Fix scheme initialization

dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataFilter.kt

@@ -44,7 +44,7 @@ public fun <T : Any> DataNode<T>.filter(filter: DataFilter): DataNode<T> {
 /**
  * Filter data using [DataFilter] specification
  */
-public fun <T : Any> DataNode<T>.filter(filter: Meta): DataNode<T> = filter(DataFilter.wrap(filter))
+public fun <T : Any> DataNode<T>.filter(filter: Meta): DataNode<T> = filter(DataFilter.read(filter))
 
 /**
  * Filter data using [DataFilter] builder

dataforge-io/src/commonMain/kotlin/hep/dataforge/io/EnvelopeParts.kt

@@ -88,7 +88,7 @@ public fun Envelope.parts(): EnvelopeParts {
     if (data == null) return emptyList()
     //TODO add zip folder reader
     val parts = meta.getIndexed(PARTS_KEY).values.mapNotNull { it.node }.map {
-        PartDescriptor.wrap(it)
+        PartDescriptor.read(it)
     }
     return if (parts.isEmpty()) {
         listOf(EnvelopePart(data!!, meta[MULTIPART_KEY].node))

dataforge-meta/api/dataforge-meta.api

@@ -493,10 +493,16 @@ public final class hep/dataforge/meta/SchemeKt {
 public class hep/dataforge/meta/SchemeSpec : hep/dataforge/meta/Specification, hep/dataforge/meta/descriptors/Described {
 	public fun <init> (Lkotlin/jvm/functions/Function0;)V
 	public fun <init> (Lkotlin/jvm/functions/Function3;)V
+	public synthetic fun empty ()Lhep/dataforge/meta/MutableItemProvider;
+	public fun empty ()Lhep/dataforge/meta/Scheme;
 	public synthetic fun getDescriptor ()Lhep/dataforge/meta/descriptors/ItemDescriptor;
 	public fun getDescriptor ()Lhep/dataforge/meta/descriptors/NodeDescriptor;
-	public synthetic fun wrap (Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
+	public synthetic fun invoke (Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/MutableItemProvider;
-	public fun wrap (Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/Scheme;
+	public final fun invoke (Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/Scheme;
+	public synthetic fun read (Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
+	public fun read (Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/Scheme;
+	public synthetic fun wrap (Lhep/dataforge/meta/Config;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
+	public fun wrap (Lhep/dataforge/meta/Config;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/Scheme;
 }
 
 public final class hep/dataforge/meta/SealedMeta : hep/dataforge/meta/AbstractMetaNode {
@@ -504,19 +510,24 @@ public final class hep/dataforge/meta/SealedMeta : hep/dataforge/meta/AbstractMe
 }
 
 public abstract interface class hep/dataforge/meta/Specification {
-	public abstract fun wrap (Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
+	public abstract fun empty ()Lhep/dataforge/meta/MutableItemProvider;
+	public abstract fun invoke (Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/MutableItemProvider;
+	public abstract fun read (Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
+	public abstract fun wrap (Lhep/dataforge/meta/Config;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
 }
 
 public final class hep/dataforge/meta/Specification$DefaultImpls {
-	public static synthetic fun wrap$default (Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;ILjava/lang/Object;)Lhep/dataforge/meta/MutableItemProvider;
+	public static fun empty (Lhep/dataforge/meta/Specification;)Lhep/dataforge/meta/MutableItemProvider;
+	public static fun invoke (Lhep/dataforge/meta/Specification;Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/MutableItemProvider;
+	public static synthetic fun read$default (Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Meta;Lhep/dataforge/meta/ItemProvider;ILjava/lang/Object;)Lhep/dataforge/meta/MutableItemProvider;
+	public static fun wrap (Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Config;Lhep/dataforge/meta/ItemProvider;)Lhep/dataforge/meta/MutableItemProvider;
+	public static synthetic fun wrap$default (Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Config;Lhep/dataforge/meta/ItemProvider;ILjava/lang/Object;)Lhep/dataforge/meta/MutableItemProvider;
 }
 
