/* -*- Mode: Javascript -*-
 * -*- coding: UTF-8 -*-
 * Copyright (C) 2011 by Artur Ventura
 *
 * File: cpu.js
 * Time-stamp: Fri Jul 15 02:46:27 2011
 *
 * Author: Artur Ventura
 *
 */

#include "constantPool.jsh"
#include "opcodes.jsh"
#include "types.jsh"
#include "cpu.jsh" 

/** @constructor */
var JVM = function(params,args){
    this.nativeMappingTable = {}
    this.params = params;
    this.args = args; 
    this.method_area = {};
    this.level = 0;
    this.classpath = params.classes_to_load;
    for (var i=0; i<this.args; i++){
        if (typeof this.args[i] != "string"){
            throw "Argument " + i + " is not a string.";;
        }
    }
    this.stringHashCode = function(string){
    	var hash = 0;
    	if (string.length == 0) return hash;
    	for (i = 0; i < string.length; i++) {
    		Char = string.charCodeAt(i);
    		hash = ((hash<<5)-hash)+Char;
    		hash = hash & hash; // Convert to 32bit integer
    	}
    	return hash;
    }
    
    this.makeInstanceOfStringFromJSSTring = function(string){
        var inst = this.java_lang_string.makeInstance();
        inst["java/lang/String value"] = string;
        inst["java/lang/String hash"] = this.stringHashCode(string)
        return inst;
    }

    this.classForName = function (name){
        if (!name) { PANIC("undefined className")}
        var superClass, loaded_class = this.method_area[name];
        
        if (!loaded_class){
            loaded_class = LoadClassFile(name, this);
            this.method_area[name] = loaded_class;
            this.verifyAndLoadClass(loaded_class);
            
            LOG("[Loaded " + name  + "]");
        }
        
        return loaded_class;
        
    }
    
    this.verifyAndLoadClass = function(loaded_class){
        var superClass;
        if(loaded_class.super_class){
            // if super_class not java.lang.Object
                superClass = canonicalName(loaded_class.super_class.name_ref);
                loaded_class.super_class_ref = this.classForName(superClass);
        }

            // this doesn't seem right. doing this will cause the entire JRE to be loaded
            // as soon as you start JVM.
            
            /*
            var that = this;

            loaded_class.constantPool.each(function(constant){
                if (constant.name_ref.str.charAt(0) == "[") {
                    return;
                }
                that.verifyAndLoadClass(canonicalName(constant.name_ref));    
            }, CONSTANT_Class);*/
    };
    
    this.run = function (){
        this.java_lang_object = this.classForName("java.lang.Object");
        this.java_lang_cloneable = this.classForName("java.lang.Cloneable");
        this.java_io_serializable = this.classForName("java.io.Serializable");
        this.java_lang_string = this.classForName("java.lang.String");
        this.main_class = this.classForName(this.args[0])
        this.main_class.initializeClass();
        var method = this.main_class["method main([Ljava/lang/String;)V"];
        if (method == null){
            PANIC(this.args[0] + " doesn't have a a main method");
        }
        var array = make1DNativeArray(this.args.length,false,this.java_lang_string);
        for (var i=0; i<this.args.length; i++){
            array.value[i] = this.makeInstanceOfStringFromJSSTring(this.args[i]);                
        }
        method.invoke([array],this.main_class);
    };
};
/** @constructor */
var JVMThread = function(){
    this.pc = null;
    this.stack = [];
}
/** @constructor */
var JVMFrame = function(){
    this.local_variables = [];
    this.operand_stack = [];
    
}
/** @constructor */
function JVMPanic(message){
    this.toString = function(){
        return "JVMPanic: " + message
    }
}

function interpret(frame,code,method,xl){
    var operand_stack = frame.operand_stack;
    var local_variables = frame.local_variables;
    var opcode;
    var pc = 0;

#ifdef DEBUG_INTRP
    var temp = null; 
#endif
    
    while(pc < code.length){
        opcode = READ_NEXT();
        switch(OPCODE){
#include "intrp.def"
        default:
            PANIC("Invalid OPCODE " + opcode);
        }
#ifdef DEBUG_INTRP
        temp = null;
#endif
    }
    PANIC("PC overran CODE");
}