module ChunkyPNG

def self.Color(*args)
  case args.length
    when 1; ChunkyPNG::Color.parse(args.first)
    when 2; (ChunkyPNG::Color.parse(args.first) & 0xffffff00) | args[1].to_i
    when 3; ChunkyPNG::Color.rgb(*args)
    when 4; ChunkyPNG::Color.rgba(*args)
    else raise ArgumentError, "Don't know how to create a color from #{args.inspect}!"
  end
end

def self.Dimension(*args)
  case args.length
    when 2; ChunkyPNG::Dimension.new(*args)
    when 1; case source = args.first
        when ChunkyPNG::Dimension; source
        when ChunkyPNG::Point; ChunkyPNG::Dimension.new(source.x, source.y)
        when Array; ChunkyPNG::Dimension.new(source[0], source[1])
        when Hash;  ChunkyPNG::Dimension.new(source[:width] || source['width'], source[:height] || source['height'])
        when ChunkyPNG::Dimension::DIMENSION_REGEXP; ChunkyPNG::Dimension.new($1, $2)
        else
          if source.respond_to?(:width) && source.respond_to?(:height)
            ChunkyPNG::Dimension.new(source.width, source.height)
          else
            raise ArgumentError, "Don't know how to construct a point from #{source.inspect}!"
          end
      end
    else raise ArgumentError, "Don't know how to construct a point from #{args.inspect}!"
  end
end

def self.Point(*args)
  case args.length
    when 2; ChunkyPNG::Point.new(*args)
    when 1; case source = args.first
        when ChunkyPNG::Point; source
        when ChunkyPNG::Dimension; ChunkyPNG::Point.new(source.width, source.height)
        when Array; ChunkyPNG::Point.new(source[0], source[1])
        when Hash; ChunkyPNG::Point.new(source[:x] || source['x'], source[:y] || source['y'])
        when ChunkyPNG::Point::POINT_REGEXP; ChunkyPNG::Point.new($1.to_i, $2.to_i)
        else 
          if source.respond_to?(:x) && source.respond_to?(:y)
            ChunkyPNG::Point.new(source.x, source.y)
          else
            raise ArgumentError, "Don't know how to construct a point from #{source.inspect}!"
          end
      end
    else raise ArgumentError, "Don't know how to construct a point from #{args.inspect}!"
  end
end

def self.Vector(*args)
  
  return args.first if args.length == 1 && args.first.kind_of?(ChunkyPNG::Vector)
  
  if args.length == 1 && args.first.respond_to?(:scan)
    ChunkyPNG::Vector.new(ChunkyPNG::Vector.multiple_from_string(args.first)) # e.g. ['1,1 2,2 3,3']
  else
    ChunkyPNG::Vector.new(ChunkyPNG::Vector.multiple_from_array(args)) # e.g. [[1,1], [2,2], [3,3]] or [1,1,2,2,3,3]
  end
end

def self.force_binary(str)
  str.respond_to?(:force_encoding) ? str.force_encoding('BINARY') : str
end