Merge pull request #7 from marhali/dev

Fix Issues // Add Features

### Added
- Filter option for translation files via regex / issue #5
- Support for splitted / modularized json files per locale / issue #4
- Basic translation key completion inside editor
- I18n key annotation inside editor

### Changed
- Tree view will be expanded if search function has been used

### Fixed
- Encoding for properties files / issue #6

CHANGELOG.md

@@ -4,6 +4,19 @@
 
 ## [Unreleased]
 
+## [1.1.0] - 2021-04-25
+### Added
+- Filter option for translation files via regex / issue #5
+- Support for splitted / modularized json files per locale / issue #4
+- Basic translation key completion inside editor
+- I18n key annotation inside editor
+
+### Changed
+- Tree view will be expanded if search function has been used
+
+### Fixed
+- Encoding for properties files / issue #6
+
 ## [1.0.1] - 2021-03-16
 ### Changed
 - Modified plugin icon to meet IntelliJ guidelines

gradle.properties

@@ -3,7 +3,7 @@
 
 pluginGroup = de.marhali.easyi18n
 pluginName = easy-i18n
-pluginVersion = 1.0.1
+pluginVersion = 1.1.0
 pluginSinceBuild = 202
 pluginUntilBuild = 203.*
 # Plugin Verifier integration -> https://github.com/JetBrains/gradle-intellij-plugin#plugin-verifier-dsl

src/main/java/de/marhali/easyi18n/io/TranslatorIO.java

@@ -1,5 +1,7 @@
 package de.marhali.easyi18n.io;
 
+import com.intellij.openapi.project.Project;
+
 import de.marhali.easyi18n.model.Translations;
 
 import org.jetbrains.annotations.NotNull;
@@ -15,16 +17,19 @@ public interface TranslatorIO {
 
     /**
      * Reads localized messages from the persistence layer.
+     * @param project Opened intellij project
      * @param directoryPath The full path for the directory which holds all locale files
      * @param callback Contains loaded translations. Will be called after io operation. Content might be null on failure.
      */
-    void read(@NotNull String directoryPath, @NotNull Consumer<Translations> callback);
+    void read(@NotNull Project project, @NotNull String directoryPath, @NotNull Consumer<Translations> callback);
 
     /**
      * Writes the provided messages (translations) to the persistence layer.
+     * @param project Opened intellij project
      * @param translations Translations instance to save
      * @param directoryPath The full path for the directory which holds all locale files
      * @param callback Will be called after io operation. Can be used to determine if action was successful(true) or not
      */
-    void save(@NotNull Translations translations, @NotNull String directoryPath, @NotNull Consumer<Boolean> callback);
+    void save(@NotNull Project project, @NotNull Translations translations,
+              @NotNull String directoryPath, @NotNull Consumer<Boolean> callback);
 }

src/main/java/de/marhali/easyi18n/io/implementation/JsonTranslatorIO.java

@@ -2,12 +2,15 @@ package de.marhali.easyi18n.io.implementation;
 
 import com.google.gson.*;
 import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.LocalFileSystem;
 import com.intellij.openapi.vfs.VirtualFile;
 
 import de.marhali.easyi18n.io.TranslatorIO;
 import de.marhali.easyi18n.model.LocalizedNode;
 import de.marhali.easyi18n.model.Translations;
+import de.marhali.easyi18n.util.IOUtil;
+import de.marhali.easyi18n.util.JsonUtil;
 
 import org.jetbrains.annotations.NotNull;
 
@@ -26,7 +29,7 @@ public class JsonTranslatorIO implements TranslatorIO {
     private static final String FILE_EXTENSION = "json";
 
     @Override
-    public void read(@NotNull String directoryPath, @NotNull Consumer<Translations> callback) {
+    public void read(@NotNull Project project, @NotNull String directoryPath, @NotNull Consumer<Translations> callback) {
         ApplicationManager.getApplication().saveAll(); // Save opened files (required if new locales were added)
 
