class Invoice
  def initialize(args = {})
    @invoice = args[:invoice] # assign invoice object from args.
    @cer = args[:cer] # path to .cer file.
    @pem = args[:pem] # path to .pem file.
    @pass = args[:password] # password of .pem file.
    invoice_cfdi
    @invoice_cfdi.transmitter = transmitter # assign transmitter to invoice.
    @invoice_cfdi.receptor = receptor # assign receptor to invoice.
    add_concepts # add concepts to invoice.
    add_taxes # add taxes to invoice.
    certificate_invoice # create certificate and stamp for invoice.
  end

  def invoice_cfdi
    @invoice_cfdi = MCFDI::Invoice.new(
      folio: @invoice.folio, series: @invoice.series,
      created_at: @invoice.created_at,
      proof_type: I18n.t("invoice_proof_types.#{@invoice.proof_type}"),
      payment_way: @invoice.payment_way,
      payment_conditions: @invoice.payment_conditions,
      payment_method: @invoice.payment_method,
      expedition_place: @invoice.expedition_place,
      total: @invoice.total, subtotal: @invoice.subtotal
    )
  end

  def transmitter
    { rfc: @invoice.seller.rfc, business_name: @invoice.seller.business_name,
      address: address(@invoice.seller),
      fiscal_regime: @invoice.seller.fiscal_regime }
  end

  def receptor
    { rfc: @invoice.buyer.rfc, business_name: @invoice.buyer.business_name,
      address: address(@invoice.buyer) }
  end

  def address(entity)
    { street: entity.street, street_number: entity.street_number,
      interior_number: entity.interior_number,
      neighborhood: entity.neighborhood, location: entity.location,
      reference: entity.reference, city: entity.city, state: entity.state,
      country: entity.country, zip_code: entity.zip_code }
  end

  def add_concepts
    @invoice.invoice_items.each do |ii|
      @invoice_cfdi.concepts << MCFDI::Concept.new(
        quantity: ii.quantity, measure_unit: ii.measure_unit,
        code: ii.code, name: ii.name, price: ii.price, import: ii.import
      )
    end
  end

  def add_taxes
    iva if @invoice.iva > 0
    ieps if @invoice.ieps > 0
    detained_iva if @invoice.detained_iva > 0
    isr if @invoice.isr > 0
  end

  def iva
    @invoice_cfdi.taxes.transferred << MCFDI::Transferred.new(
      tax: 'IVA', rate: 16, import: @invoice.iva)
  end

  def ieps
    @invoice_cfdi.taxes.transferred << MCFDI::Transferred.new(
      tax: 'IEPS', rate: 12, import: @invoice.ieps)
  end

  def detained_iva
    @invoice_cfdi.taxes.detained << MCFDI::Detained.new(
      tax: 'IVA', rate: 16, import: @invoice.detained_iva)
  end

  def isr
    @invoice_cfdi.taxes.detained << MCFDI::Detained.new(
      tax: 'ISR', rate: 16, import: @invoice.isr)
  end

  # create certificate and stamp for invoice.
  def certificate_invoice
    certificate = MCFDI::Certificate.new(@cer)
    key = MCFDI::Key.new(@pem, @pass)
    certificate.certificate(@invoice_cfdi)
    key.seal(@invoice_cfdi)
  end

  # return original string create by CFDI gem.
  def original_string
    @invoice_cfdi.original_string
  end

  # validate original string with schema.
  def validate_original_string
    @invoice_cfdi.validate_original_string
  end

  # return original string created by the schema.
  def original_string_from_xslt
    @invoice_cfdi.original_string
  end

  # return xml of the invoice and save it to file (before seal it with SAT).
  def xml
    file = File.new("#{@invoice.full_folio}-not-billed.xml", "wb")
    file.write(@invoice_cfdi.to_xml)
    file.close
    @invoice_cfdi.to_xml
  end

  # validate xml with schema and return errors.
  def validate_xml
    @invoice_cfdi.validate_xml
  end
end

@invoice = '{YOUR INVOICE OBJECT}'
@in = Invoice.new(
  invoice: @invoice, cer: 'CERTIFICATION_FILE_PATH',
  pem: 'PEM_FILE_PATH",
  password: 'PASSWORD'
)
@in.xml
@in.original_string
@in.total_to_words # will return total in words.
@in.qr_code # will return 'data:image/png;base64,...'

MCFDI.from_xml(XML_STRING)

MCFDI.proof_types
MCFDI.payment_methods
MCFDI.payment_ways