 public final class hep/dataforge/meta/SpecificationKt {
 	public static final fun configSpec (Lhep/dataforge/meta/MetaItem;Lhep/dataforge/meta/Specification;)Lhep/dataforge/meta/MutableItemProvider;
 	public static final fun configure (Lhep/dataforge/meta/MetaRepr;Lhep/dataforge/meta/Specification;Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/MetaRepr;
 	public static final fun createStyle (Lhep/dataforge/meta/Specification;Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/Meta;
-	public static final fun empty (Lhep/dataforge/meta/Specification;)Lhep/dataforge/meta/MutableItemProvider;
-	public static final fun invoke (Lhep/dataforge/meta/Specification;Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/MutableItemProvider;
 	public static final fun spec (Lhep/dataforge/meta/MetaItem;Lhep/dataforge/meta/Specification;)Lhep/dataforge/meta/MutableItemProvider;
 	public static final fun spec (Lhep/dataforge/meta/MutableItemProvider;Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Scheme;Lhep/dataforge/names/Name;)Lkotlin/properties/ReadWriteProperty;
 	public static final fun spec (Lhep/dataforge/meta/MutableItemProvider;Lhep/dataforge/meta/Specification;Lhep/dataforge/names/Name;)Lkotlin/properties/ReadWriteProperty;
@@ -524,7 +535,6 @@ public final class hep/dataforge/meta/SpecificationKt {
 	public static synthetic fun spec$default (Lhep/dataforge/meta/MutableItemProvider;Lhep/dataforge/meta/Specification;Lhep/dataforge/names/Name;ILjava/lang/Object;)Lkotlin/properties/ReadWriteProperty;
 	public static final fun update (Lhep/dataforge/meta/Configurable;Lhep/dataforge/meta/Specification;Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/Configurable;
 	public static final fun update (Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Meta;Lkotlin/jvm/functions/Function1;)Lhep/dataforge/meta/MutableItemProvider;
-	public static final fun wrap (Lhep/dataforge/meta/Specification;Lhep/dataforge/meta/Meta;)Lhep/dataforge/meta/MutableItemProvider;
 }
 
 public abstract interface class hep/dataforge/meta/descriptors/Described {

dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/Scheme.kt

@@ -16,7 +16,10 @@ public open class Scheme(
 ) : Configurable, MutableItemProvider, Described, MetaRepr {
 
     override var config: Config = config
-        internal set
+        internal set(value) {
+            //Fix problem with `init` blocks in specifications
+            field = value.apply { update(field) }
+        }
 
     override var descriptor: NodeDescriptor? = descriptor
         internal set
@@ -94,17 +97,18 @@ public open class SchemeSpec<T : Scheme>(
         }
     })
 
-    /**
+    override fun read(meta: Meta, defaultProvider: ItemProvider): T =
-     * If the provided [Meta] is a [Config] use it as a scheme base, otherwise use it as default.
-     */
-    override fun wrap(meta: Meta, defaultProvider: ItemProvider): T = if (meta is Config) {
-        builder(meta, defaultProvider, descriptor)
-    } else {
         builder(Config(), meta.withDefault(defaultProvider), descriptor)
+
+    override fun wrap(config: Config, defaultProvider: ItemProvider): T {
+        return builder(config, defaultProvider, descriptor)
     }
 
     //TODO Generate descriptor from Scheme class
     override val descriptor: NodeDescriptor? get() = null
+
+    @Suppress("OVERRIDE_BY_INLINE")
+    final override inline operator fun invoke(action: T.() -> Unit): T = empty().apply(action)
 }
 
 ///**
@@ -118,7 +122,9 @@ public open class SchemeSpec<T : Scheme>(
 //    override val defaultLayer: Meta get() = Laminate(meta, descriptor?.defaultItem().node)
 //}
 
-public fun Meta.asScheme(): Scheme = Scheme(this.asConfig(), null, null)
+public fun Meta.asScheme(): Scheme = Scheme().apply {
+    config = this@asScheme.asConfig()
+}
 
 public fun <T : MutableItemProvider> Meta.toScheme(spec: Specification<T>, block: T.() -> Unit = {}): T =
-    spec.wrap(this).apply(block)
+    spec.read(this).apply(block)

dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/Specification.kt

@@ -13,27 +13,33 @@ import kotlin.reflect.KProperty
  */
 public interface Specification<T : MutableItemProvider> {
     /**
-     * Wrap generic configuration producing instance of desired type
+     * Read generic read-only meta with this [Specification] producing instance of desired type.
      */
-    public fun wrap(meta: Meta, defaultProvider: ItemProvider = ItemProvider.EMPTY): T
+    public fun read(meta: Meta, defaultProvider: ItemProvider = ItemProvider.EMPTY): T
+
+    /**
+     * Wrap mutable [Config], using it as inner storage (changes to [Specification] are reflected on [Config]
+     */
+    public fun wrap(config: Config, defaultProvider: ItemProvider = ItemProvider.EMPTY): T =
+        read(config as Meta, defaultProvider)
+
+    /**
+     * Generate an empty object
+     */
+    public fun empty(): T = read(Meta.EMPTY)
+
+    /**
+     * A convenience method to use specifications in builders
+     */
+    public operator fun invoke(action: T.() -> Unit): T = empty().apply(action)
 }
 
