import { Address, erc20Abi, isAddressEqual, maxUint256 } from 'viem';
import { Permit, PERMIT2_MAP } from '@prex0/prex-structs';
import { PrexUser } from '../types';
import { PrexSigner } from '../core/sign';
import { PrexApiService } from '../api';
import { PrexClient } from '../prex-client';
import { getTokenName } from '../evm-api/token-detail';

const AN_HOUR_IN_SECONDS = 60 * 60;

export class ApproveAction {
  constructor(
    private client: PrexClient,
    private user: PrexUser,
    private signer: PrexSigner,
    private apiService: PrexApiService
  ) {}

  async approve({
    token,
    amount = maxUint256,
    from,
  }: {
    token: Address;
    amount?: bigint;
    from?: Address;
  }) {
    if (this.user.walletId === '') {
      // Use permit if it is not a smart wallet
      const name = await getTokenName(this.client.evmChainClient, token);

      const deadline = getDeadline();

      const permit = new Permit(
        {
          owner: this.user.address,
          spender: PERMIT2_MAP[this.apiService.chainId],
          value: amount,
          nonce: await this.client.updatePermitNonce(token),
          deadline,
        },
        name,
        getVersion(token),
        this.apiService.chainId,
        token
      );

      const { domain, types, message } = permit.permitData();

      const signature = await this.signer.signTypedData({
        domain,
        types,
        message,
        primaryType: 'Permit',
      });

      await this.apiService.permit({
        owner: message.owner,
        spender: message.spender,
        value: message.value.toString(),
        deadline: message.deadline.toString(),
        signature,
        address: token,
      });
    } else {
      await this.client.executeOperation(
        {
          address: token,
          abi: erc20Abi,
          functionName: 'approve',
          args: [PERMIT2_MAP[this.apiService.chainId], amount],
        },
        from
      );
    }

    await this.client.fetchBalance(token);
  }
}

function getVersion(address: Address) {
  // Native USDC in Arbitrum
  if (isAddressEqual(address, '0xaf88d065e77c8cc2239327c5edb3a432268e5831')) {
    return '2';
  }

  return '1';
}

function getDeadline() {
  return BigInt(Math.floor(Date.now() / 1000 + AN_HOUR_IN_SECONDS));
}