package grpcapi

import (
	"context"
	"fmt"
	"io"
	"log"
	"net"
	"net/http"
	"sync"
	"time"

	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/metadata"
	"google.golang.org/grpc/status"
	"google.golang.org/protobuf/types/known/anypb"
	"google.golang.org/protobuf/types/known/emptypb"
	"google.golang.org/protobuf/types/known/timestamppb"

	"synapse/pkg/types"
)

// =============================================================================
// gRPC Server Implementation
// =============================================================================

// GRPCServer wraps the gRPC server and gateway
type GRPCServer struct {
	grpcServer *grpc.Server
	gateway    *http.Server
	mu         sync.RWMutex

	// Services
	taskService         *TaskServiceImpl
	messageService      *MessageServiceImpl
	capabilitiesService *CapabilitiesServiceImpl
	groupService        *GroupServiceImpl
	healthService       *HealthServiceImpl

	// Dependencies
	taskExecutor TaskExecutor
	msgRouter    MessageRouter
	capsProvider CapabilitiesProvider
	groupManager GroupManager
}

// TaskExecutor interface for task operations
type TaskExecutor interface {
	SubmitTask(ctx context.Context, taskType string, payload map[string]any, externalTaskID, priority, callbackURL, callbackToken string) (string, string, error)
	GetTaskStatus(ctx context.Context, taskID string) (*types.TaskInfo, error)
	ListTasks(ctx context.Context, status string, limit, offset int) ([]types.TaskInfo, int, error)
	CancelTask(ctx context.Context, taskID string) error
}

type MessageRouter interface {
	RouteMessage(ctx context.Context, msg *types.UnifiedSynapseMessage) (*types.UnifiedSynapseMessage, error)
}

type CapabilitiesProvider interface {
	GetCapabilities(ctx context.Context) (*types.AgentCapabilities, error)
}

type GroupManager interface {
	CreateGroup(ctx context.Context, name, description, coordinatorID string, initialMembers []string) (string, error)
	JoinGroup(ctx context.Context, groupID string, agent *types.AgentEndpoint) error
	LeaveGroup(ctx context.Context, groupID, agentID string) error
	DisbandGroup(ctx context.Context, groupID string) error
	ListMembers(ctx context.Context, groupID string) ([]types.GroupMember, error)

	// Voting operations
	InitiateVote(ctx context.Context, groupID, initiatorID, question string, options []string, threshold float64, timeoutSeconds int32) (string, error)
	SubmitVote(ctx context.Context, voteID, agentID, option, reason string) error
	GetVoteStatus(ctx context.Context, voteID string) (*VoteStatus, error)

	// Task split and merge
	SplitTask(ctx context.Context, groupID, taskID, taskType, requirements string, strategy SplitStrategy) ([]*SubtaskInfo, error)
	MergeResults(ctx context.Context, groupID, parentTaskID string, strategy MergeStrategy) (*anypb.Any, string, error)
}

// VoteStatus represents the status of a vote
type VoteStatus struct {
	VoteID        string
	Status        string // open, decided, expired
	Question      string
	TotalVotes    int
	RequiredVotes int
	WinningOption string
	Votes         map[string]string // agentID -> option
}

// =============================================================================
// Server Constructor
// =============================================================================

// NewGRPCServer creates a new gRPC server
func NewGRPCServer(taskExec TaskExecutor, msgRouter MessageRouter, capsProvider CapabilitiesProvider, groupManager GroupManager) *GRPCServer {
	return &GRPCServer{
		taskExecutor: taskExec,
		msgRouter:    msgRouter,
		capsProvider: capsProvider,
		groupManager: groupManager,
		taskService: &TaskServiceImpl{
			taskExecutor:  taskExec,
			streamClients: make(map[string]chan *TaskStatusUpdate),
		},
		messageService: &MessageServiceImpl{
			msgRouter: msgRouter,
		},
		capabilitiesService: &CapabilitiesServiceImpl{
			provider: capsProvider,
		},
		groupService: &GroupServiceImpl{
			groupManager: groupManager,
		},
		healthService: &HealthServiceImpl{},
	}
}

