copilotkit__copilotkit/docs/middleware.ts

import { NextResponse } from "next/server";
import type { NextRequest } from "next/server";

export function middleware(request: NextRequest) {
  const { pathname } = request.nextUrl;

  // Common redirects for broken links
  const redirects: Record<string, string> = {
    // Old coagents paths
    "/coagents": "/langgraph",
    "/coagents/quickstart": "/langgraph/quickstart",
    "/coagents/guides": "/langgraph/guides",
    "/coagents/shared-state": "/langgraph/shared-state",
    "/coagents/human-in-the-loop": "/langgraph/human-in-the-loop",
    "/coagents/multi-agent-flows": "/langgraph/multi-agent-flows",
    "/coagents/persistence": "/langgraph/persistence",
    "/coagents/advanced": "/langgraph/advanced",
    "/coagents/videos": "/langgraph/videos",
    "/coagents/tutorials": "/langgraph/tutorials",
    "/coagents/concepts": "/langgraph/concepts",
    "/coagents/frontend-actions": "/langgraph/frontend-actions",
    "/coagents/generative-ui": "/langgraph/generative-ui",

    // Common typos and variations
    "/direct-to-llm/guide": "/direct-to-llm/guides",
    "/langgraph/guide": "/langgraph/guides",
    "/mastra/guide": "/mastra/guides",
    "/agno/guide": "/agno/guides",
    "/llamaindex/guide": "/llamaindex/guides",
    "/crewai-crews/guide": "/crewai-crews/guides",
    "/crewai-flows/guide": "/crewai-flows/guides",
    "/ag2/guide": "/ag2/guides",
    "/pydantic-ai/guide": "/pydantic-ai/guides",
    "/adk/guide": "/adk/guides",

    // API reference variations
    "/api": "/reference",
    "/docs/api": "/reference",
    "/api-reference": "/reference",

    // Quickstart variations
    "/quickstart": "/direct-to-llm/guides/quickstart",
    "/getting-started": "/direct-to-llm/guides/quickstart",
    "/start": "/direct-to-llm/guides/quickstart",

    // Frontend tools variations
    "/frontend-tools": "/direct-to-llm/guides/frontend-actions",
    "/frontend-actions": "/direct-to-llm/guides/frontend-actions",

    // Contributing paths
    "/contributing/code-contributions/package-linking":
      "/shared/contributing/code-contributions/package-linking",
  };

  // Check for exact matches
  if (redirects[pathname]) {
    return NextResponse.redirect(new URL(redirects[pathname], request.url));
  }

  // Check for pattern-based redirects
  if (pathname.startsWith("/coagents/")) {
    const newPath = pathname.replace("/coagents/", "/langgraph/");
    return NextResponse.redirect(new URL(newPath, request.url));
  }

  // Handle guide -> guides redirects
  if (pathname.includes("/guide") && !pathname.includes("/guides")) {
    const newPath = pathname.replace("/guide", "/guides");
    return NextResponse.redirect(new URL(newPath, request.url));
  }

  // Handle quickstart redirects for specific frameworks
  if (pathname === "/quickstart") {
    return NextResponse.redirect(
      new URL("/direct-to-llm/guides/quickstart", request.url),
    );
  }

  // Check for partial matches and suggest alternatives
  const suggestions = generateSuggestions(pathname);

  if (suggestions.length > 0) {
    // For now, we'll let the 404 page handle suggestions
    // In the future, we could redirect to a special 404 page with suggestions
  }

  return NextResponse.next();
}

function generateSuggestions(pathname: string): string[] {
  const suggestions: string[] = [];

  // Common patterns that might be typos
  if (pathname.includes("guide") && !pathname.includes("guides")) {
    suggestions.push(pathname.replace("guide", "guides"));
  }

  if (pathname.includes("coagents")) {
    suggestions.push(pathname.replace("coagents", "langgraph"));
  }

  if (pathname.includes("/api") && !pathname.includes("/reference")) {
    suggestions.push("/reference");
  }

  return suggestions;
}

export const config = {
  matcher: [
    /*
     * Match all request paths except for the ones starting with:
     * - api (API routes)
     * - _next/static (static files)
     * - _next/image (image optimization files)
     * - favicon.ico (favicon file)
     */
    "/((?!api|_next/static|_next/image|favicon.ico).*)",
  ],
};