module Magick::RVG::Transformable

def add_transform_primitives(gc)
  @transforms.each { |transform| gc.__send__(transform[0], *transform[1]) }
end

def initialize(*args, &block)
  super()
  @transforms = Transforms.new
end

def matrix(sx, rx, ry, sy, tx, ty)
  begin
    @transforms << [:affine, [Float(sx), Float(rx), Float(ry), Float(sy), Float(tx), Float(ty)]]
  rescue ArgumentError
    raise ArgumentError, "arguments must be convertable to float (got #{sx.class}, #{rx.class}, #{ry.class}, #{sy.class}, #{sx.class}, #{sx.class}, #{tx.class}, #{ty.class})"
  end
  yield(self) if block_given?
  self
end

def rotate(angle, *args)
  begin
    case args.length
      when 0
        @transforms << [:rotate, [Float(angle)]]
      when 2
        cx = Float(args[0])
        cy = Float(args[1])
        @transforms << [:translate, [cx, cy]]
        @transforms << [:rotate, [angle]]
        @transforms << [:translate, [-cx, -cy]]
      else
        fail ArgumentError, "wrong number of arguments (#{args.length} for 1 or 3)"
    end
  rescue ArgumentError
    raise ArgumentError, "arguments must be convertable to float (got #{[angle, *args].collect {|a| a.class}.join(', ')})"
  end
  yield(self) if block_given?
  self
end

def scale(sx, sy = nil)
  sy ||= sx
  begin
    @transforms << [:scale, [Float(sx), Float(sy)]]
  rescue ArgumentError
    raise ArgumentError, "arguments must be convertable to float (got #{sx.class}, #{sy.class})"
  end
  yield(self) if block_given?
  self
end

def skewX(angle)
  begin
    @transforms << [:skewx, [Float(angle)]]
  rescue ArgumentError
    raise ArgumentError, "argument must be convertable to float (got #{angle.class})"
  end
  yield(self) if block_given?
  self
end

def skewY(angle)
  begin
    @transforms << [:skewy, [Float(angle)]]
  rescue ArgumentError
    raise ArgumentError, "argument must be convertable to float (got #{angle.class})"
  end
  yield(self) if block_given?
  self
end

def translate(tx, ty = nil)
  ty ||= tx
  begin
    @transforms << [:translate, [Float(tx), Float(ty)]]
  rescue ArgumentError
    raise ArgumentError, "arguments must be convertable to float (got #{tx.class}, #{ty.class})"
  end
  yield(self) if block_given?
  self
end