/* eslint-disable @typescript-eslint/no-use-before-define */
/* eslint-disable no-restricted-syntax */
/* eslint-disable no-plusplus */
/* eslint-disable @typescript-eslint/no-redeclare */
import { isOSX } from '@difizen/mana-common';

export type KeySequence = KeyCode[];
export namespace KeySequence {
  export function equals(a: KeySequence, b: KeySequence): boolean {
    if (a.length !== b.length) {
      return false;
    }

    for (let i = 0; i < a.length; i++) {
      if (!a[i].equals(b[i])) {
        return false;
      }
    }
    return true;
  }

  export enum CompareResult {
    NONE = 0,
    PARTIAL,
    SHADOW,
    FULL,
  }

  /* Compares two KeySequences, returns:
   * FULL if the KeySequences are the same.
   * PARTIAL if the KeySequence a part of b.
   * SHADOW if the KeySequence b part of a.
   * NONE if the KeySequences are not the same at all.
   */
  export function compare(a: KeySequence, b: KeySequence): CompareResult {
    let first = a;
    let second = b;
    let shadow = false;

    if (b.length < a.length) {
      first = b;
      second = a;
      shadow = true;
    }

    for (let i = 0; i < first.length; i++) {
      if (first[i].equals(second[i]) === false) {
        return KeySequence.CompareResult.NONE;
      }
    }
    if (first.length < second.length) {
      if (shadow === false) {
        return KeySequence.CompareResult.PARTIAL;
      }
      return KeySequence.CompareResult.SHADOW;
    }
    return KeySequence.CompareResult.FULL;
  }

  export function parse(keybinding: string): KeySequence {
    const keyCodes = [];
    const rawKeyCodes = keybinding.trim().split(/\s+/g);
    for (const rawKeyCode of rawKeyCodes) {
      const keyCode = KeyCode.parse(rawKeyCode);
      if (keyCode !== undefined) {
        keyCodes.push(keyCode);
      }
    }
    return keyCodes;
  }
}

/**
 * The key sequence for this binding. This key sequence should consist of one or more key strokes. Key strokes
 * consist of one or more keys held down at the same time. This should be zero or more modifier keys, and zero or one other key.
 * Since `M2+M3+<Key>` (Alt+Shift+<Key>) is reserved on MacOS X for writing special characters, such bindings are commonly
 * undefined for platform MacOS X and redefined as `M1+M3+<Key>`. The rule applies on the `M3+M2+<Key>` sequence.
 */
export type Keystroke = {
  readonly first?: Key | undefined;
  readonly modifiers?: KeyModifier[] | undefined;
};

export type KeyCodeSchema = {
  key?: Partial<Key> | undefined;
  ctrl?: boolean | undefined;
  shift?: boolean | undefined;
  alt?: boolean | undefined;
  meta?: boolean | undefined;
  character?: string | undefined;
};

/**
 * Representation of a pressed key combined with key modifiers.
 */
export class KeyCode {
  public readonly key: Key | undefined;

  public readonly ctrl: boolean;

  public readonly shift: boolean;

  public readonly alt: boolean;

  public readonly meta: boolean;

  public readonly character: string | undefined;

  public constructor(schema: KeyCodeSchema) {
    const { key } = schema;
    if (key) {
      if (key.code && key.keyCode && key.easyString) {
        this.key = key as Key;
      } else if (key.code) {
        this.key = Key.getKey(key.code);
      } else if (key.keyCode) {
        this.key = Key.getKey(key.keyCode);
      }
    }
    this.ctrl = !!schema.ctrl;
    this.shift = !!schema.shift;
    this.alt = !!schema.alt;
    this.meta = !!schema.meta;
    this.character = schema.character;
  }

  /**
   * Return true if this KeyCode only contains modifiers.
   */
  public isModifierOnly(): boolean {
    return this.key === undefined;
  }

