import { QUERY_CONSTANTS } from '@/common/queryConstants'
import { SalesInvoiceCreateInput } from '@/generated/prisma/models'
import { PrismaService } from '@/prisma/prisma.service'
import { BadRequestException, Injectable } from '@nestjs/common'
import { Prisma } from 'generated/prisma/client'
import {
  CustomerType,
  PaymentMethodType,
  TspProviderRequestType,
} from 'generated/prisma/enums'
import { SharedCreateSalesInvoiceDto } from './sale-invoice-create.dto'

interface TerminalPaymentInfo {
  terminal_id: string
  stan: string
  rrn: string
  transaction_date_time: string | Date
  customer_card_no: string
  description?: string
  amount: number
}

interface NormalizedPayment {
  method: PaymentMethodType
  amount: number
}

interface CreateSharedSaleInvoiceInput {
  tx?: Prisma.TransactionClient
  data: SharedCreateSalesInvoiceDto
  businessId: string
  complexId: string
  posId: string
  consumerAccountId: string
  type: TspProviderRequestType
  main_invoice_id?: string
  ref_invoice_id?: string
}

@Injectable()
export class SharedSaleInvoiceCreateService {
  private readonly createInvoiceRetries = 3

  constructor(private prisma: PrismaService) {}

  async create(input: CreateSharedSaleInvoiceInput) {
    const {
      tx = this.prisma,
      data,
      businessId,
      complexId,
      posId,
      consumerAccountId,
      type,
      main_invoice_id,
      ref_invoice_id,
    } = input

    const normalizedInvoiceDate = this.normalizeInvoiceDate(data.invoice_date)
    const { payments, terminalInfo } = this.buildPaymentsData(
      data.payments,
      data.total_amount,
    )

    for (let attempt = 1; attempt <= this.createInvoiceRetries; attempt++) {
      try {
        return await tx.$transaction(async $tx => {
          const invoiceNumber = await this.getNextInvoiceNumber($tx, businessId)
          const customerId = await this.resolveCustomerId($tx, data, businessId)
          const goodsById = await this.getGoodsById($tx, data)
          const salesInvoiceData = this.buildSalesInvoiceData({
            data,
            normalizedInvoiceDate,
            invoiceNumber,
            consumerAccountId,
            businessId,
            complexId,
            posId,
            goodsById,
            customerId,
            type,
            main_invoice_id,
            ref_invoice_id,
          })

          const salesInvoice = await $tx.salesInvoice.create({
            data: salesInvoiceData,
            select: { ...QUERY_CONSTANTS.SALE_INVOICE.select },
          })

          await this.createPayments(
            $tx,
            salesInvoice.id,
            payments,
            terminalInfo,
            normalizedInvoiceDate,
          )

          return salesInvoice
        })
      } catch (error) {
        if (
          this.isRetryableInvoiceConflict(error) &&
          attempt < this.createInvoiceRetries
        ) {
          continue
        }
        throw error
      }
    }

    throw new BadRequestException('ایجاد فاکتور با خطا مواجه شد.')
  }

  private isRetryableInvoiceConflict(error: unknown) {
    if (!(error instanceof Prisma.PrismaClientKnownRequestError)) {
      return false
    }

    if (error.code !== 'P2002') {
      return false
    }

    const target = (error.meta?.target as string[]) || []
    return (
      target.includes('invoice_number') ||
      target.includes('sales_invoices_invoice_number_pos_id_key')
    )
  }

  private normalizeInvoiceDate(invoiceDate: Date | string) {
    return new Date(invoiceDate).toISOString() as any
  }

  private buildPaymentsData(
    paymentsData: SharedCreateSalesInvoiceDto['payments'],
    totalAmount: number,
  ) {
    const paymentMethodMap: Record<string, PaymentMethodType> = {
      cash: PaymentMethodType.CASH,
      set_off: PaymentMethodType.SET_OFF,
      card: PaymentMethodType.CARD,
      payment_gateway: PaymentMethodType.PAYMENT_GATEWAY,
      bank: PaymentMethodType.BANK,
      check: PaymentMethodType.CHEQUE,
      other: PaymentMethodType.OTHER,
      terminal: PaymentMethodType.TERMINAL,
    }

    const rawPayments = (paymentsData || {}) as Record<string, unknown>
    const terminalInfo = rawPayments.terminals as TerminalPaymentInfo | undefined

    const payments: NormalizedPayment[] = Object.entries(rawPayments)
      .filter(([key, value]) => key !== 'terminals' && value && Number(value) > 0)
      .map(([key, value]) => ({
        method: paymentMethodMap[key.toLowerCase()],
        amount: typeof value === 'number' ? value : Number(value || 0),
      }))
      .filter(payment => payment.method && payment.amount > 0) as NormalizedPayment[]

