1 files changed, 105 insertions, 0 deletions
diff --git a/src/LispData.kt b/src/LispData.kt
new file mode 100644
index 0000000..1f13ad3
--- /dev/null
+++ b/src/LispData.kt
@@ -0,0 +1,105 @@
+package moe.nea.lisp
+
+sealed class LispData {
+
+    fun <T : Any> lispCastObject(lClass: LispClass<T>): LispObject<T>? {
+        if (this !is LispObject<*>) return null
+        if (this.handler != lClass) return null
+        return this as LispObject<T>
+    }
+
+    object LispNil : LispData()
+    data class Atom(val label: String) : LispData()
+    data class LispNode(val node: LispAst.LispNode) : LispData()
+    data class LispNumber(val number: Double) : LispData()
+    data class LispObject<T : Any>(val data: T, val handler: LispClass<T>) : LispData()
+    sealed class LispExecutable() : LispData() {
+        abstract fun execute(
+            executionContext: LispExecutionContext,
+            callsite: LispAst.LispNode,
+            stackFrame: StackFrame,
+            args: List<LispAst.LispNode>
+        ): LispData
+    }
+
+
+    abstract class JavaExecutable : LispExecutable() {
+    }
+
+    data class LispInterpretedCallable(
+        val declarationStackFrame: StackFrame,
+        val argNames: List<String>,
+        val body: LispAst.Parenthesis,
+        val name: String?,
+    ) : LispExecutable() {
+        override fun execute(
+            executionContext: LispExecutionContext,
+            callsite: LispAst.LispNode,
+            stackFrame: StackFrame,
+            args: List<LispAst.LispNode>
+        ): LispData {
+            if (argNames.size != args.size) {
+                TODO("ERROR")
+            }
+            val invocationFrame = declarationStackFrame.fork()
+
+            for ((name, value) in argNames.zip(args)) {
+                invocationFrame.setValueLocal(name, executionContext.resolveValue(stackFrame, value))
+            }
+            return executionContext.executeLisp(invocationFrame, body)
+        }
+    }
+
+    interface LispClass<T : Any> {
+        fun access(obj: T, name: String): LispData
+        fun instantiate(obj: T) = LispObject(obj, this)
+    }
+
+    object LispStringClass : LispClass<String> {
+        override fun access(obj: String, name: String): LispData {
+            return LispNil
+        }
+    }
+
+    companion object {
+        fun string(value: String): LispObject<String> =
+            LispStringClass.instantiate(value)
+
+        fun externalRawCall(callable: (context: LispExecutionContext, callsite: LispAst.LispNode, stackFrame: StackFrame, args: List<LispAst.LispNode>) -> LispData): LispExecutable {
+            return object : JavaExecutable() {
+                override fun execute(
+                    executionContext: LispExecutionContext,
+                    callsite: LispAst.LispNode,
+                    stackFrame: StackFrame,
+                    args: List<LispAst.LispNode>
+                ): LispData {
+                    return callable.invoke(executionContext, callsite, stackFrame, args)
+                }
+            }
+        }
+
+        fun externalCall(callable: (args: List<LispData>, reportError: (String) -> LispData) -> LispData): LispExecutable {
+            return object : JavaExecutable() {
+                override fun execute(
+                    executionContext: LispExecutionContext,
+                    callsite: LispAst.LispNode,
+                    stackFrame: StackFrame,
+                    args: List<LispAst.LispNode>
+                ): LispData {
+                    val mappedArgs = args.map { executionContext.resolveValue(stackFrame, it) }
+                    return callable.invoke(mappedArgs) { executionContext.reportError(it, callsite) }
+                }
+            }
+        }
+
+
+        fun createLambda(
+            declarationStackFrame: StackFrame,
+            args: List<String>,
+            body: LispAst.Parenthesis,
+            nameHint: String? = null,
+        ): LispExecutable {
+            return LispInterpretedCallable(declarationStackFrame, args, body, nameHint)
+        }
+    }
+}