-public fun <T : MutableItemProvider> Specification<T>.empty(): T = wrap(Config())
-
-public inline operator fun <T : MutableItemProvider> Specification<T>.invoke(action: T.() -> Unit): T = empty().apply(action)
-
 /**
  * Update given configuration using given type as a builder
  */
-public fun <T : MutableItemProvider> Specification<T>.update(meta: Meta, action: T.() -> Unit): T = wrap(meta).apply(action)
+public fun <T : MutableItemProvider> Specification<T>.update(meta: Meta, action: T.() -> Unit): T =
+    read(meta).apply(action)
 
-/**
- * Create a read-only version of
- */
-public fun <T : MutableItemProvider> Specification<T>.wrap(source: Meta): T {
-    val default = source.seal()
-    return wrap(source.asConfig(), default)
-}
 
 /**
  * Apply specified configuration to configurable
@@ -44,7 +50,10 @@ public fun <T : MetaRepr, C : MutableItemProvider, S : Specification<C>> T.confi
 /**
  * Update configuration using given specification
  */
-public fun <C : MutableItemProvider, S : Specification<C>> Configurable.update(spec: S, action: C.() -> Unit): Configurable =
+public fun <C : MutableItemProvider, S : Specification<C>> Configurable.update(
+    spec: S,
+    action: C.() -> Unit,
+): Configurable =
     apply { spec.update(config, action) }
 
 /**
@@ -63,11 +72,11 @@ public fun <T : MutableItemProvider> MetaItem<*>.spec(spec: Specification<T>): T
 public fun <T : MutableItemProvider> MetaItem<Config>.spec(spec: Specification<T>): T? = node?.let { spec.wrap(it) }
 
 public fun <T : Scheme> MutableItemProvider.spec(
-    spec: Specification<T>, key: Name? = null
+    spec: Specification<T>, key: Name? = null,
 ): ReadWriteProperty<Any?, T?> = object : ReadWriteProperty<Any?, T?> {
     override fun getValue(thisRef: Any?, property: KProperty<*>): T? {
         val name = key ?: property.name.asName()
-        return getItem(name).node?.let { spec.wrap(it) }
+        return getItem(name).node?.let { spec.read(it) }
     }
 
     override fun setValue(thisRef: Any?, property: KProperty<*>, value: T?) {
@@ -79,11 +88,11 @@ public fun <T : Scheme> MutableItemProvider.spec(
 public fun <T : Scheme> MutableItemProvider.spec(
     spec: Specification<T>,
     default: T,
-    key: Name? = null
+    key: Name? = null,
 ): ReadWriteProperty<Any?, T> = object : ReadWriteProperty<Any?, T> {
     override fun getValue(thisRef: Any?, property: KProperty<*>): T {
         val name = key ?: property.name.asName()
-        return getItem(name).node?.let { spec.wrap(it) } ?: default
+        return getItem(name).node?.let { spec.read(it) } ?: default
     }
 
     override fun setValue(thisRef: Any?, property: KProperty<*>, value: T) {

dataforge-meta/src/commonTest/kotlin/hep/dataforge/meta/SpecificationTest.kt

@@ -4,13 +4,15 @@ import kotlin.test.Test
 import kotlin.test.assertEquals
 
 class SpecificationTest {
-    class TestStyled(config: Config, defaultProvider: ItemProvider) :
+    class TestStyled : Scheme() {
-        Scheme(config, defaultProvider) {
         var list by numberList(1, 2, 3)
 
         companion object : Specification<TestStyled> {
-            override fun wrap(meta: Meta, defaultProvider: ItemProvider): TestStyled =
+            override fun read(meta: Meta, defaultProvider: ItemProvider): TestStyled =
-                TestStyled(meta.asConfig(), defaultProvider)
+                TestStyled().apply {
+                    this.config = meta.asConfig()
+
+                }
         }
     }