PasswordGeneratorService

PWManager.Application/DependencyInjection.cs

@@ -0,0 +1,16 @@
+using Microsoft.Extensions.DependencyInjection;
+using PWManager.Application.Services;
+using PWManager.Domain.Services.Interfaces;
+
+namespace PWManager.Application; 
+
+public static class DependencyInjection {
+
+    public static IServiceCollection AddApplicationServices(this IServiceCollection services) {
+
+        services.AddTransient<IPasswordGeneratorService, PasswordGeneratorService>();
+
+        return services;
+    }
+
+}

PWManager.Application/Interfaces/IUserSettings.cs

@@ -0,0 +1,10 @@
+using PWManager.Domain.ValueObjects;
+
+namespace PWManager.Application.Interfaces; 
+
+public interface IUserSettings {
+
+    public PasswordGeneratorCriteria GetPasswordGeneratorCriteria();
+    public ClipboardTimeoutSetting GetClipboardTimeoutSetting();
+    public MainGroupSetting GetMainGroupSetting();
+}

PWManager.Application/PWManager.Application.csproj

@@ -10,4 +10,8 @@
       <ProjectReference Include="..\PWManager.Domain\PWManager.Domain.csproj" />
     </ItemGroup>
 
+    <ItemGroup>
+      <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="7.0.0" />
+    </ItemGroup>
+
 </Project>

PWManager.Application/Services/PasswordGeneratorService.cs

@@ -0,0 +1,60 @@
+using System.Text;
+using PWManager.Application.Interfaces;
+using PWManager.Domain.Exceptions;
+using PWManager.Domain.Services.Interfaces;
+using PWManager.Domain.ValueObjects;
+
+namespace PWManager.Application.Services; 
+
+public class PasswordGeneratorService : IPasswordGeneratorService {
+
+    private readonly IUserSettings _userSettings;
+
+    private const string Lowercase = "abcdefghijklmnopqrstuvwxyz";
+    private const string Uppercase = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    private const string SpecialChars = "!#$%&*+,-.:;<=>?^_~";
+    private const string Numeric = "0123456789";
+    private const char Space = ' ';
+    private const string Brackets = "()[]{}";
+
+    private readonly Random _rng;
+
+    public PasswordGeneratorService(IUserSettings userSettings) : this(userSettings, new Random()) {
+    }
+
+    public PasswordGeneratorService(IUserSettings userSettings, Random rng) {
+        _userSettings = userSettings;
+        _rng = rng;
+    }
+
+    public string GeneratePasswordWith(PasswordGeneratorCriteria criteria) {
+        var possibleChars = BuildPossibleChars(criteria);
+        if (possibleChars.Length <= 0) {
+            throw new PasswordGenerationException("Possible Password character set is empty!");
+        }
+
+        var password = new StringBuilder();
+        var passwordLength = _rng.Next(criteria.MinLength, criteria.MaxLength + 1);
+        for (int i = 0; i < passwordLength; ++i) {
+            var randomCharIndex = _rng.Next(possibleChars.Length);
+            password.Append(possibleChars[randomCharIndex]);
+        }
+
+        return password.ToString();
+    }
+
+    public string GeneratePassword() {
+        return GeneratePasswordWith(_userSettings.GetPasswordGeneratorCriteria());
+    }
+
+    private static char[] BuildPossibleChars(PasswordGeneratorCriteria criteria) {
+        var allPossibleChars = new StringBuilder();
+        if (criteria.IncludeUpperCase) allPossibleChars.Append(Uppercase);
+        if (criteria.IncludeBrackets) allPossibleChars.Append(Brackets);
+        if (criteria.IncludeNumeric) allPossibleChars.Append(Numeric);
+        if (criteria.IncludeSpaces) allPossibleChars.Append(Space);
+        if (criteria.IncludeSpecial) allPossibleChars.Append(SpecialChars);
+        if (criteria.IncludeLowerCase) allPossibleChars.Append(Lowercase);
+        return allPossibleChars.ToString().ToCharArray();
+    }
+}

PWManager.Domain/Exceptions/PasswordGenerationException.cs

@@ -0,0 +1,10 @@
+using System.Runtime.Serialization;
+
+namespace PWManager.Domain.Exceptions; 
+
+public class PasswordGenerationException : Exception {
+    public PasswordGenerationException() { }
+    protected PasswordGenerationException(SerializationInfo info, StreamingContext context) : base(info, context) { }
+    public PasswordGenerationException(string? message) : base(message) { }
+    public PasswordGenerationException(string? message, Exception? innerException) : base(message, innerException) { }
+}

