package com.atlassian.plugin.spring.scanner.core;
   
   import com.atlassian.plugin.spring.scanner.annotation.component.BambooComponent;
   import com.atlassian.plugin.spring.scanner.annotation.component.BitbucketComponent;
   import com.atlassian.plugin.spring.scanner.annotation.component.ClasspathComponent;
   import com.atlassian.plugin.spring.scanner.annotation.component.ConfluenceComponent;
   import com.atlassian.plugin.spring.scanner.annotation.component.FecruComponent;
   import com.atlassian.plugin.spring.scanner.annotation.component.JiraComponent;
   import com.atlassian.plugin.spring.scanner.annotation.component.RefappComponent;
  import com.atlassian.plugin.spring.scanner.annotation.component.StashComponent;
  import com.atlassian.plugin.spring.scanner.annotation.export.ExportAsDevService;
  import com.atlassian.plugin.spring.scanner.annotation.export.ExportAsService;
  import com.atlassian.plugin.spring.scanner.annotation.export.ModuleType;
  import com.atlassian.plugin.spring.scanner.annotation.imports.BambooImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.BitbucketImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.ComponentImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.ConfluenceImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.FecruImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.JiraImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.RefappImport;
  import com.atlassian.plugin.spring.scanner.annotation.imports.StashImport;
  import com.atlassian.plugin.spring.scanner.core.vfs.VirtualFile;
  import com.atlassian.plugin.spring.scanner.core.vfs.VirtualFileFactory;
  import com.atlassian.plugin.spring.scanner.util.CommonConstants;
  import com.google.common.base.Function;
  import com.google.common.collect.ImmutableList;
  import com.google.common.collect.Maps;
  import org.springframework.context.annotation.Primary;
  import org.springframework.stereotype.Component;
  import org.springframework.stereotype.Controller;
  import org.springframework.stereotype.Repository;
  import org.springframework.stereotype.Service;
  
  import javax.annotation.Nullable;
  import javax.inject.Named;
  import java.io.File;
  import java.io.IOException;
  import java.nio.file.FileVisitResult;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.nio.file.SimpleFileVisitor;
  import java.nio.file.attribute.BasicFileAttributes;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.TreeSet;
  
  import static com.atlassian.plugin.spring.scanner.ProductFilter.BAMBOO;
  import static com.atlassian.plugin.spring.scanner.ProductFilter.BITBUCKET;
  import static com.atlassian.plugin.spring.scanner.ProductFilter.CONFLUENCE;
  import static com.atlassian.plugin.spring.scanner.ProductFilter.FECRU;
  import static com.atlassian.plugin.spring.scanner.ProductFilter.JIRA;
  import static com.atlassian.plugin.spring.scanner.ProductFilter.REFAPP;
  import static com.atlassian.plugin.spring.scanner.ProductFilter.STASH;
  import static com.atlassian.plugin.spring.scanner.util.CommonConstants.COMPONENT_DEV_EXPORT_KEY;
  import static com.atlassian.plugin.spring.scanner.util.CommonConstants.COMPONENT_EXPORT_KEY;
  import static com.atlassian.plugin.spring.scanner.util.CommonConstants.COMPONENT_IMPORT_KEY;
  import static com.atlassian.plugin.spring.scanner.util.CommonConstants.COMPONENT_KEY;
  import static com.atlassian.plugin.spring.scanner.util.CommonConstants.COMPONENT_PRIMARY_KEY;
  import static java.util.Arrays.asList;
  
  
  /**
   * This class writes out the component and import index files into their specific directories and specific index files
   * names
   * <p>
   * The Reflections / Javassist code deals only in strings and hence this is written as such.
   */
  public class SpringIndexWriter {
      public static final List<String> KNOWN_PRODUCT_IMPORT_ANNOTATIONS = asList(
              BambooImport.class.getCanonicalName(),
              BitbucketImport.class.getCanonicalName(),
              ConfluenceImport.class.getCanonicalName(),
              FecruImport.class.getCanonicalName(),
              JiraImport.class.getCanonicalName(),
              RefappImport.class.getCanonicalName(),
              StashImport.class.getCanonicalName());
  
      private final Map<String, RecordedAnnotations> recordedProfiles = new HashMap<String, RecordedAnnotations>();
      private final VirtualFileFactory fileFactory;
  
