Annotation editor support (#568)

* Add gutter markers

* Add more GUI APIs

* Use SVG icons for gutter markers

* Add a little more padding between the line numbers and the gutter markers

* Add API for creating an Enigma JEditorPane

* Add API to list all classes including library classes

* Add API to create a LocalVariableEntryView

* Expose BrdigeMethodIndex to API

* Require name to be passed to LocalVariableEntryView

* Make implementation of isCursorOnDeclaration more robust

* Checkstyle

* Replace isCursorOnDeclaration with getCursorDeclaration

* Checkstyle again

* Refactor EnigmaIcon as per Juuz's suggestions

* Add more @NonExtendable and add EnigmaIcon docs

24 files changed, 185 insertions, 2 deletions

diff --git a/enigma/src/main/java/cuchaz/enigma/EnigmaProject.java b/enigma/src/main/java/cuchaz/enigma/EnigmaProject.java
index 348e640..5242385 100644
--- a/enigma/src/main/java/cuchaz/enigma/EnigmaProject.java
+++ b/enigma/src/main/java/cuchaz/enigma/EnigmaProject.java
@@ -410,6 +410,11 @@ public class EnigmaProject implements ProjectView {
         }
 
         @Override
+        public Collection<String> getProjectAndLibraryClasses() {
+                return classProvider.getClassNames();
+        }
+
+        @Override
         @Nullable
         public ClassNode getBytecode(String className) {
                 return classProvider.get(className);
diff --git a/enigma/src/main/java/cuchaz/enigma/analysis/index/BridgeMethodIndex.java b/enigma/src/main/java/cuchaz/enigma/analysis/index/BridgeMethodIndex.java
index adb48ba..b852b5f 100644
--- a/enigma/src/main/java/cuchaz/enigma/analysis/index/BridgeMethodIndex.java
+++ b/enigma/src/main/java/cuchaz/enigma/analysis/index/BridgeMethodIndex.java
@@ -10,6 +10,8 @@ import java.util.concurrent.ConcurrentMap;
 
 import org.jetbrains.annotations.Nullable;
 
+import cuchaz.enigma.api.view.entry.MethodEntryView;
+import cuchaz.enigma.api.view.index.BridgeMethodIndexView;
 import cuchaz.enigma.translation.representation.AccessFlags;
 import cuchaz.enigma.translation.representation.MethodDescriptor;
 import cuchaz.enigma.translation.representation.TypeDescriptor;
@@ -17,7 +19,7 @@ import cuchaz.enigma.translation.representation.entry.ClassEntry;
 import cuchaz.enigma.translation.representation.entry.MethodDefEntry;
 import cuchaz.enigma.translation.representation.entry.MethodEntry;
 
-public class BridgeMethodIndex implements JarIndexer {
+public class BridgeMethodIndex implements JarIndexer, BridgeMethodIndexView {
         private final EntryIndex entryIndex;
         private final InheritanceIndex inheritanceIndex;
         private final ReferenceIndex referenceIndex;
@@ -154,6 +156,18 @@ public class BridgeMethodIndex implements JarIndexer {
                 return bridgeToSpecialized.get(bridge);
         }
 
+        @Override
+        @Nullable
+        public MethodEntryView getBridgeFromSpecialized(MethodEntryView specialized) {
+                return getBridgeFromSpecialized((MethodEntry) specialized);
+        }
+
+        @Override
+        @Nullable
+        public MethodEntryView getSpecializedFromBridge(MethodEntryView bridge) {
+                return getSpecializedFromBridge((MethodEntry) bridge);
+        }
+
         /** Includes "renamed specialized -> bridge" entries. */
         public Map<MethodEntry, MethodEntry> getSpecializedToBridge() {
                 return Collections.unmodifiableMap(specializedToBridge);
diff --git a/enigma/src/main/java/cuchaz/enigma/analysis/index/JarIndex.java b/enigma/src/main/java/cuchaz/enigma/analysis/index/JarIndex.java
index 5c5e2c3..242d750 100644
--- a/enigma/src/main/java/cuchaz/enigma/analysis/index/JarIndex.java
+++ b/enigma/src/main/java/cuchaz/enigma/analysis/index/JarIndex.java
@@ -204,6 +204,7 @@ public class JarIndex implements JarIndexer, JarIndexView {
                 return referenceIndex;
         }
 
