From 8e96e7b81b5dd44b71029b0fd326746479c14c59 Mon Sep 17 00:00:00 2001
From: Kirill Polishchuk <kirpolis@gmail.com>
Date: Tue, 1 Jul 2025 16:43:56 +1200
Subject: [PATCH] Added new methods

---
 README.md                                     | 29 +++++++
 .../PasswordGeneratorTests.cs                 | 85 +++++++++++++++++++
 src/KPasswordGenerator/PasswordGenerator.cs   | 26 ++++++
 3 files changed, 140 insertions(+)

diff --git a/README.md b/README.md
index ad18632..d8d9547 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,35 @@ string password = generator.Generate(16);
 Console.WriteLine(password);  // Example output: kAj79uV@E?m7_8eS
 ```
 
+## Additional Methods
+
+### `GenerateRandomLength(int minPasswordLength, int maxPasswordLength)`
+
+Generates a password of **random length within a specified range**.
+
+- Ensures the generated password meets all defined character requirements.
+- Uses secure randomness to choose the length.
+
+**Example:**
+```csharp
+string password = generator.GenerateRandomLength(12, 20);
+```
+
+---
+
+### `Validate(string password)`
+
+Validates whether a password meets the current `PasswordSettings` policy.
+
+- Checks overall length.
+- Verifies that the required number of characters from each character pool are present.
+- Returns `true` if all rules pass, otherwise `false`.
+
+- **Example:**
+```csharp
+bool isValid = generator.Validate("abcD123!");
+```
+
 ## Installation
 
 Install via NuGet:
diff --git a/src/KPasswordGenerator.Tests/PasswordGeneratorTests.cs b/src/KPasswordGenerator.Tests/PasswordGeneratorTests.cs
index d171147..f15a33a 100644
--- a/src/KPasswordGenerator.Tests/PasswordGeneratorTests.cs
+++ b/src/KPasswordGenerator.Tests/PasswordGeneratorTests.cs
@@ -60,4 +60,89 @@ public void Generate_DoesNotReturnSamePasswordEveryTime()
 
         Assert.NotEqual(password1, password2); // May rarely fail on pure randomness
     }
+
+    [Theory]
+    [InlineData(6, 12)]
+    [InlineData(10, 10)] // exact length
+    [InlineData(4, 5)]
+    public void GenerateRandomLength_ReturnsPasswordWithinRange(int min, int max)
+    {
+        var generator = CreateDefaultGenerator();
+
+        string password = generator.GenerateRandomLength(min, max);
+
+        Assert.InRange(password.Length, min, max);
+    }
+
+    [Fact]
+    public void GenerateRandomLength_Throws_WhenMinGreaterThanMax()
+    {
+        var generator = CreateDefaultGenerator(); ;
+
+        Assert.Throws<ArgumentOutOfRangeException>(() =>
+            generator.GenerateRandomLength(10, 5));
+    }
+
+    [Fact]
+    public void GenerateRandomLength_Throws_WhenMinLessThanRequired()
+    {
+        var generator = CreateDefaultGenerator();
+        int tooSmall = 3;
+
+        Assert.Throws<ArgumentOutOfRangeException>(() =>
+            generator.GenerateRandomLength(tooSmall, 10));
+    }
+
+    [Fact]
+    public void Validate_ReturnsTrue_WhenPasswordMeetsAllRequirements()
+    {
+        var generator = CreateDefaultGenerator();
+
+        // 'a', 'b' (from "abc"), '1' (from "123"), '!' (from "!@#")
+        string validPassword = "ab1!xyz";
+
+        Assert.True(generator.Validate(validPassword));
+    }
+
+    [Fact]
+    public void Validate_ReturnsFalse_WhenPasswordTooShort()
+    {
+        var generator = CreateDefaultGenerator();
+
+        string shortPassword = "a1!";
+
+        Assert.False(generator.Validate(shortPassword));
+    }
+
+    [Fact]
+    public void Validate_ReturnsFalse_WhenRequirementNotMet()
+    {
+        var generator = CreateDefaultGenerator();
+
+        // Missing digits
+        string invalidPassword = "ab!!xyz";
+
+        Assert.False(generator.Validate(invalidPassword));
+    }
+
+    [Fact]
+    public void Validate_Throws_WhenPasswordIsNull()
+    {
+        var generator = CreateDefaultGenerator();
+
+        Assert.Throws<ArgumentNullException>(() =>
+            generator.Validate(null!));
+    }
+
+    private static PasswordGenerator CreateDefaultGenerator()
+    {
+        List<CharacterRequirement> requirements = 
+        [
+            new CharacterRequirement(2, "abc"),
+            new CharacterRequirement(1, "123"),
+            new CharacterRequirement(1, "!@#")
+        ];
+
+        return new PasswordGenerator(new PasswordSettings(requirements));
+    }
 }
\ No newline at end of file
diff --git a/src/KPasswordGenerator/PasswordGenerator.cs b/src/KPasswordGenerator/PasswordGenerator.cs
index 05be9ad..0feb73c 100644
--- a/src/KPasswordGenerator/PasswordGenerator.cs
+++ b/src/KPasswordGenerator/PasswordGenerator.cs
@@ -34,4 +34,30 @@ public string Generate(int passwordLength)
 
         return buffer.ToString();
     }
+
+    public string GenerateRandomLength(int minPasswordLength, int maxPasswordLength)
+    {
+        ArgumentOutOfRangeException.ThrowIfGreaterThan(minPasswordLength, maxPasswordLength);
+        ArgumentOutOfRangeException.ThrowIfLessThan(minPasswordLength, _passwordSettings.MinimumPasswordLength);
+
+        int length = RandomNumberGenerator.GetInt32(minPasswordLength, maxPasswordLength + 1);
+
+        return Generate(length);
+    }
+
+    public bool Validate(string password)
+    {
+        ArgumentNullException.ThrowIfNull(password);
+
+        if (password.Length < _passwordSettings.MinimumPasswordLength) return false;
+
+        foreach (var requirement in _passwordSettings.CharacterRequirements)
+        {
+            int count = password.Count(requirement.CharacterPool.Contains);
+
+            if (count < requirement.MinRequired) return false;
+        }
+
+        return true;
+    }
 }
\ No newline at end of file