Laminate refactor

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/Laminate.kt

@@ -8,26 +8,24 @@ import space.kscience.dataforge.values.Value
  * A meta laminate consisting of multiple immutable meta layers. For mutable front layer, use [Scheme].
  * If [layers] list contains a [Laminate] it is flat-mapped.
  */
-public class Laminate(layers: List<Meta>) : TypedMeta<SealedMeta> {
+public class Laminate internal constructor(public val layers: List<Meta>) : TypedMeta<Laminate> {
 
     override val value: Value? = layers.firstNotNullOfOrNull { it.value }
 
-    public val layers: List<Meta> = layers.flatMap {
+    override val items: Map<NameToken, Laminate> by lazy {
-        if (it is Laminate) {
+        layers.map { it.items.keys }.flatten().associateWith { key ->
-            it.layers
+            Laminate(layers.mapNotNull { it.items[key] })
-        } else {
-            listOf(it)
         }
     }
 
-    override val items: Map<NameToken, SealedMeta> by lazy {
+    override fun getMeta(name: Name): Laminate? {
-        layers.map { it.items.keys }.flatten().associateWith { key ->
+        val childLayers = layers.mapNotNull { it.getMeta(name) }
-            layers.asSequence().map { it.items[key] }.filterNotNull().let(replaceRule)
+        return if (childLayers.isEmpty()) null else Laminate(childLayers)
-        }
     }
 
     /**
-     * Generate sealed meta using [mergeRule]
+     * Generate sealed meta by interweaving all layers. If a value is present in at least on layer, it will be present
+     * in the result.
      */
     public fun merge(): SealedMeta {
         val items = layers.map { it.items.keys }.flatten().associateWith { key ->
@@ -36,6 +34,17 @@ public class Laminate(layers: List<Meta>) : TypedMeta<SealedMeta> {
         return SealedMeta(value, items)
     }
 
+    /**
+     * Generate sealed meta by stacking layers. If node is present in the upper layer, then the lower layers will be
+     * ignored event if they have values that are not present on top layer.
+     */
+    public fun top(): SealedMeta {
+        val items = layers.map { it.items.keys }.flatten().associateWith { key ->
+            layers.asSequence().map { it.items[key] }.filterNotNull().first().seal()
+        }
+        return SealedMeta(value, items)
+    }
+
     override fun toString(): String = Meta.toString(this)
     override fun equals(other: Any?): Boolean = Meta.equals(this, other as? Meta)
     override fun hashCode(): Int = Meta.hashCode(this)
@@ -47,7 +56,7 @@ public class Laminate(layers: List<Meta>) : TypedMeta<SealedMeta> {
          *
          * TODO add picture
          */
-        public val replaceRule: (Sequence<Meta>) -> SealedMeta = { it.first().seal() }
+        public val replaceRule: (Sequence<Meta>) -> SealedMeta? = { it.firstOrNull()?.seal() }
 
         private fun Sequence<Meta>.merge(): SealedMeta {
             val value = firstNotNullOfOrNull { it.value }
@@ -69,12 +78,22 @@ public class Laminate(layers: List<Meta>) : TypedMeta<SealedMeta> {
          * The values a replaced but meta children are joined
          * TODO add picture
          */
-        public val mergeRule: (Sequence<Meta>) -> TypedMeta<SealedMeta> = { it.merge() }
+        public val mergeRule: (Sequence<Meta>) -> SealedMeta? = { it.merge() }
     }
 }
 
-@Suppress("FunctionName")
+public fun Laminate(layers: Collection<Meta?>): Laminate {
-public fun Laminate(vararg layers: Meta?): Laminate = Laminate(layers.filterNotNull())
+    val flatLayers = layers.flatMap {
+        if (it is Laminate) {
+            it.layers
+        } else {
+            listOf(it)
+        }
+    }.filterNotNull()
+    return Laminate(flatLayers)
+}
+
+public fun Laminate(vararg layers: Meta?): Laminate = Laminate(listOf(*layers))
 
 /**
  * Performance optimized version of get method

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/Meta.kt

@@ -144,9 +144,18 @@ public interface TypedMeta<out M : TypedMeta<M>> : Meta {
     public val self: M
         get() = this as M
 
-    override val value: Value?
     override val items: Map<NameToken, M>
 
+    override fun getMeta(name: Name): M? {
+        tailrec fun M.find(name: Name): M? = if (name.isEmpty()) {
+            this
+        } else {
+            items[name.firstOrNull()!!]?.find(name.cutFirst())
+        }
+
+        return self.find(name)
+    }
+
     override fun toMeta(): Meta = this
 }
 

