Error Handling

import {
  ActionPostRequest,
  ActionPostResponse,
  ActionError,
  ACTIONS_CORS_HEADERS,
} from "@solana/actions";
import { PublicKey } from "@solana/web3.js";

// Other code, such as headers, GET and OPTIONS request, etc. 

export const POST = async (req: Request) => {
  try {
    const url = new URL(req.url);
    const amount = Number(url.searchParams.get("amount"));
    
    // Validate donation amount
    if (!amount || isNaN(amount)) {
      throw new Error("Please enter a valid donation amount");
    }
    
    if (amount < 0.05) {
      throw new Error("Minimum donation is 0.05 SOL");
    }
    
    if (amount > 10) {
      throw new Error("Maximum donation is 10 SOL per transaction");
    }
    
    const request: ActionPostRequest = await req.json();
    
    // Nested validation example: Validate wallet address
    let payer: PublicKey;
    try {
      payer = new PublicKey(request.account);
    } catch {
      throw new Error("Invalid wallet address format");
    }
    
    // Process transaction (simplified for example)
    const transaction = await prepareTransaction(
      connection,
      payer,
      receiver,
      amount
    );
    
    const response: ActionPostResponse = {
      type: "transaction",
      transaction: Buffer.from(transaction.serialize()).toString("base64"),
    };
    
    return Response.json(response, {
      status: 200,
      headers
    });
    
  } catch (error) {
    console.error("Donation error:", error);
    
    // Return ActionError for Blink UI display
    const errorResponse: ActionError = {
      message: error instanceof Error ? error.message : "Internal server error"
    };
    
    return new Response(JSON.stringify(errorResponse), {
      status: 500,
      headers
    });
  }
};

// prepareTransaction function ...