         ApplicationManager.getApplication().runReadAction(() -> {
@@ -43,9 +46,17 @@ public class JsonTranslatorIO implements TranslatorIO {
 
             try {
                 for(VirtualFile file : files) {
+
+                    if(!IOUtil.isFileRelevant(project, file)) { // File does not matches pattern
+                        continue;
+                    }
+
                     locales.add(file.getNameWithoutExtension());
-                    JsonObject tree = JsonParser.parseReader(new InputStreamReader(file.getInputStream(), file.getCharset())).getAsJsonObject();
+
-                    readTree(file.getNameWithoutExtension(), tree, nodes);
+                    JsonObject tree = JsonParser.parseReader(new InputStreamReader(file.getInputStream(),
+                            file.getCharset())).getAsJsonObject();
+
+                    JsonUtil.readTree(file.getNameWithoutExtension(), tree, nodes);
                 }
 
                 callback.accept(new Translations(locales, nodes));
@@ -58,20 +69,25 @@ public class JsonTranslatorIO implements TranslatorIO {
     }
 
     @Override
-    public void save(@NotNull Translations translations, @NotNull String directoryPath, @NotNull Consumer<Boolean> callback) {
+    public void save(@NotNull Project project, @NotNull Translations translations,
+                     @NotNull String directoryPath, @NotNull Consumer<Boolean> callback) {
+
         Gson gson = new GsonBuilder().setPrettyPrinting().create();
 
         ApplicationManager.getApplication().runWriteAction(() -> {
             try {
                 for(String locale : translations.getLocales()) {
                     JsonObject content = new JsonObject();
-                    writeTree(locale, content, translations.getNodes());
+                    JsonUtil.writeTree(locale, content, translations.getNodes());
-                    //JsonElement content = writeTree(locale, new JsonObject(), translations.getNodes());
 
                     String fullPath = directoryPath + "/" + locale + "." + FILE_EXTENSION;
-                    VirtualFile file = LocalFileSystem.getInstance().findFileByIoFile(new File(fullPath));
+                    File file = new File(fullPath);
+                    boolean created = file.createNewFile();
 
-                    file.setBinaryContent(gson.toJson(content).getBytes(file.getCharset()));
+                    VirtualFile vf = created ? LocalFileSystem.getInstance().refreshAndFindFileByIoFile(file)
+                            : LocalFileSystem.getInstance().findFileByIoFile(file);
+
+                    vf.setBinaryContent(gson.toJson(content).getBytes(vf.getCharset()));
                 }
 
                 // Successfully saved
@@ -83,57 +99,4 @@ public class JsonTranslatorIO implements TranslatorIO {
             }
         });
     }
-
-    private void writeTree(String locale, JsonObject parent, LocalizedNode node) {
-        if(node.isLeaf() && !node.getKey().equals(LocalizedNode.ROOT_KEY)) {
-            if(node.getValue().get(locale) != null) {
-                parent.add(node.getKey(), new JsonPrimitive(node.getValue().get(locale)));
-            }
-
-        } else {
-            for(LocalizedNode children : node.getChildren()) {
-                if(children.isLeaf()) {
-                    writeTree(locale, parent, children);
-                } else {
-                    JsonObject childrenJson = new JsonObject();
-                    writeTree(locale, childrenJson, children);
-                    if(childrenJson.size() > 0) {
-                        parent.add(children.getKey(), childrenJson);
-                    }
-                }
-            }
-        }
-    }
-
-    private void readTree(String locale, JsonObject json, LocalizedNode data) {
-        for(Map.Entry<String, JsonElement> entry : json.entrySet()) {
-            String key = entry.getKey();
-
-            try {
-                // Try to go one level deeper
-                JsonObject childObject = entry.getValue().getAsJsonObject();
-
-                LocalizedNode childrenNode = data.getChildren(key);
-
-                if(childrenNode == null) {
-                    childrenNode = new LocalizedNode(key, new ArrayList<>());
-                    data.addChildren(childrenNode);
-                }
-
-                readTree(locale, childObject, childrenNode);
-
-            } catch(IllegalStateException e) { // Reached end for this node
-                LocalizedNode leafNode = data.getChildren(key);
-
-                if(leafNode == null) {
-                    leafNode = new LocalizedNode(key, new HashMap<>());
-                    data.addChildren(leafNode);
-                }
-
-                Map<String, String> messages = leafNode.getValue();
-                messages.put(locale, entry.getValue().getAsString());
-                leafNode.setValue(messages);
-            }
-        }
-    }
 }

