/**
 * @fileoverview PCjs-specific compile-time definitions.
 * @author <a href="mailto:Jeff@pcjs.org">Jeff Parsons</a>
 * @version 1.0
 * Created 2014-May-08
 *
 * Copyright © 2012-2014 Jeff Parsons <Jeff@pcjs.org>
 *
 * This file is part of PCjs, which is part of the JavaScript Machines Project (aka JSMachines)
 * at <http://jsmachines.net/> and <http://pcjs.org/>.
 *
 * PCjs is free software: you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation, either version 3
 * of the License, or (at your option) any later version.
 *
 * PCjs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with PCjs.  If not,
 * see <http://www.gnu.org/licenses/gpl.html>.
 *
 * You are required to include the above copyright notice in every source code file of every
 * copy or modified version of this work, and to display that copyright notice on every screen
 * that loads or runs any version of this software (see Computer.sCopyright).
 *
 * Some PCjs files also attempt to load external resource files, such as character-image files,
 * ROM files, and disk image files. Those external resource files are not considered part of the
 * PCjs program for purposes of the GNU General Public License, and the author does not claim
 * any copyright as to their contents.
 */

"use strict";

/**
 * APP_PCJS collects all PCjs application globals in one convenient place
 */
if (DEBUG) {
    var APP_PCJS = {Component: null};
    if (typeof Component === 'function') APP_PCJS.Component = Component;
}

/**
 * @define {string}
 */
var PCJSCLASS = "pcjs";         // this @define is the default application class (formerly APPCLASS) to use for PCjs

/**
 * @define {boolean}
 *
 * WARNING: DEBUGGER needs to accurately reflect whether or not the Debugger component is (or will be) loaded.
 * In the compiled case, we rely on the Closure Compiler to override DEBUGGER as appropriate.  When it's *false*,
 * nearly all of debugger.js will be conditionally removed by the compiler, reducing it to little more than a
 * "type skeleton", which also solves some type-related warnings we would otherwise have if we tried to remove
 * debugger.js from the compilation process altogether.
 *
 * However, when we're in "development mode" and running uncompiled code in debugger-less configurations,
 * I would like to skip loading debugger.js altogether.  When doing that, we must ALSO arrange for an additional file
 * (nodebugger.js) to be loaded immediately after this file, which *explicitly* overrides DEBUGGER with *false*.
 */
var DEBUGGER = true;            // this @define is overridden by the Closure Compiler to remove Debugger-related support

/**
 * @define {boolean}
 *
 * PREFETCH enables the use of a prefetch queue.
 * 
 * See the Bus component for details.
 */
var PREFETCH = false;

/**
 * @define {boolean}
 *
 * FASTDISABLE turns on memory-function switching to dynamically disable memory accesses whenever the CPU wants
 * to disable spurious memory reads (which are mostly harmless) or stale memory writes (which tend to be destructive
 * and are NOT mostly harmless).
 * 
 * If FASTDISABLE is false, then the code falls back to setting/testing internal OP_NOREAD and OP_NOWRITE opFlags
 * as needed.
 * 
 * At the moment, it seems that FASTDISABLE is a bit slower than relying on the OP_NOREAD/OP_NOWRITE flags, so it's
 * turned off; apparently, I was a bit too optimistic calling it "FAST".  But your mileage may vary, depending on the
 * browser and its version.
 *
 * See the X86CPU component for details, since it is the CPU, not the underlying Bus or Memory components, that needs
 * to be able to do this.
 */
var FASTDISABLE = false;

/**
 * @define {boolean}
 *
 * FATARRAYS is a Closure Compiler compile-time option that allocates 1 number per byte for Memory blocks;
 * wasteful, but potentially slightly faster.
 *
 * See the Memory component for details.
 */
var FATARRAYS = false;

/**
 * @define {boolean}
 * 
 * TYPEDARRAYS enables use of typed arrays for Memory blocks. This used to be a compile-time-only option, but since I've
 * added memory access functions for typed arrays (see Memory.afnTypedArray), I can turn the support on dynamically now.
 * Originally, I didn't see much of a speed increase over the original (non-typed) implementation, but that will probably
 * change over time.
 *
 * See the Memory component for details.
 * 
 * UPDATE (Oct 2014): Time has passed, and TypedArray support is still measurably slower than the default Memory implementation,
 * so it's turned off by default for now.
 */
var TYPEDARRAYS = false; // (typeof ArrayBuffer !== 'undefined');

if (typeof module !== 'undefined') {
    global.PCJSCLASS = PCJSCLASS;
    global.DEBUGGER = DEBUGGER;
    global.PREFETCH = PREFETCH;
    global.FASTDISABLE = FASTDISABLE;
    global.FATARRAYS = FATARRAYS;
    global.TYPEDARRAYS = TYPEDARRAYS;
    /*
     * TODO: When we're "required" by Node, should we return anything via module.exports?
     */
}