      /**
       * A writer that can record and write index files of components
       *
       * @param baseDir the base directory to write to.  Typically this is the class file output directory
       */
      public SpringIndexWriter(final String baseDir) {
          // since we see EVERYTHING in the byte code scanner, we can always be clean
          // and start from scratch.
          cleanDirectory(new File(baseDir, CommonConstants.INDEX_FILES_DIR));
  
          fileFactory = new VirtualFileFactory(new File(baseDir));
      }
  
      public boolean isInteresting(String annotationType) {
          return (null != MeaningfulAnnotation.fromCanonicalName(annotationType));
      }
 
     public boolean isParameterOrFieldAnnotation(final String annotationType) {
         final MeaningfulAnnotation meaningfulAnnotation = MeaningfulAnnotation.fromCanonicalName(annotationType);
         return (null != meaningfulAnnotation) && meaningfulAnnotation.parameterOrFieldAnnotation;
     }
 
     public void encounteredAnnotation(Set<String> targetProfiles, String annotationType, String nameFromAnnotation, String className) {
         Set<String> profiles = new HashSet<String>(targetProfiles);
         if (profiles.isEmpty()) {
             // when we have no profiles, we go into the magic one called 'default'
             profiles.add(CommonConstants.DEFAULT_PROFILE_NAME);
         }
 
         for (String profile : profiles) {
             RecordedAnnotations recordedAnnotations = recordedProfiles.get(profile);
             if (recordedAnnotations == null) {
                 recordedAnnotations = new RecordedAnnotations();
                 recordedProfiles.put(profile, recordedAnnotations);
             }
             recordedAnnotations.record(annotationType, nameFromAnnotation, className);
         }
 
     }
 
     public void writeIndexes() {
         for (Map.Entry<String, RecordedAnnotations> annotationsEntry : recordedProfiles.entrySet()) {
             writeProfileIndexes(annotationsEntry.getKey(), annotationsEntry.getValue());
         }
 
     }
 
     private void writeProfileIndexes(final String profileName, final RecordedAnnotations annotations) {
         //
         // the javac annotation processing only allows you to open a file for input and output ONCE
         // for reasons you can look up online.  Basically so its knows what it has seen before.
         // So if you open a file, write to it and then try to repeat that it will blow up.
         //
         // So we need to collapse the map here so that we go from many annotations sharing the
         // same index file to a map of index file ---> all components for that index file
         //
         // and then write it out per unique file so they are only opened once.
         //
         Map<String, Set<String>> fileNameToComponents = new HashMap<String, Set<String>>();
         for (Map.Entry<MeaningfulAnnotation, Set<String>> entry : annotations.getRecordedAnnotations().entrySet()) {
             MeaningfulAnnotation meaningfulAnnotation = entry.getKey();
             if (meaningfulAnnotation.isWrittenToDisk()) {
                 Set<String> perAnnotationComponents = entry.getValue();
                 String indexFileName = meaningfulAnnotation.getFileName();
                 Set<String> currentComponents = fileNameToComponents.get(indexFileName);
                 if (currentComponents == null) {
                     currentComponents = new TreeSet<String>();
                     fileNameToComponents.put(indexFileName, currentComponents);
                 }
                 currentComponents.addAll(perAnnotationComponents);
             }
         }
         //
         // now that we have them in file name order we can write them safely under the javac world
         for (Map.Entry<String, Set<String>> entry : fileNameToComponents.entrySet()) {
             try {
                 writeIndexFile(profileName, entry.getKey(), entry.getValue());
             } catch (IOException e) {
                 throw new RuntimeException(e);
             }
         }
     }
 
     private void writeIndexFile(final String profileName, final String indexFileName, final Set<String> entries)
             throws IOException {
         File file = makeProfiledFileName(profileName, indexFileName);
 
         VirtualFile vf = fileFactory.getFile(file.getPath());
 
         Set<String> lines = new TreeSet<String>();
         // read the existing lines
         lines.addAll(vf.readLines());
         lines.addAll(entries);
         vf.writeLines(lines);
     }
 
     private File makeProfiledFileName(final String profileName, String fileName) throws IOException {
         File file = new File(CommonConstants.PROFILE_PREFIX + profileName, fileName);
         if (CommonConstants.DEFAULT_PROFILE_NAME.equals(profileName)) {
             // the well known default profile goes into the top level directory
             // and only explicitly defined profiles go into sub directories
             file = new File(fileName);
         }
         return new File(CommonConstants.INDEX_FILES_DIR, file.getPath());
     }
 
     private void cleanDirectory(final File destination) {
         if (destination.exists()) {
             try {
                 Files.walkFileTree(destination.toPath(), new SimpleFileVisitor<Path>() {
                     @Override
                     public FileVisitResult postVisitDirectory(Path dir, IOException e) throws IOException {
                         if (e != null) {
                             throw e;
                         }
                         Files.delete(dir);
                         return FileVisitResult.CONTINUE;
                     }
 
                     @Override
                     public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
                         Files.delete(file);
                         return FileVisitResult.CONTINUE;
                     }
                 });
             } catch (IOException e) {
                 throw new RuntimeException("Unable to delete directory " + destination, e);
             }
         }
     }
 
     private enum MeaningfulAnnotation {
         // Well known spring annotations
         Component(COMPONENT_KEY, Component.class),
         Service(COMPONENT_KEY, Service.class),
         Controller(COMPONENT_KEY, Controller.class),
         Repository(COMPONENT_KEY, Repository.class),
         Primary(COMPONENT_PRIMARY_KEY, Primary.class),
 