    const hasTerminalPayment = payments.some(
      payment => payment.method === PaymentMethodType.TERMINAL,
    )
    const nonTerminalTotal = payments
      .filter(payment => payment.method !== PaymentMethodType.TERMINAL)
      .reduce((sum, payment) => sum + payment.amount, 0)

    if (!hasTerminalPayment && terminalInfo) {
      const terminalAmount =
        typeof terminalInfo.amount === 'number'
          ? terminalInfo.amount
          : Math.max(0, Number(totalAmount) - nonTerminalTotal)

      if (terminalAmount > 0) {
        payments.push({
          method: PaymentMethodType.TERMINAL,
          amount: terminalAmount,
        })
      }
    }

    this.validatePayments(payments, totalAmount, terminalInfo)

    return {
      payments,
      terminalInfo,
    }
  }

  private validatePayments(
    payments: NormalizedPayment[],
    totalAmount: number,
    terminalInfo?: TerminalPaymentInfo,
  ) {
    const totalPayments = payments.reduce((sum, payment) => sum + payment.amount, 0)
    const roundedTotalPayments = Number(totalPayments.toFixed(2))
    const roundedTotalAmount = Number(Number(totalAmount).toFixed(2))

    if (roundedTotalPayments !== roundedTotalAmount) {
      throw new BadRequestException('مبلغ پرداختی باید برابر با مبلغ کل فاکتور باشد.')
    }

    const terminalPayments = payments.filter(
      payment => payment.method === PaymentMethodType.TERMINAL,
    )

    if (terminalPayments.length > 0 && !terminalInfo) {
      throw new BadRequestException('برای پرداخت ترمینال اطلاعات ترمینال الزامی است.')
    }
  }

  private async resolveCustomerId(
    tx: Prisma.TransactionClient,
    data: SharedCreateSalesInvoiceDto,
    businessId: string,
  ) {
    if (data.customer_id) {
      return data.customer_id
    }

    if (
      data.customer_type === CustomerType.INDIVIDUAL &&
      data.customer?.customer_individual
    ) {
      const { national_id, mobile_number, ...rest } = data.customer.customer_individual

      const customerIndividual = await tx.customerIndividual.upsert({
        where: {
          business_activity_id_national_id: {
            business_activity_id: businessId,
            national_id: data.customer.customer_individual.national_id,
          },
        },
        create: {
          ...data.customer.customer_individual,
          customer: {
            create: {
              type: CustomerType.INDIVIDUAL,
            },
          },
          business_activity: {
            connect: {
              id: businessId,
            },
          },
        },
        update: { ...rest },
        select: {
          customer_id: true,
        },
      })

      if (!customerIndividual) {
        throw new BadRequestException('متاسفانه مشکلی در اطلاعات مشتری وجود دارد.')
      }

      return customerIndividual.customer_id
    }

    if (data.customer_type === CustomerType.LEGAL && data.customer?.customer_legal) {
      const { registration_number, ...rest } = data.customer.customer_legal
      const customerLegal = await tx.customerLegal.upsert({
        where: {
          business_activity_id_economic_code: {
            business_activity_id: businessId,
            economic_code: data.customer.customer_legal.economic_code,
          },
        },
        create: {
          ...data.customer.customer_legal,
          customer: {
            create: {
              type: CustomerType.LEGAL,
            },
          },
          business_activity: {
            connect: {
              id: businessId,
            },
          },
        },
        update: {
          ...rest,
        },
        select: {
          customer_id: true,
        },
      })

      if (!customerLegal) {
        throw new BadRequestException('متاسفانه مشکلی در اطلاعات مشتری وجود دارد.')
      }

      return customerLegal.customer_id
    }

    return null
  }

  private async getGoodsById(
    tx: Prisma.TransactionClient,
    data: SharedCreateSalesInvoiceDto,
  ) {
    const itemGoodIds = data.items
      .map(item => item.good_id)
      .filter((goodId): goodId is string => Boolean(goodId))

    const goods = itemGoodIds.length
      ? await tx.good.findMany({
          where: {
            id: {
              in: itemGoodIds,
            },
          },
          select: {
            id: true,
            name: true,
            sku: {
              select: {
                id: true,
                name: true,
                code: true,
                VAT: true,
              },
            },
            local_sku: true,
            barcode: true,
            pricing_model: true,
            measure_unit: {
              select: {
                id: true,
                name: true,
                code: true,
              },
            },
            base_sale_price: true,
            image_url: true,
            category: {
              select: {
                id: true,
                name: true,
              },
            },
          },
        })
      : []

    return new Map(goods.map(good => [good.id, good]))
  }

  private buildSalesInvoiceData(params: {
    data: SharedCreateSalesInvoiceDto
    normalizedInvoiceDate: Date
    invoiceNumber: number
    consumerAccountId: string
    businessId: string
    complexId: string
    posId: string
    goodsById: Map<string, any>
    customerId: string | null
    type: TspProviderRequestType
    main_invoice_id?: string
    ref_invoice_id?: string
  }) {
    const {
      data,
      normalizedInvoiceDate,
      invoiceNumber,
      consumerAccountId,
      posId,
      goodsById,
      customerId,
      businessId,
      complexId,
      type,
      main_invoice_id,
      ref_invoice_id,
    } = params
    const {
      customer_id,
      customer_type,
      customer,
      payments,
      settlement_type,
      ...invoiceData
    } = data

