Some new features that I created at apis-rework

EXILED/EXILED.sln

@@ -21,6 +21,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Exiled.CreditTags", "Exiled
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Exiled.CustomRoles", "Exiled.CustomRoles\Exiled.CustomRoles.csproj", "{417C3309-8B93-4218-A1D1-D4BB7B09BE0F}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Exiled.CustomUnits", "Exiled.CustomUnits\Exiled.CustomUnits.csproj", "{9C4931B5-FB58-4069-815D-02C9FD8BEC05}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -74,6 +76,12 @@ Global
 		{417C3309-8B93-4218-A1D1-D4BB7B09BE0F}.Installer|Any CPU.ActiveCfg = Installer|Any CPU
 		{417C3309-8B93-4218-A1D1-D4BB7B09BE0F}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{417C3309-8B93-4218-A1D1-D4BB7B09BE0F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{9C4931B5-FB58-4069-815D-02C9FD8BEC05}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{9C4931B5-FB58-4069-815D-02C9FD8BEC05}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{9C4931B5-FB58-4069-815D-02C9FD8BEC05}.Installer|Any CPU.ActiveCfg = Debug|Any CPU
+		{9C4931B5-FB58-4069-815D-02C9FD8BEC05}.Installer|Any CPU.Build.0 = Debug|Any CPU
+		{9C4931B5-FB58-4069-815D-02C9FD8BEC05}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{9C4931B5-FB58-4069-815D-02C9FD8BEC05}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

EXILED/Exiled.API/Extensions/StringExtensions.cs

@@ -14,6 +14,7 @@ namespace Exiled.API.Extensions
     using System.Text;
     using System.Text.RegularExpressions;
 
+    using Exiled.API.Features;
     using Exiled.API.Features.Pools;
 
     /// <summary>
@@ -74,6 +75,21 @@ public static (string commandName, string[] arguments) ExtractCommand(this strin
             return (extractedArguments[0].ToLower(), extractedArguments.Skip(1).ToArray());
         }
 
+        /// <summary>
+        /// Parse players from a <see cref="string"/>.
+        /// </summary>
+        /// <param name="query">Query to be parsed.</param>
+        /// <param name="separator">Separator to be used in the query.</param>
+        /// <returns>An <see cref="IEnumerable{T}"/> of <see cref="Player"/> if any found, otherwise an empty <see cref="IEnumerable{T}"/>.</returns>
+        public static IEnumerable<Player> ParsePlayers(this string query, char separator = '.')
+        {
+            foreach (string str in query.Split(separator))
+            {
+                if (Player.TryGet(str, out Player player))
+                    yield return player;
+            }
+        }
+
         /// <summary>
         /// Converts a <see cref="string"/> to snake_case convention.
         /// </summary>

EXILED/Exiled.API/Features/Attributes/Config/CustomValidatorAttribute.cs

@@ -0,0 +1,39 @@
+// -----------------------------------------------------------------------
+// <copyright file="CustomValidatorAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes.Config
+{
+    using System;
+
+    /// <summary>
+    /// A custom validator for config values and base class for all config validators.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Property, AllowMultiple = true)]
+    public class CustomValidatorAttribute : Attribute
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="CustomValidatorAttribute"/> class.
+        /// </summary>
+        /// <param name="validator"><inheritdoc cref="Validator"/></param>
+        public CustomValidatorAttribute(Func<object, bool> validator)
+        {
+            Validator = validator;
+        }
+
+        /// <summary>
+        /// Gets a function that validates an object.
+        /// </summary>
+        public Func<object, bool> Validator { get; }
+
+        /// <summary>
+        /// Validates an object.
+        /// </summary>
+        /// <param name="obj">Object to validate.</param>
+        /// <returns><c>true</c> if validation was successful, <c>false</c> otherwise.</returns>
+        public bool Validate(object obj) => Validator(obj);
+    }
+}

