User Interface

/**
 * Classic Editor UI interface
 */
interface ClassicEditorUI {
  /**
   * Main UI container element
   */
  readonly element: HTMLElement;
  
  /**
   * Main UI view component
   */
  readonly view: ClassicEditorUIView;
  
  /**
   * Focus tracking utilities
   */
  readonly focusTracker: FocusTracker;
  
  /**
   * Component factory for creating UI elements
   */
  readonly componentFactory: ComponentFactory;
  
  /**
   * Tooltip manager
   */
  readonly tooltipManager: TooltipManager;
  
  /**
   * Power management for the UI
   */
  readonly poweredBy: PoweredBy;
  
  /**
   * Initialize the UI
   */
  init(): void;
  
  /**
   * Destroy the UI
   */
  destroy(): void;
  
  /**
   * Update the UI
   */
  update(): void;
}

/**
 * Classic Editor UI View
 */
interface ClassicEditorUIView {
  /**
   * Main toolbar view
   */
  readonly toolbar: ToolbarView;
  
  /**
   * Editable area view
   */
  readonly editable: EditableUIView;
  
  /**
   * Sticky panel for toolbar
   */
  readonly stickyPanel: StickyPanelView;
  
  /**
   * Main UI element
   */
  readonly element: HTMLElement;
}

// Access main UI components
const ui = editor.ui;
const mainElement = ui.element;
const toolbar = ui.view.toolbar;
const editable = ui.view.editable;

// Get toolbar height for layout calculations
const toolbarHeight = toolbar.element.offsetHeight;
console.log('Toolbar height:', toolbarHeight);

// Access sticky panel for viewport offset
const stickyPanel = ui.view.stickyPanel;
stickyPanel.viewportTopOffset = 50; // Account for fixed header

// Update UI manually if needed
ui.update();

/**
 * Component factory for creating UI elements
 */
interface ComponentFactory {
  /**
   * Create a component by name
   */  
  create(name: string): View;
  
  /**
   * Add component definition
   */
  add(name: string, callback: (locale: Locale) => View): void;
  
  /**
   * Check if component exists
   */
  has(name: string): boolean;
  
  /**
   * Get component names
   */
  names(): Array<string>;
  
  /**
   * Destroy factory
   */
  destroy(): void;
}

/**
 * Button view for creating toolbar buttons
 */
interface ButtonView extends View {
  /**
   * Button label text
   */
  label: string;
  
  /**
   * Button icon (SVG string)
   */
  icon: string;
  
  /**
   * Button tooltip text
   */
  tooltip: string | boolean;
  
  /**
   * Whether button is enabled
   */
  isEnabled: boolean;
  
  /**
   * Whether button is visible
   */
  isVisible: boolean;
  
  /**
   * Whether button is toggled on
   */
  isOn: boolean;
  
  /**
   * Button click handler
   */
  on(eventName: 'execute', callback: () => void): void;
}

/**
 * Dropdown view for creating dropdown components
 */
interface DropdownView extends View {
  /**
   * Dropdown button view
   */
  readonly buttonView: ButtonView;
  
  /**
   * Dropdown panel view
   */
  readonly panelView: DropdownPanelView;
  
  /**
   * Whether dropdown is open
   */
  isOpen: boolean;
  
  /**
   * Open the dropdown
   */
  open(): void;
  
  /**
   * Close the dropdown
   */
  close(): void;
}

// Access component factory
const componentFactory = editor.ui.componentFactory;

// Create custom button
componentFactory.add('customButton', locale => {
  const button = new ButtonView(locale);
  
  button.set({
    label: 'Custom Action',
    icon: '<svg>...</svg>',
    tooltip: true,
    isEnabled: true
  });
  
  // Handle button click
  button.on('execute', () => {
    console.log('Custom button clicked!');
    editor.execute('bold'); // Example action
  });
  
  return button;
});

// Create the button instance
const customButton = componentFactory.create('customButton');

