Function fetchWithFallbackProxies

website/src/pages/Explore.tsx:206–316

(
    url: string,
    onProgress?: (loaded: number, total: number) => void
  )

  
  // Helper to fetch files using a sequential pool of robust CORS proxies
  const fetchWithFallbackProxies = async (
    url: string,
    onProgress?: (loaded: number, total: number) => void
  ): Promise<Response> => {
    if (!url) throw new Error("URL is empty");
    
    // Try direct fetch first (essential for localhost, relative URLs, or CORS-enabled endpoints)
    try {
      const res = onProgress ? await fetchWithProgress(url, onProgress) : await fetch(url);
      if (res.ok) return res;
    } catch (e) {
      console.warn("Direct fetch failed, falling back to CORS proxies...", e);
    }
    
    // 1. Check raw githubusercontent.com to bypass proxy using jsDelivr CDN directly
    if (url.includes("raw.githubusercontent.com")) {
      const match = url.match(/raw\.githubusercontent\.com\/([^\/]+)\/([^\/]+)\/([^\/]+)\/(.+)$/);
      if (match) {
        const [_, ownerName, repoName, branch, filepath] = match;
        const jsdelivrUrl = `https://cdn.jsdelivr.net/gh/${ownerName}/${repoName}@${branch}/${filepath}`;
        try {
          const res = onProgress ? await fetchWithProgress(jsdelivrUrl, onProgress) : await fetch(jsdelivrUrl);
          if (res.ok) return res;
        } catch (e) {
          console.warn("jsDelivr CDN fetch failed, falling back to CORS proxies...", e);
        }
      }
    }

    const proxies = [
      // Proxy 1: corsproxy.io (Very fast, prefix-based)
      {
        url: (u: string) => `https://corsproxy.io/?${encodeURIComponent(u)}`,
        type: 'direct' as const
      },
      // Proxy 2: CodeTabs (Fast and supports redirects well)
      {
        url: (u: string) => `https://api.codetabs.com/v1/proxy?quest=${encodeURIComponent(u)}`,
        type: 'direct' as const
      },
      // Proxy 3: allorigins.win JSON endpoint (Handles S3 redirects perfectly via server-side base64 encoding!)
      {
        url: (u: string) => `https://api.allorigins.win/get?url=${encodeURIComponent(u)}`,
        type: 'json-base64' as const
      },
      // Proxy 4: allorigins.win raw (Alternative fallback)
      {
        url: (u: string) => `https://api.allorigins.win/raw?url=${encodeURIComponent(u)}`,
        type: 'direct' as const
      },
      // Proxy 5: thingproxy.freeboard.io (Fallback proxy)
      {
        url: (u: string) => `https://thingproxy.freeboard.io/fetch/${u}`,
        type: 'direct' as const
      }
    ];

    let lastError: any = null;