import { Injectable, UnprocessableEntityException } from '@nestjs/common';
import { CreateApplicationResponse } from '~/common/modules/neoleap/dtos/response';
import { Account } from '../entities/account.entity';
import { AccountRepository } from '../repositories/account.repository';

@Injectable()
export class AccountService {
  constructor(private readonly accountRepository: AccountRepository) {}

  createAccount(data: CreateApplicationResponse): Promise<Account> {
    return this.accountRepository.createAccount(data);
  }

  async getAccountByReferenceNumber(accountReference: string): Promise<Account> {
    const account = await this.accountRepository.getAccountByReferenceNumber(accountReference);
    if (!account) {
      throw new UnprocessableEntityException('ACCOUNT.NOT_FOUND');
    }
    return account;
  }

  async getAccountByAccountNumber(accountNumber: string): Promise<Account> {
    const account = await this.accountRepository.getAccountByAccountNumber(accountNumber);
    if (!account) {
      throw new UnprocessableEntityException('ACCOUNT.NOT_FOUND');
    }
    return account;
  }

  async getAccountByIban(iban: string): Promise<Account> {
    const account = await this.accountRepository.getAccountByIban(iban);
    if (!account) {
      throw new UnprocessableEntityException('ACCOUNT.NOT_FOUND');
    }
    return account;
  }

  creditAccountBalance(accountReference: string, amount: number) {
    return this.accountRepository.topUpAccountBalance(accountReference, amount);
  }

  async getAccountByCustomerId(customerId: string): Promise<Account> {
    const account = await this.accountRepository.getAccountByCustomerId(customerId);
    if (!account) {
      throw new UnprocessableEntityException('ACCOUNT.NOT_FOUND');
    }
    return account;
  }

  async decreaseAccountBalance(accountReference: string, amount: number) {
    const account = await this.getAccountByReferenceNumber(accountReference);

    /**
     *
     * While there is no need to check for insufficient balance  because this is a webhook handler,
     * I just added this check to ensure we don't have corruption in our data.
     */

    if (account.balance < amount) {
      throw new UnprocessableEntityException('ACCOUNT.INSUFFICIENT_BALANCE');
    }

    return this.accountRepository.decreaseAccountBalance(accountReference, amount);
  }

  increaseReservedBalance(account: Account, amount: number) {
    // Balance check is performed by the caller (e.g., transferToChild)
    // to ensure correct account (guardian vs child) is validated
    return this.accountRepository.increaseReservedBalance(account.id, amount);
  }

  decrementReservedBalance(account: Account, amount: number) {
    return this.accountRepository.decreaseReservedBalance(account.id, amount);
  }

  //THIS IS A MOCK FUNCTION FOR TESTING PURPOSES ONLY
  async fundIban(iban: string, amount: number) {
    const account = await this.getAccountByIban(iban);
    return this.accountRepository.topUpAccountBalance(account.accountReference, amount);
  }
}