add method for blending colors

Author: mikhailChelbaev

Sources/ComponentsKit/Shared/Colors/UniversalColor.swift

@@ -86,6 +86,47 @@ public struct UniversalColor: Hashable {
         return UIColor(color)
       }
     }
+
+    /// Returns a tuple containing the red, green, blue, and alpha components of the color.
+    private var rgba: (r: CGFloat, g: CGFloat, b: CGFloat, a: CGFloat) {
+      switch self {
+      case let .rgba(r, g, b, a):
+        return (r, g, b, a)
+      case .uiColor, .color:
+        var red: CGFloat = 0
+        var green: CGFloat = 0
+        var blue: CGFloat = 0
+        var alpha: CGFloat = 0
+
+        self.uiColor.getRed(&red, green: &green, blue: &blue, alpha: &alpha)
+
+        return (red, green, blue, alpha)
+      }
+    }
+
+    /// Returns a new `ColorRepresentable` by blending the current color with another color.
+    ///
+    /// The blending is performed using the alpha value of the current color,
+    /// where the second color is treated as fully opaque (alpha = `1.0 - self.alpha`).
+    ///
+    /// The resulting color's RGBA components are calculated as:
+    /// - `red = self.red * self.alpha + other.red * (1.0 - self.alpha)`
+    /// - `green = self.green * self.alpha + other.green * (1.0 - self.alpha)`
+    /// - `blue = self.blue * self.alpha + other.blue * (1.0 - self.alpha)`
+    /// - The resulting color's alpha will always be `1.0`.
+    ///
+    /// - Parameter other: The `ColorRepresentable` to blend with the current color.
+    /// - Returns: A new `ColorRepresentable` instance representing the blended color.
+    fileprivate func blended(with other: Self) -> Self {
+      let rgba = self.rgba
+      let otherRgba = other.rgba
+
+      let red = rgba.r * rgba.a + otherRgba.r * (1.0 - rgba.a)
+      let green = rgba.g * rgba.a + otherRgba.g * (1.0 - rgba.a)
+      let blue = rgba.b * rgba.a + otherRgba.b * (1.0 - rgba.a)
+
+      return .rgba(r: red, g: green, b: blue, a: 1.0)
+    }
   }
 
   // MARK: - Properties
@@ -119,29 +160,6 @@ public struct UniversalColor: Hashable {
     return Self(light: universal, dark: universal)
   }
 
-  // MARK: - Methods
-
-  /// Returns a new `UniversalColor` with the specified opacity.
-  ///
-  /// - Parameter alpha: The desired opacity (0.0–1.0).
-  /// - Returns: A new `UniversalColor` instance with the adjusted opacity.
-  public func withOpacity(_ alpha: CGFloat) -> Self {
-    return .init(
-      light: self.light.withOpacity(alpha),
-      dark: self.dark.withOpacity(alpha)
-    )
-  }
-
-  /// Returns a disabled version of the color based on a global opacity configuration.
-  ///
-  /// - Parameter isEnabled: A Boolean value indicating whether the color should be enabled.
-  /// - Returns: A new `UniversalColor` instance with reduced opacity if `isEnabled` is `false`.
-  public func enabled(_ isEnabled: Bool) -> Self {
-    return isEnabled
-    ? self
-    : self.withOpacity(ComponentsKitConfig.shared.layout.disabledOpacity)
-  }
-
   // MARK: - Colors
 
   /// Returns the `UIColor` representation of the color.
@@ -167,4 +185,47 @@ public struct UniversalColor: Hashable {
   public var cgColor: CGColor {
     return self.uiColor.cgColor
   }
+
+  // MARK: - Methods
+
+  /// Returns a new `UniversalColor` with the specified opacity.
+  ///
+  /// - Parameter alpha: The desired opacity (0.0–1.0).
+  /// - Returns: A new `UniversalColor` instance with the adjusted opacity.
+  public func withOpacity(_ alpha: CGFloat) -> Self {
+    return .init(
+      light: self.light.withOpacity(alpha),
+      dark: self.dark.withOpacity(alpha)
+    )
+  }
+
+  /// Returns a disabled version of the color based on a global opacity configuration.
+  ///
+  /// - Parameter isEnabled: A Boolean value indicating whether the color should be enabled.
+  /// - Returns: A new `UniversalColor` instance with reduced opacity if `isEnabled` is `false`.
+  public func enabled(_ isEnabled: Bool) -> Self {
+    return isEnabled
+    ? self
+    : self.withOpacity(ComponentsKitConfig.shared.layout.disabledOpacity)
+  }
+
+  /// Returns a new `UniversalColor` by blending the current color with another color.
+  ///
+  /// The blending is performed using the alpha value of the current color,
+  /// where the second color is treated as fully opaque (alpha = `1.0 - self.alpha`).
+  ///
+  /// The resulting color's RGBA components are calculated as:
+  /// - `red = self.red * self.alpha + other.red * (1.0 - self.alpha)`
+  /// - `green = self.green * self.alpha + other.green * (1.0 - self.alpha)`
+  /// - `blue = self.blue * self.alpha + other.blue * (1.0 - self.alpha)`
+  /// - The resulting color's alpha will always be `1.0`.
+  ///
+  /// - Parameter other: The `UniversalColor` to blend with the current color.
+  /// - Returns: A new `UniversalColor` instance representing the blended color.
+  public func blended(with other: Self) -> Self {
+    return .init(
+      light: self.light.blended(with: other.light),
+      dark: self.dark.blended(with: other.dark)
+    )
+  }
 }