    if (
      type !== TspProviderRequestType.ORIGINAL &&
      !(main_invoice_id || ref_invoice_id)
    ) {
      throw new BadRequestException('متاسفانه مشکلی در اطلاعات فاکتور وجود دارد.')
    }

    const salesInvoiceData: SalesInvoiceCreateInput = {
      ...invoiceData,
      invoice_date: normalizedInvoiceDate,
      invoice_number: invoiceNumber,
      total_amount: data.total_amount,
      discount_amount: data.items.reduce(
        (prev, curr) => (prev += curr.discount_amount),
        0,
      ),
      tax_amount: data.items.reduce((prev, curr) => (prev += curr.tax_amount), 0),
      code: this.generateInvoiceCode(businessId, complexId, posId, invoiceNumber),
      type,
      settlement_type,
      items: {
        createMany: {
          data: data.items.map(item => ({
            good_id: item.good_id!,
            quantity: item.quantity,
            unit_price: item.unit_price,
            total_amount: item.total_amount,
            discount_amount: item.discount_amount,
            tax_amount: item.tax_amount,
            measure_unit_text: goodsById.get(item.good_id!)?.measure_unit.name || null,
            measure_unit_code: goodsById.get(item.good_id!)?.measure_unit.code || null,
            sku_code: goodsById.get(item.good_id!)?.sku.code || null,
            sku_vat: goodsById.get(item.good_id!)?.sku.VAT || null,
            payload: item.payload ? JSON.parse(JSON.stringify(item.payload)) : undefined,
            good_snapshot: item.good_id
              ? JSON.parse(JSON.stringify(goodsById.get(item.good_id) || null))
              : undefined,
          })),
        },
      },
      unknown_customer: {},
      consumer_account: {
        connect: {
          id: consumerAccountId,
        },
      },
      pos: {
        connect: {
          id: posId,
        },
      },
    }

    if (customerId) {
      salesInvoiceData.customer = {
        connect: {
          id: customerId,
        },
      }
    }

    if (type !== TspProviderRequestType.ORIGINAL) {
      salesInvoiceData.main_id = main_invoice_id
      salesInvoiceData.reference_invoice = {
        connect: {
          id: ref_invoice_id,
        },
      }
    }

    return salesInvoiceData
  }

  private async getNextInvoiceNumber(tx: Prisma.TransactionClient, businessId: string) {
    const latestInvoice = await tx.salesInvoice.findFirst({
      where: {
        pos: {
          complex: {
            business_activity_id: businessId,
          },
        },
      },
      orderBy: {
        invoice_number: 'desc',
      },
      select: {
        invoice_number: true,
        pos: {
          select: {
            complex: {
              select: {
                business_activity: {
                  select: {
                    invoice_number_sequence: true,
                  },
                },
              },
            },
          },
        },
      },
    })

    const latestSequence =
      latestInvoice?.pos?.complex?.business_activity?.invoice_number_sequence.toNumber() ||
      0

    return Math.max(latestInvoice?.invoice_number || 0, latestSequence) + 1
  }

  private async createPayments(
    tx: Prisma.TransactionClient,
    invoiceId: string,
    payments: NormalizedPayment[],
    terminalInfo: TerminalPaymentInfo | undefined,
    paidAt: Date,
  ) {
    for (const payment of payments) {
      if (payment.amount <= 0) {
        continue
      }
      const createdPayment = await tx.salesInvoicePayment.create({
        data: {
          invoice_id: invoiceId,
          amount: payment.amount,
          payment_method: payment.method,
          paid_at: paidAt,
        },
      })

      if (payment.method === PaymentMethodType.TERMINAL && terminalInfo) {
        await tx.salesInvoicePaymentTerminalInfo.create({
          data: {
            payment_id: createdPayment.id,
            terminal_id: terminalInfo.terminal_id,
            stan: terminalInfo.stan,
            rrn: terminalInfo.rrn,
            transaction_date_time: new Date(terminalInfo.transaction_date_time || ''),
            customer_card_no: terminalInfo.customer_card_no || null,
            description: terminalInfo.description || null,
          },
        })
      }
    }
  }

  private generateInvoiceCode(
    businessId: string,
    complexId: string,
    posId: string,
    invoiceNumber: number,
  ) {
    return `${businessId.substring(businessId.length - 2, businessId.length)}${complexId.substring(complexId.length - 2, complexId.length)}${posId.substring(posId.length - 2, posId.length)}${invoiceNumber.toString()}`
  }
}