// Add button to toolbar
editor.ui.view.toolbar.items.add(customButton);

// Create dropdown component
componentFactory.add('customDropdown', locale => {
  const dropdown = createDropdown(locale);
  
  dropdown.buttonView.set({
    label: 'Custom Dropdown',
    icon: '<svg>...</svg>',
    tooltip: 'Custom dropdown menu'
  });
  
  // Add items to dropdown
  const items = new Collection();
  items.add({
    type: 'button',
    model: new Model({
      label: 'Option 1',
      withText: true
    })
  });
  
  addListToDropdown(dropdown, items);
  
  return dropdown;
});

/**
 * Toolbar view for managing toolbar items
 */
interface ToolbarView extends View {
  /**
   * Collection of toolbar items
   */
  readonly items: ViewCollection;
  
  /**
   * Toolbar options
   */
  options: {
    shouldGroupWhenFull?: boolean;
    isFloating?: boolean;
  };
  
  /**
   * Maximum width before grouping
   */
  maxWidth: string;
  
  /**
   * Whether toolbar should group items
   */
  shouldGroupWhenFull: boolean;
  
  /**
   * Add item to toolbar
   */
  addItem(item: View, index?: number): void;
  
  /**
   * Remove item from toolbar
   */
  removeItem(item: View): void;
  
  /**
   * Focus first toolbar item
   */
  focus(): void;
  
  /**
   * Focus last toolbar item
   */
  focusLast(): void;
}

/**
 * View collection for managing UI components
 */
interface ViewCollection {
  /**
   * Add view to collection
   */
  add(view: View, index?: number): void;
  
  /**
   * Remove view from collection
   */
  remove(view: View): void;
  
  /**
   * Get view by index
   */
  get(index: number): View;
  
  /**
   * Number of views in collection
   */
  readonly length: number;
  
  /**
   * Find view by predicate
   */
  find(predicate: (view: View) => boolean): View | undefined;
}

// Access toolbar
const toolbar = editor.ui.view.toolbar;

// Add custom separator
const separator = new ToolbarSeparatorView();
toolbar.items.add(separator);

// Add custom button to toolbar
const customButton = editor.ui.componentFactory.create('customButton');
toolbar.items.add(customButton, 5); // Insert at position 5

// Remove item from toolbar
const boldButton = toolbar.items.find(item => 
  item.label === 'Bold'
);
if (boldButton) {
  toolbar.items.remove(boldButton);
}

// Configure toolbar grouping
toolbar.options.shouldGroupWhenFull = false;

// Focus toolbar
toolbar.focus();

// Monitor toolbar changes
toolbar.items.on('add', (evt, item, index) => {
  console.log(`Item added to toolbar at position ${index}:`, item.label);
});

toolbar.items.on('remove', (evt, item, index) => {
  console.log(`Item removed from toolbar at position ${index}:`, item.label);
});

/**
 * Focus tracker for managing focus state
 */
interface FocusTracker {
  /**
   * Whether any tracked element is focused
   */
  readonly isFocused: boolean;
  
  /**
   * Currently focused element
   */
  readonly focusedElement: HTMLElement | null;
  
  /**
   * Add element to focus tracking
   */
  add(element: HTMLElement): void;
  
  /**
   * Remove element from focus tracking
   */
  remove(element: HTMLElement): void;
  
  /**
   * Destroy focus tracker
   */
  destroy(): void;
  
  /**
   * Focus change events
   */
  on(eventName: 'change:isFocused', callback: (evt: EventInfo, name: string, value: boolean) => void): void;
  on(eventName: 'change:focusedElement', callback: (evt: EventInfo, name: string, element: HTMLElement | null) => void): void;
}

// Access focus tracker
const focusTracker = editor.ui.focusTracker;

// Check if editor has focus
console.log('Editor is focused:', focusTracker.isFocused);
console.log('Focused element:', focusTracker.focusedElement);

