package com.atlassian.plugin.loaders;
   
   import com.atlassian.plugin.loaders.classloading.DeploymentUnit;
   import com.atlassian.plugin.test.PluginTestUtils;
   import com.google.common.base.Function;
   import org.apache.commons.io.FileUtils;
   import org.hamcrest.Matcher;
   import org.junit.After;
   import org.junit.Before;
  import org.junit.Test;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.List;
  
  import static com.atlassian.plugin.loaders.classloading.TestDeploymentUnit.deploymentUnitWithPath;
  import static com.google.common.collect.Lists.transform;
  import static org.apache.commons.io.FileUtils.deleteQuietly;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.Matchers.containsInAnyOrder;
  import static org.hamcrest.Matchers.empty;
  import static org.hamcrest.Matchers.equalTo;
  import static org.hamcrest.Matchers.is;
  
  public class TestRosterFileScanner {
      private File temporaryDirectory;
      private File rosterFile;
  
      private RosterFileScanner rosterFileScanner;
  
      @Before
      public void setUp() throws Exception {
          temporaryDirectory = PluginTestUtils.createTempDirectory(RosterFileScanner.class);
          rosterFile = new File(temporaryDirectory, "rosterFile.list");
          rosterFileScanner = new RosterFileScanner(rosterFile);
      }
  
      @After
      public void tearDown() throws Exception {
          deleteQuietly(temporaryDirectory);
      }
  
      @Test
      public void scanOfMissingFileIsEmpty() {
          assertThat(rosterFileScanner.scan(), empty());
      }
  
      @Test
      public void scanAndGetDeploymentUnitsWithAbsolutePaths() throws Exception {
          final List<File> expectedFiles = writeRosterFile(rosterFile, "/absoluteSimple", "/absolute/compound");
  
          // First scan should yield expected deployment units
          assertThat(rosterFileScanner.scan(), containsDeploymentUnitsFor(expectedFiles));
          // A get should also yield expected deployment units
          assertThat(rosterFileScanner.getDeploymentUnits(), containsDeploymentUnitsFor(expectedFiles));
      }
  
      @Test
      public void scanAndGetDeploymentUnitsWithRelativePaths() throws Exception {
          final List<File> expectedFiles = writeRosterFile(rosterFile, "relativeSimple", "relative/simple");
  
          // First scan should yield expected deployment units
          assertThat(rosterFileScanner.scan(), containsDeploymentUnitsFor(expectedFiles));
          // A get should also yield expected deployment units
          assertThat(rosterFileScanner.getDeploymentUnits(), containsDeploymentUnitsFor(expectedFiles));
      }
  
      @Test
      public void getDeploymentUnitsIsEmptyBeforeScan() {
          assertThat(rosterFileScanner.getDeploymentUnits(), empty());
      }
  
      @Test
      public void scanAfterResetReturnsDeploymentUnits() throws Exception {
          final List<File> expectedFiles = writeRosterFile(rosterFile, "/one", "/two");
  
          // First scan should yield expected deployment units
          assertThat(rosterFileScanner.scan(), containsDeploymentUnitsFor(expectedFiles));
          // A get should also yield expected deployment units
          assertThat(rosterFileScanner.getDeploymentUnits(), containsDeploymentUnitsFor(expectedFiles));
          // Subsequent scan should yield no new deployment units
          assertThat(rosterFileScanner.scan(), empty());
  
          rosterFileScanner.reset();
  
          // After reset, a get should see nothing
          assertThat(rosterFileScanner.getDeploymentUnits(), empty());
          // A new scan should yield the expected deployment units
          assertThat(rosterFileScanner.scan(), containsDeploymentUnitsFor(expectedFiles));
          // At which point get should see them also
          assertThat(rosterFileScanner.getDeploymentUnits(), containsDeploymentUnitsFor(expectedFiles));
      }
  
      @Test
      public void scanAfterFileUpdateYieldsNewUnits() throws Exception {
          final List<File> expectedBefore = writeRosterFile(rosterFile, "/one", "/two", "/three");
          // We need the file modified time to change when we update it, so just backdate the first copy
         backdateFile(rosterFile);
 
         assertThat(rosterFileScanner.scan(), containsDeploymentUnitsFor(expectedBefore));
         assertThat(rosterFileScanner.getDeploymentUnits(), containsDeploymentUnitsFor(expectedBefore));
 
         final List<File> expectedGetAfter = writeRosterFile(rosterFile, "/three", "/four", "/five");
         // This is a tiny bit brittle, but doing better is quite a pain - we know only 1 element is common with before
         final List<File> expectedScanAfter = expectedGetAfter.subList(1, expectedGetAfter.size());
 
         assertThat(rosterFileScanner.scan(), containsDeploymentUnitsFor(expectedScanAfter));
         assertThat(rosterFileScanner.getDeploymentUnits(), containsDeploymentUnitsFor(expectedGetAfter));
     }
 
     @Test
     public void removeDoesNotFail() {
         final DeploymentUnit deploymentUnit = new DeploymentUnit(new File("removed"));
         rosterFileScanner.remove(deploymentUnit);
     }
 
     @Test
     public void isKnownRosterFileFormatTrueForList() {
         assertThat(RosterFileScanner.isKnownRosterFileFormat(new File("some.list")), is(true));
     }
 
     @Test
     public void isKnownRosterFileFormatFalseForUnsuffixed() {
         assertThat(RosterFileScanner.isKnownRosterFileFormat(new File("unsuffixed")), is(false));
     }
 
     public static List<File> writeRosterFile(final File rosterFile, final String... paths)
             throws IOException {
         final List<String> listOfPaths = Arrays.asList(paths);
         FileUtils.writeLines(rosterFile, listOfPaths);
         return transform(listOfPaths, new Function<String, File>() {
             @Override
             public File apply(final String path) {
                 // Infer whether the path is absolute or not. A quick check is good enough for tests where we control the input
                 // data, and has the added advantage of keeping us independent of the implementation of this feature.
                 final boolean absolute = File.separatorChar == path.charAt(0);
                 return absolute ? new File(path) : new File(rosterFile.getParentFile(), path);
             }
         });
     }
 
     public static void backdateFile(final File file) throws Exception {
         if (!file.setLastModified(file.lastModified() - 2000)) {
             throw new Exception("Unable to backdate file '" + file + "'");
         }
     }
 
     private static Matcher<Iterable<? extends DeploymentUnit>> containsDeploymentUnitsFor(final List<File> files) {
         final List<Matcher<DeploymentUnit>> matchers = transform(files, new Function<File, Matcher<DeploymentUnit>>() {
             @Override
             public Matcher<DeploymentUnit> apply(final File file) {
                 return deploymentUnitWithPath(equalTo(file));
             }
         });
 
         // I don't seem able to get the right overload of containsInAnyOrder without the unchecked cast
         //noinspection unchecked
         return containsInAnyOrder((Collection) matchers);
     }
 }