الأنماط المركبة (Compound Patterns — MVC)

// Model — Observable
class Model {
  constructor() {
    this.data = {};
    this.observers = [];
  }

  addObserver(observer) {
    this.observers.push(observer);
  }

  notifyObservers() {
    this.observers.forEach(o => o.update(this.data));
  }

  setData(key, value) {
    this.data[key] = value;
    this.notifyObservers();
  }
}

// View — Observer
class View {
  constructor(controller) {
    this.controller = controller;
  }

  update(data) {
    console.log("تحديث الواجهة:", data);
  }

  onUserInput(key, value) {
    this.controller.handleInput(key, value);
  }
}

// Controller — Strategy
class Controller {
  constructor(model) {
    this.model = model;
  }

  handleInput(key, value) {
    // منطق التحقق والمعالجة
    this.model.setData(key, value);
  }
}

// الاستخدام
const model = new Model();
const controller = new Controller(model);
const view = new View(controller);

model.addObserver(view);

view.onUserInput("name", "أحمد"); // يمر عبر Controller -> Model -> View

MVC = Observer + Composite + Strategy

class UIComponent:
    def draw(self): ...

class Button(UIComponent):
    def __init__(self, text):
        self.text = text

    def draw(self):
        print(f"زر: {self.text}")

class Panel(UIComponent):
    def __init__(self):
        self.children = []

    def add(self, component):
        self.children.append(component)

    def draw(self):
        print("لوحة:")
        for child in self.children:
            child.draw()

panel = Panel()
panel.add(Button("إرسال"))
panel.add(Button("إلغاء"))
panel.draw()

class SaveController {
  handleInput(data) {
    console.log("حفظ البيانات");
  }
}

class PrintController {
  handleInput(data) {
    console.log("طباعة البيانات");
  }
}

Presentation Layer -> Business Layer -> Data Access Layer

// Model
class TodoModel {
  constructor() {
    this.items = [];
    this.listeners = [];
  }

  addListener(fn) { this.listeners.push(fn); }

  addItem(text) {
    this.items.push({ text, done: false });
    this.listeners.forEach(fn => fn(this.items));
  }

  toggleItem(index) {
    this.items[index].done = !this.items[index].done;
    this.listeners.forEach(fn => fn(this.items));
  }
}

// View (تنادي Controller)
class TodoView {
  constructor(controller) {
    this.controller = controller;
  }

  render(items) {
    console.clear();
    items.forEach((item, i) => {
      console.log(`${i + 1}. [${item.done ? '✓' : ' '}] ${item.text}`);
    });
  }

  addItem(text) {
    this.controller.onAddItem(text);
  }
}

// Controller
class TodoController {
  constructor(model) {
    this.model = model;
  }

  onAddItem(text) {
    this.model.addItem(text);
  }
}