package roomclient

import (
	"context"
	"fmt"
	"strings"
	"time"

	"hyapp-admin-server/internal/appctx"
	roomv1 "hyapp.local/api/proto/room/v1"

	"google.golang.org/grpc"
)

type Client interface {
	CloseRoom(ctx context.Context, req CloseRoomRequest) (*CloseRoomResult, error)
	ReopenRoom(ctx context.Context, req ReopenRoomRequest) (*CloseRoomResult, error)
}

type CloseRoomRequest struct {
	RequestID   string
	RoomID      string
	ActorUserID int64
	Reason      string
}

type CloseRoomResult struct {
	Applied       bool
	RoomVersion   int64
	ServerTimeMs  int64
	RoomStatus    string
	OnlineUserNum int
}

type ReopenRoomRequest struct {
	RequestID   string
	RoomID      string
	ActorUserID int64
}

type GRPCClient struct {
	client roomv1.RoomCommandServiceClient
}

func NewGRPC(conn grpc.ClientConnInterface) *GRPCClient {
	return &GRPCClient{client: roomv1.NewRoomCommandServiceClient(conn)}
}

func (c *GRPCClient) CloseRoom(ctx context.Context, req CloseRoomRequest) (*CloseRoomResult, error) {
	return c.setRoomLifecycle(ctx, req.RequestID, req.RoomID, req.ActorUserID, firstNonEmpty(req.Reason, "admin_closed"))
}

func (c *GRPCClient) ReopenRoom(ctx context.Context, req ReopenRoomRequest) (*CloseRoomResult, error) {
	return c.setRoomLifecycle(ctx, req.RequestID, req.RoomID, req.ActorUserID, "admin_reopen")
}

func (c *GRPCClient) setRoomLifecycle(ctx context.Context, rawRequestID string, rawRoomID string, actorUserID int64, rawReason string) (*CloseRoomResult, error) {
	if c == nil || c.client == nil {
		return nil, fmt.Errorf("room service client is not configured")
	}
	roomID := strings.TrimSpace(rawRoomID)
	reason := strings.TrimSpace(rawReason)
	if roomID == "" || actorUserID <= 0 || reason == "" {
		return nil, fmt.Errorf("room lifecycle request is incomplete")
	}
	requestID := strings.TrimSpace(rawRequestID)
	if requestID == "" {
		requestID = fmt.Sprintf("admin-room-lifecycle-%s-%d", roomID, time.Now().UnixMilli())
	}
	resp, err := c.client.CloseRoom(ctx, &roomv1.CloseRoomRequest{
		Meta: &roomv1.RequestMeta{
			RequestId:   requestID,
			CommandId:   commandID(requestID, reason, roomID),
			ActorUserId: actorUserID,
			RoomId:      roomID,
			AppCode:     appctx.FromContext(ctx),
			SentAtMs:    time.Now().UnixMilli(),
		},
		Reason: reason,
	})
	if err != nil {
		return nil, err
	}
	result := resp.GetResult()
	room := resp.GetRoom()
	return &CloseRoomResult{
		Applied:       result.GetApplied(),
		RoomVersion:   result.GetRoomVersion(),
		ServerTimeMs:  result.GetServerTimeMs(),
		RoomStatus:    room.GetStatus(),
		OnlineUserNum: len(room.GetOnlineUsers()),
	}, nil
}

func commandID(requestID string, reason string, roomID string) string {
	base := strings.TrimSpace(requestID)
	if base == "" {
		base = fmt.Sprintf("admin-room-lifecycle-%d", time.Now().UnixMilli())
	}
	value := base + ":" + strings.TrimSpace(reason) + ":" + strings.TrimSpace(roomID)
	if len(value) <= 128 {
		return value
	}
	return value[:128]
}

func firstNonEmpty(values ...string) string {
	for _, value := range values {
		if strings.TrimSpace(value) != "" {
			return value
		}
	}
	return ""
}