// Start starts both gRPC and gateway servers
func (s *GRPCServer) Start(grpcPort, gatewayPort int) error {
	// Start gRPC server
	go func() {
		lis, err := net.Listen("tcp", fmt.Sprintf(":%d", grpcPort))
		if err != nil {
			log.Fatalf("[gRPC] Failed to listen: %v", err)
		}

		// Create gRPC server with interceptors
		opts := []grpc.ServerOption{
			grpc.UnaryInterceptor(s.unaryInterceptor),
			grpc.StreamInterceptor(s.streamInterceptor),
		}
		s.grpcServer = grpc.NewServer(opts...)

		// Register services using ServiceDesc
		s.grpcServer.RegisterService(&TaskService_ServiceDesc, s.taskService)
		s.grpcServer.RegisterService(&A2AMessageService_ServiceDesc, s.messageService)
		s.grpcServer.RegisterService(&CapabilitiesService_ServiceDesc, s.capabilitiesService)
		s.grpcServer.RegisterService(&GroupService_ServiceDesc, s.groupService)
		s.grpcServer.RegisterService(&HealthService_ServiceDesc, s.healthService)

		log.Printf("[gRPC] Server started on port %d", grpcPort)
		if err := s.grpcServer.Serve(lis); err != nil {
			log.Fatalf("[gRPC] Failed to serve: %v", err)
		}
	}()

	// Start gRPC-Gateway
	go func() {
		_ = context.Background() // ctx reserved for future gateway handler registration
		mux := http.NewServeMux()

		// Register gateway handlers
		// Note: These would be generated from proto by grpc-gateway
		// err := RegisterTaskServiceHandlerFromEndpoint(ctx, mux, fmt.Sprintf("localhost:%d", grpcPort), opts)
		// ... etc

		s.gateway = &http.Server{
			Addr:    fmt.Sprintf(":%d", gatewayPort),
			Handler: mux,
		}

		log.Printf("[Gateway] HTTP server started on port %d", gatewayPort)
		if err := s.gateway.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("[Gateway] Failed to serve: %v", err)
		}
	}()

	return nil
}

// Stop gracefully stops both servers
func (s *GRPCServer) Stop() {
	if s.grpcServer != nil {
		s.grpcServer.GracefulStop()
	}
	if s.gateway != nil {
		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
		defer cancel()
		s.gateway.Shutdown(ctx)
	}
}

// =============================================================================
// Interceptors
// =============================================================================

func (s *GRPCServer) unaryInterceptor(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
	// Extract metadata
	md, ok := metadata.FromIncomingContext(ctx)
	if ok {
		// Check API key
		apiKeys := md.Get("x-api-key")
		if len(apiKeys) > 0 {
			// Validate API key
			log.Printf("[gRPC] API Key: %s", apiKeys[0])
		}
	}

	// Call handler
	return handler(ctx, req)
}

func (s *GRPCServer) streamInterceptor(srv interface{}, ss grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
	// Extract metadata
	md, ok := metadata.FromIncomingContext(ss.Context())
	if ok {
		apiKeys := md.Get("x-api-key")
		if len(apiKeys) > 0 {
			log.Printf("[gRPC Stream] API Key: %s", apiKeys[0])
		}
	}

	return handler(srv, ss)
}

// =============================================================================
// Task Service Implementation
// =============================================================================

type TaskServiceImpl struct {
	UnimplementedTaskServiceServer
	taskExecutor  TaskExecutor
	mu            sync.RWMutex
	streamClients map[string]chan *TaskStatusUpdate
}

func (s *TaskServiceImpl) SubmitTask(ctx context.Context, req *SubmitTaskRequest) (*SubmitTaskResponse, error) {
	// Convert payload
	payload := make(map[string]any)
	if req.Payload != nil {
		// Unpack Any to map
		// This would use protojson or similar
	}

