package gateway

import (
	"bytes"
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"git.dcentral.systems/toolz/goplt/pkg/services"
	"github.com/gin-gonic/gin"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

func TestGateway_handleLogin(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		requestBody    interface{}
		clientResp     *services.TokenResponse
		clientErr      error
		expectedStatus int
		expectedBody   func(*testing.T, *httptest.ResponseRecorder)
	}{
		{
			name: "successful login",
			requestBody: map[string]string{
				"email":    "test@example.com",
				"password": "password123",
			},
			clientResp: &services.TokenResponse{
				AccessToken:  "access-token",
				RefreshToken: "refresh-token",
				ExpiresIn:    3600,
				TokenType:    "Bearer",
			},
			clientErr:      nil,
			expectedStatus: http.StatusOK,
			expectedBody: func(t *testing.T, w *httptest.ResponseRecorder) {
				var resp services.TokenResponse
				err := json.Unmarshal(w.Body.Bytes(), &resp)
				require.NoError(t, err)
				assert.Equal(t, "access-token", resp.AccessToken)
				assert.Equal(t, "refresh-token", resp.RefreshToken)
			},
		},
		{
			name: "invalid request body",
			requestBody: map[string]string{
				"email": "test@example.com",
				// missing password
			},
			expectedStatus: http.StatusBadRequest,
		},
		{
			name: "client error - unauthorized",
			requestBody: map[string]string{
				"email":    "test@example.com",
				"password": "wrongpassword",
			},
			clientErr:      status.Error(codes.Unauthenticated, "invalid credentials"),
			expectedStatus: http.StatusUnauthorized,
		},
		{
			name: "client error - internal",
			requestBody: map[string]string{
				"email":    "test@example.com",
				"password": "password123",
			},
			clientErr:      status.Error(codes.Internal, "internal error"),
			expectedStatus: http.StatusInternalServerError,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mockClient := &mockAuthClient{
				loginResp: tt.clientResp,
				loginErr:  tt.clientErr,
			}

			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.POST("/login", func(c *gin.Context) {
				gateway.handleLogin(context.Background(), c, mockClient)
			})

			bodyBytes, _ := json.Marshal(tt.requestBody)
			req := httptest.NewRequest(http.MethodPost, "/login", bytes.NewReader(bodyBytes))
			req.Header.Set("Content-Type", "application/json")
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)
			if tt.expectedBody != nil {
				tt.expectedBody(t, w)
			}
		})
	}
}

func TestGateway_handleRefreshToken(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		requestBody    interface{}
		clientResp     *services.TokenResponse
		clientErr      error
		expectedStatus int
	}{
		{
			name: "successful refresh",
			requestBody: map[string]string{
				"refresh_token": "refresh-token-123",
			},
			clientResp: &services.TokenResponse{
				AccessToken:  "new-access-token",
				RefreshToken: "new-refresh-token",
				ExpiresIn:    3600,
				TokenType:    "Bearer",
			},
			expectedStatus: http.StatusOK,
		},
		{
			name:        "invalid request body",
			requestBody: map[string]string{
				// missing refresh_token
			},
			expectedStatus: http.StatusBadRequest,
		},
		{
			name: "client error",
			requestBody: map[string]string{
				"refresh_token": "invalid-token",
			},
			clientErr:      status.Error(codes.Unauthenticated, "invalid token"),
			expectedStatus: http.StatusUnauthorized,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mockClient := &mockAuthClient{
				refreshResp: tt.clientResp,
				refreshErr:  tt.clientErr,
			}

			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.POST("/refresh", func(c *gin.Context) {
				gateway.handleRefreshToken(context.Background(), c, mockClient)
			})

			bodyBytes, _ := json.Marshal(tt.requestBody)
			req := httptest.NewRequest(http.MethodPost, "/refresh", bytes.NewReader(bodyBytes))
			req.Header.Set("Content-Type", "application/json")
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)
		})
	}
}

func TestGateway_handleValidateToken(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		requestBody    interface{}
		clientResp     *services.TokenClaims
		clientErr      error
		expectedStatus int
	}{
		{
			name: "successful validation",
			requestBody: map[string]string{
				"token": "valid-token",
			},
			clientResp: &services.TokenClaims{
				UserID:    "user-123",
				Email:     "test@example.com",
				Roles:     []string{"user"},
				ExpiresAt: 1234567890,
			},
			expectedStatus: http.StatusOK,
		},
		{
			name:        "invalid request body",
			requestBody: map[string]string{
				// missing token
			},
			expectedStatus: http.StatusBadRequest,
		},
		{
			name: "client error - invalid token",
			requestBody: map[string]string{
				"token": "invalid-token",
			},
			clientErr:      status.Error(codes.Unauthenticated, "invalid token"),
			expectedStatus: http.StatusUnauthorized,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mockClient := &mockAuthClient{
				validateResp: tt.clientResp,
				validateErr:  tt.clientErr,
			}

			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.POST("/validate", func(c *gin.Context) {
				gateway.handleValidateToken(context.Background(), c, mockClient)
			})

			bodyBytes, _ := json.Marshal(tt.requestBody)
			req := httptest.NewRequest(http.MethodPost, "/validate", bytes.NewReader(bodyBytes))
			req.Header.Set("Content-Type", "application/json")
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)
		})
	}
}

func TestGateway_handleLogout(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		requestBody    interface{}
		clientErr      error
		expectedStatus int
	}{
		{
			name: "successful logout",
			requestBody: map[string]string{
				"refresh_token": "refresh-token-123",
			},
			expectedStatus: http.StatusOK,
		},
		{
			name:        "invalid request body",
			requestBody: map[string]string{
				// missing refresh_token
			},
			expectedStatus: http.StatusBadRequest,
		},
		{
			name: "client error",
			requestBody: map[string]string{
				"refresh_token": "invalid-token",
			},
			clientErr:      status.Error(codes.NotFound, "token not found"),
			expectedStatus: http.StatusNotFound,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mockClient := &mockAuthClient{
				logoutErr: tt.clientErr,
			}

