/************************************************************************************

Filename    :   OVR_Log.cpp
Content     :   Logging support
Created     :   September 19, 2012
Notes       : 

Copyright   :   Copyright 2012 Oculus VR, Inc. All Rights reserved.

Use of this software is subject to the terms of the Oculus license
agreement provided at the time of installation or download, or which
otherwise accompanies this software in either electronic or hard copy form.

************************************************************************************/

#include "OVR_Log.h"
#include "OVR_Std.h"
#include <stdarg.h>
#include <stdio.h>

#if defined(OVR_OS_WIN32)
#include <windows.h>
#elif defined(OVR_OS_ANDROID)
#include <android/log.h>
#endif

namespace OVR {

// Global Log pointer.
Log* volatile OVR_GlobalLog = 0;

//-----------------------------------------------------------------------------------
// ***** Log Implementation

Log::~Log()
{
    // Clear out global log
    if (this == OVR_GlobalLog)
    {
        // TBD: perhaps we should ASSERT if this happens before system shutdown?
        OVR_GlobalLog = 0;
    }
}

void Log::LogMessageVarg(LogMessageType messageType, const char* fmt, va_list argList)
{
    if ((messageType & LoggingMask) == 0)
        return;
#ifndef OVR_BUILD_DEBUG
    if (IsDebugMessage(messageType))
        return;
#endif

    char buffer[MaxLogBufferMessageSize];
    FormatLog(buffer, MaxLogBufferMessageSize, messageType, fmt, argList);
    DefaultLogOutput(buffer, IsDebugMessage(messageType));
}

void OVR::Log::LogMessage(LogMessageType messageType, const char* pfmt, ...)
{
    va_list argList;
    va_start(argList, pfmt);
    LogMessageVarg(messageType, pfmt, argList);
    va_end(argList);
}


void Log::FormatLog(char* buffer, unsigned bufferSize, LogMessageType messageType,
                    const char* fmt, va_list argList)
{    
    bool addNewline = true;

    switch(messageType)
    {
    case Log_Error:         OVR_strcpy(buffer, bufferSize, "Error: ");     break;
    case Log_Debug:         OVR_strcpy(buffer, bufferSize, "Debug: ");     break;
    case Log_Assert:        OVR_strcpy(buffer, bufferSize, "Assert: ");    break;
    case Log_Text:       buffer[0] = 0; addNewline = false; break;
    case Log_DebugText:  buffer[0] = 0; addNewline = false; break;
    default:        
        buffer[0] = 0;
        addNewline = false;
        break;
    }

    UPInt prefixLength = OVR_strlen(buffer);
    char *buffer2      = buffer + prefixLength;
    OVR_vsprintf(buffer2, bufferSize - prefixLength, fmt, argList);

    if (addNewline)
        OVR_strcat(buffer, bufferSize, "\n");
}


void Log::DefaultLogOutput(const char* formattedText, bool debug)
{

#if defined(OVR_OS_WIN32)
    // Under Win32, output regular messages to console if it exists; debug window otherwise.
    static DWORD dummyMode;
    static bool  hasConsole = (GetStdHandle(STD_OUTPUT_HANDLE) != INVALID_HANDLE_VALUE) &&
                              (GetConsoleMode(GetStdHandle(STD_OUTPUT_HANDLE), &dummyMode));

    if (!hasConsole || debug)
    {
        ::OutputDebugStringA(formattedText);
    }
    else
    {
         fputs(formattedText, stdout);
    }    

#elif defined(OVR_OS_ANDROID)
    __android_log_write(ANDROID_LOG_INFO, "OVR", formattedText);

#else
    fputs(formattedText, stdout);

#endif

    // Just in case.
    OVR_UNUSED2(formattedText, debug);
}


//static
void Log::SetGlobalLog(Log *log)
{
    OVR_GlobalLog = log;
}
//static
Log* Log::GetGlobalLog()
{
// No global log by default?
//    if (!OVR_GlobalLog)
//        OVR_GlobalLog = GetDefaultLog();
    return OVR_GlobalLog;
}

//static
Log* Log::GetDefaultLog()
{
    // Create default log pointer statically so that it can be used
    // even during startup.
    static Log defaultLog;
    return &defaultLog;
}


//-----------------------------------------------------------------------------------
// ***** Global Logging functions

#define OVR_LOG_FUNCTION_IMPL(Name)  \
    void Log##Name(const char* fmt, ...) \
    {                                                                    \
        if (OVR_GlobalLog)                                               \
        {                                                                \
            va_list argList; va_start(argList, fmt);                     \
            OVR_GlobalLog->LogMessageVarg(Log_##Name, fmt, argList);  \
            va_end(argList);                                             \
        }                                                                \
    }

OVR_LOG_FUNCTION_IMPL(Text)
OVR_LOG_FUNCTION_IMPL(Error)

#ifdef OVR_BUILD_DEBUG
OVR_LOG_FUNCTION_IMPL(DebugText)
OVR_LOG_FUNCTION_IMPL(Debug)
OVR_LOG_FUNCTION_IMPL(Assert)
#endif

} // OVR