+        @Override
         public BridgeMethodIndex getBridgeMethodIndex() {
                 return bridgeMethodIndex;
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/DataInvalidationEvent.java b/enigma/src/main/java/cuchaz/enigma/api/DataInvalidationEvent.java
index 812ad39..9396eff 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/DataInvalidationEvent.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/DataInvalidationEvent.java
@@ -2,8 +2,10 @@ package cuchaz.enigma.api;
 
 import java.util.Collection;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
+@ApiStatus.NonExtendable
 public interface DataInvalidationEvent {
         /**
          * The classes for which the invalidation applies, or {@code null} if the invalidation applies to all classes.
diff --git a/enigma/src/main/java/cuchaz/enigma/api/EnigmaIcon.java b/enigma/src/main/java/cuchaz/enigma/api/EnigmaIcon.java
new file mode 100644
index 0000000..4a4bd0e
--- /dev/null
+++ b/enigma/src/main/java/cuchaz/enigma/api/EnigmaIcon.java
@@ -0,0 +1,39 @@
+package cuchaz.enigma.api;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import org.jetbrains.annotations.ApiStatus;
+
+import cuchaz.enigma.utils.IconLoadingService;
+
+@ApiStatus.NonExtendable
+public interface EnigmaIcon {
+        /**
+         * Loads an icon resource from the given SVG resource path.
+         *
+         * @param resource the path to the resource to be loaded
+         * @return The loaded icon
+         * @throws IOException if the resource could not be found or an error occurred while reading it
+         */
+        static EnigmaIcon loadResource(String resource) throws IOException {
+                try (InputStream in = Thread.currentThread().getContextClassLoader().getResourceAsStream(resource)) {
+                        if (in == null) {
+                                throw new IOException("Could not find resource: " + resource);
+                        }
+
+                        return load(in);
+                }
+        }
+
+        /**
+         * Loads an icon in SVG format from the given input stream.
+         *
+         * @param in the input stream to load from
+         * @return The loaded icon
+         * @throws IOException if the stream throws an error
+         */
+        static EnigmaIcon load(InputStream in) throws IOException {
+                return IconLoadingService.INSTANCE.loadIcon(in);
+        }
+}
diff --git a/enigma/src/main/java/cuchaz/enigma/api/service/GuiService.java b/enigma/src/main/java/cuchaz/enigma/api/service/GuiService.java
index b00b94d..53b566f 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/service/GuiService.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/service/GuiService.java
@@ -5,7 +5,9 @@ import java.util.function.Supplier;
 
 import javax.swing.KeyStroke;
 
+import cuchaz.enigma.api.EnigmaIcon;
 import cuchaz.enigma.api.view.GuiView;
+import cuchaz.enigma.api.view.entry.EntryView;
 
 public interface GuiService extends EnigmaService {
         EnigmaServiceType<GuiService> TYPE = EnigmaServiceType.create("gui");
@@ -16,6 +18,9 @@ public interface GuiService extends EnigmaService {
         default void addToEditorContextMenu(GuiView gui, MenuRegistrar registrar) {
         }
 
+        default void addGutterMarkers(GuiView gui, EntryView entry, GutterMarkerAdder gutter) {
+        }
+
         interface MenuRegistrar {
                 void addSeparator();
 
@@ -31,4 +36,17 @@ public interface GuiService extends EnigmaService {
                 MenuItemBuilder setEnabledWhen(BooleanSupplier condition);
                 MenuItemBuilder setAction(Runnable action);
         }
+
+        interface GutterMarkerAdder {
+                GutterMarkerBuilder addMarker(EnigmaIcon icon, GutterMarkerAlignment alignment);
+        }
+
+        interface GutterMarkerBuilder {
+                GutterMarkerBuilder setClickAction(Runnable action);
+                GutterMarkerBuilder setTooltip(String tooltip);
+        }
+
+        enum GutterMarkerAlignment {
+                LEFT, RIGHT
+        }
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/GuiView.java b/enigma/src/main/java/cuchaz/enigma/api/view/GuiView.java
index 519a8ce..1d91573 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/GuiView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/GuiView.java
@@ -1,11 +1,15 @@
 package cuchaz.enigma.api.view;
 
