feat(validation): Implement form validation and error handling utilities

- Add validation rules for form fields with XSS protection
- Create API error handler to parse and manage server validation errors
- Integrate validation rules into contact and inquiries forms
- Enhance error handling with user feedback for form submissions
- Introduce unit tests for validation and error handling functionalities

lib/__tests__/apiErrorHandler.test.ts

@@ -0,0 +1,210 @@
+import { AxiosError } from "axios";
+import { handleApiError, parseApiError } from "../apiErrorHandler";
+
+describe("API Error Handler", () => {
+  describe("parseApiError", () => {
+    it("should return default message for non-Error objects", () => {
+      const result = parseApiError("string error");
+      expect(result.generalMessage).toBe("Something went wrong. Please try again.");
+      expect(result.fieldErrors).toEqual({});
+    });
+
+    it("should handle network errors (no response)", () => {
+      const error = new Error("Network Error") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = undefined;
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toContain("Unable to connect");
+    });
+
+    it("should parse 400 errors with field-level errors", () => {
+      const error = new Error("Bad Request") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 400,
+        data: {
+          errors: {
+            email: "Invalid email format",
+            full_name: ["Name is too short", "Name contains invalid characters"],
+          },
+        },
+        statusText: "Bad Request",
+        headers: {},
+        config: {} as any,
+      };
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toContain("Validation error");
+      expect(result.fieldErrors.email).toBe("Invalid email format");
+      expect(result.fieldErrors.full_name).toContain("Name is too short");
+    });
+
+    it("should parse 400 errors with message only", () => {
+      const error = new Error("Bad Request") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 400,
+        data: {
+          message: "Custom validation error message",
+        },
+        statusText: "Bad Request",
+        headers: {},
+        config: {} as any,
+      };
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toBe("Custom validation error message");
+    });
+
+    it("should handle 401 unauthorized errors", () => {
+      const error = new Error("Unauthorized") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 401,
+        data: {},
+        statusText: "Unauthorized",
+        headers: {},
+        config: {} as any,
+      };
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toContain("Authentication required");
+    });
+
+    it("should handle 422 unprocessable entity errors", () => {
+      const error = new Error("Unprocessable Entity") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 422,
+        data: {
+          errors: {
+            phone: "invalid_phone",
+          },
+        },
+        statusText: "Unprocessable Entity",
+        headers: {},
+        config: {} as any,
+      };
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toContain("Validation error");
+      expect(result.fieldErrors.phone).toContain("phone number");
+    });
+
+    it("should handle 429 rate limit errors", () => {
+      const error = new Error("Too Many Requests") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 429,
+        data: {},
+        statusText: "Too Many Requests",
+        headers: {},
+        config: {} as any,
+      };
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toContain("Too many requests");
+    });
+
+    it("should handle 500 server errors", () => {
+      const error = new Error("Internal Server Error") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 500,
+        data: {},
+        statusText: "Internal Server Error",
+        headers: {},
+        config: {} as any,
+      };
+
+      const result = parseApiError(error);
+      expect(result.generalMessage).toContain("Server error");
+    });
+  });
+
+  describe("handleApiError", () => {
+    it("should call setError for each field error", () => {
+      const mockSetError = jest.fn();
+      const mockShowToast = jest.fn();
+
+      const error = new Error("Bad Request") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 400,
+        data: {
+          errors: {
+            email: "Invalid email",
+            phone: "Invalid phone",
+          },
+        },
+        statusText: "Bad Request",
+        headers: {},
+        config: {} as any,
+      };
+
+      handleApiError(error, mockSetError, mockShowToast, ["email", "phone"]);
+
+      expect(mockSetError).toHaveBeenCalledTimes(2);
+      expect(mockSetError).toHaveBeenCalledWith("email", {
+        type: "server",
+        message: "Invalid email",
+      });
+      expect(mockSetError).toHaveBeenCalledWith("phone", {
+        type: "server",
+        message: "Invalid phone",
+      });
+      expect(mockShowToast).toHaveBeenCalledWith(
+        "Please correct the errors in the highlighted fields."
+      );
+    });
+
+    it("should only set errors for fields in formFields list", () => {
+      const mockSetError = jest.fn();
+      const mockShowToast = jest.fn();
+
+      const error = new Error("Bad Request") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 400,
+        data: {
+          errors: {
+            email: "Invalid email",
+            unknown_field: "Unknown error",
+          },
+        },
+        statusText: "Bad Request",
+        headers: {},
+        config: {} as any,
+      };
+
+      handleApiError(error, mockSetError, mockShowToast, ["email"]);
+
+      expect(mockSetError).toHaveBeenCalledTimes(1);
+      expect(mockSetError).toHaveBeenCalledWith("email", {
+        type: "server",
+        message: "Invalid email",
+      });
+    });
+
+    it("should show general message when no field errors", () => {
+      const mockSetError = jest.fn();
+      const mockShowToast = jest.fn();
+
+      const error = new Error("Internal Server Error") as AxiosError;
+      error.isAxiosError = true;
+      (error as AxiosError).response = {
+        status: 500,
+        data: {},
+        statusText: "Internal Server Error",
+        headers: {},
+        config: {} as any,
+      };
+
+      handleApiError(error, mockSetError, mockShowToast, ["email"]);
+
+      expect(mockSetError).not.toHaveBeenCalled();
+      expect(mockShowToast).toHaveBeenCalledWith(expect.stringContaining("Server error"));
+    });
+  });
+});