			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.POST("/logout", func(c *gin.Context) {
				gateway.handleLogout(context.Background(), c, mockClient)
			})

			bodyBytes, _ := json.Marshal(tt.requestBody)
			req := httptest.NewRequest(http.MethodPost, "/logout", bytes.NewReader(bodyBytes))
			req.Header.Set("Content-Type", "application/json")
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)
		})
	}
}

func TestGateway_handleGetUser(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		userID         string
		clientResp     *services.User
		clientErr      error
		expectedStatus int
	}{
		{
			name:   "successful get user",
			userID: "user-123",
			clientResp: &services.User{
				ID:        "user-123",
				Email:     "test@example.com",
				Username:  "testuser",
				FirstName: "Test",
				LastName:  "User",
			},
			expectedStatus: http.StatusOK,
		},
		{
			name:           "client error - not found",
			userID:         "nonexistent",
			clientErr:      status.Error(codes.NotFound, "user not found"),
			expectedStatus: http.StatusNotFound,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mockClient := &mockIdentityClient{
				getUserResp: tt.clientResp,
				getUserErr:  tt.clientErr,
			}

			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.GET("/users/:id", func(c *gin.Context) {
				gateway.handleGetUser(context.Background(), c, mockClient, tt.userID)
			})

			req := httptest.NewRequest(http.MethodGet, "/users/"+tt.userID, nil)
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)
		})
	}
}

func TestGateway_handleCreateUser(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		requestBody    interface{}
		clientResp     *services.User
		clientErr      error
		expectedStatus int
	}{
		{
			name: "successful create",
			requestBody: services.CreateUserRequest{
				Email:     "test@example.com",
				Username:  "testuser",
				Password:  "password123",
				FirstName: "Test",
				LastName:  "User",
			},
			clientResp: &services.User{
				ID:        "user-123",
				Email:     "test@example.com",
				Username:  "testuser",
				FirstName: "Test",
				LastName:  "User",
			},
			expectedStatus: http.StatusCreated,
		},
		{
			name:           "invalid JSON",
			requestBody:    "not a json object",
			expectedStatus: http.StatusBadRequest,
		},
		{
			name: "client error - already exists",
			requestBody: services.CreateUserRequest{
				Email:    "existing@example.com",
				Username: "existing",
				Password: "password123",
			},
			clientErr:      status.Error(codes.AlreadyExists, "user already exists"),
			expectedStatus: http.StatusConflict,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			mockClient := &mockIdentityClient{
				createUserResp: tt.clientResp,
				createUserErr:  tt.clientErr,
			}

			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.POST("/users", func(c *gin.Context) {
				gateway.handleCreateUser(context.Background(), c, mockClient)
			})

			bodyBytes, _ := json.Marshal(tt.requestBody)
			req := httptest.NewRequest(http.MethodPost, "/users", bytes.NewReader(bodyBytes))
			req.Header.Set("Content-Type", "application/json")
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)
		})
	}
}

func TestGateway_handleGRPCError(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name           string
		err            error
		expectedStatus int
		expectedError  string
	}{
		{
			name:           "Unauthenticated",
			err:            status.Error(codes.Unauthenticated, "invalid token"),
			expectedStatus: http.StatusUnauthorized,
			expectedError:  "Unauthorized",
		},
		{
			name:           "PermissionDenied",
			err:            status.Error(codes.PermissionDenied, "access denied"),
			expectedStatus: http.StatusForbidden,
			expectedError:  "Forbidden",
		},
		{
			name:           "NotFound",
			err:            status.Error(codes.NotFound, "resource not found"),
			expectedStatus: http.StatusNotFound,
			expectedError:  "Not found",
		},
		{
			name:           "InvalidArgument",
			err:            status.Error(codes.InvalidArgument, "invalid input"),
			expectedStatus: http.StatusBadRequest,
			expectedError:  "Invalid request",
		},
		{
			name:           "AlreadyExists",
			err:            status.Error(codes.AlreadyExists, "resource exists"),
			expectedStatus: http.StatusConflict,
			expectedError:  "Resource already exists",
		},
		{
			name:           "Internal",
			err:            status.Error(codes.Internal, "internal error"),
			expectedStatus: http.StatusInternalServerError,
			expectedError:  "Internal server error",
		},
		{
			name:           "Unavailable",
			err:            status.Error(codes.Unavailable, "service unavailable"),
			expectedStatus: http.StatusServiceUnavailable,
			expectedError:  "Service unavailable",
		},
		{
			name:           "non-gRPC error",
			err:            assert.AnError,
			expectedStatus: http.StatusInternalServerError,
			expectedError:  "Internal server error",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			gateway := &Gateway{
				log: &mockLogger{},
			}

			router := gin.New()
			router.GET("/test", func(c *gin.Context) {
				gateway.handleGRPCError(c, tt.err)
			})

			req := httptest.NewRequest(http.MethodGet, "/test", nil)
			w := httptest.NewRecorder()

			router.ServeHTTP(w, req)

			assert.Equal(t, tt.expectedStatus, w.Code)

			var response map[string]interface{}
			err := json.Unmarshal(w.Body.Bytes(), &response)
			require.NoError(t, err)
			assert.Equal(t, tt.expectedError, response["error"])
		})
	}
}