import { Injectable } from '@nestjs/common'
import { Prisma } from '../../../generated/prisma/client'
import { LedgerSourceType } from '../../../generated/prisma/enums'

@Injectable()
export class SupplierLedgerWorkflow {
  async updateLedgerBalance(
    tx: Prisma.TransactionClient,
    supplierId: number,
    amount: number,
    sourceId: number,
    sourceType: LedgerSourceType,
  ) {
    const lastSupplierLedgerBalance = await tx.supplierLedger
      .findFirstOrThrow({
        where: { supplierId },
        orderBy: { createdAt: 'desc' },
      })
      .then(sl => (sl ? sl.balance : 0))

    let newBalance = Number(lastSupplierLedgerBalance)
    let credit = 0
    let debit = 0
    let description = ''

    switch (sourceType) {
      case 'PURCHASE':
        newBalance += amount
        credit = amount
        description = `خرید به مبلغ ${amount} بابت خرید شماره ${sourceId}`
        break
      case 'REFUND':
      case 'PAYMENT':
        newBalance -= amount
        debit = amount
        description = `پرداخت به مبلغ ${amount} بابت پرداخت شماره ${sourceId}`
        break
      case 'ADJUSTMENT':
        newBalance = amount
        description = `اصلاح حساب به مبلغ ${amount} بابت پرداخت شماره ${sourceId}`

        break
    }

    return await tx.supplierLedger.create({
      data: {
        supplierId,
        debit,
        credit,
        balance: newBalance,
        sourceId,
        sourceType,
        description,
      },
    })
  }
}