src/main/java/de/marhali/easyi18n/io/implementation/ModularizedJsonTranslatorIO.java

@@ -0,0 +1,121 @@
+package de.marhali.easyi18n.io.implementation;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vfs.LocalFileSystem;
+import com.intellij.openapi.vfs.VirtualFile;
+
+import de.marhali.easyi18n.io.TranslatorIO;
+import de.marhali.easyi18n.model.LocalizedNode;
+import de.marhali.easyi18n.model.Translations;
+import de.marhali.easyi18n.util.IOUtil;
+import de.marhali.easyi18n.util.JsonUtil;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Consumer;
+
+/**
+ * IO operations for splitted / modularized json files. Each locale can have multiple translation files.
+ * @author marhali
+ */
+public class ModularizedJsonTranslatorIO implements TranslatorIO {
+
+    private static final String FILE_EXTENSION = "json";
+
+    @Override
+    public void read(@NotNull Project project, @NotNull String directoryPath, @NotNull Consumer<Translations> callback) {
+        ApplicationManager.getApplication().saveAll(); // Save opened files (required if new locales were added)
+
+        ApplicationManager.getApplication().runReadAction(() -> {
+            VirtualFile directory = LocalFileSystem.getInstance().findFileByIoFile(new File(directoryPath));
+
+            if(directory == null || directory.getChildren() == null) {
+                throw new IllegalArgumentException("Specified folder is invalid (" + directoryPath + ")");
+            }
+
+            VirtualFile[] localeDirectories = directory.getChildren();
+
+            List<String> locales = new ArrayList<>();
+            LocalizedNode nodes = new LocalizedNode(LocalizedNode.ROOT_KEY, new ArrayList<>());
+
+            try {
+                for(VirtualFile localeDir : localeDirectories) {
+                    String locale = localeDir.getName();
+                    locales.add(locale);
+
+                    // Read all json modules
+                    for(VirtualFile module : localeDir.getChildren()) {
+
+                        if(!IOUtil.isFileRelevant(project, module)) { // File does not matches pattern
+                            continue;
+                        }
+
+                        JsonObject tree = JsonParser.parseReader(new InputStreamReader(module.getInputStream(),
+                                module.getCharset())).getAsJsonObject();
+
+                        String moduleName = module.getNameWithoutExtension();
+                        LocalizedNode moduleNode = nodes.getChildren(moduleName);
+
+                        if(moduleNode == null) { // Create module / sub node
+                            moduleNode = new LocalizedNode(moduleName, new ArrayList<>());
+                            nodes.addChildren(moduleNode);
+                        }
+
+                        JsonUtil.readTree(locale, tree, moduleNode);
+                    }
+                }
+
+                callback.accept(new Translations(locales, nodes));
+
+            } catch(IOException e) {
+                e.printStackTrace();
+                callback.accept(null);
+            }
+        });
+    }
+
+    @Override
+    public void save(@NotNull Project project, @NotNull Translations translations,
+                     @NotNull String directoryPath, @NotNull Consumer<Boolean> callback) {
+
+        Gson gson = new GsonBuilder().setPrettyPrinting().create();
+
+        ApplicationManager.getApplication().runWriteAction(() -> {
+            try {
+                for(String locale : translations.getLocales()) {
+                    // Use top level children as modules
+                    for (LocalizedNode module : translations.getNodes().getChildren()) {
+                        JsonObject content = new JsonObject();
+                        JsonUtil.writeTree(locale, content, module);
+
+                        String fullPath = directoryPath + "/" + locale + "/" + module.getKey() + "." + FILE_EXTENSION;
+                        File file = new File(fullPath);
+                        boolean created = file.createNewFile();
+
+                        VirtualFile vf = created ? LocalFileSystem.getInstance().refreshAndFindFileByIoFile(file)
+                                : LocalFileSystem.getInstance().findFileByIoFile(file);
+
+                        vf.setBinaryContent(gson.toJson(content).getBytes(vf.getCharset()));
+                    }
+                }
+
+                // Successfully saved
+                callback.accept(true);
+
+            } catch(IOException e) {
+                e.printStackTrace();
+                callback.accept(false);
+            }
+        });
+    }
+}

