feat: IConfiguration for system and other configurations

Engine.Core/Config/BasicConfiguration.cs

@@ -0,0 +1,50 @@
+using System.Collections.Generic;
+
+namespace Engine.Core.Config;
+
+public class BasicConfiguration : IConfiguration
+{
+    public Event<IConfiguration, IConfiguration.ConfigUpdateArguments> OnAdded { get; } = new();
+    public Event<IConfiguration, IConfiguration.ConfigUpdateArguments> OnSet { get; } = new();
+    public Event<IConfiguration, IConfiguration.ConfigUpdateArguments> OnRemoved { get; } = new();
+
+    private readonly Dictionary<string, object?> values = [];
+
+    public IReadOnlyDictionary<string, object?> Values => values;
+
+    public T? Get<T>(string key, T? defaultValue = default)
+    {
+        if (!values.TryGetValue(key, out object? value))
+            return defaultValue;
+
+        if (value is T castedObject)
+            return castedObject;
+
+        try { return (T?)System.Convert.ChangeType(value, typeof(T)); } catch { }
+
+        return defaultValue;
+    }
+
+    public object? Get(string key)
+    {
+        values.TryGetValue(key, out object? value);
+        return value;
+    }
+
+    public bool Has(string key) => values.ContainsKey(key);
+
+    public void Remove<T>(string key)
+    {
+        if (values.Remove(key))
+            OnRemoved.Invoke(this, new(key));
+    }
+
+    public void Set<T>(string key, T value)
+    {
+        if (!values.TryAdd(key, value))
+            values[key] = value;
+        else
+            OnAdded.Invoke(this, new(key));
+        OnSet.Invoke(this, new(key));
+    }
+}

Engine.Core/Config/ConfigurationExtensions.cs

@@ -0,0 +1,8 @@
+using Engine.Core.Exceptions;
+
+namespace Engine.Core.Config;
+
+public static class ConfigurationExtensions
+{
+    public static T GetRequired<T>(this IConfiguration configuration, string key) => configuration.Get<T>(key) ?? throw new NotFoundException($"Type of {typeof(T).FullName} with the key {key} was not present in the {configuration.GetType().FullName}");
+}

Engine.Core/Config/IConfiguration.cs

@@ -0,0 +1,23 @@
+using System.Collections.Generic;
+
+namespace Engine.Core.Config;
+
+public interface IConfiguration
+{
+    static IConfiguration System { get; set; } = new SystemConfiguration();
+    static IConfiguration Shared { get; set; } = new BasicConfiguration();
+
+    Event<IConfiguration, ConfigUpdateArguments> OnAdded { get; }
+    Event<IConfiguration, ConfigUpdateArguments> OnSet { get; }
+    Event<IConfiguration, ConfigUpdateArguments> OnRemoved { get; }
+
+    IReadOnlyDictionary<string, object?> Values { get; }
+
+    bool Has(string key);
+    object? Get(string key);
+    T? Get<T>(string key, T? defaultValue = default);
+    void Set<T>(string key, T value);
+    void Remove<T>(string key);
+
+    readonly record struct ConfigUpdateArguments(string Key);
+}

Engine.Core/Config/SystemConfiguration.cs

@@ -0,0 +1,11 @@
+namespace Engine.Core.Config;
+
+public class SystemConfiguration : BasicConfiguration, IConfiguration
+{
+    public SystemConfiguration()
+    {
+        foreach (System.Collections.DictionaryEntry entry in System.Environment.GetEnvironmentVariables())
+            if (entry is { Key: string key, Value: not null })
+                Set(key, entry.Value);
+    }
+}