  /**
   * Return true if the given KeyCode is equal to this one.
   */
  equals(other: KeyCode): boolean {
    if (
      (this.key && (!other.key || this.key.code !== other.key.code)) ||
      (!this.key && other.key)
    ) {
      return false;
    }
    return (
      this.ctrl === other.ctrl &&
      this.alt === other.alt &&
      this.shift === other.shift &&
      this.meta === other.meta
    );
  }

  /*
   * Return a keybinding string compatible with the `Keybinding.keybinding` property.
   */
  toString(): string {
    const result = [];
    if (this.meta) {
      result.push(SpecialCases.META);
    }
    if (this.shift) {
      result.push(Key.SHIFT_LEFT.easyString);
    }
    if (this.alt) {
      result.push(Key.ALT_LEFT.easyString);
    }
    if (this.ctrl) {
      result.push(Key.CONTROL_LEFT.easyString);
    }
    if (this.key) {
      result.push(this.key.easyString);
    }
    return result.join('+');
  }

  /**
   * Create a KeyCode from one of several input types.
   */
  public static createKeyCode(
    input: KeyboardEvent | Keystroke | KeyCodeSchema | string,
    eventDispatch: 'code' | 'keyCode' = 'code',
  ): KeyCode {
    if (typeof input === 'string') {
      const parts = input.split('+');
      if (!KeyCode.isModifierString(parts[0])) {
        return KeyCode.createKeyCode({
          first: Key.getKey(parts[0]),
          modifiers: parts.slice(1) as KeyModifier[],
        });
      }
      return KeyCode.createKeyCode({ modifiers: parts as KeyModifier[] });
    }
    if (KeyCode.isKeyboardEvent(input)) {
      const key = KeyCode.toKey(input, eventDispatch);
      return new KeyCode({
        key: Key.isModifier(key.code) ? undefined : key,
        meta: isOSX && input.metaKey,
        shift: input.shiftKey,
        alt: input.altKey,
        ctrl: input.ctrlKey,
        character: KeyCode.toCharacter(input),
      });
    }
    if ((input as Keystroke).first || (input as Keystroke).modifiers) {
      const keystroke = input as Keystroke;
      const schema: KeyCodeSchema = {
        key: keystroke.first,
      };
      if (keystroke.modifiers) {
        if (isOSX) {
          schema.meta = keystroke.modifiers.some((mod) => mod === KeyModifier.CtrlCmd);
          schema.ctrl = keystroke.modifiers.some((mod) => mod === KeyModifier.MacCtrl);
        } else {
          schema.meta = false;
          schema.ctrl = keystroke.modifiers.some((mod) => mod === KeyModifier.CtrlCmd);
        }
        schema.shift = keystroke.modifiers.some((mod) => mod === KeyModifier.Shift);
        schema.alt = keystroke.modifiers.some((mod) => mod === KeyModifier.Alt);
      }
      return new KeyCode(schema);
    }
    return new KeyCode(input as KeyCodeSchema);
  }

  private static keybindings: Record<string, KeyCode> = {};

  /* Reset the key hashmap, this is for testing purposes.  */
  public static resetKeyBindings(): void {
    KeyCode.keybindings = {};
  }

  /**
   * Parses a string and returns a KeyCode object.
   * @param keybinding String representation of a keybinding
   */
  public static parse(keybinding: string): KeyCode {
    if (KeyCode.keybindings[keybinding]) {
      return KeyCode.keybindings[keybinding];
    }

    const schema: KeyCodeSchema = {};
    const keys = [];
    let currentKey = '';
    for (const character of keybinding.trim().toLowerCase()) {
      if (currentKey && (character === '-' || character === '+')) {
        keys.push(currentKey);
        currentKey = '';
      } else if (character !== '+') {
        currentKey += character;
      }
    }
    if (currentKey) {
      keys.push(currentKey);
    }
    /* If duplicates i.e ctrl+ctrl+a or alt+alt+b or b+alt+b it is invalid */
    if (keys.length !== new Set(keys).size) {
      throw new Error(`Can't parse keybinding ${keybinding} Duplicate modifiers`);
    }

    for (let keyString of keys) {
      if (SPECIAL_ALIASES[keyString] !== undefined) {
        keyString = SPECIAL_ALIASES[keyString];
      }
      const key = EASY_TO_KEY[keyString];

