package de.dhbwstuttgart.bytecode;

import java.awt.List;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;

import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

import de.dhbwstuttgart.parser.SyntaxTreeGenerator.AssignToLocal;
import de.dhbwstuttgart.syntaxtree.*;
import de.dhbwstuttgart.syntaxtree.statement.ArgumentList;
import de.dhbwstuttgart.syntaxtree.statement.Assign;
import de.dhbwstuttgart.syntaxtree.statement.AssignToField;
import de.dhbwstuttgart.syntaxtree.statement.Binary;
import de.dhbwstuttgart.syntaxtree.statement.Block;
import de.dhbwstuttgart.syntaxtree.statement.CastExpr;
import de.dhbwstuttgart.syntaxtree.statement.DoStmt;
import de.dhbwstuttgart.syntaxtree.statement.EmptyStmt;
import de.dhbwstuttgart.syntaxtree.statement.FieldVar;
import de.dhbwstuttgart.syntaxtree.statement.ForStmt;
import de.dhbwstuttgart.syntaxtree.statement.IfStmt;
import de.dhbwstuttgart.syntaxtree.statement.InstanceOf;
import de.dhbwstuttgart.syntaxtree.statement.LambdaExpression;
import de.dhbwstuttgart.syntaxtree.statement.LocalVar;
import de.dhbwstuttgart.syntaxtree.statement.LocalVarDecl;
import de.dhbwstuttgart.syntaxtree.statement.MethodCall;
import de.dhbwstuttgart.syntaxtree.statement.NewArray;
import de.dhbwstuttgart.syntaxtree.statement.NewClass;
import de.dhbwstuttgart.syntaxtree.statement.Receiver;
import de.dhbwstuttgart.syntaxtree.statement.Return;
import de.dhbwstuttgart.syntaxtree.statement.ReturnVoid;
import de.dhbwstuttgart.syntaxtree.statement.StaticClassName;
import de.dhbwstuttgart.syntaxtree.statement.Super;
import de.dhbwstuttgart.syntaxtree.statement.SuperCall;
import de.dhbwstuttgart.syntaxtree.statement.This;
import de.dhbwstuttgart.syntaxtree.statement.UnaryPlus;
import de.dhbwstuttgart.syntaxtree.statement.WhileStmt;
import de.dhbwstuttgart.syntaxtree.statement.literal.Literal;
import de.dhbwstuttgart.syntaxtree.statement.literal.Null;
import de.dhbwstuttgart.syntaxtree.type.ExtendsWildcardType;
import de.dhbwstuttgart.syntaxtree.type.GenericRefType;
import de.dhbwstuttgart.syntaxtree.type.RefType;
import de.dhbwstuttgart.syntaxtree.type.SuperWildcardType;
import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;

public class BytecodeGen implements ASTVisitor {
	
	ClassWriter cw =new ClassWriter(ClassWriter.COMPUTE_FRAMES|ClassWriter.COMPUTE_MAXS);
//	String methDesc;
	
	String type;
	
	String className;
	
	// stores parameter, local vars and the next index on the local variable table, which use for aload_i, astore_i,...
	HashMap<String, Integer> paramsAndLocals;// = new HashMap<>();
	byte[] bytecode;
	HashMap<String,byte[]> classFiles;
	
	public BytecodeGen(HashMap<String,byte[]> classFiles) {
		this.classFiles = classFiles;
		paramsAndLocals = new HashMap<>();
	}
	
	@Override
	public void visit(SourceFile sourceFile) {
		for(ClassOrInterface cl : sourceFile.getClasses()) {
			BytecodeGen classGen = new BytecodeGen(classFiles);
			cl.accept(classGen);
			classGen.writeClass(cl.getClassName().toString());
		}
	}

	private void writeClass(String name) {
		bytecode = cw.toByteArray();
		classFiles.put(name, bytecode);
		
	}
	
	public HashMap<String,byte[]> getClassFiles() {
		return classFiles;
	}
	@Override
	public void visit(ClassOrInterface classOrInterface) {
		className = classOrInterface.getClassName().toString();
		// access flages??
		cw.visit(Opcodes.V1_8, classOrInterface.getModifiers()+Opcodes.ACC_SUPER, classOrInterface.getClassName().toString()
				, null, classOrInterface.getSuperClass().toString(), null);
		