src/main/java/de/marhali/easyi18n/io/implementation/PropertiesTranslatorIO.java

@@ -1,20 +1,19 @@
 package de.marhali.easyi18n.io.implementation;
 
 import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.LocalFileSystem;
 import com.intellij.openapi.vfs.VirtualFile;
 
 import de.marhali.easyi18n.io.TranslatorIO;
 import de.marhali.easyi18n.model.LocalizedNode;
 import de.marhali.easyi18n.model.Translations;
+import de.marhali.easyi18n.util.IOUtil;
 import de.marhali.easyi18n.util.TranslationsUtil;
 
 import org.jetbrains.annotations.NotNull;
 
-import java.io.ByteArrayOutputStream;
+import java.io.*;
-import java.io.File;
-import java.io.IOException;
-import java.io.InputStreamReader;
 import java.util.*;
 import java.util.function.Consumer;
 
@@ -27,7 +26,7 @@ public class PropertiesTranslatorIO implements TranslatorIO {
     public static final String FILE_EXTENSION = "properties";
 
     @Override
-    public void read(@NotNull String directoryPath, @NotNull Consumer<Translations> callback) {
+    public void read(@NotNull Project project, @NotNull String directoryPath, @NotNull Consumer<Translations> callback) {
         ApplicationManager.getApplication().saveAll(); // Save opened files (required if new locales were added)
 
         ApplicationManager.getApplication().runReadAction(() -> {
@@ -44,9 +43,14 @@ public class PropertiesTranslatorIO implements TranslatorIO {
 
             try {
                 for (VirtualFile file : files) {
+
+                    if(!IOUtil.isFileRelevant(project, file)) { // File does not matches pattern
+                        continue;
+                    }
+
                     locales.add(file.getNameWithoutExtension());
                     Properties properties = new Properties();
-                    properties.load(new InputStreamReader(file.getInputStream(), file.getCharset()));;
+                    properties.load(new InputStreamReader(file.getInputStream(), file.getCharset()));
                     readProperties(file.getNameWithoutExtension(), properties, nodes);
                 }
 
@@ -60,7 +64,9 @@ public class PropertiesTranslatorIO implements TranslatorIO {
     }
 
     @Override
-    public void save(@NotNull Translations translations, @NotNull String directoryPath, @NotNull Consumer<Boolean> callback) {
+    public void save(@NotNull Project project, @NotNull Translations translations,
+                     @NotNull String directoryPath, @NotNull Consumer<Boolean> callback) {
+
         ApplicationManager.getApplication().runWriteAction(() -> {
             try {
                 for(String locale : translations.getLocales()) {
@@ -70,8 +76,9 @@ public class PropertiesTranslatorIO implements TranslatorIO {
                     String fullPath = directoryPath + "/" + locale + "." + FILE_EXTENSION;
                     VirtualFile file = LocalFileSystem.getInstance().findFileByIoFile(new File(fullPath));
 
