package notify

import itransfer "b612.me/notify/internal/transfer"

type fileTransferState struct {
	monitor *fileTransferMonitor
	query   fileTransferQuery
	runtime *transferRuntime
}

func newFileTransferState() *fileTransferState {
	return newFileTransferStateWithConfig(defaultFileTransferConfig())
}

func newFileTransferStateWithConfig(cfg fileTransferConfig) *fileTransferState {
	monitor := newFileTransferMonitorWithConfig(cfg)
	return &fileTransferState{
		monitor: monitor,
		query:   newFileTransferQuery(monitor),
		runtime: newTransferRuntime(),
	}
}

func (s *fileTransferState) observe(direction fileTransferDirection, event FileEvent) {
	if s == nil || s.monitor == nil {
		return
	}
	s.monitor.observe(direction, event)
	s.observeRuntime(direction, event)
}

func (s *fileTransferState) observeMonitorOnly(direction fileTransferDirection, event FileEvent) {
	if s == nil || s.monitor == nil {
		return
	}
	s.monitor.observe(direction, event)
}

func (s *fileTransferState) applyConfig(cfg fileTransferConfig) {
	if s == nil || s.monitor == nil {
		return
	}
	s.monitor.applyConfig(cfg)
}

func (s *fileTransferState) monitorView() *fileTransferMonitor {
	if s == nil {
		return nil
	}
	return s.monitor
}

func (s *fileTransferState) active() fileTransferSummaryGroup {
	if s == nil {
		return fileTransferSummaryGroup{}
	}
	return s.query.active()
}

func (s *fileTransferState) completed() fileTransferSummaryGroup {
	if s == nil {
		return fileTransferSummaryGroup{}
	}
	return s.query.completed()
}

func (s *fileTransferState) failed() fileTransferSummaryGroup {
	if s == nil {
		return fileTransferSummaryGroup{}
	}
	return s.query.failed()
}

func (s *fileTransferState) latest(direction fileTransferDirection, scope string, fileID string) (fileTransferSummary, bool) {
	if s == nil || s.monitor == nil {
		return fileTransferSummary{}, false
	}
	return s.monitor.latestSummary(direction, scope, fileID)
}

func (s *fileTransferState) latestByFileID(fileID string) fileTransferSummaryGroup {
	if s == nil {
		return fileTransferSummaryGroup{}
	}
	return s.query.latestByFileID(fileID)
}

func (s *fileTransferState) latestSendByFileID(fileID string) []fileTransferSummary {
	if s == nil {
		return nil
	}
	return s.query.latestSendByFileID(fileID)
}

func (s *fileTransferState) latestReceiveByFileID(fileID string) []fileTransferSummary {
	if s == nil {
		return nil
	}
	return s.query.latestReceiveByFileID(fileID)
}

func (s *fileTransferState) latestByFileIDQuery(fileID string, query fileTransferSummaryQuery) fileTransferSummaryGroup {
	if s == nil {
		return fileTransferSummaryGroup{}
	}
	return s.query.latestByFileIDQuery(fileID, query)
}

func (s *fileTransferState) latestSendByFileIDQuery(fileID string, query fileTransferSummaryQuery) []fileTransferSummary {
	if s == nil {
		return nil
	}
	return s.query.latestSendByFileIDQuery(fileID, query)
}

func (s *fileTransferState) latestReceiveByFileIDQuery(fileID string, query fileTransferSummaryQuery) []fileTransferSummary {
	if s == nil {
		return nil
	}
	return s.query.latestReceiveByFileIDQuery(fileID, query)
}

func (s *fileTransferState) observeRuntime(direction fileTransferDirection, event FileEvent) {
	if s == nil || s.runtime == nil || event.Packet.FileID == "" {
		return
	}
	runtimeScope := transferRuntimeScopeForEvent(event)
	publicScope := transferRuntimePublicScopeForEvent(event)
	transportGeneration := transferRuntimeTransportGenerationForEvent(event)
	s.ensureRuntimeTransfer(direction, runtimeScope, publicScope, transportGeneration, event)
	s.recordRuntimeStage(direction, runtimeScope, event.Packet.FileID, runtimeTransferStageForEvent(event))
	switch event.Kind {
	case EnvelopeFileChunk:
		s.runtime.activate(direction, runtimeScope, event.Packet.FileID)
		s.syncRuntimeProgress(direction, runtimeScope, event)
	case EnvelopeFileEnd:
		s.runtime.activate(direction, runtimeScope, event.Packet.FileID)
		s.syncRuntimeProgress(direction, runtimeScope, event)
		switch direction {
		case fileTransferDirectionSend:
			s.runtime.beginCommit(direction, runtimeScope, event.Packet.FileID)
		case fileTransferDirectionReceive:
			s.runtime.beginVerify(direction, runtimeScope, event.Packet.FileID)
		}
		s.runtime.complete(direction, runtimeScope, event.Packet.FileID)
	case EnvelopeFileAbort:
		s.syncRuntimeProgress(direction, runtimeScope, event)
		s.recordRuntimeFailureStage(direction, runtimeScope, event.Packet.FileID, event.Packet.Stage)
		s.runtime.abort(direction, runtimeScope, event.Packet.FileID, event.Err)
	}
}

