增加换肤功能

TUIKit/TUICallKit/TUICallKit-Swift/Utils/Observers.swift

@@ -0,0 +1,87 @@
+//
+//  Observers.swift
+//  TUICallKit
+//
+//  Created by vincepzhang on 2023/4/3.
+//
+import Foundation
+
+class Observer {}
+
+public class Observable<Type> {
+    
+    // MARK: - Callback
+    fileprivate class Callback {
+        fileprivate weak var observer: AnyObject?
+        fileprivate let options: [ObservableOptions]
+        fileprivate let closure: (Type, ObservableOptions) -> Void
+        
+        fileprivate init(
+            observer: AnyObject,
+            options: [ObservableOptions],
+            closure: @escaping (Type, ObservableOptions) -> Void) {
+                self.observer = observer
+                self.options = options
+                self.closure = closure
+            }
+    }
+    
+    // MARK: - Properties Use Swift's didSet feature to call back the value to the callback
+    public var value: Type {
+        didSet {
+            removeNilObserverCallbacks()
+            notifyCallbacks(value: oldValue, option: .old)
+            notifyCallbacks(value: value, option: .new)
+        }
+    }
+    
+    private func removeNilObserverCallbacks() {
+        callbacks = callbacks.filter { $0.observer != nil }
+    }
+    
+    // MARK: Callback to callback to implement closure callback
+    private func notifyCallbacks(value: Type, option: ObservableOptions) {
+        let callbacksToNotify = callbacks.filter { $0.options.contains(option) }
+        callbacksToNotify.forEach { $0.closure(value, option) }
+    }
+    
+    // MARK: - Object Lifecycle
+    public init(_ value: Type) {
+        self.value = value
+    }
+    
+    // MARK: - Managing Observers
+    private var callbacks: [Callback] = []
+    
+    public func addObserver(
+        _ observer: AnyObject,
+        removeIfExists: Bool = true,
+        options: [ObservableOptions] = [.new],
+        closure: @escaping (Type, ObservableOptions) -> Void) {
+            if removeIfExists {
+                removeObserver(observer)
+            }
+            let callback = Callback(observer: observer, options: options, closure: closure)
+            callbacks.append(callback)
+            if options.contains(.initial) {
+                closure(value, .initial)
+            }
+        }
+    
+    public func removeObserver(_ observer: AnyObject) {
+        callbacks = callbacks.filter { $0.observer !== observer }
+    }
+}
+
+// MARK: - ObservableOptions
+public struct ObservableOptions: OptionSet {
+    public static let initial = ObservableOptions(rawValue: 1 << 0)
+    public static let old = ObservableOptions(rawValue: 1 << 1)
+    public static let new = ObservableOptions(rawValue: 1 << 2)
+    
+    public var rawValue: Int
+    
+    public init(rawValue: Int) {
+        self.rawValue = rawValue
+    }
+}