feat: added better fallback strategy

api/src/main/java/com/luminiadev/polyglot/api/Translation.java

@@ -3,9 +3,9 @@
 import com.luminiadev.polyglot.api.language.Language;
 import com.luminiadev.polyglot.api.parameter.TrParameters;
 import com.luminiadev.polyglot.api.parameter.formatter.TrParameterFormatter;
+import com.luminiadev.polyglot.api.util.FallbackStrategy;
 
 import java.util.Set;
-import java.util.function.Function;
 
 public interface Translation {
 
@@ -19,7 +19,7 @@ public interface Translation {
 
     void setDefaultLanguage(Language language);
 
-    void setFallbackStrategy(Function<String, String> fallbackFunction);
+    void setFallbackStrategy(FallbackStrategy fallbackStrategy);
 
     void addTranslation(Language language, String key, String value);
 

api/src/main/java/com/luminiadev/polyglot/api/util/FallbackStrategy.java

@@ -0,0 +1,65 @@
+package com.luminiadev.polyglot.api.util;
+
+/**
+ * Fallback strategy interface. Defines how to resolve missing keys.
+ */
+@FunctionalInterface
+public interface FallbackStrategy {
+
+    /**
+     * Resolves a value for the given key.
+     *
+     * @param key the key
+     * @return resolved value
+     */
+    String get(String key);
+
+    /**
+     * Returns the key itself.
+     *
+     * @return strategy returning the key
+     */
+    static FallbackStrategy keyToKey() {
+        return key -> key;
+    }
+
+    /**
+     * Returns a fixed default value.
+     *
+     * @param defaultValue default value
+     * @return strategy returning the default value
+     */
+    static FallbackStrategy defaultResult(String defaultValue) {
+        return key -> defaultValue;
+    }
+
+    /**
+     * Returns an empty string.
+     *
+     * @return strategy returning empty string
+     */
+    static FallbackStrategy emptyResult() {
+        return key -> "";
+    }
+
+    /**
+     * Returns the key with a prefix.
+     *
+     * @param prefix prefix to add
+     * @return strategy returning prefixed key
+     */
+    static FallbackStrategy prefix(String prefix) {
+        return key -> prefix + key;
+    }
+
+    /**
+     * Returns the key with a suffix.
+     *
+     * @param suffix suffix to add
+     * @return strategy returning suffixed key
+     */
+    static FallbackStrategy suffix(String suffix) {
+        return key -> key + suffix;
+    }
+}
+

build.gradle.kts

@@ -12,7 +12,7 @@ java {
 
 allprojects {
     group = "com.luminiadev.polyglot"
-    version = "1.0.3-SNAPSHOT"
+    version = "1.0.4-SNAPSHOT"
 }
 
 subprojects {

core/src/main/java/com/luminiadev/polyglot/core/BaseTranslation.java

@@ -1,5 +1,6 @@
 package com.luminiadev.polyglot.core;
 
+import com.luminiadev.polyglot.api.util.FallbackStrategy;
 import com.luminiadev.polyglot.api.Translation;
 import com.luminiadev.polyglot.api.context.TranslationContext;
 import com.luminiadev.polyglot.api.language.Language;
@@ -15,7 +16,6 @@
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
-import java.util.function.Function;
 
 /**
  * Base implementation of the translation.
@@ -27,7 +27,7 @@ public class BaseTranslation implements Translation {
     private final Map<Class<? extends TrParameters>, TrParameterFormatter> formatters;
 
     private Language defaultLanguage;
-    private Function<String, String> fallbackStrategy;
+    private FallbackStrategy fallbackStrategy;
 
     public BaseTranslation(TranslationContext context, TranslationProvider provider) {
         this.context = context;
@@ -164,7 +164,7 @@ public void setDefaultLanguage(Language language) {
     }
 
     @Override
-    public void setFallbackStrategy(Function<String, String> fallbackStrategy) {
+    public void setFallbackStrategy(FallbackStrategy fallbackStrategy) {
         this.fallbackStrategy = fallbackStrategy;
     }