BetterSEQTA-Plus/src/seqta/ui/themes/downloadTheme.ts

import localforage from 'localforage';
import base64ToBlob from '@/seqta/utils/base64ToBlob';

type Theme = {
  name: string;
  description: string;
  coverImage: string;
  marqueeImage: string;
  id: string;
}

type ThemeContent = {
  id: string;
  name: string;
  coverImage: string; // base64
  description: string;
  defaultColour: string;
  CanChangeColour: boolean;
  CustomCSS: string;
  hideThemeName: boolean;
  images: { id: string, variableName: string, data: string }[]; // data: base64
};

function stripBase64Prefix(base64String: string): string {
  const prefixRegex = /^data:image\/\w+;base64,/;
  return base64String.replace(prefixRegex, '');
}

export const StoreDownloadTheme = async (theme: { themeContent: Theme }) => {
  if (!theme.themeContent.id) return;

  const themeContent = await fetch(`https://raw.githubusercontent.com/BetterSEQTA/BetterSEQTA-Themes/main/store/themes/${theme.themeContent.id}/theme.json`);
  const themeData = await themeContent.json() as ThemeContent;

  await InstallTheme(themeData);
};

export const InstallTheme = async (themeData: ThemeContent) => {
  const strippedCoverImage = stripBase64Prefix(themeData.coverImage);
  const coverImageBlob = base64ToBlob(strippedCoverImage);

  const images = themeData.images.map((image) => ({
    ...image,
    blob: base64ToBlob(image.data)
  }));

  let availableThemes = await localforage.getItem('customThemes') as string[];
  if (availableThemes && !availableThemes.includes(themeData.id)) {
    availableThemes.push(themeData.id);
  } else if (!availableThemes) {
    availableThemes = [themeData.id];
  }
  await localforage.setItem('customThemes', availableThemes);

  await localforage.setItem(themeData.id, {
    ...themeData,
    webURL: themeData.id,
    coverImage: coverImageBlob,
    CustomImages: themeData.images.map((image) => {
      return {
        ...image,
        blob: images.find((img) => image.id === img.id)?.blob
      };
    })
  });
};