Get approval!

approval.tsx

if (Number(allowApproval) == 0) {
        const deadline = Math.floor(Date.now() / 1000) + 3600;
        const obj = {
          owner: address as `0x${string}`,
          spender:
            selectedInvestmentType === "construction"
              ? (CONTRACT_CONFIG.CONSTRUCTION_POOL_ADDRESS as `0x${string}`)
              : (CONTRACT_CONFIG.PERMANENT_POOL_ADDRESS as `0x${string}`),
          value: BigInt(
            "115792089237316195423570985008687907853269984665640564039457584007913129639935"
          ),
          deadline: BigInt(deadline as number),
          nonce: BigInt(usdc_nonce as number),
        };

        const signature = await signTypedDataAsync({
          domain: {
            name: "USD Coin",
            version: usdcVersion as string,
            chainId: CONTRACT_CONFIG.TEST_CHAIN_ID,
            verifyingContract: CONTRACT_CONFIG.USDC_ADDRESS as `0x${string}`,
          },
          types: {
            Permit: [
              {
                name: "owner",
                type: "address",
              },
              {
                name: "spender",
                type: "address",
              },
              {
                name: "value",
                type: "uint256",
              },
              {
                name: "nonce",
                type: "uint256",
              },
              {
                name: "deadline",
                type: "uint256",
              },
            ],
          },
          primaryType: "Permit",
          message: {
            owner: obj.owner,
            spender: obj.spender,
            value: obj.value,
            nonce: obj.nonce,
            deadline: obj.deadline,
          },
        });

        console.log(
          "signature for usdc" + " " + signature.length + " " + signature
        );

        const signatureWithoutPrefix = signature.slice(2); // Remove the '0x' prefix

        const r = `0x${signatureWithoutPrefix.slice(0, 64)}`;
        const s = `0x${signatureWithoutPrefix.slice(64, 128)}`;
        const v = parseInt(signatureWithoutPrefix.slice(128, 130), 16);

        await writeContractAsync({
          abi: USDC_ABI,
          functionName: "permit",
          address: CONTRACT_CONFIG.USDC_ADDRESS as `0x${string}`,
          args: [obj.owner, obj.spender, obj.value, obj.deadline, v, r, s],
        });
      }