Add GGUF paremeters loader for fixing the local build

Author: michalharakal

io/build.gradle.kts

@@ -31,6 +31,7 @@ kotlin {
         val commonMain by getting {
             dependencies {
                 implementation(project(":core"))
+                implementation(project(":gguf"))
                 implementation(libs.kotlinx.io.core)
 
                 implementation(libs.kotlinx.serialization.json)

io/src/commonMain/kotlin/sk/ai/net/io/gguf/GGUFParametersLoader.kt

@@ -0,0 +1,46 @@
+package sk.ai.net.io.gguf
+
+import kotlinx.io.Source
+import sk.ai.net.Shape
+import sk.ai.net.Tensor
+import sk.ai.net.impl.DoublesTensor
+import sk.ai.net.io.ParametersLoader
+import sk.ai.net.gguf.GGUFReader
+import sk.ai.net.gguf.GGMLQuantizationType
+
+/**
+ * A parameters loader that loads tensors from a GGUF file.
+ *
+ * @param handleSource A function that returns a Source for the GGUF file.
+ */
+class GGUFParametersLoader(private val handleSource: () -> Source) : ParametersLoader {
+    override suspend fun load(onTensorLoaded: (String, Tensor) -> Unit) {
+        handleSource().use { source ->
+            val reader = GGUFReader(source)
+
+            // Process each tensor in the GGUF file
+            reader.tensors.forEach { tensor ->
+                // Convert the tensor data to a DoublesTensor
+                val shapeArray = tensor.shape.map { it.toInt() }.toIntArray()
+                val shape = Shape(*shapeArray)
+
+                // Convert the tensor data to a DoubleArray
+                val doubleValues = when (tensor.tensorType) {
+                    GGMLQuantizationType.F32 -> (tensor.data as List<*>).map { (it as Float).toDouble() }.toDoubleArray()
+                    GGMLQuantizationType.F64 -> (tensor.data as List<*>).map { it as Double }.toDoubleArray()
+                    GGMLQuantizationType.I8 -> (tensor.data as List<*>).map { (it as Byte).toDouble() }.toDoubleArray()
+                    GGMLQuantizationType.I16 -> (tensor.data as List<*>).map { (it as Short).toDouble() }.toDoubleArray()
+                    GGMLQuantizationType.I32 -> (tensor.data as List<*>).map { (it as Int).toDouble() }.toDoubleArray()
+                    GGMLQuantizationType.I64 -> (tensor.data as List<*>).map { (it as Long).toDouble() }.toDoubleArray()
+                    else -> throw IllegalArgumentException("Unsupported tensor type: ${tensor.tensorType}")
+                }
+
+                // Create a DoublesTensor with the shape and values
+                val doublesTensor = DoublesTensor(shape, doubleValues)
+
+                // Call the callback with the tensor name and the DoublesTensor
+                onTensorLoaded(tensor.name, doublesTensor)
+            }
+        }
+    }
+}