      /* meta only works on macOS */
      if (keyString === SpecialCases.META) {
        if (isOSX) {
          schema.meta = true;
        } else {
          throw new Error(`Can't parse keybinding ${keybinding} meta is for OSX only`);
        }
        /* ctrlcmd for M1 keybindings that work on both macOS and other platforms */
      } else if (keyString === SpecialCases.CTRLCMD) {
        if (isOSX) {
          schema.meta = true;
        } else {
          schema.ctrl = true;
        }
      } else if (Key.isKey(key)) {
        if (Key.isModifier(key.code)) {
          if (
            key.code === Key.CONTROL_LEFT.code ||
            key.code === Key.CONTROL_RIGHT.code
          ) {
            schema.ctrl = true;
          } else if (
            key.code === Key.SHIFT_LEFT.code ||
            key.code === Key.SHIFT_RIGHT.code
          ) {
            schema.shift = true;
          } else if (
            key.code === Key.ALT_LEFT.code ||
            key.code === Key.ALT_RIGHT.code
          ) {
            schema.alt = true;
          }
        } else {
          schema.key = key;
        }
      } else {
        throw new Error(`Unrecognized key '${keyString}' in '${keybinding}'`);
      }
    }

    KeyCode.keybindings[keybinding] = new KeyCode(schema);
    return KeyCode.keybindings[keybinding];
  }
}

export namespace KeyCode {
  /**
   * Determines a `true` of `false` value for the key code argument.
   */
  export type Predicate = (keyCode: KeyCode) => boolean;

  /*
   * Return true if the string is a modifier M1 to M4.
   */
  export function isModifierString(key: string): boolean {
    return (
      key === KeyModifier.CtrlCmd ||
      key === KeyModifier.Shift ||
      key === KeyModifier.Alt ||
      key === KeyModifier.MacCtrl
    );
  }

  /**
   * Different scopes have different execution environments. This means that they have different built-ins
   * (different global object, different constructors, etc.). This may result in unexpected results. For instance,
   * `[] instanceof window.frames[0].Array` will return `false`, because `Array.prototype !== window.frames[0].Array`
   * and arrays inherit from the former.
   * See: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/instanceof
   *
   * Note: just add another check if the current `event.type` checking is insufficient.
   */
  export function isKeyboardEvent(
    event: object & { readonly type?: string },
  ): event is KeyboardEvent {
    if (typeof KeyboardEvent === 'undefined') {
      // This can happen in tests
      return false;
    }
    if (event instanceof KeyboardEvent) {
      return true;
    }
    const { type } = event;
    if (type) {
      return type === 'keypress' || type === 'keydown' || type === 'keyup';
    }
    return false;
  }

  /**
   * Determine the pressed key of a keyboard event. This key should correspond to the physical key according
   * to a standard US keyboard layout. International keyboard layouts are handled by `KeyboardLayoutService`.
   *
   * `keyIdentifier` is used to access this deprecated field:
   * https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyIdentifier
   */
  export function toKey(
    event: KeyboardEvent,
    dispatch: 'code' | 'keyCode' = 'code',
  ): Key {
    const { code } = event;
    if (code && dispatch === 'code') {
      if (isOSX) {
        // https://github.com/eclipse-mana/mana/issues/4986
        const char = event.key;
        if (code === 'IntlBackslash' && (char === '`' || char === '~')) {
          return Key.BACKQUOTE;
        }
        if (code === 'Backquote' && (char === '§' || char === '±')) {
          return Key.INTL_BACKSLASH;
        }
      }