EXILED/Exiled.API/Features/Attributes/Config/MaxLengthAttribute.cs

@@ -0,0 +1,28 @@
+// -----------------------------------------------------------------------
+// <copyright file="MaxLengthAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes.Config
+{
+    using System.Collections;
+    using System.Linq;
+
+    /// <summary>
+    /// An attribute that checks if length of a sequence is less than a specified value.
+    /// </summary>
+    public class MaxLengthAttribute : CustomValidatorAttribute
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MaxLengthAttribute"/> class.
+        /// </summary>
+        /// <param name="length">Maximum length of sequence.</param>
+        /// <param name="inclusive">Whether check is inclusive or not.</param>
+        public MaxLengthAttribute(int length, bool inclusive = false)
+            : base(x => x is IEnumerable enumerable && enumerable.Cast<object>().Count() < (inclusive ? length + 1 : length))
+        {
+        }
+    }
+}

EXILED/Exiled.API/Features/Attributes/Config/MaxValueAttribute.cs

@@ -0,0 +1,27 @@
+// -----------------------------------------------------------------------
+// <copyright file="MaxValueAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes.Config
+{
+    using System.Collections;
+
+    /// <summary>
+    /// An attribute to check if a value is less than a specified value.
+    /// </summary>
+    public class MaxValueAttribute : CustomValidatorAttribute
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MaxValueAttribute"/> class.
+        /// </summary>
+        /// <param name="maxValue">Maximum value.</param>
+        /// <param name="inclusive">Whether check should be inclusive or not.</param>
+        public MaxValueAttribute(object maxValue, bool inclusive = true)
+            : base(x => Comparer.Default.Compare(maxValue, x) > (inclusive ? -1 : 0))
+        {
+        }
+    }
+}

EXILED/Exiled.API/Features/Attributes/Config/MinLengthAttribute.cs

@@ -0,0 +1,28 @@
+// -----------------------------------------------------------------------
+// <copyright file="MinLengthAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes.Config
+{
+    using System.Collections;
+    using System.Linq;
+
+    /// <summary>
+    /// An attribute that checks if length of a sequence is greater than a specified value.
+    /// </summary>
+    public class MinLengthAttribute : CustomValidatorAttribute
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MinLengthAttribute"/> class.
+        /// </summary>
+        /// <param name="length">Maximum length of sequence.</param>
+        /// <param name="inclusive">Whether check is inclusive or not.</param>
+        public MinLengthAttribute(int length, bool inclusive = false)
+            : base(x => x is IEnumerable enumerable && enumerable.Cast<object>().Count() > (inclusive ? length - 1 : length))
+        {
+        }
+    }
+}

EXILED/Exiled.API/Features/Attributes/Config/MinValueAttribute.cs

@@ -0,0 +1,27 @@
+// -----------------------------------------------------------------------
+// <copyright file="MinValueAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes.Config
+{
+    using System.Collections;
+
+    /// <summary>
+    /// An attribute to check if value is greater than or equal to min value.
+    /// </summary>
+    public class MinValueAttribute : CustomValidatorAttribute
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MinValueAttribute"/> class.
+        /// </summary>
+        /// <param name="minValue">Minimum value.</param>
+        /// <param name="inclusive">Whether check should be inclusive or not.</param>
+        public MinValueAttribute(object minValue, bool inclusive = true)
+            : base(x => Comparer.Default.Compare(x, minValue) > (inclusive ? -1 : 0))
+        {
+        }
+    }
+}

EXILED/Exiled.API/Features/Attributes/Config/OneOfAttribute.cs

@@ -0,0 +1,26 @@
+// -----------------------------------------------------------------------
+// <copyright file="OneOfAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes.Config
+{
+    using System;
+
+    /// <summary>
+    /// An attribute to check if a value is one of a possible values.
+    /// </summary>
+    public class OneOfAttribute : CustomValidatorAttribute
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="OneOfAttribute"/> class.
+        /// </summary>
+        /// <param name="values">Values.</param>
+        public OneOfAttribute(params object[] values)
+            : base(x => Array.IndexOf(values, x) != -1)
+        {
+        }
+    }
+}

EXILED/Exiled.API/Features/Attributes/CustomTeamAttribute.cs

@@ -0,0 +1,19 @@
+// -----------------------------------------------------------------------
+// <copyright file="CustomTeamAttribute.cs" company="Exiled Team">
+// Copyright (c) Exiled Team. All rights reserved.
+// Licensed under the CC BY-SA 3.0 license.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Exiled.API.Features.Attributes
+{
+    using System;
+
+    /// <summary>
+    /// An attribute to easily manage custom teams initialization.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Class)]
+    public sealed class CustomTeamAttribute : Attribute
+    {
+    }
+}