	taskID, status, err := s.taskExecutor.SubmitTask(
		ctx,
		req.TaskType,
		payload,
		req.ExternalTaskId,
		req.Priority,
		req.CallbackUrl,
		req.CallbackToken,
	)
	if err != nil {
		return &SubmitTaskResponse{
			Success:   false,
			ErrorCode: "TASK_SUBMISSION_FAILED",
			Message:   err.Error(),
		}, nil
	}

	return &SubmitTaskResponse{
		Success: true,
		TaskId:  taskID,
		Status:  parseTaskStatus(status),
		Message: "任务已接收",
	}, nil
}

func (s *TaskServiceImpl) SubmitTaskWithFiles(ctx context.Context, req *SubmitTaskWithFilesRequest) (*SubmitTaskResponse, error) {
	// Handle file uploads
	// Convert files and call SubmitTask
	return s.SubmitTask(ctx, req.Request)
}

func (s *TaskServiceImpl) GetTask(ctx context.Context, req *GetTaskRequest) (*TaskStatusResponse, error) {
	task, err := s.taskExecutor.GetTaskStatus(ctx, req.TaskId)
	if err != nil {
		return &TaskStatusResponse{
			Success:      false,
			ErrorCode:    "TASK_NOT_FOUND",
			ErrorMessage: err.Error(),
		}, nil
	}

	return &TaskStatusResponse{
		Success: true,
		Task:    convertTaskInfo(task),
	}, nil
}

func (s *TaskServiceImpl) GetTaskStatus(ctx context.Context, req *GetTaskRequest) (*TaskStatusResponse, error) {
	return s.GetTask(ctx, req)
}

func (s *TaskServiceImpl) ListTasks(ctx context.Context, req *ListTasksRequest) (*ListTasksResponse, error) {
	tasks, total, err := s.taskExecutor.ListTasks(ctx, req.Status, int(req.Limit), int(req.Offset))
	if err != nil {
		return &ListTasksResponse{
			Success: false,
		}, err
	}

	var protoTasks []*TaskInfo
	for _, t := range tasks {
		protoTasks = append(protoTasks, convertTaskInfo(&t))
	}

	return &ListTasksResponse{
		Success: true,
		Tasks:   protoTasks,
		Total:   int32(total),
		Limit:   req.Limit,
		Offset:  req.Offset,
		HasMore: int(req.Offset+req.Limit) < total,
	}, nil
}

func (s *TaskServiceImpl) CancelTask(ctx context.Context, req *CancelTaskRequest) (*CancelTaskResponse, error) {
	if err := s.taskExecutor.CancelTask(ctx, req.TaskId); err != nil {
		return &CancelTaskResponse{
			Success: false,
			Message: err.Error(),
		}, nil
	}

	return &CancelTaskResponse{
		Success: true,
		TaskId:  req.TaskId,
		Status:  TaskStatus_TASK_STATUS_CANCELLED,
		Message: "任务已取消",
	}, nil
}

// StreamTaskStatus implements bidirectional streaming for task status updates
func (s *TaskServiceImpl) StreamTaskStatus(stream TaskService_StreamTaskStatusServer) error {
	// Register client
	clientID := fmt.Sprintf("stream-%d", time.Now().UnixNano())
	statusChan := make(chan *TaskStatusUpdate, 100)

	s.mu.Lock()
	s.streamClients[clientID] = statusChan
	s.mu.Unlock()

	defer func() {
		s.mu.Lock()
		delete(s.streamClients, clientID)
		s.mu.Unlock()
		close(statusChan)
	}()

	// Goroutine to send status updates
	go func() {
		for update := range statusChan {
			if err := stream.Send(update); err != nil {
				log.Printf("[gRPC Stream] Send error: %v", err)
				return
			}
		}
	}()