// Add custom element to focus tracking
const customPanel = document.createElement('div');
focusTracker.add(customPanel);

// Listen for focus changes
focusTracker.on('change:isFocused', (evt, propertyName, isFocused) => {
  console.log('Editor focus changed:', isFocused);
  
  if (isFocused) {
    document.body.classList.add('editor-focused');
  } else {
    document.body.classList.remove('editor-focused');
  }
});

focusTracker.on('change:focusedElement', (evt, propertyName, element) => {
  if (element) {
    console.log('Focus moved to:', element.tagName, element.className);
  }
});

// Clean up when no longer needed
focusTracker.remove(customPanel);

/**
 * Tooltip manager for displaying contextual help
 */
interface TooltipManager {
  /**
   * Show tooltip for element
   */
  show(element: HTMLElement, options: TooltipOptions): void;
  
  /**
   * Hide tooltip
   */
  hide(): void;
  
  /**
   * Destroy tooltip manager
   */
  destroy(): void;
}

/**
 * Tooltip configuration options
 */
interface TooltipOptions {
  /**
   * Tooltip text content
   */
  text: string;
  
  /**
   * Tooltip position relative to element
   */
  position?: 'top' | 'bottom' | 'left' | 'right';
  
  /**
   * Additional CSS classes
   */
  class?: string;
  
  /**
   * Delay before showing tooltip
   */
  delay?: number;
}

// Access tooltip manager
const tooltipManager = editor.ui.tooltipManager;

// Show custom tooltip for element
const customElement = document.querySelector('.custom-button');
tooltipManager.show(customElement, {
  text: 'This is a custom tooltip',
  position: 'top',
  class: 'custom-tooltip',
  delay: 500
});

// Hide tooltip manually
setTimeout(() => {
  tooltipManager.hide();
}, 3000);

// Create button with tooltip
const buttonWithTooltip = editor.ui.componentFactory.create('customTooltipButton');
buttonWithTooltip.tooltip = 'Click me for custom action';

// Tooltip will automatically show on hover

/**
 * Base view class for all UI components
 */
interface View {
  /**
   * View element
   */
  readonly element: HTMLElement;
  
  /**
   * View locale
   */
  readonly locale: Locale;
  
  /**
   * Whether view is rendered
   */
  readonly isRendered: boolean;
  
  /**
   * View template
   */
  template: Template;
  
  /**
   * Render the view
   */
  render(): void;
  
  /**
   * Destroy the view
   */
  destroy(): void;
  
  /**
   * Set multiple properties
   */
  set(properties: Record<string, any>): void;
  
  /**
   * Bind property to another observable
   */
  bind(property: string): BindChain;
}

/**
 * Template for defining view structure
 */
interface Template {
  /**
   * HTML tag name
   */
  tag: string;
  
  /**
   * Element attributes
   */
  attributes?: Record<string, any>;
  
  /**
   * CSS classes
   */
  children?: Array<View | Template | string>;
  
  /**
   * Child elements
   */
  on?: Record<string, Function>;
}

// Create custom view
class CustomPanelView extends View {
  constructor(locale) {
    super(locale);
    
    this.set({
      isVisible: true,
      title: 'Custom Panel'
    });
    
    this.template = new Template({
      tag: 'div',
      attributes: {
        class: ['custom-panel'],
        style: {
          display: this.bindTemplate.if('isVisible', 'block', 'none')
        }
      },
      children: [
        {
          tag: 'h3',
          children: [this.bindTemplate.to('title')]
        },
        {
          tag: 'div',
          attributes: {
            class: ['custom-panel-content']
          }
        }
      ]
    });
  }
}

// Create and use custom view
const customPanel = new CustomPanelView(editor.locale);
customPanel.render();
document.body.appendChild(customPanel.element);

// Update view properties
customPanel.set({
  title: 'Updated Panel Title',
  isVisible: false
});

// Clean up
customPanel.destroy();