# coding: utf-8
module Paperclip
  class Watermark < Processor
    attr_accessor :current_geometry, :target_geometry, :format, :whiny, :convert_options, :watermark_path, :overlay, :position

    def initialize file, options = {}, attachment = nil
      super
      geometry          = options[:geometry]
      @file             = file
      @crop             = geometry[-1,1] == '#'
      @target_geometry  = Geometry.parse geometry
      @current_geometry = Geometry.from_file @file
      @convert_options  = options[:convert_options]
      @whiny            = options[:whiny].nil? ? true : options[:whiny]
      @format           = options[:format]
      @watermark_path   = options[:watermark_path]
      @position         = options[:position].nil? ? "SouthEast" : options[:position]
      @overlay          = options[:overlay].nil? ? true : false
      @current_format   = File.extname(@file.path)
      @basename         = File.basename(@file.path, @current_format)
    end

    # Returns true if the +target_geometry+ is meant to crop.
    def crop?
      @crop
    end

    # Returns true if the image is meant to make use of additional convert options.
    def convert_options?
      not @convert_options.blank?
    end

    # Performs the conversion of the +file+ into a watermark. Returns the Tempfile
    # that contains the new image.
    def make
      dst = Tempfile.new([@basename, @format].compact.join("."))
      dst.binmode
      if watermark_path
        command = "composite"
        params = "-gravity #{@position} #{watermark_path} #{fromfile} #{transformation_command} #{tofile(dst)}"
      else
        command = "convert"
        params = "#{fromfile} #{transformation_command} #{tofile(dst)}"
      end
      begin
        success = Paperclip.run(command, params)
      rescue PaperclipCommandLineError
        raise PaperclipError, "There was an error processing the watermark for #{@basename}" if @whiny
      end
      dst
    end

    def fromfile
      "\"#{ File.expand_path(@file.path) }[0]\""
    end

    def tofile(destination)
      "\"#{ File.expand_path(destination.path) }[0]\""
    end

    def transformation_command
      scale, crop = @current_geometry.transformation_to(@target_geometry, crop?)
      trans = "-resize \"#{scale}\""
      trans << " -crop \"#{crop}\" +repage" if crop
      trans << " #{convert_options}" if convert_options?
      trans
    end
  end
end