asciitorium/dist/core/FocusManager.js

an ASCII CLUI framework

import { Component } from './Component.js';
import { State } from './State.js';
export class FocusManager {
    constructor() {
        this.contextStack = [];
        this.index = 0;
        this.hotkeyMap = new Map();
        this.hotkeyVisibilityState = new State(false);
    }
    pushContext(components) {
        this.clearFocus();
        const focusables = components.filter((c) => c.focusable);
        this.contextStack.push(focusables);
        this.index = 0;
        this.setFocus(0);
    }
    popContext() {
        this.clearFocus();
        this.contextStack.pop();
        this.index = 0;
        this.setFocus(0);
    }
    get currentContext() {
        return this.contextStack[this.contextStack.length - 1] || [];
    }
    setFocus(index) {
        this.index = index;
        const current = this.currentContext[this.index];
        if (current) {
            current.hasFocus = true;
        }
    }
    clearFocus() {
        const current = this.currentContext[this.index];
        if (current) {
            current.hasFocus = false;
        }
    }
    focusNext() {
        if (this.currentContext.length === 0)
            return;
        this.clearFocus();
        this.index = (this.index + 1) % this.currentContext.length;
        this.setFocus(this.index);
    }
    // TODO: this doesn't work, still goes forward
    focusPrevious() {
        if (this.currentContext.length === 0)
            return;
        this.clearFocus();
        this.index =
            (this.index - 1 + this.currentContext.length) %
                this.currentContext.length;
        this.setFocus(this.index);
    }
    /**
     * Unified key handling for both hotkeys and navigation
     */
    handleKey(key) {
        // Get currently focused component
        const current = this.currentContext[this.index];
        // Check if focused component is in capture mode
        if (current?.captureModeActive) {
            // Only bypass keys (Tab, Shift+Tab) escape capture mode
            if (!Component.BYPASS_KEYS.includes(key)) {
                // Send key directly to component, skip hotkey processing
                const handled = current.handleEvent?.(key);
                return handled ?? false;
            }
        }
        // Handle hotkey visibility toggle first
        if (key === '`' || key === 'F1') {
            this.hotkeyVisibilityState.value = !this.hotkeyVisibilityState.value;
            return true;
        }
        // Handle direct hotkeys
        const hotkeyComponent = this.hotkeyMap.get(key.toLowerCase());
        if (hotkeyComponent) {
            // Focus the component
            const targetIndex = this.currentContext.indexOf(hotkeyComponent);
            if (targetIndex !== -1) {
                this.clearFocus();
                this.index = targetIndex;
                this.setFocus(targetIndex);
                // For buttons: trigger action
                if (hotkeyComponent.onClick) {
                    hotkeyComponent.onClick();
                }
                return true;
            }
        }
        // Handle navigation keys
        if (key === 'Tab') {
            this.focusNext();
            return true;
        }
        if (key === 'Shift+Tab') {
            this.focusPrevious();
            return true;
        }
        // Pass other keys to focused component
        const handled = current?.handleEvent?.(key);
        return handled ?? false;
    }
    reset(component) {
        const focusables = this.getFocusableDescendants(component).filter((c) => c.focusable);
        this.contextStack = [focusables];
        this.index = 0;
        this.setFocus(0);
        this.buildHotkeyMap(focusables);
    }
    refresh(component) {
        const currentlyFocused = this.currentContext[this.index];
        const focusables = this.getFocusableDescendants(component).filter((c) => c.focusable);
        this.contextStack = [focusables];
        this.buildHotkeyMap(focusables);
        // Try to find the same component in the new list
        if (currentlyFocused) {
            const newIndex = focusables.indexOf(currentlyFocused);
            if (newIndex !== -1) {
                this.index = newIndex;
                this.setFocus(newIndex);
                return;
            }
        }
        // Fallback to index 0 if current component not found
        this.index = 0;
        this.setFocus(0);
    }
    /**
     * Build hotkey map from focusable components
     */
    buildHotkeyMap(focusableComponents) {
        this.hotkeyMap.clear();
        for (const component of focusableComponents) {
            if (component.hotkey) {
                if (this.isReservedKey(component.hotkey)) {
                    console.error(`ERROR: Hotkey '${component.hotkey}' is reserved for system navigation and cannot be used. Reserved keys: ${Array.from(FocusManager.RESERVED_KEYS).join(', ')}`);
                }
                else {
                    const key = component.hotkey.toLowerCase();
                    if (this.hotkeyMap.has(key)) {
                        console.warn(`Hotkey '${component.hotkey}' is already assigned to another component`);
                    }
                    else {
                        this.hotkeyMap.set(key, component);
                    }
                }
            }
        }
    }
    isReservedKey(key) {
        return FocusManager.RESERVED_KEYS.has(key) || FocusManager.RESERVED_KEYS.has(key.toLowerCase());
    }
    getFocusableDescendants(parent) {
        const focusables = [];
        for (const child of parent.getChildren()) {
            // Skip invisible components for focus navigation
            if (!child.visible)
                continue;
            if (child.focusable) {
                focusables.push(child);
            }
            // Now all components can have children, so recursively check all
            focusables.push(...this.getFocusableDescendants(child));
        }
        return focusables;
    }
}
// Reserved keys that should not be used for hotkeys
FocusManager.RESERVED_KEYS = new Set([
    'ArrowUp', 'ArrowDown', 'ArrowLeft', 'ArrowRight', // Arrow keys
    'Tab', 'Enter', ' ', 'Escape', // Navigation and control
    'Backspace', 'Delete', 'Home', 'End', // Text editing
    'PageUp', 'PageDown', // Scrolling
]);