/** 
 * @file llimage_libtest.cpp
 * @author Merov Linden
 * @brief Integration test for the llimage library
 *
 * $LicenseInfo:firstyear=2011&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2011, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */
#include "linden_common.h"
#include "llpointer.h"

#include "llimage_libtest.h"

// Linden library includes
#include "llimage.h"
#include "llimagejpeg.h"
#include "llimagepng.h"
#include "llimagebmp.h"
#include "llimagetga.h"
#include "llimagej2c.h"
#include "lldir.h"

// system libraries
#include <iostream>

// doc string provided when invoking the program with --help 
static const char USAGE[] = "\n"
"usage:\tllimage_libtest [options]\n"
"\n"
" --help                         print this help\n"
" --in <file1> <file2>...        list of image files to load and convert\n"
" --out <file1> <file2>...       list of image files to create (assumes same order as --in files)\n"
"\n";

// Create an empty formatted image instance of the correct type from the filename
LLPointer<LLImageFormatted> create_image(const std::string &filename)
{
	std::string exten = gDirUtilp->getExtension(filename);
	U32 codec = LLImageBase::getCodecFromExtension(exten);
	
	LLPointer<LLImageFormatted> image;
	switch (codec)
	{
		case IMG_CODEC_BMP:
			image = new LLImageBMP();
			break;
		case IMG_CODEC_TGA:
			image = new LLImageTGA();
			break;
		case IMG_CODEC_JPEG:
			image = new LLImageJPEG();
			break;
		case IMG_CODEC_J2C:
			image = new LLImageJ2C();
			break;
		case IMG_CODEC_PNG:
			image = new LLImagePNG();
			break;
		default:
			return NULL;
	}
	
	return image;
}

// Load an image from file and return a raw (decompressed) instance of its data
LLPointer<LLImageRaw> load_image(const std::string &src_filename)
{
	LLPointer<LLImageFormatted> image = create_image(src_filename);

	if (!image->load(src_filename))
	{
		return NULL;
	}
	
	if(	(image->getComponents() != 3) && (image->getComponents() != 4) )
	{
		std::cout << "Image files with less than 3 or more than 4 components are not supported\n";
		return NULL;
	}
	
	LLPointer<LLImageRaw> raw_image = new LLImageRaw;
	if (!image->decode(raw_image, 0.0f))
	{
		return NULL;
	}
	
	return raw_image;
}

// Save a raw image instance into a file
bool save_image(const std::string &dest_filename, LLPointer<LLImageRaw> raw_image)
{
	LLPointer<LLImageFormatted> image = create_image(dest_filename);
	
	if (!image->encode(raw_image, 0.0f))
	{
		return false;
	}
	
	return image->save(dest_filename);
}

int main(int argc, char** argv)
{
	// List of input and output files
	std::list<std::string> input_filenames;
	std::list<std::string> output_filenames;

	// Init whatever is necessary
	ll_init_apr();
	LLImage::initClass();

	// Analyze command line arguments
	for (int arg = 1; arg < argc; ++arg)
	{
		if (!strcmp(argv[arg], "--help"))
		{
            // Send the usage to standard out
            std::cout << USAGE << std::endl;
			return 0;
		}
		else if (!strcmp(argv[arg], "--in") && arg < argc-1)
		{
			std::string file_name = argv[arg+1];
			while (file_name[0] != '-')		// if arg starts with '-', we consider it's not a file name but some other argument
			{
				input_filenames.push_back(file_name);	// Add file name to the list
				arg += 1;					// Skip that arg now we know it's a file name
				if ((arg + 1) == argc)		// Break out of the loop if we reach the end of the arg list
					break;
				file_name = argv[arg+1];	// Next argument and loop over
			}
		}		
		else if (!strcmp(argv[arg], "--out") && arg < argc-1)
		{
			std::string file_name = argv[arg+1];
			while (file_name[0] != '-')		// if arg starts with '-', we consider it's not a file name but some other argument
			{
				output_filenames.push_back(file_name);	// Add file name to the list
				arg += 1;					// Skip that arg now we know it's a file name
				if ((arg + 1) == argc)		// Break out of the loop if we reach the end of the arg list
					break;
				file_name = argv[arg+1];	// Next argument and loop over
			}
		}		
	}
		
	// Analyze the list of (input,output) files
	if (input_filenames.size() == 0)
	{
		std::cout << "No input file, nothing to do -> exit" << std::endl;
		return 0;
	}
	// TODO: For the moment, we simply convert each input file to something. This needs to evolve...
	if (input_filenames.size() != output_filenames.size())
	{
		std::cout << "Number of output and input files different -> exit" << std::endl;
		return 0;
	}

	std::list<std::string>::iterator in_file  = input_filenames.begin();
	std::list<std::string>::iterator out_file = output_filenames.begin();
	std::list<std::string>::iterator end = input_filenames.end();
	for (; in_file != end; ++in_file, ++out_file)
	{
		// Load file
		LLPointer<LLImageRaw> raw_image = load_image(*in_file);
		if (!raw_image)
		{
			std::cout << "Error: Image " << *in_file << " could not be loaded" << std::endl;
			continue;
		}
	
		// Save file
		if (!save_image(*out_file, raw_image))
		{
			std::cout << "Error: Image " << *out_file << " could not be saved" << std::endl;
			continue;
		}
		std::cout << *in_file << " -> " << *out_file << std::endl;

		// Output stats on each file
	}
	
	// Cleanup and exit
	LLImage::cleanupClass();
	
	return 0;
}