import * as opentype from 'opentype.js';
import { TypographySettings } from './AttributedString';

class FontStorage {
  private fonts: Record<string, () => opentype.Font>;
  private cache: Record<string, opentype.Font> = {};

  constructor() {
    this.fonts = {};
  }

  public getFont(settings: TypographySettings): opentype.Font {
    const style =
      settings.fontStyle === 'italic'
        ? settings.fontStyle
        : settings.fontWeight;
    const name = `${settings.fontFamily}${
      style ? '-' + style[0].toUpperCase() + style.slice(1) : ''
    }`;
    if (name in this.fonts) {
      if (name in this.cache) {
        return this.cache[name];
      }
      this.cache[name] = this.fonts[name]();
      return this.cache[name];
    } else {
      throw new Error(`Could not find font with name: ${name}`);
    }
  }

  public registerFont(name: string, font: () => opentype.Font): boolean {
    if (name in this.fonts) {
      throw new Error(`Font ${name} already registered`);
    }
    this.fonts[name] = font;
    return true;
  }
}

export default new FontStorage();