// ***************************************************************** -*- C++ -*-

// mt-test.cpp

// Sample multi-threading program

// Discussion:          http://dev.exiv2.org/issues/1207

// Caution:             This code isn't currently exercised by any bash script in the test suite

// This code is here for use in development when multi-threading issues

// are being discussed.  For example #1207 and #1187

// It may be brought into use when Exiv2 support C++11 (#1188)

//

// WARNING:             Only builds with clang and gcc < 4.9.  I've never tried to build with Visual Studio

// requires C++11

// On Mac               #define  __cplusplus 201103L

// Older compilers      #define __cplusplus  199711

// Compiler switches:   -std=c++11 (set in samples/Makefile)

// WARNING:             auto_ptr is not supported in C++11 implemented by gcc 4.9/C++11 and later

#include <exiv2/exiv2.hpp>

#include <iostream>

#include <iomanip>

#include <cassert>

#include <string>

#include <thread>

#include <mutex>

// mutex to for exclusive reporting

std::mutex m;

void reportExifMetadataCount(int n,const char* argv[])

{

	int count = 0 ;

	std::string what;

	// count the exif metadata in the file

	try {

		Exiv2::Image::AutoPtr image = Exiv2::ImageFactory::open(argv[n]);

		assert(image.get() != 0);

		image->readMetadata();

		Exiv2::ExifData &exifData = image->exifData();

		if (!exifData.empty()) {

			Exiv2::ExifData::const_iterator end = exifData.end();

			for (Exiv2::ExifData::const_iterator i = exifData.begin(); i != end; ++i)

				count++;

		}

	} catch (Exiv2::Error& e) {

		what = e.what() ;

		count = -1;

	}

	// report to the user

	m.lock();

	std::cout << "file: "  << argv[n] << " "

	          << "n: "     << n       << " "

	          << "count: " << count   << " "

	          << (count < 0 ? "exception: " : what)

	          << what                 << std::endl;

	m.unlock();

}

int main(int argc,const char* argv[])

{

	int result = 0;

	if ( argc < 2 ) {

		std::cerr << "syntax: " << argv[0] << " [path]+" << std::endl;

		result = 1 ;

	} else {

		// Initialize XmpParser before starting threads

		Exiv2::XmpParser::initialize();

		// bucket of threads

		std::thread* threads = new std::thread[argc+1];

		// spin up the treads

		for ( int arg = 1 ; arg < argc ; arg++ ) {

			threads[arg] = std::thread(reportExifMetadataCount,arg,argv);

		}

		// wait for them to finish

		for ( int arg = 1 ; arg < argc ; arg++ ) {

			if ( threads[arg].joinable() )

				threads[arg].join();

		}

		delete [] threads;

	}

	return result;

}

// That's all Folks!

////