import * as _ from 'lodash';
import {ContractWrapper} from './contract_wrapper';
import * as TokenTransferProxyArtifacts from '../artifacts/TokenTransferProxy.json';
import {TokenTransferProxyContract} from '../types';

/**
 * This class includes the functionality related to interacting with the TokenTransferProxy contract.
 */
export class TokenTransferProxyWrapper extends ContractWrapper {
    private _tokenTransferProxyContractIfExists?: TokenTransferProxyContract;
    /**
     * Check if the Exchange contract address is authorized by the TokenTransferProxy contract.
     * @param   exchangeContractAddress     The hex encoded address of the Exchange contract to call.
     * @return  Whether the exchangeContractAddress is authorized.
     */
    public async isAuthorizedAsync(exchangeContractAddress: string): Promise<boolean> {
        const tokenTransferProxyContractInstance = await this._getTokenTransferProxyContractAsync();
        const isAuthorized = await tokenTransferProxyContractInstance.authorized.call(exchangeContractAddress);
        return isAuthorized;
    }
    /**
     * Get the list of all Exchange contract addresses authorized by the TokenTransferProxy contract.
     * @return  The list of authorized addresses.
     */
    public async getAuthorizedAddressesAsync(): Promise<string[]> {
        const tokenTransferProxyContractInstance = await this._getTokenTransferProxyContractAsync();
        const authorizedAddresses = await tokenTransferProxyContractInstance.getAuthorizedAddresses.call();
        return authorizedAddresses;
    }
    private _invalidateContractInstance(): void {
        delete this._tokenTransferProxyContractIfExists;
    }
    private async _getTokenTransferProxyContractAsync(): Promise<TokenTransferProxyContract> {
        if (!_.isUndefined(this._tokenTransferProxyContractIfExists)) {
            return this._tokenTransferProxyContractIfExists;
        }
        const contractInstance = await this._instantiateContractIfExistsAsync((TokenTransferProxyArtifacts as any));
        this._tokenTransferProxyContractIfExists = contractInstance as TokenTransferProxyContract;
        return this._tokenTransferProxyContractIfExists;
    }
}