simple codes

app/prints/base_esc.rb

@@ -11,7 +11,6 @@ def write(data)
     escpos_data = data.respond_to?(:to_escpos) ? data.to_escpos : data
     @data << escpos_data.force_encoding("ASCII-8BIT")
   end
-  alias :<< :write
 
   def partial_cut!
     @data << EscHelper.sequence(Escpos::PAPER_PARTIAL_CUT)
@@ -29,4 +28,171 @@ def to_escpos
     @data
   end
 
+  # Encodes UTF-8 string to encoding acceptable for the printer
+  # The printer must be set to that encoding
+  # Available encodings can be listed in console using Encoding.constants
+  def encode(data, opts = {})
+    data.encode(opts.fetch(:encoding), 'UTF-8', {
+      invalid: opts.fetch(:invalid, :replace),
+      undef: opts.fetch(:undef, :replace),
+      replace: opts.fetch(:replace, '?')
+    })
+  end
+
+  # Set printer encoding
+  # example: encoding(Escpos::CP_ISO8859_2)
+  def encoding(data)
+    [
+      sequence(Escpos::CP_SET),
+      sequence(data)
+    ].join
+  end
+
+  def text(data)
+    [
+      sequence(Escpos::TXT_NORMAL),
+      data,
+      sequence(Escpos::TXT_NORMAL),
+    ].join
+  end
+
+  def double_height(data)
+    [
+      sequence(Escpos::TXT_2HEIGHT),
+      data,
+      sequence(Escpos::TXT_NORMAL),
+    ].join
+  end
+
+  def quad_text(data)
+    [
+      sequence(Escpos::TXT_4SQUARE),
+      data,
+      sequence(Escpos::TXT_NORMAL),
+    ].join
+  end
+
+  def double_width(data)
+    [
+      sequence(Escpos::TXT_2WIDTH),
+      data,
+      sequence(Escpos::TXT_NORMAL),
+    ].join
+  end
+
+  def underline(data)
+    [
+      sequence(Escpos::TXT_UNDERL_ON),
+      data,
+      sequence(Escpos::TXT_UNDERL_OFF),
+    ].join
+  end
+
+  def underline2(data)
+    [
+      sequence(Escpos::TXT_UNDERL2_ON),
+      data,
+      sequence(Escpos::TXT_UNDERL_OFF),
+    ].join
+  end
+
+  def bold(data)
+    [
+      sequence(Escpos::TXT_BOLD_ON),
+      data,
+      sequence(Escpos::TXT_BOLD_OFF),
+    ].join
+  end
+
+  def left(data = '')
+    [
+      sequence(Escpos::TXT_ALIGN_LT),
+      data,
+      sequence(Escpos::TXT_ALIGN_LT),
+    ].join
+  end
+
+  def right(data = '')
+    [
+      sequence(Escpos::TXT_ALIGN_RT),
+      data,
+      sequence(Escpos::TXT_ALIGN_LT),
+    ].join
+  end
+
+  def center(data = '')
+    [
+      sequence(Escpos::TXT_ALIGN_CT),
+      data,
+      sequence(Escpos::TXT_ALIGN_LT),
+    ].join
+  end
+
+  def inverted(data)
+    [
+      sequence(Escpos::TXT_INVERT_ON),
+      data,
+      sequence(Escpos::TXT_INVERT_OFF),
+    ].join
+  end
+
+  def black
+    [
+      sequence(Escpos::TXT_COLOR_BLACK),
+      data,
+      sequence(Escpos::TXT_COLOR_BLACK),
+    ].join
+  end
+
+  def red
+    [
+      sequence(Escpos::TXT_COLOR_BLACK),
+      data,
+      sequence(Escpos::TXT_COLOR_RED),
+    ].join
+  end
+
+  def barcode(data, opts = {})
+    text_position = opts.fetch(:text_position, Escpos::BARCODE_TXT_OFF)
+    possible_text_positions = [
+      Escpos::BARCODE_TXT_OFF,
+      Escpos::BARCODE_TXT_ABV,
+      Escpos::BARCODE_TXT_BLW,
+      Escpos::BARCODE_TXT_BTH
+    ]
+    unless possible_text_positions.include?(text_position)
+      raise ArgumentError("Wrong text position.")
+    end
+    height = opts.fetch(:height, 50)
+    if height && (height < 1 || height > 255)
+      raise ArgumentError("Height must be in range from 1 to 255.")
+    end
+    width = opts.fetch(:width, 3)
+    if width && (width < 2 || width > 6)
+      raise ArgumentError("Width must be in range from 2 to 6.")
+    end
+    [
+      sequence(text_position),
+      sequence(Escpos::BARCODE_WIDTH),
+      sequence([width]),
+      sequence(Escpos::BARCODE_HEIGHT),
+      sequence([height]),
+      sequence(opts.fetch(:format, Escpos::BARCODE_EAN13)),
+      data
+    ].join
+  end
+
+  def partial_cut
+    sequence(Escpos::PAPER_PARTIAL_CUT)
+  end
+
+  def cut
+    sequence(Escpos::PAPER_FULL_CUT)
+  end
+
+  # Transforms an array of codes into a string
+  def sequence(*arr_sequence)
+    arr_sequence.flatten.pack('U*')
+  end
+
 end