package helpers

import (
	"errors"
	"os"
	"path/filepath"
	"time"

	"forge.redroom.link/yves/meowlib"
	"forge.redroom.link/yves/meowlib/client"
)

func PackMessageForServer(packedMsg *meowlib.PackedUserMessage, srvuid string) ([]byte, string, error) {
	// Get the message server
	srv, err := client.GetConfig().GetIdentity().MessageServers.LoadServer(srvuid)
	if err != nil {
		return nil, "messageBuildPostprocess : LoadServer", err
	}
	// Creating Server message for transporting the user message
	toServerMessage := srv.BuildToServerMessageFromUserMessage(packedMsg)
	data, err := srv.ProcessOutboundMessage(toServerMessage)
	if err != nil {
		return nil, "messageBuildPostprocess : ProcessOutboundMessage", err
	}
	return data, "", nil

}

func CreateStorePackUserMessageForServer(message string, srvuid string, peer_uid string, replyToUid string, filelist []string) ([]byte, string, error) {
	usermessage, errtxt, err := CreateAndStoreUserMessage(message, peer_uid, replyToUid, filelist)
	if err != nil {
		return nil, errtxt, err
	}
	return PackMessageForServer(usermessage, srvuid)
}

func CreateAndStoreUserMessage(message string, peer_uid string, replyToUid string, filelist []string) (*meowlib.PackedUserMessage, string, error) {
	peer := client.GetConfig().GetIdentity().Peers.GetFromUid(peer_uid)

	// Creating User message
	usermessage, err := peer.BuildSimpleUserMessage([]byte(message))
	if err != nil {
		return nil, "PrepareServerMessage : BuildSimpleUserMessage", err
	}
	for _, file := range filelist {
		err = usermessage.AddFile(file, client.GetConfig().Chunksize)
		if err != nil {
			return nil, "PrepareServerMessage : AddFile", err
		}
	}
	usermessage.Status.Sent = uint64(time.Now().UTC().Unix())
	usermessage.Status.AnswerToUuid = replyToUid

	// Store message
	err = peer.StoreMessage(usermessage, nil)
	if err != nil {
		return nil, "messageBuildPostprocess : StoreMessage", err
	}

	// Prepare cyphered + packed user message
	packedMsg, err := peer.ProcessOutboundUserMessage(usermessage)
	if err != nil {
		return nil, "messageBuildPostprocess : ProcessOutboundUserMessage", err
	}

	return packedMsg, "", nil
}

func BuildAckMessage(messageUid string, srvuid string, peer_uid string, received int64, processed int64) ([]byte, string, error) {

	peer := client.GetConfig().GetIdentity().Peers.GetFromUid(peer_uid)
	srv, err := client.GetConfig().GetIdentity().MessageServers.LoadServer(srvuid)
	if err != nil {
		return nil, "PrepareServerMessage : LoadServer", err
	}
	// Creating User message
	usermessage, err := peer.BuildSimpleUserMessage(nil)
	if err != nil {
		return nil, "PrepareServerMessage : BuildSimpleUserMessage", err
	}
	usermessage.Status.Uuid = messageUid
	usermessage.Status.Received = uint64(received)
	usermessage.Status.Processed = uint64(processed)
	// Prepare cyphered + packed user message
	packedMsg, err := peer.ProcessOutboundUserMessage(usermessage)
	if err != nil {
		return nil, "PrepareServerMessage : ProcessOutboundUserMessage", err
	}
	// Creating Server message for transporting the user message
	toServerMessage := srv.BuildToServerMessageFromUserMessage(packedMsg)
	data, err := srv.ProcessOutboundMessage(toServerMessage)
	if err != nil {
		return nil, "PrepareServerMessage : ProcessOutboundMessage", err
	}

	return data, "", nil
}

func ReadAckMessageResponse() {
	//! update the status in message store
}

// GetPeerLastMessageDbInfo returns the DB location of the most recently stored
// message for the given peer. Call this immediately after CreateAndStoreUserMessage
// to get the values needed for SendJob.MessageDbFile and SendJob.MessageDbId.
func GetPeerLastMessageDbInfo(peer_uid string) (dbFile string, dbId int64, errTxt string, err error) {
	peer := client.GetConfig().GetIdentity().Peers.GetFromUid(peer_uid)
	if peer == nil {
		return "", 0, "GetPeerLastMessageDbInfo: peer not found", errors.New("peer not found")
	}
	if peer.LastMessage == nil {
		return "", 0, "GetPeerLastMessageDbInfo: no message stored yet", errors.New("no message stored yet for this peer")
	}
	return peer.LastMessage.Dbfile, peer.LastMessage.Dbid, "", nil
}

// ProcessSentMessages scans every send queue under storagePath/queues/, updates
// the message storage entry with server delivery info for each sent job, then
// removes the job from the queue. Returns the number of messages updated.
//
// Each SendJob must have MessageDbFile and MessageDbId set (populated via
// GetPeerLastMessageDbInfo right after the message is stored).
func ProcessSentMessages(storagePath string) int {
	password, _ := client.GetConfig().GetMemPass()
	queueDir := filepath.Join(storagePath, "queues")
	entries, err := os.ReadDir(queueDir)
	if err != nil {
		logger.Warn().Err(err).Str("dir", queueDir).Msg("ProcessSentMessages: ReadDir")
		return 0
	}

	updated := 0

	for _, entry := range entries {
		if entry.IsDir() {
			continue
		}
		queue := entry.Name()

		jobs, err := client.GetSentJobs(storagePath, queue)
		if err != nil {
			logger.Error().Err(err).Str("queue", queue).Msg("ProcessSentMessages: GetSentJobs")
			continue
		}

		for _, job := range jobs {
			if job.SuccessfulServer == nil || job.SentAt == nil {
				// No delivery info – discard the job so it doesn't block the queue
				if err := client.DeleteSendJob(storagePath, queue, job.ID); err != nil {
					logger.Error().Err(err).Int64("id", job.ID).Msg("ProcessSentMessages: DeleteSendJob (incomplete)")
				}
				continue
			}

			if job.MessageDbFile == "" || job.MessageDbId == 0 {
				logger.Error().Int64("id", job.ID).Str("queue", queue).
					Msg("ProcessSentMessages: job missing MessageDbFile/MessageDbId — set them via GetPeerLastMessageDbInfo when building the SendJob")
				continue
			}

			serverUid := job.Servers[*job.SuccessfulServer].GetUid()
			receiveTime := uint64(job.SentAt.Unix())

			if err := client.SetMessageServerDelivery(job.MessageDbFile, job.MessageDbId, serverUid, receiveTime, password); err != nil {
				logger.Error().Err(err).Str("queue", queue).
					Str("dbFile", job.MessageDbFile).Int64("dbId", job.MessageDbId).
					Msg("ProcessSentMessages: SetMessageServerDelivery")
				continue
			}
			if err := client.DeleteSendJob(storagePath, queue, job.ID); err != nil {
				logger.Error().Err(err).Int64("id", job.ID).Msg("ProcessSentMessages: DeleteSendJob")
			}
			updated++
		}
	}
	return updated
}