-                    ByteArrayOutputStream content = new ByteArrayOutputStream();
+                    StringWriter content = new StringWriter();
                     properties.store(content, "I18n " + locale + " keys");
+
                     file.setBinaryContent(content.toString().getBytes(file.getCharset()));
                 }
 

src/main/java/de/marhali/easyi18n/model/SettingsState.java

@@ -10,8 +10,10 @@ import org.jetbrains.annotations.Nullable;
 public class SettingsState {
 
     public static final String DEFAULT_PREVIEW_LOCALE = "en";
+    public static final String DEFAULT_FILE_PATTERN = ".*";
 
     private String localesPath;
+    private String filePattern;
     private String previewLocale;
 
     public SettingsState() {}
@@ -24,6 +26,14 @@ public class SettingsState {
         this.localesPath = localesPath;
     }
 
+    public @NotNull String getFilePattern() {
+        return filePattern != null ? filePattern : DEFAULT_FILE_PATTERN;
+    }
+
+    public void setFilePattern(String filePattern) {
+        this.filePattern = filePattern;
+    }
+
     public @NotNull String getPreviewLocale() {
         return previewLocale != null ? previewLocale : DEFAULT_PREVIEW_LOCALE;
     }

src/main/java/de/marhali/easyi18n/service/DataStore.java

@@ -63,7 +63,7 @@ public class DataStore {
         } else {
             TranslatorIO io = IOUtil.determineFormat(localesPath);
 
-            io.read(localesPath, (translations) -> {
+            io.read(project, localesPath, (translations) -> {
                 if(translations != null) { // Read was successful
                     this.translations = translations;
 
@@ -80,7 +80,7 @@ public class DataStore {
     }
 
     /**
-     * Saves the current translation state to disk. See {@link TranslatorIO#save(Translations, String, Consumer)}
+     * Saves the current translation state to disk. See {@link TranslatorIO#save(Project, Translations, String, Consumer)}
      * @param callback Complete callback. Indicates if operation was successful(true) or not
      */
     public void saveToDisk(@NotNull Consumer<Boolean> callback) {
@@ -91,7 +91,7 @@ public class DataStore {
         }
 
         TranslatorIO io = IOUtil.determineFormat(localesPath);
-        io.save(translations, localesPath, callback);
+        io.save(project, translations, localesPath, callback);
     }
 
     /**

src/main/java/de/marhali/easyi18n/ui/dialog/SettingsDialog.java

@@ -24,6 +24,7 @@ public class SettingsDialog {
     private final Project project;
 
     private TextFieldWithBrowseButton pathText;
+    private JBTextField filePatternText;
     private JBTextField previewText;
 
     public SettingsDialog(Project project) {
@@ -32,10 +33,12 @@ public class SettingsDialog {
 
     public void showAndHandle() {
         String localesPath = SettingsService.getInstance(project).getState().getLocalesPath();
+        String filePattern = SettingsService.getInstance(project).getState().getFilePattern();
         String previewLocale = SettingsService.getInstance(project).getState().getPreviewLocale();
 
-        if(prepare(localesPath, previewLocale).show() == DialogWrapper.OK_EXIT_CODE) { // Save changes
+        if(prepare(localesPath, filePattern, previewLocale).show() == DialogWrapper.OK_EXIT_CODE) { // Save changes
             SettingsService.getInstance(project).getState().setLocalesPath(pathText.getText());
+            SettingsService.getInstance(project).getState().setFilePattern(filePatternText.getText());
             SettingsService.getInstance(project).getState().setPreviewLocale(previewText.getText());
 
             // Reload instance
@@ -43,7 +46,7 @@ public class SettingsDialog {
         }
     }
 
-    private DialogBuilder prepare(String localesPath, String previewLocale) {
+    private DialogBuilder prepare(String localesPath, String filePattern, String previewLocale) {
         JPanel rootPanel = new JPanel(new GridLayout(0, 1, 2, 2));
 
         JBLabel pathLabel = new JBLabel(ResourceBundle.getBundle("messages").getString("settings.path.text"));
@@ -56,6 +59,13 @@ public class SettingsDialog {
         rootPanel.add(pathLabel);
         rootPanel.add(pathText);
 