+import javax.swing.JEditorPane;
 import javax.swing.JFrame;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
 import cuchaz.enigma.api.view.entry.EntryReferenceView;
+import cuchaz.enigma.api.view.entry.EntryView;
 
+@ApiStatus.NonExtendable
 public interface GuiView {
         @Nullable
         ProjectView getProject();
@@ -13,5 +17,14 @@ public interface GuiView {
         @Nullable
         EntryReferenceView getCursorReference();
 
+        @Nullable
+        EntryView getCursorDeclaration();
+
         JFrame getFrame();
+
+        float getScale();
+
+        boolean isDarkTheme();
+
+        JEditorPane createEditorPane();
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/ProjectView.java b/enigma/src/main/java/cuchaz/enigma/api/view/ProjectView.java
index b72e1c3..c8cb384 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/ProjectView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/ProjectView.java
@@ -3,6 +3,7 @@ package cuchaz.enigma.api.view;
 import java.util.Collection;
 import java.util.List;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 import org.objectweb.asm.tree.ClassNode;
 
@@ -11,6 +12,7 @@ import cuchaz.enigma.api.DataInvalidationListener;
 import cuchaz.enigma.api.view.entry.EntryView;
 import cuchaz.enigma.api.view.index.JarIndexView;
 
+@ApiStatus.NonExtendable
 public interface ProjectView {
         <T extends EntryView> T deobfuscate(T entry);
 
@@ -25,6 +27,8 @@ public interface ProjectView {
 
         Collection<String> getProjectClasses();
 
+        Collection<String> getProjectAndLibraryClasses();
+
         @Nullable
         ClassNode getBytecode(String className);
 
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassDefEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassDefEntryView.java
index 7cb1829..1fb6a7f 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassDefEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassDefEntryView.java
@@ -1,7 +1,9 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
+@ApiStatus.NonExtendable
 public interface ClassDefEntryView extends ClassEntryView, DefEntryView {
         @Nullable
         ClassEntryView getSuperClass();
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassEntryView.java
index 085188b..330920b 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/ClassEntryView.java
@@ -1,7 +1,10 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import cuchaz.enigma.translation.representation.entry.ClassEntry;
 
+@ApiStatus.NonExtendable
 public interface ClassEntryView extends EntryView {
         ClassEntryView getParent();
 
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/DefEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/DefEntryView.java
index bf246fb..a52e685 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/DefEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/DefEntryView.java
@@ -1,5 +1,8 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.NonExtendable
 public interface DefEntryView {
         int getAccessFlags();
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryReferenceView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryReferenceView.java
index d49aa1e..6ca87ab 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryReferenceView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryReferenceView.java
@@ -1,5 +1,8 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.NonExtendable
 public interface EntryReferenceView {
         EntryView getEntry();
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryView.java
index 2dad562..963c1e7 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/EntryView.java
@@ -1,7 +1,9 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
+@ApiStatus.NonExtendable
 public interface EntryView {
         /**
          * Returns the default name of this entry.
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/FieldEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/FieldEntryView.java
index ae44458..bf22814 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/FieldEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/FieldEntryView.java
@@ -1,9 +1,12 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import cuchaz.enigma.translation.representation.TypeDescriptor;
 import cuchaz.enigma.translation.representation.entry.ClassEntry;
 import cuchaz.enigma.translation.representation.entry.FieldEntry;
 
+@ApiStatus.NonExtendable
 public interface FieldEntryView extends EntryView {
         String getDescriptor();
 
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableDefEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableDefEntryView.java
index d091560..32e0af3 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableDefEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableDefEntryView.java
@@ -1,5 +1,8 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.NonExtendable
 public interface LocalVariableDefEntryView extends LocalVariableEntryView {
         String getDescriptor();
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableEntryView.java
index 391bc0f..b4728b5 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/LocalVariableEntryView.java
@@ -1,9 +1,19 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
+import cuchaz.enigma.translation.representation.entry.LocalVariableEntry;
+import cuchaz.enigma.translation.representation.entry.MethodEntry;
+
+@ApiStatus.NonExtendable
 public interface LocalVariableEntryView extends EntryView {
         int getIndex();
 
         boolean isArgument();
 