	// Receive subscription requests
	for {
		req, err := stream.Recv()
		if err == io.EOF {
			return nil
		}
		if err != nil {
			return err
		}

		if req.Subscribe {
			log.Printf("[gRPC Stream] Client %s subscribed to task %s", clientID, req.TaskId)
			// Start watching task status
			go s.watchTaskStatus(req.TaskId, statusChan)
		} else {
			log.Printf("[gRPC Stream] Client %s unsubscribed from task %s", clientID, req.TaskId)
		}
	}
}

func (s *TaskServiceImpl) watchTaskStatus(taskID string, ch chan *TaskStatusUpdate) {
	ticker := time.NewTicker(2 * time.Second)
	defer ticker.Stop()

	for range ticker.C {
		task, err := s.taskExecutor.GetTaskStatus(context.Background(), taskID)
		if err != nil {
			continue
		}

		ch <- &TaskStatusUpdate{
			TaskId:   taskID,
			Status:   parseTaskStatus(task.Status),
			Progress: int32(task.Progress),
			Message:  task.Message,
		}

		// Stop if terminal state
		if task.Status == "completed" || task.Status == "failed" || task.Status == "cancelled" {
			return
		}
	}
}

// =============================================================================
// Message Service Implementation
// =============================================================================

type MessageServiceImpl struct {
	UnimplementedA2AMessageServiceServer
	msgRouter MessageRouter
}

func (s *MessageServiceImpl) SendMessage(ctx context.Context, req *SendMessageRequest) (*SendMessageResponse, error) {
	// Convert proto message to internal format
	msg := convertProtoToInternalMessage(req.Message)

	resp, err := s.msgRouter.RouteMessage(ctx, msg)
	if err != nil {
		return &SendMessageResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &SendMessageResponse{
		Success:   true,
		MessageId: resp.ID,
	}, nil
}

// StreamMessages implements bidirectional streaming for Synapse messages
func (s *MessageServiceImpl) StreamMessages(stream A2AMessageService_StreamMessagesServer) error {
	ctx := stream.Context()
	clientID := fmt.Sprintf("msg-stream-%d", time.Now().UnixNano())

	log.Printf("[gRPC Stream] New message stream: %s", clientID)

	// Goroutine to receive messages
	go func() {
		for {
			msg, err := stream.Recv()
			if err == io.EOF {
				return
			}
			if err != nil {
				log.Printf("[gRPC Stream] Receive error: %v", err)
				return
			}

			internalMsg := convertProtoToInternalMessage(msg)
			resp, err := s.msgRouter.RouteMessage(ctx, internalMsg)
			if err != nil {
				log.Printf("[gRPC Stream] Route error: %v", err)
				continue
			}

			protoResp := convertInternalToProtoMessage(resp)
			if err := stream.Send(protoResp); err != nil {
				log.Printf("[gRPC Stream] Send error: %v", err)
				return
			}
		}
	}()

	// Keep stream alive
	<-ctx.Done()
	log.Printf("[gRPC Stream] Message stream closed: %s", clientID)
	return nil
}

func (s *MessageServiceImpl) ReceiveCallback(req *emptypb.Empty, stream A2AMessageService_ReceiveCallbackServer) error {
	// This would be used by agents to receive callback messages via gRPC stream
	// Implementation depends on callback routing mechanism
	return status.Error(codes.Unimplemented, "not implemented")
}

// =============================================================================
// Capabilities Service Implementation
// =============================================================================

type CapabilitiesServiceImpl struct {
	UnimplementedCapabilitiesServiceServer
	provider CapabilitiesProvider
}

func (s *CapabilitiesServiceImpl) GetCapabilities(ctx context.Context, req *emptypb.Empty) (*CapabilitiesResponse, error) {
	caps, err := s.provider.GetCapabilities(ctx)
	if err != nil {
		return &CapabilitiesResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &CapabilitiesResponse{
		Success:      true,
		Capabilities: convertAgentCapabilities(caps),
	}, nil
}

func (s *CapabilitiesServiceImpl) QueryAgent(ctx context.Context, req *QueryAgentRequest) (*CapabilitiesResponse, error) {
	// Query specific agent's capabilities
	return s.GetCapabilities(ctx, nil)
}

func (s *CapabilitiesServiceImpl) ListAgents(ctx context.Context, req *emptypb.Empty) (*ListAgentsResponse, error) {
	return &ListAgentsResponse{
		Success: true,
		Agents:  []*AgentInfo{},
	}, nil
}