+        JBLabel filePatternLabel = new JBLabel(ResourceBundle.getBundle("messages").getString("settings.path.file-pattern"));
+        filePatternText = new JBTextField(filePattern);
+
+        rootPanel.add(filePatternLabel);
+        rootPanel.add(filePatternText);
+
+
         JBLabel previewLabel = new JBLabel(ResourceBundle.getBundle("messages").getString("settings.preview"));
         previewText = new JBTextField(previewLocale);
         previewLabel.setLabelFor(previewText);

src/main/java/de/marhali/easyi18n/ui/editor/I18nCompletionContributor.java

@@ -0,0 +1,18 @@
+package de.marhali.easyi18n.ui.editor;
+
+import com.intellij.codeInsight.completion.CompletionContributor;
+import com.intellij.codeInsight.completion.CompletionType;
+import com.intellij.patterns.*;
+import com.intellij.psi.PsiLiteralValue;
+
+/**
+ * Show i18n key completion for literal values.
+ * @author marhali
+ */
+public class I18nCompletionContributor extends CompletionContributor {
+
+    public I18nCompletionContributor() {
+        extend(CompletionType.BASIC, PlatformPatterns.psiElement().inside(PsiLiteralValue.class),
+                new I18nCompletionProvider());
+    }
+}

src/main/java/de/marhali/easyi18n/ui/editor/I18nCompletionProvider.java

@@ -0,0 +1,66 @@
+package de.marhali.easyi18n.ui.editor;
+
+import com.intellij.codeInsight.completion.CompletionParameters;
+import com.intellij.codeInsight.completion.CompletionProvider;
+import com.intellij.codeInsight.completion.CompletionResultSet;
+import com.intellij.codeInsight.lookup.LookupElementBuilder;
+import com.intellij.ide.DataManager;
+import com.intellij.openapi.actionSystem.PlatformDataKeys;
+import com.intellij.openapi.project.Project;
+import com.intellij.util.ProcessingContext;
+
+import de.marhali.easyi18n.model.LocalizedNode;
+import de.marhali.easyi18n.service.DataStore;
+import de.marhali.easyi18n.service.SettingsService;
+import de.marhali.easyi18n.util.TranslationsUtil;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+/**
+ * I18n translation key completion provider.
+ * @author marhali
+ */
+public class I18nCompletionProvider extends CompletionProvider<CompletionParameters> {
+
+    private Project project;
+    private String previewLocale;
+
+    public I18nCompletionProvider() {
+        DataManager.getInstance().getDataContextFromFocusAsync().onSuccess(data -> {
+           project = PlatformDataKeys.PROJECT.getData(data);
+           previewLocale = SettingsService.getInstance(project).getState().getPreviewLocale();
+        });
+    }
+
+    @Override
+    protected void addCompletions(@NotNull CompletionParameters parameters, @NotNull ProcessingContext context, @NotNull CompletionResultSet result) {
+        String query = result.getPrefixMatcher().getPrefix();
+        List<String> sections = TranslationsUtil.getSections(query);
+        String lastSection = null;
+
+        if(!sections.isEmpty() && !query.endsWith(".")) {
+            lastSection = sections.remove(sections.size() - 1);
+        }
+
+        String path = TranslationsUtil.sectionsToFullPath(sections);
+
+        LocalizedNode node = sections.isEmpty() ? DataStore.getInstance(project).getTranslations().getNodes()
+                : DataStore.getInstance(project).getTranslations().getNode(path);
+
+        for(LocalizedNode children : node.getChildren()) {
+            if(lastSection == null || children.getKey().startsWith(lastSection)) {
+                // Construct full key path / Fore nested objects add '.' to indicate deeper level
+                String fullKey = (path.isEmpty() ? children.getKey() : path + "." + children.getKey()) + (children.isLeaf() ? "" : ".");
+
+                result.addElement(LookupElementBuilder.create(fullKey).appendTailText(getTailText(children), true));
+            }
+        }
+    }
+
+    private String getTailText(LocalizedNode node) {
+        return !node.isLeaf() ? " I18n([])"
+                : " I18n(" + previewLocale + ": " + node.getValue().get(previewLocale) + ")";
+    }
+}

