1 files changed, 47 insertions, 15 deletions

diff --git a/src/main/java/cuchaz/enigma/mapping/MappingsEnigmaWriter.java b/src/main/java/cuchaz/enigma/mapping/MappingsEnigmaWriter.java
index ba0720a..e1763d0 100644
--- a/src/main/java/cuchaz/enigma/mapping/MappingsEnigmaWriter.java
+++ b/src/main/java/cuchaz/enigma/mapping/MappingsEnigmaWriter.java
@@ -30,24 +30,14 @@ public class MappingsEnigmaWriter {
                         writeAsDirectory(out, mappings);
         }
 
-        private void deleteDir(File file) {
-                File[] contents = file.listFiles();
-                if (contents != null) {
-                        for (File f : contents) {
-                                deleteDir(f);
-                        }
-                }
-                file.delete();
-        }
-
         public void writeAsDirectory(File target, Mappings mappings) throws IOException {
-                //TODO: Know what have changes during write to not rewrite all the things
-                deleteDir(target);
                 if (!target.exists() && !target.mkdirs())
-                        throw  new IOException("Cannot create mapping directory!");
-
+                        throw new IOException("Cannot create mapping directory!");
 
                 for (ClassMapping classMapping : sorted(mappings.classes())) {
+                        if (!classMapping.isDirty())
+                                continue;
+                        this.deletePreviousClassMapping(target, classMapping);
                         File obFile = new File(target, classMapping.getObfFullName() + ".mapping");
                         File result;
                         if (classMapping.getDeobfName() == null)
@@ -68,8 +58,50 @@ public class MappingsEnigmaWriter {
                         outputWriter.close();
                 }
 
+                // Remove dropped mappings
+                List<ClassMapping> droppedClassMappings = new ArrayList<>(mappings.getPreviousState().classes());
+                List<ClassMapping> classMappings = new ArrayList<>(mappings.classes());
+                droppedClassMappings.removeAll(classMappings);
+                for (ClassMapping classMapping : droppedClassMappings)
+                {
+                        File obFile = new File(target, classMapping.getObfFullName() + ".mapping");
+                        File result;
+                        if (classMapping.getDeobfName() == null)
+                                result = obFile;
+                        else
+                        {
+                                // Make sure that old version of the file doesn't exist
+                                if (obFile.exists())
+                                        obFile.delete();
+                                result = new File(target, classMapping.getDeobfName() + ".mapping");
+                        }
+                        if (result.exists())
+                                result.delete();
+                }
         }
-        
+
+        private void deletePreviousClassMapping(File target, ClassMapping classMapping) {
+                File prevFile = null;
+                // Deob rename
+                if (classMapping.getDeobfName() != null && classMapping.getPreviousDeobfName() != null && !classMapping.getPreviousDeobfName().equals(classMapping.getDeobfName()))
+                {
+                        prevFile = new File(target, classMapping.getPreviousDeobfName() + ".mapping");
+                }
+                // Deob to ob rename
+                else if (classMapping.getDeobfName() == null && classMapping.getPreviousDeobfName() != null)
+                {
+                        prevFile = new File(target, classMapping.getPreviousDeobfName() + ".mapping");
+                }
+                // Ob to Deob rename
+                else if (classMapping.getDeobfName() != null && classMapping.getPreviousDeobfName() == null)
+                {
+                        prevFile = new File(target, classMapping.getObfFullName() + ".mapping");
+                }
+
+                if (prevFile != null && prevFile.exists())
+                        prevFile.delete();
+        }
+
         public void write(PrintWriter out, Mappings mappings) throws IOException {
                 for (ClassMapping classMapping : sorted(mappings.classes())) {
                         write(out, classMapping, 0);