// =============================================================================
// Group Service Implementation
// =============================================================================

type GroupServiceImpl struct {
	UnimplementedGroupServiceServer
	groupManager GroupManager
}

func (s *GroupServiceImpl) CreateGroup(ctx context.Context, req *CreateGroupRequest) (*CreateGroupResponse, error) {
	groupID, err := s.groupManager.CreateGroup(ctx, req.Name, req.Description, req.CoordinatorId, req.InitialMembers)
	if err != nil {
		return &CreateGroupResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &CreateGroupResponse{
		Success: true,
		GroupId: groupID,
		Group: &GroupInfo{
			Id:            groupID,
			Name:          req.Name,
			Description:   req.Description,
			CoordinatorId: req.CoordinatorId,
			Status:        "active",
			CreatedAt:     timestamppb.Now(),
		},
	}, nil
}

func (s *GroupServiceImpl) JoinGroup(ctx context.Context, req *JoinGroupRequest) (*JoinGroupResponse, error) {
	err := s.groupManager.JoinGroup(ctx, req.GroupId, convertProtoEndpoint(req.Agent))
	if err != nil {
		return &JoinGroupResponse{Success: false, Error: err.Error()}, nil
	}
	return &JoinGroupResponse{Success: true}, nil
}

func (s *GroupServiceImpl) LeaveGroup(ctx context.Context, req *LeaveGroupRequest) (*LeaveGroupResponse, error) {
	err := s.groupManager.LeaveGroup(ctx, req.GroupId, req.AgentId)
	if err != nil {
		return &LeaveGroupResponse{Success: false, Error: err.Error()}, nil
	}
	return &LeaveGroupResponse{Success: true}, nil
}

func (s *GroupServiceImpl) DisbandGroup(ctx context.Context, req *DisbandGroupRequest) (*DisbandGroupResponse, error) {
	err := s.groupManager.DisbandGroup(ctx, req.GroupId)
	if err != nil {
		return &DisbandGroupResponse{Success: false, Error: err.Error()}, nil
	}
	return &DisbandGroupResponse{Success: true}, nil
}

func (s *GroupServiceImpl) ListGroupMembers(ctx context.Context, req *ListGroupMembersRequest) (*ListGroupMembersResponse, error) {
	members, err := s.groupManager.ListMembers(ctx, req.GroupId)
	if err != nil {
		return &ListGroupMembersResponse{Success: false}, nil
	}

	var protoMembers []*GroupMember
	for _, m := range members {
		protoMembers = append(protoMembers, &GroupMember{
			AgentId:   m.AgentID,
			AgentName: m.AgentName,
			Role:      m.Role,
			Status:    string(m.Status),
			JoinedAt:  timestamppb.Now(),
		})
	}

	return &ListGroupMembersResponse{
		Success: true,
		Members: protoMembers,
	}, nil
}

// StreamGroupMessages implements bidirectional streaming for group messages
func (s *GroupServiceImpl) StreamGroupMessages(stream GroupService_StreamGroupMessagesServer) error {
	ctx := stream.Context()
	clientID := fmt.Sprintf("group-stream-%d", time.Now().UnixNano())

	log.Printf("[gRPC Stream] New group stream: %s", clientID)

	go func() {
		for {
			msg, err := stream.Recv()
			if err == io.EOF {
				return
			}
			if err != nil {
				log.Printf("[gRPC Stream] Receive error: %v", err)
				return
			}

			log.Printf("[gRPC Stream] Group message received: group=%s, type=%v", msg.GroupId, msg.Type)

			// Echo back for now
			if err := stream.Send(msg); err != nil {
				log.Printf("[gRPC Stream] Send error: %v", err)
				return
			}
		}
	}()

	<-ctx.Done()
	log.Printf("[gRPC Stream] Group stream closed: %s", clientID)
	return nil
}

