mRemoteNG/mRemoteNGTests/Installer/InstalledWindowsUpdateCheckerTests.cs

using NUnit.Framework;
using System;
using System.Reflection;

namespace mRemoteNGTests.Installer
{
    [TestFixture]
    public class InstalledWindowsUpdateCheckerTests
    {
        private CustomActions.InstalledWindowsUpdateChecker _checker;
        private MethodInfo _sanitizeKbIdMethod;
        private MethodInfo _buildWhereClauseMethod;

        [SetUp]
        public void Setup()
        {
            _checker = new CustomActions.InstalledWindowsUpdateChecker();
            
            // Use reflection to access private methods for testing
            var type = typeof(CustomActions.InstalledWindowsUpdateChecker);
            _sanitizeKbIdMethod = type.GetMethod("SanitizeKbId", BindingFlags.NonPublic | BindingFlags.Instance);
            _buildWhereClauseMethod = type.GetMethod("BuildWhereClauseFromKbList", BindingFlags.NonPublic | BindingFlags.Instance);
        }

        #region SanitizeKbId Tests

        [Test]
        public void SanitizeKbId_ValidKbWithPrefix_ReturnsUppercased()
        {
            var result = InvokeSanitizeKbId("KB1234567");
            Assert.That(result, Is.EqualTo("KB1234567"));
        }

        [Test]
        public void SanitizeKbId_ValidKbLowercase_ReturnsUppercased()
        {
            var result = InvokeSanitizeKbId("kb1234567");
            Assert.That(result, Is.EqualTo("KB1234567"));
        }

        [Test]
        public void SanitizeKbId_ValidKbMixedCase_ReturnsUppercased()
        {
            var result = InvokeSanitizeKbId("Kb1234567");
            Assert.That(result, Is.EqualTo("KB1234567"));
        }

        [Test]
        public void SanitizeKbId_ValidNumberOnly_ReturnsWithKbPrefix()
        {
            var result = InvokeSanitizeKbId("1234567");
            Assert.That(result, Is.EqualTo("KB1234567"));
        }

        [Test]
        public void SanitizeKbId_WithWhitespace_ReturnsTrimmedAndUppercased()
        {
            var result = InvokeSanitizeKbId("  KB1234567  ");
            Assert.That(result, Is.EqualTo("KB1234567"));
        }

        [Test]
        public void SanitizeKbId_SqlInjectionAttempt_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("KB1234' OR '1'='1");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_WqlInjectionWithSemicolon_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("KB1234; DROP TABLE");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_WithSpecialCharacters_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("KB1234@#$");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_NullInput_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId(null);
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_EmptyString_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_WhitespaceOnly_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("   ");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_OnlyKbPrefix_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("KB");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_WithDashes_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("KB-1234567");
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void SanitizeKbId_WithUnderscores_ReturnsEmpty()
        {
            var result = InvokeSanitizeKbId("KB_1234567");
            Assert.That(result, Is.Empty);
        }

        #endregion

        #region BuildWhereClauseFromKbList Tests

        [Test]
        public void BuildWhereClause_SingleValidKb_ReturnsCorrectClause()
        {
            var result = InvokeBuildWhereClause(new[] { "KB1234567" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567'"));
        }

        [Test]
        public void BuildWhereClause_MultipleValidKbs_ReturnsOrClause()
        {
            var result = InvokeBuildWhereClause(new[] { "KB1234567", "KB7654321" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321'"));
        }

        [Test]
        public void BuildWhereClause_InvalidKb_SkipsInvalid()
        {
            var result = InvokeBuildWhereClause(new[] { "KB1234567", "KB1234'; DROP--", "KB7654321" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321'"));
        }

        [Test]
        public void BuildWhereClause_AllInvalidKbs_ReturnsEmpty()
        {
            var result = InvokeBuildWhereClause(new[] { "'; DROP TABLE", "OR 1=1--" });
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void BuildWhereClause_EmptyList_ReturnsEmpty()
        {
            var result = InvokeBuildWhereClause(Array.Empty<string>());
            Assert.That(result, Is.Empty);
        }

        [Test]
        public void BuildWhereClause_NullValues_SkipsNulls()
        {
            var result = InvokeBuildWhereClause(new[] { "KB1234567", null, "KB7654321" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321'"));
        }

        [Test]
        public void BuildWhereClause_MixedCaseKbs_NormalizesToUppercase()
        {
            var result = InvokeBuildWhereClause(new[] { "kb1234567", "KB7654321" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321'"));
        }

        [Test]
        public void BuildWhereClause_DigitOnlyKb_AddsKbPrefix()
        {
            var result = InvokeBuildWhereClause(new[] { "1234567" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567'"));
        }

        [Test]
        public void BuildWhereClause_MixedPrefixedAndDigitOnly_NormalizesAll()
        {
            var result = InvokeBuildWhereClause(new[] { "1234567", "KB7654321", "kb9999999" });
            Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321' OR HotFixID='KB9999999'"));
        }

        #endregion

        #region Helper Methods

        private string InvokeSanitizeKbId(string input)
        {
            return (string)_sanitizeKbIdMethod.Invoke(_checker, new object[] { input });
        }

        private string InvokeBuildWhereClause(string[] kbList)
        {
            return (string)_buildWhereClauseMethod.Invoke(_checker, new object[] { kbList });
        }

        #endregion
    }
}