<tool id="scale_image" name="Scale Image" version="0.2">
  <description>Scales image</description>
  <requirements>
    <requirement type="package" version="0.14.0">scikit-image</requirement>
    <requirement type="package" version="1.1.0">scipy</requirement>
  </requirements>
  <command>
        <![CDATA[
        python '$__tool_directory__/scale_image.py' '$input' ./out.png
        #if $use_scale_option.use_scale == 'true'
          $use_scale_option.scale
        #else if $use_scale_option.use_scale == 'false'
          '[$use_scale_option.scale_x, $use_scale_option.scale_y]'
        #end if
        $order

        &&
        mv ./out.png '$output'
        ]]>
  </command>
  <inputs>
    <param name="input" type="data" format="png" label="Image file"/>
    <conditional name="use_scale_option"><!--a third option (using one integer as percentage scaling) could still be implemented-->
          <param label="Lock scaling between image dimensions" name="use_scale" type="select">
              <option selected="true" value="true">Lock</option>
              <option value="false">Individual scales</option>
          </param>
          <when value="true">
            <param name="scale" size="4" type="float" value="1.0" label="Scaling factor" />
          </when>
          <when value="false">
            <param name="scale_x" size="4" type="integer" value="100" label="New height of the image in pixels" />
            <param name="scale_y" size="4" type="integer" value="100" label="New width of the image in pixels" />
          </when>
    </conditional>
    <param name="order" type="select" label="Interpolation method">
      <option value="0">Nearest-neighbor</option>
      <option value="1" selected="true">Bi-linear</option>
      <option value="2">Bi-cubic</option>
    </param>
  </inputs>
  <outputs>
    <data format="png" name="output"/>
  </outputs>
    <tests>
      <test>
        <param name="input" value="sample1.png"/> <!--continue here-->
        <param name="use_scale_option.use_scale" value="false"/>
        <param name="use_scale_option.scale_x" value="200"/>
        <param name="use_scale_option.scale_y" value="150"/>
        <param name="order" value="0"/>
        <output name="output" value="out2.png" ftype="png" compare="sim_size"/>
      </test>
    </tests>  
  <help>This tool scales an image using the scaling factor.</help>
  <citations>
      <citation type="doi">10.1016/j.jbiotec.2017.07.019</citation>
  </citations>
</tool>