fix: revert transform behaviour and add CachedTransform

Author: ItsEmpa

common/src/main/kotlin/com/teamresourceful/resourcefulconfigkt/api/Entries.kt

@@ -42,24 +42,41 @@ class TransformedEntryDelegate<T, R> internal constructor(
 
     override val parent: RConfigKtEntry<R> = this
 
-    private var value: R = to(actualParent.get())
+    override var onChange: (R, R) -> Unit
+        get() = { p1, p2 -> actualParent.onChange(from(p1), from(p2)) }
+        set(value) {
+            actualParent.onChange = { p1, p2 -> value(to(p1), to(p2))}
+        }
+
+    override fun get(): R = to(actualParent.get())
+    override fun set(newValue: R) = actualParent.set(from(newValue))
+    override fun reset() = actualParent.reset()
+}
+
+class CachedTransformedEntryDelegate<T, R> internal constructor(
+    private val actualParent: RConfigKtEntry<T>,
+    private val from: (R) -> T,
+    private val to: (T) -> R,
+) : RConfigKtEntry<R> {
+
+    private var cached: R = to(actualParent.get())
+
+    override val parent: RConfigKtEntry<R> = this
 
     override var onChange: (R, R) -> Unit = { _, _ -> }
 
     init {
         val parentOnChange = actualParent.onChange
         actualParent.onChange = { old, new ->
             parentOnChange(old, new)
-            val oldValue = value
-            this.value = to(new)
-            if (oldValue != value) onChange(oldValue, value)
+            val oldValue = cached
+            this.cached = to(new)
+            if (oldValue != cached) onChange(oldValue, cached)
         }
     }
 
-    override fun get(): R = value
-
+    override fun get(): R = cached
     override fun set(newValue: R) = actualParent.set(from(newValue))
-
     override fun reset() = actualParent.reset()
 }
 
@@ -106,6 +123,17 @@ class ObservableEntry<T>(
     }
 }
 
+class CachedTransformedEntry<T, R>(
+    private val entry: ConfigDelegateProvider<RConfigKtEntry<T>>,
+    private val from: (R) -> T,
+    private val to: (T) -> R,
+) : ConfigDelegateProvider<RConfigKtEntry<R>> {
+    override operator fun provideDelegate(entries: EntriesBuilder, prop: KProperty<*>): CachedTransformedEntryDelegate<T, R> {
+        val property = entry.provideDelegate(entries, prop)
+        return CachedTransformedEntryDelegate(property.parent, from, to)
+    }
+}
+
 class TransformedEntry<T, R>(
     private val entry: ConfigDelegateProvider<RConfigKtEntry<T>>,
     private val from: (R) -> T,

common/src/main/kotlin/com/teamresourceful/resourcefulconfigkt/api/builders/EntriesBuilder.kt

@@ -4,6 +4,7 @@ import com.teamresourceful.resourcefulconfig.api.types.ResourcefulConfigElement
 import com.teamresourceful.resourcefulconfig.api.types.elements.ResourcefulConfigEntryElement
 import com.teamresourceful.resourcefulconfig.api.types.options.EntryType
 import com.teamresourceful.resourcefulconfig.api.types.options.TranslatableValue
+import com.teamresourceful.resourcefulconfigkt.api.CachedTransformedEntry
 import com.teamresourceful.resourcefulconfigkt.api.ConfigDelegateProvider
 import com.teamresourceful.resourcefulconfigkt.api.Entry
 import com.teamresourceful.resourcefulconfigkt.api.RConfigKtEntry
@@ -99,6 +100,8 @@ open class EntriesBuilder {
     fun <T> observable(entry: ConfigDelegateProvider<RConfigKtEntry<T>>, onChange: (T, T) -> Unit) = ObservableEntry(entry, onChange)
     fun <T, R> transform(entry: Entry<T, *>, from: (R) -> T, to: (T) -> R) = TransformedEntry(entry, from, to)
     fun <T, R> transform(entry: ConfigDelegateProvider<RConfigKtEntry<T>>, from: (R) -> T, to: (T) -> R) = TransformedEntry(entry, from, to)
+    fun <T, R> cachedTransform(entry: Entry<T, *>, from: (R) -> T, to: (T) -> R) = CachedTransformedEntry(entry, from, to)
+    fun <T, R> cachedTransform(entry: ConfigDelegateProvider<RConfigKtEntry<T>>, from: (R) -> T, to: (T) -> R) = CachedTransformedEntry(entry, from, to)
 
     companion object {