//ValidateEventTrackingPayloadHandler validates that the payload has a valid JSON Schema
//Uses a FinalHandler as next because it consumes the request's body
func ValidateEventTrackingPayloadHandler(next *ctx.FinalHandler) *ctx.Handler {
	return ctx.NewHandler(next.Context, func(c *ctx.Context, w http.ResponseWriter, r *http.Request) {
		//Validate the payload
		body, err := ioutil.ReadAll(r.Body)
		if err != nil {
			c.Logger.Errorf("%s : Error reading body: %s", utilities.GetIP(r), err.Error())
			http.Error(w, http.StatusText(500), 500)
			return
		}
		next.Payload = body
		requestLoader := gojsonschema.NewStringLoader(string(body))

		result, err := c.JSONTrackingEventValidator.Schema.Validate(requestLoader)
		if err != nil {
			c.Logger.Infof("%s : Json validation error: %s", utilities.GetIP(r), err.Error())
			http.Error(w, http.StatusText(400), 400)
			return
		}

		if !result.Valid() {
			c.Logger.Infof("%s : Payload is not valid: %+v", utilities.GetIP(r), result.Errors())
			http.Error(w, http.StatusText(400), 400)
			return
		}
		next.ServeHTTP(w, r)
	})
}
//AuthHandler middleware
//This handler handles auth based on the assertion that the request is valid JSON
//Verifies for access, blocks handlers chain if access denied
func AuthHandler(next *ctx.Handler) *ctx.Handler {
	return ctx.NewHandler(next.Context, func(c *ctx.Context, w http.ResponseWriter, r *http.Request) {
		//TODO: This can change for body instead ?
		token := r.Header.Get("Tracking-Token")
		//Bad request token empty or not present
		if token == "" {
			c.Logger.Infof("%s : No token header", utilities.GetIP(r))
			token = r.URL.Query().Get("key")
			if token == "" {
				c.Logger.Infof("%s : No token query parameter", utilities.GetIP(r))
				http.Error(w, http.StatusText(400), 400)
				return
			}
		}

		authorized, err := c.AuthDb.IsTokenAuthorized(token)

		// Internal server error TODO: Handle this
		if err != nil {
			c.Logger.Errorf("%s : Error while authorizing: %s", utilities.GetIP(r), err.Error())
			http.Error(w, http.StatusText(500), 500)
			return
		}
		// Unauthorized
		if !authorized {
			c.Logger.Warnf("%s : Unauthorized: %s", utilities.GetIP(r), token)
			http.Error(w, http.StatusText(401), 401)
			return
		}
		c.Logger.Infof("%s : Authorized", utilities.GetIP(r))
		next.ServeHTTP(w, r)
	})
}
func init() {
	mockedDb, err := sqlmock.New()
	if err != nil {
		log.Fatalf("An error: %s, was not expected when opening a stub database connection", err.Error())
	}

	columns := []string{"exists"}
	sqlmock.ExpectQuery("SELECT EXISTS\\(SELECT id FROM api_tokens WHERE token = (.+)\\)").
		WithArgs("123").
		WillReturnRows(sqlmock.NewRows(columns).AddRow(false))

	sqlmock.ExpectQuery("SELECT EXISTS\\(SELECT id FROM api_tokens WHERE token = (.+)\\)").
		WithArgs("456").
		WillReturnRows(sqlmock.NewRows(columns).AddRow(true))

	trackingValidator, err := validators.NewJSONEventTrackingValidator()
	if err != nil {
		log.Fatalf("An error: %s, was not expected when initializing tracking validator", err.Error())
	}

	router = mux.NewRouter()
	context := ctx.NewContext(datastores.NewAuthInstance(mockedDb), nil, nil, trackingValidator, "DEV")
	testHandler := ctx.NewHandler(context, testHandle)
	testFinalHander := ctx.NewFinalHandler(context, []byte(""), testFinalHandle)

	router.Handle("/testEnforceJSON", middlewares.EnforceJSONHandler(testHandler))
	router.Handle("/testAuth", middlewares.AuthHandler(testHandler))
	router.Handle("/testValidateEventTrackingPayloadHandler", middlewares.ValidateEventTrackingPayloadHandler(testFinalHander))

	server = httptest.NewServer(router)

	testEnforceJSONUrl = fmt.Sprintf("%s/testEnforceJSON", server.URL)
	testAuthUrl = fmt.Sprintf("%s/testAuth", server.URL)
	testValidateEventTrackingPayloadHandlerUrl = fmt.Sprintf("%s/testValidateEventTrackingPayloadHandler", server.URL)
}
//EnforceJSONHandler middleware
//This handler can handle raw requests
//This handler checks for detected content type as well as content-type header
func EnforceJSONHandler(next *ctx.Handler) *ctx.Handler {
	return ctx.NewHandler(next.Context, func(c *ctx.Context, w http.ResponseWriter, r *http.Request) {
		//Ensure that there is a body
		if r.ContentLength == 0 {
			c.Logger.Infof("%s : Recieved empty payload", utilities.GetIP(r))
			http.Error(w, http.StatusText(400), 400)
			return
		}
		//Ensure that its json
		contentType := r.Header.Get("Content-Type")
		if contentType != "application/json; charset=UTF-8" {
			c.Logger.Infof("%s : Invalid content type. Got %s", utilities.GetIP(r), contentType)
			http.Error(w, http.StatusText(415), 415)
			return
		}
		next.ServeHTTP(w, r)
	})
}