package logic

import (
	"context"

	"spark-server/internal/module/deliver/entity"
	inboxlogic "spark-server/internal/module/inbox/logic"
	syncentity "spark-server/internal/module/sync/entity"
	"spark-server/internal/transport/tcp/protocol"
	"spark-server/internal/transport/tcp/session"
)

type Mailbox interface {
	Put(ctx context.Context, userID int64, eventType syncentity.EventType, conversationID int64, payload []byte) error
}

// InboxFanout updates Redis dialog ZSET then pushes to online sessions.
func InboxFanout(sessions session.Manager, inbox inboxlogic.Store, mailbox Mailbox) Handler {
	push := SessionFanout(sessions)
	return func(ctx context.Context, job *entity.Job) error {
		if err := applyInbox(ctx, inbox, job); err != nil {
			return err
		}
		if err := applyMailbox(ctx, mailbox, job); err != nil {
			return err
		}
		return push(ctx, job)
	}
}

func applyInbox(ctx context.Context, inbox inboxlogic.Store, job *entity.Job) error {
	if inbox == nil || job == nil || job.ConversationID == 0 {
		return nil
	}
	if len(job.Preview) > 0 {
		if err := inbox.SetPreview(ctx, job.ConversationID, job.Preview); err != nil {
			return err
		}
	}
	if job.Cmd != 0 && job.Cmd != protocol.CmdMessage {
		return nil
	}
	score := job.MsgID
	for _, uid := range job.ToUserIDs {
		if uid == job.FromUserID {
			if err := inbox.TouchRead(ctx, uid, job.ConversationID, score); err != nil {
				return err
			}
			continue
		}
		if err := inbox.TouchUnread(ctx, uid, job.ConversationID, score); err != nil {
			return err
		}
		if err := inbox.IncrUnread(ctx, uid, job.ConversationID, 1); err != nil {
			return err
		}
	}
	return nil
}

func applyMailbox(ctx context.Context, mailbox Mailbox, job *entity.Job) error {
	if mailbox == nil || job == nil || job.NotMailbox {
		return nil
	}
	ev := mailboxEventType(job.Cmd)
	if ev == 0 {
		return nil
	}
	for _, uid := range job.ToUserIDs {
		if err := mailbox.Put(ctx, uid, ev, job.ConversationID, job.Payload); err != nil {
			return err
		}
	}
	return nil
}

func mailboxEventType(cmd uint16) syncentity.EventType {
	switch cmd {
	case protocol.CmdRecallMessage:
		return syncentity.EventRecall
	case protocol.CmdDeleteMessage:
		return syncentity.EventDelete
	default:
		return 0
	}
}