      // https://github.com/eclipse-mana/mana/issues/7315
      if (code.startsWith('Numpad') && event.key && event.key.length > 1) {
        const k = Key.getKey(event.key);
        if (k) {
          return k;
        }
      }

      const key = Key.getKey(code);
      if (key) {
        return key;
      }
    }

    // tslint:disable-next-line: deprecation
    const { keyCode } = event;
    if (keyCode) {
      const key = Key.getKey(keyCode);
      if (key) {
        return key;
      }
    }

    const { keyIdentifier } = event as KeyboardEvent & { keyIdentifier?: string };
    if (keyIdentifier) {
      const key = Key.getKey(keyIdentifier);
      if (key) {
        return key;
      }
    }
    throw new Error(`Cannot get key code from the keyboard event: ${event}.`);
  }

  /**
   * Determine the actual printable character that is generated from a pressed key.
   * If the key does not correspond to a printable character, `undefined` is returned.
   * The result may be altered by modifier keys.
   */
  export function toCharacter(event: KeyboardEvent): string | undefined {
    const { key } = event;
    // Use the key property if it contains exactly one unicode character
    if (key && Array.from(key).length === 1) {
      return key;
    }
    const { charCode } = event;
    // Use the charCode property if it does not correspond to a unicode control character
    if (charCode && charCode > 0x1f && !(charCode >= 0x80 && charCode <= 0x9f)) {
      return String.fromCharCode(charCode);
    }
    return undefined;
  }
}

export enum KeyModifier {
  /**
   * M1 is the COMMAND key on MacOS X, and the CTRL key on most other platforms.
   */
  CtrlCmd = 'M1',
  /**
   * M2 is the SHIFT key.
   */
  Shift = 'M2',
  /**
   * M3 is the Option key on MacOS X, and the ALT key on most other platforms.
   */
  Alt = 'M3',
  /**
   * M4 is the CTRL key on MacOS X, and is undefined on other platforms.
   */
  MacCtrl = 'M4',
}

export namespace KeyModifier {
  /**
   * The CTRL key, independently of the platform.
   * _Note:_ In general `KeyModifier.CtrlCmd` should be preferred over this constant.
   */
  export const CTRL: KeyModifier.MacCtrl | KeyModifier.CtrlCmd = isOSX
    ? KeyModifier.MacCtrl
    : KeyModifier.CtrlCmd;
  /**
   * An alias for the SHIFT key (`KeyModifier.Shift`).
   */
  export const SHIFT: KeyModifier.Shift = KeyModifier.Shift;

  /**
   * `true` if the argument represents a modifier. Otherwise, `false`.
   */
  export function isModifier(key: string | undefined): boolean {
    if (key) {
      switch (key) {
        case 'M1': // Fall through.
        case 'M2': // Fall through.
        case 'M3': // Fall through.
        case 'M4':
          return true;
        default:
          return false;
      }
    }
    return false;
  }
}

export type Key = {
  readonly code: string;
  readonly keyCode: number;
  readonly easyString: string;
};

const CODE_TO_KEY: Record<string, Key> = {};
const KEY_CODE_TO_KEY: Record<number, Key> = {};
const EASY_TO_KEY: Record<string, Key> = {}; // From 'ctrl' to Key structure
const MODIFIERS: Key[] = [];

const SPECIAL_ALIASES: Record<string, string> = {
  option: 'alt',
  command: 'meta',
  cmd: 'meta',
  return: 'enter',
  esc: 'escape',
  mod: 'ctrl',
  ins: 'insert',
  del: 'delete',
  control: 'ctrl',
};

export namespace SpecialCases {
  export const META = 'meta';
  export const CTRLCMD = 'ctrlcmd';
}

export namespace Key {
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  export function isKey(arg: any): arg is Key {
    return typeof arg === 'object' && 'code' in arg && 'keyCode' in arg;
  }

  export function getKey(arg: string | number): Key | undefined {
    if (typeof arg === 'number') {
      return KEY_CODE_TO_KEY[arg];
    }
    return CODE_TO_KEY[arg];
  }