PWManager.Domain/ValueObjects/PasswordGeneratorCriteria.cs

@@ -10,19 +10,30 @@ public class PasswordGeneratorCriteria : ValueObject {
         public bool IncludeSpecial { get; }
         public bool IncludeSpaces { get; }
         public bool IncludeBrackets { get; }
-        public uint MinLength { get; }
-        public uint MaxLength { get; }
+        public int MinLength { get; }
+        public int MaxLength { get; }
 
-        public PasswordGeneratorCriteria(bool includeLowerCase, bool includeUppercase, bool includeNumeric, bool includeSpecial, bool includeBrackets, bool includeSpaces, uint minLength, uint maxLength)
-        {
+        public PasswordGeneratorCriteria(bool includeLowerCase, bool includeUpperCase, bool includeNumeric, bool includeSpecial, bool includeBrackets, bool includeSpaces, int minLength, int maxLength) {
+            if (minLength <= 0) {
+                throw new ArgumentException("MinLength cannot be less than or equal to 0");
+            }
+
+            if (maxLength < minLength) {
+                throw new ArgumentException("MaxLength cannot be less than MinLength");
+            }
+
             IncludeLowerCase = includeLowerCase;
-            IncludeUpperCase = includeUppercase;
+            IncludeUpperCase = includeUpperCase;
             IncludeNumeric = includeNumeric;
             IncludeSpecial = includeSpecial;
             IncludeBrackets = includeBrackets;
             IncludeSpaces = includeSpaces;
             MinLength = minLength;
             MaxLength = maxLength;
+
+            if (NoCharactersIncluded()) {
+                throw new ArgumentException("Password Generator must have some characters enabled!");
+            }
         }
 
         protected override IEnumerable<object> GetEqualityComponents() {
@@ -35,5 +46,9 @@ protected override IEnumerable<object> GetEqualityComponents() {
             yield return MinLength;
             yield return MaxLength;
         }
+
+        private bool NoCharactersIncluded() {
+            return !IncludeLowerCase && !IncludeUpperCase && !IncludeNumeric && !IncludeSpecial && !IncludeBrackets;
+        }
     }
 }

PWManager.UnitTests/Domain/ValueObjects/PasswordCriteriaTests.cs

@@ -0,0 +1,47 @@
+using System.Reflection;
+using PWManager.Domain.ValueObjects;
+
+namespace PWManager.UnitTests.Domain.ValueObjects; 
+
+public class PasswordCriteriaTests {
+
+    [Theory]
+    [InlineData(0)]
+    [InlineData(-1)]
+    public void Criteria_ShouldNot_AcceptInvalidMinLength(int minLength) {
+        var exception = Assert.Throws<ArgumentException>(() => {
+            var criteria = new PasswordGeneratorCriteria(true, true, true, true, true, true, minLength, 10);
+        });
+
+        Assert.Equal("MinLength cannot be less than or equal to 0", exception.Message);
+    }
+
+    [Fact]
+    public void Criteria_ShouldNot_AcceptInvalidMaxLength() {
+        var exception = Assert.Throws<ArgumentException>(() => {
+            var criteria = new PasswordGeneratorCriteria(true, true, true, true, true, true, 10, 5);
+        });
+
+        Assert.Equal("MaxLength cannot be less than MinLength", exception.Message);
+    }
+
+    [Fact]
+    public void Criteria_Should_AcceptEqualMinMaxLength() {
+        try {
+            var criteria = new PasswordGeneratorCriteria(true, true, true, true, true, true, 5, 5);
+        }
+        catch (Exception ex) {
+            Assert.Fail("Exception was thrown when Min and MaxLength were equal " + ex.Message);
+        }
+    }
+
+    [Fact]
+    public void Criteria_ShouldNot_AcceptNoIncludeSelected() {
+        var exception = Assert.Throws<ArgumentException>(() => {
+            var criteria = new PasswordGeneratorCriteria(false,false,false,false,false,false,5,5);
+        });
+
+        Assert.Equal("Password Generator must have some characters enabled!", exception.Message);
+
+    }
+}