import { ToolAnnotations } from "@modelcontextprotocol/sdk/types.js";
import { getCurrentAccountKeys, getNetwork } from "../shared/account.js";
import { Contract, getDefaultProvider, Wallet } from "@coti-io/coti-ethers";
import { ERC721_ABI } from "../constants/abis.js";
import { z } from "zod";
export const APPROVE_PRIVATE_ERC721: ToolAnnotations = {
title: "Approve Private ERC721",
name: "approve_private_erc721",
description:
"Approve an address to transfer a specific private ERC721 NFT token on the COTI blockchain. " +
"This allows the approved address to transfer the specified NFT on behalf of the owner. " +
"Requires token contract address, token ID, and spender address as input. " +
"Returns the transaction hash upon successful approval.",
inputSchema: {
token_address: z.string().describe("ERC721 token contract address on COTI blockchain"),
token_id: z.string().describe("ID of the NFT token to approve for transfer"),
spender_address: z.string().describe("Address to approve as spender, e.g., 0x0D7C5C1DA069fd7C1fAFBeb922482B2C7B15D273"),
gas_limit: z.string().optional().describe("Optional gas limit for the transaction")
},
};
/**
* Checks if the provided arguments are valid for the approve_private_erc721 tool.
* @param args The arguments to validate
* @returns true if the arguments are valid, false otherwise
*/
export function isApprovePrivateERC721Args(
args: unknown
): args is { token_address: string; token_id: string; spender_address: string; gas_limit?: string } {
return (
typeof args === "object" &&
args !== null &&
"token_address" in args &&
typeof (args as { token_address: string }).token_address === "string" &&
"token_id" in args &&
typeof (args as { token_id: string }).token_id === "string" &&
"spender_address" in args &&
typeof (args as { spender_address: string }).spender_address === "string" &&
(!("gas_limit" in args) || typeof (args as { gas_limit?: string }).gas_limit === "string" || (args as { gas_limit?: string }).gas_limit === undefined)
);
}
/**
* Handler for the approvePrivateERC721 tool
* @param args The arguments for the tool
* @returns The tool response
*/
export async function approvePrivateERC721Handler(args: Record<string, unknown> | undefined): Promise<any> {
if (!isApprovePrivateERC721Args(args)) {
throw new Error("Invalid arguments for approve_private_erc721");
}
const { token_address, token_id, spender_address, gas_limit } = args;
const results = await performApprovePrivateERC721(token_address, token_id, spender_address, gas_limit);
return {
content: [{ type: "text", text: results }],
isError: false,
};
}
/**
* Approves an address to transfer a specific private ERC721 NFT token
* @param token_address The address of the ERC721 token contract
* @param token_id The ID of the token to approve for transfer
* @param spender_address The address to approve as spender
* @param gas_limit Optional gas limit for the transaction
* @returns A formatted string with the transaction information
*/
export async function performApprovePrivateERC721(
token_address: string,
token_id: string,
spender_address: string,
gas_limit?: string
): Promise<any> {
try {
const provider = getDefaultProvider(getNetwork());
const currentAccountKeys = getCurrentAccountKeys();
const wallet = new Wallet(currentAccountKeys.privateKey, provider);
wallet.setAesKey(currentAccountKeys.aesKey);
const tokenContract = new Contract(token_address, ERC721_ABI, wallet);
const name = await tokenContract.name();
const symbol = await tokenContract.symbol();
// Check if the current account is the owner of the token
const owner = await tokenContract.ownerOf(token_id);
if (owner.toLowerCase() !== wallet.address.toLowerCase()) {
throw new Error(`You are not the owner of token ID ${token_id}. The owner is ${owner}.`);
}
// Prepare transaction options
const options: { gasLimit?: number } = {};
if (gas_limit) {
options.gasLimit = parseInt(gas_limit);
}
// Execute the approve transaction
const tx = await tokenContract.approve(spender_address, token_id, options);
const receipt = await tx.wait();
return `Successfully approved ${spender_address} to transfer NFT token ID ${token_id} from ${name} (${symbol}).\nTransaction hash: ${receipt.hash}`;
} catch (error) {
console.error('Error approving private ERC721 token transfer:', error);
throw new Error(`Failed to approve private ERC721 token transfer: ${error instanceof Error ? error.message : String(error)}`);
}
}