  export function isModifier(arg: string | number): boolean {
    if (typeof arg === 'number') {
      return MODIFIERS.find((key) => key.keyCode === arg) !== undefined;
    }
    return MODIFIERS.find((key) => key.code === arg) !== undefined;
  }

  export function equals(key: Key, keyCode: KeyCode): boolean {
    return !!keyCode.key && key.keyCode === keyCode.key.keyCode;
  }

  export const BACKSPACE: Key = {
    code: 'Backspace',
    keyCode: 8,
    easyString: 'backspace',
  };
  export const TAB: Key = { code: 'Tab', keyCode: 9, easyString: 'tab' };
  export const ENTER: Key = { code: 'Enter', keyCode: 13, easyString: 'enter' };
  export const ESCAPE: Key = { code: 'Escape', keyCode: 27, easyString: 'escape' };
  export const SPACE: Key = { code: 'Space', keyCode: 32, easyString: 'space' };
  export const PAGE_UP: Key = { code: 'PageUp', keyCode: 33, easyString: 'pageup' };
  export const PAGE_DOWN: Key = {
    code: 'PageDown',
    keyCode: 34,
    easyString: 'pagedown',
  };
  export const END: Key = { code: 'End', keyCode: 35, easyString: 'end' };
  export const HOME: Key = { code: 'Home', keyCode: 36, easyString: 'home' };
  export const ARROW_LEFT: Key = { code: 'ArrowLeft', keyCode: 37, easyString: 'left' };
  export const ARROW_UP: Key = { code: 'ArrowUp', keyCode: 38, easyString: 'up' };
  export const ARROW_RIGHT: Key = {
    code: 'ArrowRight',
    keyCode: 39,
    easyString: 'right',
  };
  export const ARROW_DOWN: Key = { code: 'ArrowDown', keyCode: 40, easyString: 'down' };
  export const INSERT: Key = { code: 'Insert', keyCode: 45, easyString: 'insert' };
  export const DELETE: Key = { code: 'Delete', keyCode: 46, easyString: 'delete' };

  export const SHIFT_LEFT: Key = {
    code: 'ShiftLeft',
    keyCode: 16,
    easyString: 'shift',
  };
  export const SHIFT_RIGHT: Key = {
    code: 'ShiftRight',
    keyCode: 16,
    easyString: 'shift',
  };
  export const CONTROL_LEFT: Key = {
    code: 'ControlLeft',
    keyCode: 17,
    easyString: 'ctrl',
  };
  export const CONTROL_RIGHT: Key = {
    code: 'ControlRight',
    keyCode: 17,
    easyString: 'ctrl',
  };
  export const ALT_LEFT: Key = { code: 'AltLeft', keyCode: 18, easyString: 'alt' };
  export const ALT_RIGHT: Key = { code: 'AltRight', keyCode: 18, easyString: 'alt' };
  export const CAPS_LOCK: Key = {
    code: 'CapsLock',
    keyCode: 20,
    easyString: 'capslock',
  };
  export const OS_LEFT: Key = { code: 'OSLeft', keyCode: 91, easyString: 'super' };
  export const OS_RIGHT: Key = { code: 'OSRight', keyCode: 92, easyString: 'super' };

  export const DIGIT0: Key = { code: 'Digit0', keyCode: 48, easyString: '0' };
  export const DIGIT1: Key = { code: 'Digit1', keyCode: 49, easyString: '1' };
  export const DIGIT2: Key = { code: 'Digit2', keyCode: 50, easyString: '2' };
  export const DIGIT3: Key = { code: 'Digit3', keyCode: 51, easyString: '3' };
  export const DIGIT4: Key = { code: 'Digit4', keyCode: 52, easyString: '4' };
  export const DIGIT5: Key = { code: 'Digit5', keyCode: 53, easyString: '5' };
  export const DIGIT6: Key = { code: 'Digit6', keyCode: 54, easyString: '6' };
  export const DIGIT7: Key = { code: 'Digit7', keyCode: 55, easyString: '7' };
  export const DIGIT8: Key = { code: 'Digit8', keyCode: 56, easyString: '8' };
  export const DIGIT9: Key = { code: 'Digit9', keyCode: 57, easyString: '9' };