         MethodEntryView getParent();
+
+        static LocalVariableEntryView create(MethodEntryView parent, int index, String name, boolean argument) {
+                return new LocalVariableEntry((MethodEntry) parent, index, name, argument, null);
+        }
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/entry/MethodEntryView.java b/enigma/src/main/java/cuchaz/enigma/api/view/entry/MethodEntryView.java
index 7d7fcd2..3020afa 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/entry/MethodEntryView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/entry/MethodEntryView.java
@@ -1,9 +1,12 @@
 package cuchaz.enigma.api.view.entry;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import cuchaz.enigma.translation.representation.MethodDescriptor;
 import cuchaz.enigma.translation.representation.entry.ClassEntry;
 import cuchaz.enigma.translation.representation.entry.MethodEntry;
 
+@ApiStatus.NonExtendable
 public interface MethodEntryView extends EntryView {
         String getDescriptor();
 
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/index/BridgeMethodIndexView.java b/enigma/src/main/java/cuchaz/enigma/api/view/index/BridgeMethodIndexView.java
new file mode 100644
index 0000000..c07be88
--- /dev/null
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/index/BridgeMethodIndexView.java
@@ -0,0 +1,15 @@
+package cuchaz.enigma.api.view.index;
+
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.Nullable;
+
+import cuchaz.enigma.api.view.entry.MethodEntryView;
+
+@ApiStatus.NonExtendable
+public interface BridgeMethodIndexView {
+        @Nullable
+        MethodEntryView getBridgeFromSpecialized(MethodEntryView specialized);
+
+        @Nullable
+        MethodEntryView getSpecializedFromBridge(MethodEntryView bridge);
+}
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/index/EntryIndexView.java b/enigma/src/main/java/cuchaz/enigma/api/view/index/EntryIndexView.java
index 56bf70e..9b4fbaf 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/index/EntryIndexView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/index/EntryIndexView.java
@@ -2,10 +2,13 @@ package cuchaz.enigma.api.view.index;
 
 import java.util.Collection;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import cuchaz.enigma.api.view.entry.ClassDefEntryView;
 import cuchaz.enigma.api.view.entry.ClassEntryView;
 import cuchaz.enigma.api.view.entry.EntryView;
 
+@ApiStatus.NonExtendable
 public interface EntryIndexView {
         boolean hasEntry(EntryView entry);
         int getAccess(EntryView entry);
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/index/InheritanceIndexView.java b/enigma/src/main/java/cuchaz/enigma/api/view/index/InheritanceIndexView.java
index a016d11..a156155 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/index/InheritanceIndexView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/index/InheritanceIndexView.java
@@ -2,8 +2,11 @@ package cuchaz.enigma.api.view.index;
 
 import java.util.Collection;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import cuchaz.enigma.api.view.entry.ClassEntryView;
 
+@ApiStatus.NonExtendable
 public interface InheritanceIndexView {
         Collection<? extends ClassEntryView> getParents(ClassEntryView entry);
         Collection<? extends ClassEntryView> getChildren(ClassEntryView entry);
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/index/JarIndexView.java b/enigma/src/main/java/cuchaz/enigma/api/view/index/JarIndexView.java
index 069b115..b723267 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/index/JarIndexView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/index/JarIndexView.java
@@ -1,7 +1,11 @@
 package cuchaz.enigma.api.view.index;
 
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.NonExtendable
 public interface JarIndexView {
         EntryIndexView getEntryIndex();
         InheritanceIndexView getInheritanceIndex();
         ReferenceIndexView getReferenceIndex();
+        BridgeMethodIndexView getBridgeMethodIndex();
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/api/view/index/ReferenceIndexView.java b/enigma/src/main/java/cuchaz/enigma/api/view/index/ReferenceIndexView.java
index 00ab84e..7c0653f 100644
--- a/enigma/src/main/java/cuchaz/enigma/api/view/index/ReferenceIndexView.java
+++ b/enigma/src/main/java/cuchaz/enigma/api/view/index/ReferenceIndexView.java
@@ -2,11 +2,14 @@ package cuchaz.enigma.api.view.index;
 
 import java.util.Collection;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import cuchaz.enigma.api.view.entry.ClassEntryView;
 import cuchaz.enigma.api.view.entry.EntryReferenceView;
 import cuchaz.enigma.api.view.entry.FieldEntryView;
 import cuchaz.enigma.api.view.entry.MethodEntryView;
 