// InitiateVote initiates a voting process in the group
func (s *GroupServiceImpl) InitiateVote(ctx context.Context, req *VoteRequest) (*VoteResponse, error) {
	voteID, err := s.groupManager.InitiateVote(ctx, req.GroupId, req.InitiatorId, req.Question, req.Options, req.Threshold, req.TimeoutSeconds)
	if err != nil {
		return &VoteResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &VoteResponse{
		Success: true,
		VoteId:  voteID,
	}, nil
}

// SubmitVote submits a vote in an ongoing voting process
func (s *GroupServiceImpl) SubmitVote(ctx context.Context, req *SubmitVoteRequest) (*SubmitVoteResponse, error) {
	err := s.groupManager.SubmitVote(ctx, req.VoteId, req.AgentId, req.Option, req.Reason)
	if err != nil {
		return &SubmitVoteResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &SubmitVoteResponse{
		Success: true,
	}, nil
}

// GetVoteStatus gets the current status of a vote
func (s *GroupServiceImpl) GetVoteStatus(ctx context.Context, req *GetVoteStatusRequest) (*VoteStatusResponse, error) {
	status, err := s.groupManager.GetVoteStatus(ctx, req.VoteId)
	if err != nil {
		return &VoteStatusResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &VoteStatusResponse{
		Success:       true,
		VoteId:        status.VoteID,
		Status:        status.Status,
		Question:      status.Question,
		TotalVotes:    int32(status.TotalVotes),
		RequiredVotes: int32(status.RequiredVotes),
		WinningOption: status.WinningOption,
	}, nil
}

// SplitTask splits a task into subtasks across group members
func (s *GroupServiceImpl) SplitTask(ctx context.Context, req *SplitTaskRequest) (*SplitTaskResponse, error) {
	subtasks, err := s.groupManager.SplitTask(ctx, req.GroupId, req.TaskId, req.TaskType, req.Requirements, req.Strategy)
	if err != nil {
		return &SplitTaskResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &SplitTaskResponse{
		Success:      true,
		GroupId:      req.GroupId,
		ParentTaskId: req.TaskId,
		Subtasks:     subtasks,
	}, nil
}

// MergeResults merges results from subtasks
func (s *GroupServiceImpl) MergeResults(ctx context.Context, req *MergeResultsRequest) (*MergeResultsResponse, error) {
	mergedResult, summary, err := s.groupManager.MergeResults(ctx, req.GroupId, req.ParentTaskId, req.Strategy)
	if err != nil {
		return &MergeResultsResponse{
			Success: false,
			Error:   err.Error(),
		}, nil
	}

	return &MergeResultsResponse{
		Success:      true,
		ParentTaskId: req.ParentTaskId,
		MergedResult: mergedResult,
		Summary:      summary,
	}, nil
}

// =============================================================================
// Health Service Implementation
// =============================================================================

type HealthServiceImpl struct {
	UnimplementedHealthServiceServer
}

func (s *HealthServiceImpl) HealthCheck(ctx context.Context, req *emptypb.Empty) (*HealthCheckResponse, error) {
	return &HealthCheckResponse{
		Status:        "healthy",
		Version:       "1.0.0",
		UptimeSeconds: 3600,
		ActiveTasks:   0,
	}, nil
}

// =============================================================================
// Conversion Helpers
// =============================================================================

func parseTaskStatus(status string) TaskStatus {
	switch status {
	case "received":
		return TaskStatus_TASK_STATUS_RECEIVED
	case "processing":
		return TaskStatus_TASK_STATUS_PROCESSING
	case "completed":
		return TaskStatus_TASK_STATUS_COMPLETED
	case "failed":
		return TaskStatus_TASK_STATUS_FAILED
	case "cancelled":
		return TaskStatus_TASK_STATUS_CANCELLED
	case "rejected":
		return TaskStatus_TASK_STATUS_REJECTED
	case "waiting":
		return TaskStatus_TASK_STATUS_WAITING
	default:
		return TaskStatus_TASK_STATUS_UNSPECIFIED
	}
}

func convertTaskInfo(task *types.TaskInfo) *TaskInfo {
	if task == nil {
		return nil
	}

	var result *anypb.Any
	if task.Result != nil {
		result, _ = anypb.New(&anypb.Any{Value: []byte(fmt.Sprintf("%v", task.Result))})
	}