  export const KEY_A: Key = { code: 'KeyA', keyCode: 65, easyString: 'a' };
  export const KEY_B: Key = { code: 'KeyB', keyCode: 66, easyString: 'b' };
  export const KEY_C: Key = { code: 'KeyC', keyCode: 67, easyString: 'c' };
  export const KEY_D: Key = { code: 'KeyD', keyCode: 68, easyString: 'd' };
  export const KEY_E: Key = { code: 'KeyE', keyCode: 69, easyString: 'e' };
  export const KEY_F: Key = { code: 'KeyF', keyCode: 70, easyString: 'f' };
  export const KEY_G: Key = { code: 'KeyG', keyCode: 71, easyString: 'g' };
  export const KEY_H: Key = { code: 'KeyH', keyCode: 72, easyString: 'h' };
  export const KEY_I: Key = { code: 'KeyI', keyCode: 73, easyString: 'i' };
  export const KEY_J: Key = { code: 'KeyJ', keyCode: 74, easyString: 'j' };
  export const KEY_K: Key = { code: 'KeyK', keyCode: 75, easyString: 'k' };
  export const KEY_L: Key = { code: 'KeyL', keyCode: 76, easyString: 'l' };
  export const KEY_M: Key = { code: 'KeyM', keyCode: 77, easyString: 'm' };
  export const KEY_N: Key = { code: 'KeyN', keyCode: 78, easyString: 'n' };
  export const KEY_O: Key = { code: 'KeyO', keyCode: 79, easyString: 'o' };
  export const KEY_P: Key = { code: 'KeyP', keyCode: 80, easyString: 'p' };
  export const KEY_Q: Key = { code: 'KeyQ', keyCode: 81, easyString: 'q' };
  export const KEY_R: Key = { code: 'KeyR', keyCode: 82, easyString: 'r' };
  export const KEY_S: Key = { code: 'KeyS', keyCode: 83, easyString: 's' };
  export const KEY_T: Key = { code: 'KeyT', keyCode: 84, easyString: 't' };
  export const KEY_U: Key = { code: 'KeyU', keyCode: 85, easyString: 'u' };
  export const KEY_V: Key = { code: 'KeyV', keyCode: 86, easyString: 'v' };
  export const KEY_W: Key = { code: 'KeyW', keyCode: 87, easyString: 'w' };
  export const KEY_X: Key = { code: 'KeyX', keyCode: 88, easyString: 'x' };
  export const KEY_Y: Key = { code: 'KeyY', keyCode: 89, easyString: 'y' };
  export const KEY_Z: Key = { code: 'KeyZ', keyCode: 90, easyString: 'z' };

  export const MULTIPLY: Key = {
    code: 'NumpadMultiply',
    keyCode: 106,
    easyString: 'multiply',
  };
  export const ADD: Key = { code: 'NumpadAdd', keyCode: 107, easyString: 'add' };
  export const DECIMAL: Key = {
    code: 'NumpadDecimal',
    keyCode: 108,
    easyString: 'decimal',
  };
  export const SUBTRACT: Key = {
    code: 'NumpadSubtract',
    keyCode: 109,
    easyString: 'subtract',
  };
  export const DIVIDE: Key = {
    code: 'NumpadDivide',
    keyCode: 111,
    easyString: 'divide',
  };

