Player preliminary work

Source/AppScaffolding/Ensure.cs

@@ -0,0 +1,97 @@
+using System;
+
+namespace AppScaffolding;
+
+/// <summary>
+/// A helper class for ensuring parameter conditions.
+/// Yoinked from https://github.com/CoryCharlton/CCSWE.Core/blob/master/src/Core/Ensure.cs
+/// </summary>
+public static class Ensure
+{
+    private static Exception GetException<TException>(string name, string message) where TException : Exception, new()
+    {
+        Exception exception = (TException)Activator.CreateInstance(typeof(TException), message);
+
+        if (exception is ArgumentNullException)
+        {
+            return new ArgumentNullException(name, message);
+        }
+
+        if (exception is ArgumentOutOfRangeException)
+        {
+            return new ArgumentOutOfRangeException(name, message);
+        }
+
+        if (exception is ArgumentException)
+        {
+            return new ArgumentException(message, name);
+        }
+
+        return exception;
+    }
+
+    /// <summary>
+    /// Throws an <see cref="ArgumentOutOfRangeException"/> if the expression evaluates to <c>false</c>.
+    /// </summary>
+    /// <param name="name">The name of the parameter we are validating.</param>
+    /// <param name="expression">The expression that will be evaluated.</param>
+    /// <param name="message">The message associated with the <see cref="Exception"/></param>
+    /// <exception cref="ArgumentOutOfRangeException">Thrown when the expression evaluates to <c>false</c></exception>.
+    public static void IsInRange(string name, bool expression, string message = null)
+    {
+        IsValid<ArgumentOutOfRangeException>(name, expression, string.IsNullOrWhiteSpace(message) ? $"The value passed for '{name}' is out of range." : message);
+    }
+
+    /// <summary>
+    /// Throws an <see cref="ArgumentNullException"/> if the value is <c>null</c>.
+    /// </summary>
+    /// <param name="name">The name of the parameter we are validating.</param>
+    /// <param name="value">The value that will be evaluated.</param>
+    /// <param name="message">The message associated with the <see cref="Exception"/></param>
+    /// <exception cref="ArgumentNullException">Thrown when the value is <c>null</c></exception>.
+    public static void IsNotNull<T>(string name, T value, string message = null)
+    {
+        IsValid<ArgumentNullException>(name, value != null, string.IsNullOrWhiteSpace(message) ? $"The value passed for '{name}' is null." : message);
+    }
+
+    /// <summary>
+    /// Throws an <see cref="ArgumentException"/> if the value is <c>null</c> or <c>whitespace</c>.
+    /// </summary>
+    /// <param name="name">The name of the parameter we are validating.</param>
+    /// <param name="value">The value that will be evaluated.</param>
+    /// <param name="message">The message associated with the <see cref="Exception"/></param>
+    /// <exception cref="ArgumentException">Thrown when the value is <c>null</c> or <c>whitespace</c>.</exception>.
+    public static void IsNotNullOrWhitespace(string name, string value, string message = null)
+    {
+        IsValid<ArgumentException>(name, !string.IsNullOrWhiteSpace(value), string.IsNullOrWhiteSpace(message) ? $"The value passed for '{name}' is empty, null, or whitespace." : message);
+    }
+
+    /// <summary>
+    /// Throws an <see cref="ArgumentException"/> if the expression evaluates to <c>false</c>.
+    /// </summary>
+    /// <param name="name">The name of the parameter we are validating.</param>
+    /// <param name="expression">The expression that will be evaluated.</param>
+    /// <param name="message">The message associated with the <see cref="Exception"/></param>
+    /// <exception cref="ArgumentException">Thrown when the expression evaluates to <c>false</c></exception>.
+    public static void IsValid(string name, bool expression, string message = null)
+    {
+        IsValid<ArgumentException>(name, expression, string.IsNullOrWhiteSpace(message) ? $"The value passed for '{name}' is not valid." : message);
+    }
+
+    /// <summary>
+    /// Throws an exception if the expression evaluates to <c>false</c>.
+    /// </summary>
+    /// <typeparam name="TException">The type of <see cref="Exception"/> to throw.</typeparam>
+    /// <param name="name">The name of the parameter we are validating.</param>
+    /// <param name="expression">The expression that will be evaluated.</param>
+    /// <param name="message">The message associated with the <see cref="Exception"/></param>
+    public static void IsValid<TException>(string name, bool expression, string message = null) where TException : Exception, new()
+    {
+        if (expression)
+        {
+            return;
+        }
+
+        throw GetException<TException>(name, string.IsNullOrWhiteSpace(message) ? $"The value passed for '{name}' is not valid." : message);
+    }
+}