	return &TaskInfo{
		Id:        task.ID,
		Type:      task.Type,
		Status:    parseTaskStatus(task.Status),
		Progress:  int32(task.Progress),
		Message:   task.Message,
		CreatedAt: timestamppb.Now(),
		UpdatedAt: timestamppb.Now(),
		Result:    result,
	}
}

func convertAgentCapabilities(caps *types.AgentCapabilities) *AgentCapabilities {
	if caps == nil {
		return nil
	}

	var taskTypes []*SupportedTaskType
	for _, tt := range caps.SupportedTaskTypes {
		taskTypes = append(taskTypes, &SupportedTaskType{
			Type:          tt.Type,
			Name:          tt.Name,
			Description:   tt.Description,
			EstimatedTime: tt.EstimatedTime,
			InputSchema:   tt.InputSchema,
			OutputSchema:  tt.OutputSchema,
			Capabilities:  tt.Capabilities,
		})
	}

	var transportModes []TransportMode
	for _, tm := range caps.SupportedTransportModes {
		transportModes = append(transportModes, TransportMode(TransportMode_value[string(tm)]))
	}

	return &AgentCapabilities{
		AgentId:                 caps.AgentID,
		AgentName:               caps.AgentName,
		SystemId:                caps.SystemID,
		ProtocolVersion:         caps.ProtocolVersion,
		SupportedTaskTypes:      taskTypes,
		SupportedContentTypes:   caps.SupportedContentTypes,
		SupportedTransportModes: transportModes,
		MaxFileSize:             caps.MaxFileSize,
		MaxConcurrentTasks:      int32(caps.MaxConcurrentTasks),
		MaxTaskDurationSeconds:  int32(caps.MaxTaskDuration),
		SupportProgressUpdates:  caps.SupportProgressUpdates,
		SupportStreaming:        caps.SupportStreaming,
		SupportHil:              caps.SupportHiL,
		SupportGroups:           caps.SupportGroups,
	}
}

func convertProtoToInternalMessage(msg *A2AMessage) *types.UnifiedSynapseMessage {
	if msg == nil {
		return nil
	}

	var payload []byte
	if msg.Payload != nil {
		payload = msg.Payload.Value
	}

	return &types.UnifiedSynapseMessage{
		ID:            msg.Id,
		Version:       msg.Version,
		Type:          string(MessageType_name[int32(msg.Type)]),
		Sender:        types.AgentEndpoint{AgentID: msg.Sender.AgentId},
		CorrelationID: msg.CorrelationId,
		ReplyTo:       msg.ReplyTo,
		GroupID:       msg.GroupId,
		Timestamp:     types.Timestamp(msg.Timestamp.AsTime().Format(time.RFC3339)),
		Payload:       payload,
		Signature:     msg.Signature,
	}
}

func convertInternalToProtoMessage(msg *types.UnifiedSynapseMessage) *A2AMessage {
	if msg == nil {
		return nil
	}

	var payload *anypb.Any
	if len(msg.Payload) > 0 {
		payload = &anypb.Any{Value: msg.Payload}
	}

	return &A2AMessage{
		Id:            msg.ID,
		Version:       msg.Version,
		Type:          MessageType(MessageType_value[msg.Type]),
		Sender:        &AgentEndpoint{AgentId: msg.Sender.AgentID},
		CorrelationId: msg.CorrelationID,
		ReplyTo:       msg.ReplyTo,
		GroupId:       msg.GroupID,
		Timestamp:     timestamppb.Now(),
		Payload:       payload,
		Signature:     msg.Signature,
	}
}

func convertProtoEndpoint(endpoint *AgentEndpoint) *types.AgentEndpoint {
	if endpoint == nil {
		return nil
	}
	return &types.AgentEndpoint{
		AgentID:   endpoint.AgentId,
		AgentName: endpoint.AgentName,
		SystemID:  endpoint.SystemId,
		Endpoint:  endpoint.Endpoint,
		Version:   endpoint.Version,
	}
}