// UVerify plays nicely with any Cardano off-chain library.
// This example uses meshjs.dev

import { MeshWallet, KoiosProvider } from '@meshsdk/core';
import { sha256 } from 'js-sha256';
import axios from 'axios';

const BACKEND_URL = 'https://api.uverify.io'; // or 'http://localhost:9090' for local dev

// Generate a new wallet and store your mnemonic somewhere safe!
// If you lose it, you lose access to any funds held by this wallet.
const mnemonic = MeshWallet.brew();
console.log('Save your mnemonic:', mnemonic);

const koiosProvider = new KoiosProvider('api');
const wallet = new MeshWallet({
    networkId: 1, // 0: testnet, 1: mainnet
    fetcher: koiosProvider,
    submitter: koiosProvider,
    key: {
        type: 'mnemonic',
        words: mnemonic,
    },
});

const userAddress = await wallet.getChangeAddress();

// Hash the data you want to certify. This could be a string, file contents, etc.
const myData = 'Hello, UVerify!'; // replace with your content
const hash = sha256(myData);

// Optionally attach public metadata to the certificate
const metadata = {
    issuer: 'Acme Corp',
    description: 'Proof of existence for myData',
    date: new Date().toISOString(),
};

// Step 1: Build the unsigned transaction
// Make sure your wallet has funds before submitting a transaction.
// If you're on testnet, you can get free test ADA from the [Cardano Testnet Faucet](https://docs.cardano.org/cardano-testnets/tools/faucet/).
// If you're on mainnet, you'll need real ADA in your wallet. Your request will fail if the wallet balance is too low to cover the transaction fee.

const buildResponse = await axios.post(`${BACKEND_URL}/api/v1/transaction/build`, {
    type: 'DEFAULT',
    address: userAddress,
    certificates: [
        {
            hash,
            metadata,
            algorithm: 'SHA-256',
        },
    ],
});

if (buildResponse.status !== 200 || buildResponse.data.status?.code !== 'SUCCESS') {
    throw new Error('Failed to build transaction: ' + JSON.stringify(buildResponse.data));
}

// Step 2: Sign the transaction
const unsignedTx = buildResponse.data.unsigned_transaction;
const signedTx = await wallet.signTx(unsignedTx, true);

// Step 3: Submit the signed transaction
const submitResponse = await axios.post(`${BACKEND_URL}/api/v1/transaction/submit`, {
    transaction: signedTx,
});

if (submitResponse.status === 200 && submitResponse.data.successful) {
    console.log('Transaction submitted! TxHash:', submitResponse.data.value);
} else {
    throw new Error('Failed to submit transaction: ' + JSON.stringify(submitResponse.data));
}

const api = await window.cardano[enabledWallet].enable();
const userAddress = (await api.getUsedAddresses())[0];

// Build the transaction the same way as above...
const buildResponse = await axios.post(`${BACKEND_URL}/api/v1/transaction/build`, {
    type: 'DEFAULT',
    address: userAddress,
    certificates: [{ hash, metadata, algorithm: 'SHA-256' }],
});

const unsignedTx = buildResponse.data.unsigned_transaction;

// The user signs via their browser wallet — returns a witness set, not a full signed tx
const witnessSet = await api.signTx(unsignedTx, true);

const submitResponse = await axios.post(`${BACKEND_URL}/api/v1/transaction/submit`, {
    transaction: unsignedTx,
    witnessSet,
});

if (submitResponse.status === 200 && submitResponse.data.successful) {
    console.log('Transaction submitted! TxHash:', submitResponse.data.value);
}

  const metadata = {
      uverify_template_id: 'diploma',
      issuer: 'Acme University',
      recipient: 'Jane Doe',
  };