package org.simantics.scl.compiler.constants;

import java.util.Arrays;

import org.cojen.classfile.TypeDesc;
import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
import org.simantics.scl.compiler.internal.codegen.references.Val;
import org.simantics.scl.compiler.internal.codegen.types.JavaTypeTranslator;
import org.simantics.scl.compiler.internal.codegen.utils.MethodBuilder;
import org.simantics.scl.compiler.types.Type;
import org.simantics.scl.compiler.types.Types;

public class JavaConstructor extends FunctionValue {
    
    String className;
    boolean hasStaticInstance = false;
    
    TypeDesc[] parameterTypeDescs;
    
    public JavaConstructor(String className, Type effect, Type returnType, Type ... parameterTypes) {
        super(Types.freeVarsArray(Types.functionE(parameterTypes, 
                effect, returnType)), 
                effect, returnType, parameterTypes);
        this.className = className;
    }
    
    public JavaConstructor(String className, Type effect, TypeDesc[] parameterTypeDescs, 
            Type returnType, Type ... parameterTypes) {
        super(Types.freeVarsArray(Types.functionE(parameterTypes, 
                effect, returnType)),
                effect,
                returnType, parameterTypes);
        this.className = className;
        this.parameterTypeDescs = parameterTypeDescs;
    }    
    
    @Override
    public Type applyExact(MethodBuilder mb, Val[] parameters) {
        if(parameterTypeDescs == null) {
            JavaTypeTranslator tt = mb.getJavaTypeTranslator();
            parameterTypeDescs = tt.toTypeDescs(parameterTypes);
        }
        
        TypeDesc typeDesc = TypeDesc.forClass(className);
        if(hasStaticInstance) {
            mb.loadStaticField(typeDesc, "INSTANCE", typeDesc);
        }
        else {
            mb.newObject(typeDesc);
            mb.dup();
            mb.push(parameters, parameterTypes);
            mb.invokeConstructor(className, parameterTypeDescs);
            // cb.checkCast(tt.toTypeDesc(returnType));
        }
        
        return getReturnType();
    }
    
    @Override
    public String toString() {
        return className + ".<init>";
    }

    public void setHasStaticInstance(boolean hasStaticInstance) {
        if(parameterTypes.length > 0)
            throw new InternalCompilerError();
        this.hasStaticInstance = hasStaticInstance;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result
                + ((className == null) ? 0 : className.hashCode());
        result = prime * result + (hasStaticInstance ? 1231 : 1237);
        result = prime * result + Arrays.hashCode(parameterTypeDescs);
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        JavaConstructor other = (JavaConstructor) obj;
        if (className == null) {
            if (other.className != null)
                return false;
        } else if (!className.equals(other.className))
            return false;
        if (hasStaticInstance != other.hasStaticInstance)
            return false;
        if (!Arrays.equals(parameterTypeDescs, other.parameterTypeDescs))
            return false;
        return true;
    }
}