package com.atlassian.core.util.thumbnail;
   
   import com.google.common.base.Optional;
   import org.junit.Before;
   import org.junit.Test;
   import org.mockito.Mock;
   import org.mockito.MockitoAnnotations;
   
   import javax.imageio.ImageReader;
  import javax.imageio.stream.ImageInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  
  import static org.hamcrest.CoreMatchers.equalTo;
  import static org.junit.Assert.assertThat;
  import static org.mockito.Mockito.verify;
  import static org.mockito.Mockito.when;
  
  public class DimensionsHelperTest {
  
      public static final int IMAGE_HEIGHT = 123456;
      public static final int IMAGE_WIDTH = 98765;
      @Mock
      private ImageReader imageReader;
      @Mock
      private InputStream inputStream;
  
      @Before
      public void setUp() throws Exception {
          MockitoAnnotations.initMocks(this);
      }
  
      @Test
      public void testGettingRightDimensionsInHappyPath() throws Exception {
          final DimensionsHelper dimensionsHelper = create(imageReader);
  
          when(imageReader.getHeight(0)).thenReturn(IMAGE_HEIGHT);
          when(imageReader.getWidth(0)).thenReturn(IMAGE_WIDTH);
  
          final Dimensions dimensions = dimensionsHelper.dimensionsForImage(inputStream);
  
          assertThat(dimensions.getHeight(), equalTo(IMAGE_HEIGHT));
          assertThat(dimensions.getWidth(), equalTo(IMAGE_WIDTH));
  
          verify(imageReader).dispose();
          verify(inputStream).close();
      }
  
      @Test(expected = IOException.class)
      public void testThrowsExceptionWhenCannotReadImage() throws Exception {
          final DimensionsHelper dimensionsHelper = create(null);
          
          dimensionsHelper.dimensionsForImage(inputStream);
      }
  
      /**
       * Testing extremely wide and tall images clamp minimum width and height to 1,
       * as per http://jira.atlassian.com/browse/JRA-20369
       */
      @Test
      public void testDetermineScaleSize() throws Exception {
          final DimensionsHelper dimensionsHelper = create(null);
          Dimensions dimensions = dimensionsHelper.determineScaledDimensions(20, 20, 1, 600);
          assertThat(dimensions.getWidth(), equalTo(1));
          assertThat(dimensions.getHeight(), equalTo(20));
  
          dimensions = dimensionsHelper.determineScaledDimensions(200, 200, 600, 1);
          assertThat(dimensions.getWidth(), equalTo(200));
          assertThat(dimensions.getHeight(), equalTo(1));
      }
  
      private DimensionsHelper create(final ImageReader imageReader) {
          return new DimensionsHelper() {
  
              @Override
              ImageInputStream getImageInputStream(InputStream inputStream) throws IOException {
                  return null;
              }
  
              @Override
              Optional<ImageReader> getImageReader(ImageInputStream inputStream) throws IOException {
                  return Optional.fromNullable(imageReader);
              }
  
          };
      }
  }