		// for each field in the class
		for(Field f : classOrInterface.getFieldDecl()) {
			System.out.println("get Fields");
			System.out.println(f.getName());
			f.accept(this);
		}
		
		for(Constructor c : classOrInterface.getConstructors()) {
			c.accept(this);
		}
		
		for(Method m : classOrInterface.getMethods()) {
			m.accept(this);
		}
		cw.visitSource(classOrInterface.getClassName().toString()+".jav", null);
	}
	
	@Override
	public void visit(Constructor field) {
		Descriptor desc = new Descriptor(field);
		MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", desc.getDesc(), null, null); 
		mv.visitCode();		
		System.out.println("-----Constructor-----");
		BytecodeGenMethod gen = new BytecodeGenMethod(className,field, mv,paramsAndLocals,desc.getDesc(),cw);

		mv.visitInsn(Opcodes.RETURN);
		mv.visitMaxs(0, 0);
		mv.visitEnd();
	}

	@Override
	public void visit(Method method) {
		method.getParameterList().accept(this);
		Descriptor methDesc = new Descriptor(method);
		System.out.println("-----Method-----");
		MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, method.getName(), methDesc.getDesc(), null, null); 
		mv.visitCode();		
		
		BytecodeGenMethod gen = new BytecodeGenMethod(className,method, mv,paramsAndLocals,methDesc.getDesc(),cw);
		mv.visitMaxs(0, 0);
		mv.visitEnd();
	}
	
	@Override
	public void visit(ParameterList formalParameters) {
		Iterator<FormalParameter> itr = formalParameters.iterator();
		int i = 1;
		while(itr.hasNext()) {
			FormalParameter fp = itr.next();
			paramsAndLocals.put(fp.getName(), i);
			fp.accept(this);
			i++;
		}
	}
	
	@Override
	public void visit(FormalParameter formalParameter) {
		formalParameter.getType().accept(this);
	}
	
	@Override
	public void visit(RefType refType) {
		type = "L"+refType.toString()+";";
	}

	@Override
	public void visit(SuperWildcardType superWildcardType) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(TypePlaceholder typePlaceholder) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(ExtendsWildcardType extendsWildcardType) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(GenericRefType genericRefType) {
		// TODO Auto-generated method stub
		
	}

	// ??
	@Override
	public void visit(FieldVar fieldVar) {
		System.out.println("in fieldvar");
//		cw.newField(fieldVar.receiver.toString(), fieldVar.fieldVarName.toString(), fieldVar.getType().toString());
		FieldVisitor fv = cw.visitField(Opcodes.ACC_PRIVATE, fieldVar.fieldVarName, "L"+fieldVar.getType()+";", null, null);
		fv.visitEnd();
	}
	
	// access flages?? modifiers
	@Override
	public void visit(Field field) {
		System.out.println("in field");
		FieldVisitor fv = cw.visitField(Opcodes.ACC_PRIVATE, field.getName(), "L"+field.getType().toString().replace(".", "/")+";", null, null);
		fv.visitEnd();
	}

	@Override
	public void visit(LambdaExpression lambdaExpression) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Assign assign) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Binary binary) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Block block) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(CastExpr castExpr) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(EmptyStmt emptyStmt) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(ForStmt forStmt) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(IfStmt ifStmt) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(InstanceOf instanceOf) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(LocalVar localVar) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(LocalVarDecl localVarDecl) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(MethodCall methodCall) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(NewClass methodCall) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(NewArray newArray) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Receiver receiver) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Return aReturn) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(ReturnVoid aReturn) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(StaticClassName staticClassName) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Super aSuper) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(This aThis) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(UnaryPlus unaryPlus) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(WhileStmt whileStmt) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(DoStmt whileStmt) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(Null aNull) {
		// TODO Auto-generated method stub
		
	}
	// ???
	@Override
	public void visit(Literal literal) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(ArgumentList argumentList) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(GenericTypeVar genericTypeVar) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(GenericDeclarationList genericTypeVars) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(AssignToField assignLeftSide) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(AssignToLocal assignLeftSide) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void visit(SuperCall superCall) {
		// TODO Auto-generated method stub
		
	}

}