src/main/java/de/marhali/easyi18n/ui/editor/I18nKeyAnnotator.java

@@ -0,0 +1,56 @@
+package de.marhali.easyi18n.ui.editor;
+
+import com.intellij.ide.DataManager;
+import com.intellij.lang.annotation.AnnotationHolder;
+import com.intellij.lang.annotation.Annotator;
+import com.intellij.lang.annotation.HighlightSeverity;
+import com.intellij.openapi.actionSystem.PlatformDataKeys;
+import com.intellij.openapi.project.Project;
+import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiLiteralValue;
+import de.marhali.easyi18n.model.LocalizedNode;
+import de.marhali.easyi18n.service.DataStore;
+import de.marhali.easyi18n.service.SettingsService;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Translation key annotator.
+ * @author marhali
+ */
+public class I18nKeyAnnotator implements Annotator {
+
+    private Project project;
+    private String previewLocale;
+
+    public I18nKeyAnnotator() {
+        DataManager.getInstance().getDataContextFromFocusAsync().onSuccess(data -> {
+            project = PlatformDataKeys.PROJECT.getData(data);
+            previewLocale = SettingsService.getInstance(project).getState().getPreviewLocale();
+        });
+    }
+
+    @Override
+    public void annotate(@NotNull PsiElement element, @NotNull AnnotationHolder holder) {
+        if(!(element instanceof PsiLiteralValue)) {
+            return;
+        }
+
+        PsiLiteralValue literalValue = (PsiLiteralValue) element;
+        String value = literalValue.getValue() instanceof String ? (String) literalValue.getValue() : null;
+
+        if(value == null) {
+            return;
+        }
+
+        LocalizedNode node = DataStore.getInstance(project).getTranslations().getNode(value);
+
+        if(node == null) { // Unknown translation. Just ignore it
+            return;
+        }
+
+        String tooltip = node.isLeaf() ? "I18n(" + previewLocale + ": " + node.getValue().get(previewLocale) + ")"
+                : "I18n ([])";
+
+        holder.newAnnotation(HighlightSeverity.INFORMATION, tooltip).create();
+    }
+}

src/main/java/de/marhali/easyi18n/ui/tabs/TreeView.java

@@ -77,6 +77,10 @@ public class TreeView implements DataSynchronizer {
     @Override
     public void synchronize(@NotNull Translations translations, @Nullable String searchQuery) {
         tree.setModel(new TreeModelTranslator(project, translations, searchQuery));
+
+        if(searchQuery != null && !searchQuery.isEmpty()) {
+            expandAll().run();
+        }
     }
 
     private void handlePopup(MouseEvent e) {

src/main/java/de/marhali/easyi18n/util/IOUtil.java

@@ -1,11 +1,14 @@
 package de.marhali.easyi18n.util;
 
+import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.LocalFileSystem;
 import com.intellij.openapi.vfs.VirtualFile;
 import de.marhali.easyi18n.io.implementation.JsonTranslatorIO;
+import de.marhali.easyi18n.io.implementation.ModularizedJsonTranslatorIO;
 import de.marhali.easyi18n.io.implementation.PropertiesTranslatorIO;
 import de.marhali.easyi18n.io.TranslatorIO;
 
+import de.marhali.easyi18n.service.SettingsService;
 import org.jetbrains.annotations.NotNull;
 
 import java.io.File;
@@ -36,6 +39,11 @@ public class IOUtil {
             throw new IllegalStateException("Could not determine i18n format. At least one locale file must be defined");
         }
 
