/**
 * @license
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

import type { Key } from './hooks/useKeypress.js';
import type { KeyBinding, KeyBindingConfig } from '../config/keyBindings.js';
import { Command, defaultKeyBindings } from '../config/keyBindings.js';

/**
 * Matches a KeyBinding against an actual Key press
 * Pure data-driven matching logic
 */
function matchKeyBinding(keyBinding: KeyBinding, key: Key): boolean {
  // Check modifiers - follow original logic:
  // undefined = ignore this modifier (original behavior)
  // true = modifier must be pressed
  // false = modifier must NOT be pressed
  return (
    keyBinding.key === key.name &&
    (keyBinding.shift === undefined || key.shift === keyBinding.shift) &&
    (keyBinding.alt === undefined || key.alt === keyBinding.alt) &&
    (keyBinding.ctrl === undefined || key.ctrl === keyBinding.ctrl) &&
    (keyBinding.cmd === undefined || key.cmd === keyBinding.cmd)
  );
}

/**
 * Checks if a key matches any of the bindings for a command
 */
function matchCommand(
  command: Command,
  key: Key,
  config: KeyBindingConfig = defaultKeyBindings,
): boolean {
  const bindings = config[command];
  return bindings.some((binding) => matchKeyBinding(binding, key));
}

/**
 * Key matcher function type
 */
type KeyMatcher = (key: Key) => boolean;

/**
 * Type for key matchers mapped to Command enum
 */
export type KeyMatchers = {
  readonly [C in Command]: KeyMatcher;
};

/**
 * Creates key matchers from a key binding configuration
 */
export function createKeyMatchers(
  config: KeyBindingConfig = defaultKeyBindings,
): KeyMatchers {
  // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
  const matchers = {} as { [C in Command]: KeyMatcher };

  for (const command of Object.values(Command)) {
    matchers[command] = (key: Key) => matchCommand(command, key, config);
  }

  return matchers as KeyMatchers;
}

/**
 * Default key binding matchers using the default configuration
 */
export const keyMatchers: KeyMatchers = createKeyMatchers(defaultKeyBindings);

// Re-export Command for convenience
export { Command };