func (s *fileTransferState) ensureRuntimeTransfer(direction fileTransferDirection, runtimeScope string, publicScope string, transportGeneration uint64, event FileEvent) {
	if s == nil || s.runtime == nil || event.Packet.FileID == "" {
		return
	}
	s.runtime.ensureTransferDescriptor(direction, runtimeScope, publicScope, transportGeneration, itransfer.Descriptor{
		ID:       event.Packet.FileID,
		Channel:  itransfer.DataChannel,
		Size:     event.Packet.Size,
		Checksum: event.Packet.Checksum,
		Metadata: buildKernelTransferMetadata(event),
	})
}

func (s *fileTransferState) startRuntimeSendSession(runtimeScope string, publicScope string, transportGeneration uint64, session *fileSendSession) {
	if s == nil || s.runtime == nil || session == nil || session.fileID == "" {
		return
	}
	s.runtime.ensureTransferDescriptor(fileTransferDirectionSend, runtimeScope, publicScope, transportGeneration, itransfer.Descriptor{
		ID:       session.fileID,
		Channel:  itransfer.DataChannel,
		Size:     session.size,
		Checksum: session.checksum,
		Metadata: itransfer.Metadata{
			"name": session.name,
			"path": session.path,
		},
	})
}

func buildKernelTransferMetadata(event FileEvent) itransfer.Metadata {
	metadata := make(itransfer.Metadata)
	if event.Packet.Name != "" {
		metadata["name"] = event.Packet.Name
	}
	if event.Path != "" {
		metadata["path"] = event.Path
	}
	if len(metadata) == 0 {
		return nil
	}
	return metadata
}

func (s *fileTransferState) syncRuntimeProgress(direction fileTransferDirection, scope string, event FileEvent) {
	if s == nil || s.runtime == nil {
		return
	}
	snapshot, ok := s.runtimeSnapshot(direction, scope, event.Packet.FileID)
	if !ok {
		return
	}
	progress := event.Received
	if progress < 0 {
		progress = 0
	}
	switch direction {
	case fileTransferDirectionReceive:
		if delta := progress - snapshot.ReceivedBytes; delta > 0 {
			s.runtime.recordReceive(direction, scope, event.Packet.FileID, delta)
		}
	default:
		if delta := progress - snapshot.SentBytes; delta > 0 {
			s.runtime.recordSend(direction, scope, event.Packet.FileID, delta)
		}
		s.runtime.setAckedBytes(direction, scope, event.Packet.FileID, progress)
	}
}

func (s *fileTransferState) recordRuntimeRetry(direction fileTransferDirection, scope string, fileID string) {
	if s == nil || s.runtime == nil || fileID == "" {
		return
	}
	s.runtime.recordRetry(direction, scope, fileID)
}

func (s *fileTransferState) recordRuntimeTimeout(direction fileTransferDirection, scope string, fileID string) {
	if s == nil || s.runtime == nil || fileID == "" {
		return
	}
	s.runtime.recordTimeout(direction, scope, fileID)
}

func (s *fileTransferState) recordRuntimeStage(direction fileTransferDirection, scope string, fileID string, stage string) {
	if s == nil || s.runtime == nil || fileID == "" || stage == "" {
		return
	}
	s.runtime.recordStage(direction, scope, fileID, stage)
}

func (s *fileTransferState) recordRuntimeFailureStage(direction fileTransferDirection, scope string, fileID string, stage string) {
	if s == nil || s.runtime == nil || fileID == "" || stage == "" {
		return
	}
	s.runtime.recordFailureStage(direction, scope, fileID, stage)
}

func (s *fileTransferState) runtimeSnapshot(direction fileTransferDirection, scope string, transferID string) (itransfer.Snapshot, bool) {
	if s == nil || s.runtime == nil || transferID == "" {
		return itransfer.Snapshot{}, false
	}
	return s.runtime.snapshot(direction, scope, transferID)
}

func transferRuntimeScopeForEvent(event FileEvent) string {
	if event.TransportConn != nil {
		return serverTransportScopeForTransport(event.TransportConn)
	}
	if logical := fileEventLogicalConnSnapshot(event); logical != nil {
		return serverTransportScope(logical)
	}
	return clientFileScope()
}

func transferRuntimePublicScopeForEvent(event FileEvent) string {
	return fileTransferMonitorScope(event)
}

func transferRuntimeTransportGenerationForEvent(event FileEvent) uint64 {
	if event.TransportConn != nil {
		return event.TransportConn.TransportGeneration()
	}
	logical := fileEventLogicalConnSnapshot(event)
	if logical == nil {
		return 0
	}
	return logical.transportGenerationSnapshot()
}

func runtimeTransferStageForEvent(event FileEvent) string {
	if event.Packet.Stage != "" {
		return event.Packet.Stage
	}
	return fileStageByKind(event.Kind)
}

func (c *ClientCommon) getTransferRuntime() *transferRuntime {
	return c.getFileTransferState().runtime
}

func (s *ServerCommon) getTransferRuntime() *transferRuntime {
	return s.getFileTransferState().runtime
}

func (c *ClientCommon) getFileTransferState() *fileTransferState {
	return c.getLogicalSessionState().fileTransfers
}

func (s *ServerCommon) getFileTransferState() *fileTransferState {
	return s.getLogicalSessionState().fileTransfers
}