+        // Split files - Should be always JSON
+        if(any.get().isDirectory()) {
+            return new ModularizedJsonTranslatorIO();
+        }
+
         switch (any.get().getFileType().getDefaultExtension().toLowerCase()) {
             case "json":
                 return new JsonTranslatorIO();
@@ -48,4 +56,15 @@ public class IOUtil {
                         any.get().getFileType().getDefaultExtension());
         }
     }
+
+    /**
+     * Checks if the provided file matches the file pattern specified by configuration
+     * @param project Current intellij project
+     * @param file File to check
+     * @return True if relevant otherwise false
+     */
+    public static boolean isFileRelevant(Project project, VirtualFile file) {
+        String pattern = SettingsService.getInstance(project).getState().getFilePattern();
+        return file.getName().matches(pattern);
+    }
 }

src/main/java/de/marhali/easyi18n/util/JsonUtil.java

@@ -0,0 +1,83 @@
+package de.marhali.easyi18n.util;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonPrimitive;
+
+import de.marhali.easyi18n.model.LocalizedNode;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Json tree utilities for writing and reading {@link LocalizedNode}'s
+ * @author marhali
+ */
+public class JsonUtil {
+
+    /**
+     * Creates a {@link JsonObject} based from an {@link LocalizedNode}
+     * @param locale Current locale
+     * @param parent Parent json. Can be an entire json document
+     * @param node The node instance
+     */
+    public static void writeTree(String locale, JsonObject parent, LocalizedNode node) {
+        if(node.isLeaf() && !node.getKey().equals(LocalizedNode.ROOT_KEY)) {
+            if(node.getValue().get(locale) != null) {
+                parent.add(node.getKey(), new JsonPrimitive(node.getValue().get(locale)));
+            }
+
+        } else {
+            for(LocalizedNode children : node.getChildren()) {
+                if(children.isLeaf()) {
+                    writeTree(locale, parent, children);
+                } else {
+                    JsonObject childrenJson = new JsonObject();
+                    writeTree(locale, childrenJson, children);
+                    if(childrenJson.size() > 0) {
+                        parent.add(children.getKey(), childrenJson);
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Reads a {@link JsonObject} and writes the tree into the provided {@link LocalizedNode}
+     * @param locale Current locale
+     * @param json Json to read
+     * @param data Node. Can be a root node
+     */
+    public static void readTree(String locale, JsonObject json, LocalizedNode data) {
+        for(Map.Entry<String, JsonElement> entry : json.entrySet()) {
+            String key = entry.getKey();
+
+            try {
+                // Try to go one level deeper
+                JsonObject childObject = entry.getValue().getAsJsonObject();
+
+                LocalizedNode childrenNode = data.getChildren(key);
+
+                if(childrenNode == null) {
+                    childrenNode = new LocalizedNode(key, new ArrayList<>());
+                    data.addChildren(childrenNode);
+                }
+
+                readTree(locale, childObject, childrenNode);
+
+            } catch(IllegalStateException e) { // Reached end for this node
+                LocalizedNode leafNode = data.getChildren(key);
+
+                if(leafNode == null) {
+                    leafNode = new LocalizedNode(key, new HashMap<>());
+                    data.addChildren(leafNode);
+                }
+
+                Map<String, String> messages = leafNode.getValue();
+                messages.put(locale, entry.getValue().getAsString());
+                leafNode.setValue(messages);
+            }
+        }
+    }
+}

src/main/resources/META-INF/plugin.xml

@@ -10,5 +10,10 @@
     <extensions defaultExtensionNs="com.intellij">
         <toolWindow id="Easy I18n" anchor="bottom" factoryClass="de.marhali.easyi18n.TranslatorToolWindowFactory" />
         <projectService serviceImplementation="de.marhali.easyi18n.service.SettingsService" />
+
+        <completion.contributor language="any"
+                                implementationClass="de.marhali.easyi18n.ui.editor.I18nCompletionContributor" />
+
+        <annotator language="" implementationClass="de.marhali.easyi18n.ui.editor.I18nKeyAnnotator" />
     </extensions>
 </idea-plugin>

src/main/resources/messages.properties

@@ -13,4 +13,5 @@ translation.key=Key
 translation.locales=Locales
 settings.path.title=Locales Directory
 settings.path.text=Locales directory
+settings.path.file-pattern=Translation file pattern
 settings.preview=Preview locale