Utility Functions

/**
 * Check if a value represents a cancelled prompt
 * @param value - Value to check
 * @returns true if value is the cancel symbol
 */
function isCancel(value: unknown): value is symbol;

import { TextPrompt, isCancel } from '@clack/core';

const prompt = new TextPrompt({
  render() {
    return `Enter your name:\n${this.valueWithCursor}`;
  }
});

const result = await prompt.prompt();

// Check if user cancelled the prompt
if (isCancel(result)) {
  console.log('User cancelled the operation');
  process.exit(0);
}

// Safe to use result as string now
console.log(`Hello, ${result}!`);

// Can also be used with any prompt type
import { SelectPrompt, ConfirmPrompt } from '@clack/core';

const selectResult = await new SelectPrompt({
  render() { /* ... */ },
  options: [/* ... */]
}).prompt();

if (isCancel(selectResult)) {
  console.log('Selection cancelled');
  return;
}

const confirmResult = await new ConfirmPrompt({
  render() { /* ... */ },
  active: 'Yes',
  inactive: 'No'
}).prompt();

if (isCancel(confirmResult)) {
  console.log('Confirmation cancelled');
  return;
}

/**
 * Block terminal input/output with cleanup function
 * @param options - Configuration options for blocking behavior
 * @returns Cleanup function to restore terminal state
 */
function block(options?: {
  input?: NodeJS.ReadStream & { fd: 0 };
  output?: NodeJS.WriteStream & { fd: 1 };
  overwrite?: boolean;
  hideCursor?: boolean;
}): () => void;

import { block } from '@clack/core';

// Basic terminal blocking
const cleanup = block();

// Perform operations while terminal is blocked
console.log('Processing...');
await performLongOperation();

// Restore terminal state
cleanup();

// Terminal blocking with custom options
const cleanup2 = block({
  hideCursor: true,
  overwrite: true
});

// Show progress indicator
for (let i = 0; i <= 100; i += 10) {
  process.stdout.write(`\rProgress: ${i}%`);
  await new Promise(resolve => setTimeout(resolve, 100));
}

cleanup2();

// Block with custom streams
import { createReadStream, createWriteStream } from 'fs';

const customInput = createReadStream('/dev/tty');
const customOutput = createWriteStream('/dev/tty');

const cleanup3 = block({
  input: customInput,
  output: customOutput,
  hideCursor: true
});

// Custom terminal operations
cleanup3();

/**
 * Update global Clack settings
 * @param updates - Settings to update
 */
function updateSettings(updates: ClackSettings): void;

/**
 * Global settings configuration interface
 */
interface ClackSettings {
  /** Key aliases for different actions */
  aliases?: Record<string, Action>;
}

/**
 * Available actions that can be customized
 */
type Action = 'up' | 'down' | 'left' | 'right' | 'space' | 'enter' | 'cancel';

import { updateSettings } from '@clack/core';

// Customize key bindings
updateSettings({
  aliases: {
    'k': 'up',           // Use 'k' for up navigation
    'w': 'up',           // Use 'w' for up navigation
    'j': 'down',         // Use 'j' for down navigation
    's': 'down',         // Use 's' for down navigation
    'h': 'left',         // Use 'h' for left navigation
    'a': 'left',         // Use 'a' for left navigation
    'l': 'right',        // Use 'l' for right navigation
    'd': 'right',        // Use 'd' for right navigation
    'q': 'cancel'        // Use 'q' to cancel
  }
});

// Vim-style navigation
updateSettings({
  aliases: {
    'k': 'up',
    'j': 'down',
    'h': 'left',
    'l': 'right',
    'q': 'cancel'
  }
});

// Gaming-style WASD navigation
updateSettings({
  aliases: {
    'w': 'up',
    's': 'down',
    'a': 'left',
    'd': 'right',
    'e': 'enter',
    'q': 'cancel'
  }
});

// Clear custom aliases (use default keys only)
updateSettings({
  aliases: {}  // Empty object removes custom aliases, using only default keys
});