Added basic WhatsApp implementation

test/LinkMobility.Tests/WhatsApp/Contents/TextMessageContentTest.cs

@@ -0,0 +1,40 @@
+using AMWD.Net.Api.LinkMobility.WhatsApp;
+
+namespace LinkMobility.Tests.WhatsApp.Contents
+{
+	[TestClass]
+	public class TextMessageContentTest
+	{
+		[TestMethod]
+		[DataRow(true)]
+		[DataRow(false)]
+		public void ShouldValidateSuccessful(bool previewUrl)
+		{
+			// Arrange
+			var content = new TextMessageContent("Hello, World!");
+			content.Body.PreviewUrl = previewUrl;
+
+			// Act
+			bool isValid = content.IsValid();
+
+			// Assert
+			Assert.IsTrue(isValid);
+		}
+
+		[TestMethod]
+		[DataRow(null)]
+		[DataRow("")]
+		[DataRow("   ")]
+		public void ShouldValidateNotSuccessful(string text)
+		{
+			// Arrange
+			var content = new TextMessageContent(text);
+
+			// Act
+			bool isValid = content.IsValid();
+
+			// Assert
+			Assert.IsFalse(isValid);
+		}
+	}
+}