  export const F1: Key = { code: 'F1', keyCode: 112, easyString: 'f1' };
  export const F2: Key = { code: 'F2', keyCode: 113, easyString: 'f2' };
  export const F3: Key = { code: 'F3', keyCode: 114, easyString: 'f3' };
  export const F4: Key = { code: 'F4', keyCode: 115, easyString: 'f4' };
  export const F5: Key = { code: 'F5', keyCode: 116, easyString: 'f5' };
  export const F6: Key = { code: 'F6', keyCode: 117, easyString: 'f6' };
  export const F7: Key = { code: 'F7', keyCode: 118, easyString: 'f7' };
  export const F8: Key = { code: 'F8', keyCode: 119, easyString: 'f8' };
  export const F9: Key = { code: 'F9', keyCode: 120, easyString: 'f9' };
  export const F10: Key = { code: 'F10', keyCode: 121, easyString: 'f10' };
  export const F11: Key = { code: 'F11', keyCode: 122, easyString: 'f11' };
  export const F12: Key = { code: 'F12', keyCode: 123, easyString: 'f12' };
  export const F13: Key = { code: 'F13', keyCode: 124, easyString: 'f13' };
  export const F14: Key = { code: 'F14', keyCode: 125, easyString: 'f14' };
  export const F15: Key = { code: 'F15', keyCode: 126, easyString: 'f15' };
  export const F16: Key = { code: 'F16', keyCode: 127, easyString: 'f16' };
  export const F17: Key = { code: 'F17', keyCode: 128, easyString: 'f17' };
  export const F18: Key = { code: 'F18', keyCode: 129, easyString: 'f18' };
  export const F19: Key = { code: 'F19', keyCode: 130, easyString: 'f19' };
  export const F20: Key = { code: 'F20', keyCode: 131, easyString: 'f20' };
  export const F21: Key = { code: 'F21', keyCode: 132, easyString: 'f21' };
  export const F22: Key = { code: 'F22', keyCode: 133, easyString: 'f22' };
  export const F23: Key = { code: 'F23', keyCode: 134, easyString: 'f23' };
  export const F24: Key = { code: 'F24', keyCode: 135, easyString: 'f24' };

  export const NUM_LOCK: Key = { code: 'NumLock', keyCode: 144, easyString: 'numlock' };
  export const SEMICOLON: Key = { code: 'Semicolon', keyCode: 186, easyString: ';' };
  export const EQUAL: Key = { code: 'Equal', keyCode: 187, easyString: '=' };
  export const COMMA: Key = { code: 'Comma', keyCode: 188, easyString: ',' };
  export const MINUS: Key = { code: 'Minus', keyCode: 189, easyString: '-' };
  export const PERIOD: Key = { code: 'Period', keyCode: 190, easyString: '.' };
  export const SLASH: Key = { code: 'Slash', keyCode: 191, easyString: '/' };
  export const BACKQUOTE: Key = { code: 'Backquote', keyCode: 192, easyString: '`' };
  export const INTL_RO: Key = { code: 'IntlRo', keyCode: 193, easyString: 'intlro' };
  export const BRACKET_LEFT: Key = {
    code: 'BracketLeft',
    keyCode: 219,
    easyString: '[',
  };
  export const BACKSLASH: Key = { code: 'Backslash', keyCode: 220, easyString: '\\' };
  export const BRACKET_RIGHT: Key = {
    code: 'BracketRight',
    keyCode: 221,
    easyString: ']',
  };
  export const QUOTE: Key = { code: 'Quote', keyCode: 222, easyString: "'" };
  export const INTL_BACKSLASH: Key = {
    code: 'IntlBackslash',
    keyCode: 229,
    easyString: 'intlbackslash',
  };
  export const INTL_YEN: Key = { code: 'IntlYen', keyCode: 255, easyString: 'intlyen' };

  export const MAX_KEY_CODE = INTL_YEN.keyCode;
}

/* -------------------- Initialize the static key mappings -------------------- */
(() => {
  // Set the default key mappings from the constants in the Key namespace
  Object.keys(Key)
    .map((prop) => Reflect.get(Key, prop))
    .filter((key) => Key.isKey(key))
    .forEach((key) => {
      CODE_TO_KEY[key.code] = key;
      KEY_CODE_TO_KEY[key.keyCode] = key;
      EASY_TO_KEY[key.easyString] = key;
    });

