Type; not a SQL column.
type Kind int

const (
	KindPrivate Kind = 1
	KindGroup   Kind = 2
)

func (k Kind) Valid() bool {
	return k == KindPrivate || k == KindGroup
}

// Message is a persisted IM body. Content is serialized JSON bytes, not a string.
type Message struct {
	ID             int64
	ConversationID int64
	SenderID       int64
	ReceiverID     int64 // private_message only; 0 for system
	GroupID        int64 // group_message only; groups.id 群号
	ClientMsgID    string
	Type           Type
	Kind           Kind
	Content        []byte
	Status         Status
	CreatedAtMS    int64
}

func (m *Message) Payload() (*Content, error) {
	if m == nil {
		return nil, nil
	}
	c, err := UnmarshalContent(m.Content)
	if err != nil {
		return nil, err
	}
	if c.Type != m.Type {
		return nil, fmt.Errorf("content: column type %d != payload %d", m.Type, c.Type)
	}
	return c, nil
}