import type { EasingType } from '../types/cutscene';

export const EASING_OPTIONS: EasingType[] = [
  'Linear',
  'EaseInSine', 'EaseOutSine', 'EaseInOutSine',
  'EaseInQuad', 'EaseOutQuad', 'EaseInOutQuad',
  'EaseInCubic', 'EaseOutCubic', 'EaseInOutCubic',
];

export function applyEasing(t: number, easing: EasingType): number {
  const pi = Math.PI;
  switch (easing) {
    case 'Linear':        return t;
    case 'EaseInSine':    return 1 - Math.cos((t * pi) / 2);
    case 'EaseOutSine':   return Math.sin((t * pi) / 2);
    case 'EaseInOutSine': return -(Math.cos(pi * t) - 1) / 2;
    case 'EaseInQuad':    return t * t;
    case 'EaseOutQuad':   return 1 - (1 - t) * (1 - t);
    case 'EaseInOutQuad': return t < 0.5 ? 2 * t * t : 1 - Math.pow(-2 * t + 2, 2) / 2;
    case 'EaseInCubic':   return t * t * t;
    case 'EaseOutCubic':  return 1 - Math.pow(1 - t, 3);
    case 'EaseInOutCubic':return t < 0.5 ? 4 * t * t * t : 1 - Math.pow(-2 * t + 2, 3) / 2;
    default:              return t;
  }
}