sx-fc/app/models/sale_payment.rb

class SalePayment < ApplicationRecord
  self.primary_key = "sale_payment_id"

  #primary key - need to be unique generated for multiple shops
  before_create :generate_custom_id

  belongs_to :sale

  attr_accessor :received_amount, :card_payment_reference, :voucher_no, :giftcard_no, :customer_id, :external_payment_status

  def process_payment(invoice, action_by, cash_amount)

    self.sale = invoice
    self.received_amount = cash_amount
    
    payment_method = "cash"
    amount_due = invoice.grand_total

    #get all payment for this invoices
    invoice.sale_payments.each do |payment|
      if (payment.payment_status == "paid" )
        amount_due = amount_due - payment.payment_amount
      end
    end

    if (amount_due > 0)
      payment_status = false
      #route to payment type
      case payment_method
        when "cash"
          payment_status = cash_payment
        when "creditnote"
          if !self.customer_id.nil?
            payment_status = creditnote_payment(self.customer_id)
          end
        when "visa"
           payment_status = external_terminal_card_payment(:visa)
        when "master"
           payment_status = external_terminal_card_payment(:master)
        when "jcb"
           payment_status = external_terminal_card_payment(:jcb)
        when "mpu"
           payment_status = external_terminal_card_payment(:mpu)
        when "unionpay"
           payment_status = external_terminal_card_payment(:unionpay)
        when "vochure"
           payment_status = vochure_payment
        when "giftcard"
           payment_status = giftcard_payment
        when "paypar"
          payment_status = paypar_payment
      else
         puts "it was something else"
      end

      #record an payment in sale-audit
      remark = "Payment #{payment_method}- for Invoice #{invoice.receipt_no} Due [#{amount_due}]| pay amount -> #{amount} | Payment Status ->#{payment_status}"
      sale_audit = SaleAudit.record_payment(invoice.id, remark, action_by)

      return true, self.sale
    else
      #record an payment in sale-audit
      remark = "No outstanding Amount - Grand Total [#{invoice.grand_total}] | Due [#{amount_due}] | Paid [#{invoice.amount_received}]"
      sale_audit = SaleAudit.record_payment(invoice.id, remark,action_by)

      return false, "No outstanding Amount"
    end

  end

  private
  def cash_payment
    payment_status = false
    self.payment_method = "cash"
    self.payment_amount = self.received_amount
    self.outstanding_amount = self.sale.grand_total - self.received_amount
    self.payment_status = "paid"
    payment_method = self.save!

    sale_update_payment_status(self.received_amount)

    return payment_status
  end

  def creditnote_payment(customer_id)

    payment_status = false

    self.payment_method = "creditnote"
    self.payment_amount = self.received_amount
    self.customer_id  = self.customer_id
    self.outstanding_amount = 0 - self.received_amount
    self.payment_status = "outstanding"
    payment_method = self.save!

    sale_update_payment_status(self.received_amount)

    return payment_status
  end

  def external_terminal_card_payment(method)
    payment_status = false

    self.payment_method = method
    self.payment_amount = self.received_amount
    self.payment_reference  = self.card_payment_reference
    self.outstanding_amount = self.sale.grand_total- self.received_amount
    self.payment_status = "paid"
    payment_method = self.save!

    sale_update_payment_status(self.received_amount)

    return payment_status
  end

  def voucher_payment
    payment_status = false

    #Next time - validate if the vochure number is valid - within
    self.payment_method = "voucher"
    self.payment_amount = self.received_amount
    self.payment_reference  = self.voucher_no
    self.outstanding_amount = self.sale.grand_total- self.received_amount
    self.payment_status = "paid"
    payment_method = self.save!

    sale_update_payment_status(self.received_amount)

    return payment_status

  end

  def giftcard_payment
    payment_status = false

    #Next time - validate if the vochure number is valid - within
    self.payment_method = "giftcard"
    self.payment_amount = self.received_amount
    self.payment_reference  = self.giftcard_no
    self.outstanding_amount = self.sale.grand_total- self.received_amount
    self.payment_status = "paid"
    payment_method = self.save!

    sale_update_payment_status(self.received_amount)

    return payment_status

  end

  def paypar_payment
    ##TODO - Integration with Paypar (SmartPay)
  end

  def sale_update_payment_status(paid_amount)
    puts "paid_amount"
    puts paid_amount
    #update amount_outstanding
    self.sale.amount_received =   self.sale.amount_received + paid_amount
    self.sale.amount_changed = amount - self.sale.amount_received
    if (self.sale.grand_total <=   self.sale.amount_received && self.sale.amount_changed > 0)
      self.sale.payment_status = "paid"
      self.sale.sale_status = "completed"
      self.sale.save!
    end

  end

  private
  def generate_custom_id
    self.sale_payment_id = SeedGenerator.generate_id(self.class.name, "SPI")
  end
end