TinyJS_Functions.cpp

/*
 * TinyJS
 *
 * A single-file Javascript-alike engine
 *
 * - Useful language functions
 *
 * Authored By Gordon Williams <gw@pur3.co.uk>
 *
 * Copyright (C) 2009 Pur3 Ltd
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:

 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "ascript_pch.hpp"
#include "TinyJS_Functions.h"
#include "scriptMain.h"
#include "mvmFunctions.h"
#include "jsArray.h"
#include "asString.h"
#include "utils.h"

#include <math.h>
#include <cstdlib>
#include <sstream>

using namespace std;
// ----------------------------------------------- Actual Functions

ASValue scMathRand(ExecutionContext* ec)
{
    return jsDouble(double(rand()) / RAND_MAX);
}

ASValue scMathRandInt(ExecutionContext* ec)
{
    const int min = ec->getParam(0).toInt32();
    const int max = ec->getParam(1).toInt32();
    const int val = min + (int) (rand() % (1 + max - min));
    return jsInt(val);
}

ASValue scCharToInt(ExecutionContext* ec)
{
    string str = ec->getParam(0).toString(ec);
    int val = 0;
    if (str.length() > 0)
        val = (int) str.c_str()[0];
    return jsInt(val);
}

ASValue scIntegerParseInt(ExecutionContext* ec)
{
    //TODO: Make it more standard compliant (octal support, return NaN if fails...)
    //We can reuse the code which parses numeric constants.
    string str = ec->getParam(0).toString(ec);
    int val = strtol(str.c_str(), 0, 0);
    return jsInt(val);
}

ASValue scIntegerValueOf(ExecutionContext* ec)
{
    string str = ec->getParam(0).toString(ec);

    int val = 0;
    if (str.length() == 1)
        val = str[0];
    return jsInt(val);
}

ASValue scJSONStringify(ExecutionContext* ec)
{
    std::string result;
    result = ec->getParam(0).getJSON(0);
    return jsString(result);
}

ASValue scEval(ExecutionContext* ec)
{
    std::string str = ec->getParam(0).toString(ec);
    std::string dir = dirFromPath(ec->modulePath);

    return evaluate (str.c_str(), createDefaultGlobals(), dir, ec);
}

void registerDefaultClasses(Ref<JSObject> scope)
{
    scope->writeField("Object", JSObject::DefaultClass->value(), true);
    scope->writeField("String", JSString::StringClass->value(), true);
    scope->writeField("Array", JSArray::ArrayClass->value(), true);
}

// ----------------------------------------------- Register Functions
/**
 * Register default functions into the given scope.
 * @param scope
 */
void registerFunctions(Ref<JSObject> scope)
{
    registerDefaultClasses(scope);
    
    addNative("function eval(jsCode)", scEval, scope); // execute the given string (an expression) and return the result
    
    addNative("function Math.rand()", scMathRand, scope);
    addNative("function Math.randInt(min, max)", scMathRandInt, scope);
    addNative("function charToInt(ch)", scCharToInt, scope); //  convert a character to an int - get its value

    addNative("function parseInt(str)", scIntegerParseInt, scope); // string to int
    addNative("function Integer.valueOf(str)", scIntegerValueOf, scope); // value of a single character
    addNative("function JSON.stringify(obj, replacer)", scJSONStringify, scope); // convert to JSON. replacer is ignored at the moment
    //TODO: Add JSON.parse()
}