         // JSR annotations
         Named(COMPONENT_KEY, Named.class, true),
 
         // Our component annotations
         ClasspathComponent(COMPONENT_KEY, ClasspathComponent.class, true),
         BambooComponent(BAMBOO.getPerProductFile(COMPONENT_KEY), BambooComponent.class, true),
         BitbucketComponent(BITBUCKET.getPerProductFile(COMPONENT_KEY), BitbucketComponent.class, true),
         ConfluenceComponent(CONFLUENCE.getPerProductFile(COMPONENT_KEY), ConfluenceComponent.class, true),
         JiraComponent(JIRA.getPerProductFile(COMPONENT_KEY), JiraComponent.class, true),
         FecruComponent(FECRU.getPerProductFile(COMPONENT_KEY), FecruComponent.class, true),
         RefappComponent(REFAPP.getPerProductFile(COMPONENT_KEY), RefappComponent.class, true),
         StashComponent(STASH.getPerProductFile(COMPONENT_KEY), StashComponent.class, true),
 
         // Our import annotations
         Imports(COMPONENT_IMPORT_KEY, ComponentImport.class, true),
         BambooImports(BAMBOO.getPerProductFile(COMPONENT_IMPORT_KEY), BambooImport.class, true),
         BitbucketImports(BITBUCKET.getPerProductFile(COMPONENT_IMPORT_KEY), BitbucketImport.class, true),
         ConfluenceImports(CONFLUENCE.getPerProductFile(COMPONENT_IMPORT_KEY), ConfluenceImport.class, true),
         FecruImports(FECRU.getPerProductFile(COMPONENT_IMPORT_KEY), FecruImport.class, true),
         JiraImports(JIRA.getPerProductFile(COMPONENT_IMPORT_KEY), JiraImport.class, true),
         RefappImports(REFAPP.getPerProductFile(COMPONENT_IMPORT_KEY), RefappImport.class, true),
         StashImports(STASH.getPerProductFile(COMPONENT_IMPORT_KEY), StashImport.class, true),
 
         // Our export annotations
         ExportAsService(COMPONENT_EXPORT_KEY, ExportAsService.class, true),
         ExportAsDevService(COMPONENT_DEV_EXPORT_KEY, ExportAsDevService.class, true),
         ModuleType(COMPONENT_EXPORT_KEY, ModuleType.class);
 
         private static final Map<String, MeaningfulAnnotation> canonicalNameIndex = Maps.uniqueIndex(
                 ImmutableList.copyOf(values()),
                 new Function<MeaningfulAnnotation, String>() {
                     @Override
                     public String apply(@Nullable final MeaningfulAnnotation meaningfulAnnotation) {
                         return meaningfulAnnotation.forAnnotation.getCanonicalName();
                     }
                 });
 
         private final String fileName;
         private final Class forAnnotation;
         private final boolean parameterOrFieldAnnotation;
 
         MeaningfulAnnotation(final String fileName, final Class forAnnotation) {
             this(fileName, forAnnotation, false);
         }
 
         MeaningfulAnnotation(final Class forAnnotation) {
             this(null, forAnnotation, false);
         }
 
         MeaningfulAnnotation(final String fileName, final Class forAnnotation, boolean parameterOrFieldAnnotation) {
             this.fileName = fileName;
             this.forAnnotation = forAnnotation;
             this.parameterOrFieldAnnotation = parameterOrFieldAnnotation;
         }
 
         private static MeaningfulAnnotation fromCanonicalName(String annotationType) {
             return canonicalNameIndex.get(annotationType);
         }
 
         private String getFileName() {
             return fileName;
         }
 
         private boolean isWrittenToDisk() {
             return null != fileName;
         }
     }
 
     /**
      * Simple holder class to record sets of annotations as we traverse the classes
      */
     private class RecordedAnnotations {
         final Map<MeaningfulAnnotation, Set<String>> recordedAnnotations = new HashMap<MeaningfulAnnotation, Set<String>>();
 
         public Map<MeaningfulAnnotation, Set<String>> getRecordedAnnotations() {
             return recordedAnnotations;
         }
 
         public void record(final String annotationType, final String nameFromAnnotation, final String className) {
             StringBuilder sb = new StringBuilder(className);
             if (nameFromAnnotation != null) {
                 String trimmed = nameFromAnnotation.trim();
                 if (!trimmed.isEmpty()) {
                     sb.append("#").append(trimmed);
                 }
             }
             final MeaningfulAnnotation annotation = MeaningfulAnnotation.fromCanonicalName(annotationType);
             if (null == annotation) {
                 throw new IllegalStateException("Stop asking me for the impossible. Annotation " + annotationType + " not found");
             }
 
             addTo(annotation, sb.toString());
         }
 
         private void addTo(final MeaningfulAnnotation meaningfulAnnotation, final String value) {
             Set<String> values = recordedAnnotations.get(meaningfulAnnotation);
             if (values == null) {
                 values = new TreeSet<String>();
                 recordedAnnotations.put(meaningfulAnnotation, values);
             }
             values.add(value);
         }
     }
 
 
 }