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/MutableMeta.kt

@@ -1,6 +1,7 @@
 package space.kscience.dataforge.meta
 
 import kotlinx.serialization.Serializable
+import space.kscience.dataforge.misc.DFExperimental
 import space.kscience.dataforge.names.*
 import space.kscience.dataforge.values.EnumValue
 import space.kscience.dataforge.values.Value
@@ -154,8 +155,9 @@ public interface MutableTypedMeta<M : MutableTypedMeta<M>> : TypedMeta<M>, Mutab
      * Zero-copy attach or replace existing node. Node is used with any additional state, listeners, etc.
      * In some cases it is possible to have the same node as a child to several others
      */
+    @DFExperimental
     public fun attach(name: Name, node: M)
-
+    override fun getMeta(name: Name): M?
     override fun getOrCreate(name: Name): M
 }
 
@@ -298,13 +300,13 @@ private class MutableMetaImpl(
         listeners.removeAll { it.owner === owner }
     }
 
-
     private fun ObservableMeta.adoptBy(parent: MutableMetaImpl, key: NameToken) {
         onChange(parent) { name ->
             parent.invalidate(key + name)
         }
     }
 
+    @DFExperimental
     override fun attach(name: Name, node: ObservableMutableMeta) {
         when (name.length) {
             0 -> error("Can't set a meta with empty name")

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/ObservableMeta.kt

@@ -1,5 +1,6 @@
 package space.kscience.dataforge.meta
 
+import space.kscience.dataforge.misc.DFExperimental
 import space.kscience.dataforge.names.*
 import space.kscience.dataforge.values.Value
 import kotlin.jvm.Synchronized
@@ -34,7 +35,20 @@ public interface ObservableMeta : Meta {
 /**
  * A [Meta] which is both observable and mutable
  */
-public interface ObservableMutableMeta : ObservableMeta, MutableMeta, MutableTypedMeta<ObservableMutableMeta>
+public interface ObservableMutableMeta : ObservableMeta, MutableMeta, MutableTypedMeta<ObservableMutableMeta>{
+    override fun getOrCreate(name: Name): ObservableMutableMeta
+
+
+    override fun getMeta(name: Name): ObservableMutableMeta?{
+        tailrec fun ObservableMutableMeta.find(name: Name): ObservableMutableMeta? = if (name.isEmpty()) {
+            this
+        } else {
+            items[name.firstOrNull()!!]?.find(name.cutFirst())
+        }
+
+        return find(name)
+    }
+}
 
 private class ObservableMetaWrapper(
     val origin: MutableMeta,
@@ -59,7 +73,7 @@ private class ObservableMetaWrapper(
     override val items: Map<NameToken, ObservableMetaWrapper>
         get() = origin.items.mapValues { ObservableMetaWrapper(it.value) }
 
-    override fun getMeta(name: Name): MutableMeta? = origin.getMeta(name)
+    override fun getMeta(name: Name): ObservableMetaWrapper? = origin.getMeta(name)?.let{ObservableMetaWrapper(it)}
 
     override var value: Value?
         get() = origin.value
@@ -91,6 +105,7 @@ private class ObservableMetaWrapper(
         return origin.toMeta()
     }
 
+    @DFExperimental
     override fun attach(name: Name, node: ObservableMutableMeta) {
         set(name, node)
         node.onChange(this) { changeName ->

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/SealedMeta.kt

@@ -8,7 +8,6 @@ import space.kscience.dataforge.values.asValue
 /**
  * The meta implementation which is guaranteed to be immutable.
  *
- * If the argument is possibly mutable node, it is copied on creation
  */
 @Serializable
 public class SealedMeta internal constructor(
@@ -21,7 +20,7 @@ public class SealedMeta internal constructor(
 }
 
 /**
- * Generate sealed node from [this]. If it is already sealed return it as is
+ * Generate sealed node from [this]. If it is already sealed return it as is.
  */
 public fun Meta.seal(): SealedMeta = this as? SealedMeta ?: SealedMeta(
     value,

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/names/Name.kt

@@ -195,7 +195,7 @@ public fun Name.endsWith(name: Name): Boolean =
     this.length >= name.length && (this == name || tokens.subList(length - name.length, length) == name.tokens)
 
 /**
- * if [this] starts with given [head] name, returns the reminder of the name (could be empty). Otherwise returns null
+ * if [this] starts with given [head] name, returns the reminder of the name (could be empty). Otherwise, returns null
  */
 public fun Name.removeHeadOrNull(head: Name): Name? = if (startsWith(head)) {
     Name(tokens.subList(head.length, length))