+@ApiStatus.NonExtendable
 public interface ReferenceIndexView {
         Collection<? extends MethodEntryView> getMethodsReferencedBy(MethodEntryView entry);
         Collection<? extends EntryReferenceView> getReferencesToClass(ClassEntryView entry);
diff --git a/enigma/src/main/java/cuchaz/enigma/source/SourceIndex.java b/enigma/src/main/java/cuchaz/enigma/source/SourceIndex.java
index fec20e2..51636e3 100644
--- a/enigma/src/main/java/cuchaz/enigma/source/SourceIndex.java
+++ b/enigma/src/main/java/cuchaz/enigma/source/SourceIndex.java
@@ -7,6 +7,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
 
+import org.jetbrains.annotations.Nullable;
+
 import cuchaz.enigma.analysis.EntryReference;
 import cuchaz.enigma.translation.mapping.EntryResolver;
 import cuchaz.enigma.translation.mapping.ResolutionStrategy;
@@ -17,11 +19,13 @@ public class SourceIndex {
         private List<Integer> lineOffsets;
         private final TreeMap<Token, EntryReference<Entry<?>, Entry<?>>> tokenToReference;
         private final Map<EntryReference<Entry<?>, Entry<?>>, Collection<Token>> referenceToTokens;
+        private final TreeMap<Token, Entry<?>> tokenToDeclaration;
         private final Map<Entry<?>, Token> declarationToToken;
 
         public SourceIndex() {
                 tokenToReference = new TreeMap<>();
                 referenceToTokens = new HashMap<>();
+                tokenToDeclaration = new TreeMap<>();
                 declarationToToken = new HashMap<>();
         }
 
@@ -80,6 +84,11 @@ public class SourceIndex {
                 return declarationToToken.get(entry);
         }
 
+        @Nullable
+        public Entry<?> getDeclaration(Token token) {
+                return tokenToDeclaration.get(token);
+        }
+
         public void addDeclaration(Token token, Entry<?> deobfEntry) {
                 if (token != null) {
                         EntryReference<Entry<?>, Entry<?>> reference = new EntryReference<>(deobfEntry, token.text);
@@ -88,6 +97,7 @@ public class SourceIndex {
                                         .add(token);
                         referenceToTokens.computeIfAbsent(EntryReference.declaration(deobfEntry, token.text), key -> new ArrayList<>())
                                         .add(token);
+                        tokenToDeclaration.put(token, deobfEntry);
                         declarationToToken.put(deobfEntry, token);
                 }
         }
@@ -108,6 +118,7 @@ public class SourceIndex {
                 return tokenToReference.keySet();
         }
 
+        @Nullable
         public Token getReferenceToken(int pos) {
                 Token token = tokenToReference.floorKey(new Token(pos, pos, null));
 
@@ -153,7 +164,9 @@ public class SourceIndex {
                 SourceIndex remapped = new SourceIndex(result.getSource());
 
                 for (Map.Entry<Entry<?>, Token> entry : declarationToToken.entrySet()) {
-                        remapped.declarationToToken.put(entry.getKey(), result.getRemappedToken(entry.getValue()));
+                        Token remappedToken = result.getRemappedToken(entry.getValue());
+                        remapped.declarationToToken.put(entry.getKey(), remappedToken);
+                        remapped.tokenToDeclaration.put(remappedToken, entry.getKey());
                 }
 
                 for (Map.Entry<EntryReference<Entry<?>, Entry<?>>, Collection<Token>> entry : referenceToTokens.entrySet()) {
diff --git a/enigma/src/main/java/cuchaz/enigma/utils/IconLoadingService.java b/enigma/src/main/java/cuchaz/enigma/utils/IconLoadingService.java
new file mode 100644
index 0000000..0e66fba
--- /dev/null
+++ b/enigma/src/main/java/cuchaz/enigma/utils/IconLoadingService.java
@@ -0,0 +1,14 @@
+package cuchaz.enigma.utils;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ServiceLoader;
+
+import cuchaz.enigma.api.EnigmaIcon;
+
+public interface IconLoadingService {
+        IconLoadingService INSTANCE = ServiceLoader.load(IconLoadingService.class).findFirst()
+                        .orElseThrow(() -> new IllegalStateException("Trying to load icon on headless Enigma"));
+
+        EnigmaIcon loadIcon(InputStream in) throws IOException;
+}