/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 *   Mozilla Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2009
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Vladimir Vukicevic <vladimir@pobox.com> (original author)
 *   Mark Steele <mwsteele@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include <stdarg.h>

#include "WebGLContext.h"

#include "prprf.h"

#include "nsIJSContextStack.h"
#include "jsapi.h"
#include "nsIScriptSecurityManager.h"
#include "nsServiceManagerUtils.h"
#include "nsIVariant.h"

#include "nsIDOMDocument.h"
#include "nsIDOMEvent.h"
#include "nsIDOMEventTarget.h"
#include "nsIPrivateDOMEvent.h"
#include "nsIDOMDataContainerEvent.h"

#include "nsContentUtils.h"
#include "mozilla/Preferences.h"

#if 0
#include "nsIContentURIGrouper.h"
#include "nsIContentPrefService.h"
#endif

using namespace mozilla;

void
WebGLContext::LogMessage(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);

    LogMessage(fmt, ap);

    va_end(ap);
}

void
WebGLContext::LogMessage(const char *fmt, va_list ap)
{
    if (!fmt) return;

    char buf[1024];
    PR_vsnprintf(buf, 1024, fmt, ap);

    // no need to print to stderr, as JS_ReportWarning takes care of this for us.

    nsCOMPtr<nsIJSContextStack> stack = do_GetService("@mozilla.org/js/xpc/ContextStack;1");
    JSContext* ccx = nsnull;
    if (stack && NS_SUCCEEDED(stack->Peek(&ccx)) && ccx)
        JS_ReportWarning(ccx, "WebGL: %s", buf);
}

void
WebGLContext::LogMessageIfVerbose(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);

    LogMessageIfVerbose(fmt, ap);

    va_end(ap);
}

void
WebGLContext::LogMessageIfVerbose(const char *fmt, va_list ap)
{
    static bool firstTime = true;

    if (mVerbose)
        LogMessage(fmt, ap);
    else if (firstTime)
        LogMessage("There are WebGL warnings or messages in this page, but they are hidden. To see them, "
                   "go to about:config, set the webgl.verbose preference, and reload this page.");

    firstTime = PR_FALSE;
}

CheckedUint32
WebGLContext::GetImageSize(WebGLsizei height, 
                           WebGLsizei width, 
                           PRUint32 pixelSize,
                           PRUint32 packOrUnpackAlignment)
{
    CheckedUint32 checked_plainRowSize = CheckedUint32(width) * pixelSize;

    // alignedRowSize = row size rounded up to next multiple of packAlignment
    CheckedUint32 checked_alignedRowSize = RoundedToNextMultipleOf(checked_plainRowSize, packOrUnpackAlignment);

    // if height is 0, we don't need any memory to store this; without this check, we'll get an overflow
    CheckedUint32 checked_neededByteLength
        = height <= 0 ? 0 : (height-1) * checked_alignedRowSize + checked_plainRowSize;

    return checked_neededByteLength;
}

nsresult
WebGLContext::SynthesizeGLError(WebGLenum err)
{
    // If there is already a pending error, don't overwrite it;
    // but if there isn't, then we need to check for a gl error
    // that may have occurred before this one and use that code
    // instead.
    
    MakeContextCurrent();

    UpdateWebGLErrorAndClearGLError();

    if (!mWebGLError)
        mWebGLError = err;

    return NS_OK;
}

nsresult
WebGLContext::SynthesizeGLError(WebGLenum err, const char *fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    LogMessageIfVerbose(fmt, va);
    va_end(va);

    return SynthesizeGLError(err);
}

nsresult
WebGLContext::ErrorInvalidEnum(const char *fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    LogMessageIfVerbose(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_ENUM);
}

nsresult
WebGLContext::ErrorInvalidOperation(const char *fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    LogMessageIfVerbose(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_OPERATION);
}

nsresult
WebGLContext::ErrorInvalidValue(const char *fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    LogMessageIfVerbose(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_VALUE);
}

nsresult
WebGLContext::ErrorOutOfMemory(const char *fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    LogMessageIfVerbose(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_OUT_OF_MEMORY);
}

const char *
WebGLContext::ErrorName(GLenum error)
{
    switch(error) {
        case LOCAL_GL_INVALID_ENUM:
            return "INVALID_ENUM";
        case LOCAL_GL_INVALID_OPERATION:
            return "INVALID_OPERATION";
        case LOCAL_GL_INVALID_VALUE:
            return "INVALID_VALUE";
        case LOCAL_GL_OUT_OF_MEMORY:
            return "OUT_OF_MEMORY";
        case LOCAL_GL_INVALID_FRAMEBUFFER_OPERATION:
            return "INVALID_FRAMEBUFFER_OPERATION";
        case LOCAL_GL_NO_ERROR:
            return "NO_ERROR";
        default:
            NS_ABORT();
            return "[unknown WebGL error!]";
    }
};