  // Set additional key mappings
  // Set additional key mappings
  CODE_TO_KEY['Numpad0'] = Key.DIGIT0;
  KEY_CODE_TO_KEY[96] = Key.DIGIT0;
  CODE_TO_KEY['Numpad1'] = Key.DIGIT1;
  KEY_CODE_TO_KEY[97] = Key.DIGIT1;
  CODE_TO_KEY['Numpad2'] = Key.DIGIT2;
  KEY_CODE_TO_KEY[98] = Key.DIGIT2;
  CODE_TO_KEY['Numpad3'] = Key.DIGIT3;
  KEY_CODE_TO_KEY[99] = Key.DIGIT3;
  CODE_TO_KEY['Numpad4'] = Key.DIGIT4;
  KEY_CODE_TO_KEY[100] = Key.DIGIT4;
  CODE_TO_KEY['Numpad5'] = Key.DIGIT5;
  KEY_CODE_TO_KEY[101] = Key.DIGIT5;
  CODE_TO_KEY['Numpad6'] = Key.DIGIT6;
  KEY_CODE_TO_KEY[102] = Key.DIGIT6;
  CODE_TO_KEY['Numpad7'] = Key.DIGIT7;
  KEY_CODE_TO_KEY[103] = Key.DIGIT7;
  CODE_TO_KEY['Numpad8'] = Key.DIGIT8;
  KEY_CODE_TO_KEY[104] = Key.DIGIT8;
  CODE_TO_KEY['Numpad9'] = Key.DIGIT9;
  KEY_CODE_TO_KEY[105] = Key.DIGIT9;
  CODE_TO_KEY['NumpadEnter'] = Key.ENTER;
  CODE_TO_KEY['NumpadEqual'] = Key.EQUAL;
  CODE_TO_KEY['MetaLeft'] = Key.OS_LEFT; // Chrome, Safari
  KEY_CODE_TO_KEY[224] = Key.OS_LEFT; // Firefox on Mac
  CODE_TO_KEY['MetaRight'] = Key.OS_RIGHT; // Chrome, Safari
  KEY_CODE_TO_KEY[93] = Key.OS_RIGHT; // Chrome, Safari, Edge
  KEY_CODE_TO_KEY[225] = Key.ALT_RIGHT; // Linux
  KEY_CODE_TO_KEY[110] = Key.DECIMAL; // Mac, Windows
  KEY_CODE_TO_KEY[59] = Key.SEMICOLON; // Firefox
  KEY_CODE_TO_KEY[61] = Key.EQUAL; // Firefox
  KEY_CODE_TO_KEY[173] = Key.MINUS; // Firefox
  KEY_CODE_TO_KEY[226] = Key.BACKSLASH; // Chrome, Edge on Windows
  KEY_CODE_TO_KEY[60] = Key.BACKSLASH; // Firefox on Linux

  // Set the modifier keys
  MODIFIERS.push(
    ...[
      Key.ALT_LEFT,
      Key.ALT_RIGHT,
      Key.CONTROL_LEFT,
      Key.CONTROL_RIGHT,
      Key.OS_LEFT,
      Key.OS_RIGHT,
      Key.SHIFT_LEFT,
      Key.SHIFT_RIGHT,
    ],
  );
})();

export type KeysOrKeyCodes = Key | KeyCode | (Key | KeyCode)[];
export namespace KeysOrKeyCodes {
  export const toKeyCode = (keyOrKeyCode: Key | KeyCode) =>
    keyOrKeyCode instanceof KeyCode
      ? keyOrKeyCode
      : KeyCode.createKeyCode({ first: keyOrKeyCode });

  export const toKeyCodes = (keysOrKeyCodes: KeysOrKeyCodes) => {
    if (keysOrKeyCodes instanceof KeyCode) {
      return [keysOrKeyCodes];
    }
    if (Array.isArray(keysOrKeyCodes)) {
      return keysOrKeyCodes.slice().map(toKeyCode);
    }
    return [toKeyCode(keysOrKeyCodes)];
  };
}