joomer-efsw-file-monitoring/src/joomer-efsw-file-monitoring.cpp

#define STB_IMAGE_IMPLEMENTATION
#define STB_IMAGE_WRITE_IMPLEMENTATION

#include <efsw/FileSystem.hpp>
#include <efsw/System.hpp>
#include <efsw/efsw.hpp>
#include <iostream>
#include <signal.h>
#include <cstring>
#include "stb_image.h"
#include "stb_image_write.h"

//void flip_image_horizontally(unsigned char* data, int width, int height, int channels);
void flip_image_vertically(unsigned char* data, int width, int height, int channels);

bool STOP = false;

void sigend( int ) {
	std::cout << std::endl << "Bye bye" << std::endl;
	STOP = true;
}

/// Processes a file action
class UpdateListener : public efsw::FileWatchListener {
  public:
	UpdateListener() {}

	std::string getActionName( efsw::Action action ) {
		switch ( action ) {
			case efsw::Actions::Add:
				
				return "Add";
			case efsw::Actions::Modified:
				return "Modified";
			case efsw::Actions::Delete:
				return "Delete";
			case efsw::Actions::Moved:
				return "Moved";
			default:
				return "Bad Action";
		}
	}

	void handleFileAction( efsw::WatchID watchid, const std::string& dir,
						   const std::string& filename, efsw::Action action,
						   std::string oldFilename = "" ) override {
		std::cout << "Watch ID " << watchid << " DIR ("
				  << dir + ") FILE (" +
						 ( oldFilename.empty() ? "" : "from file " + oldFilename + " to " ) +
						 filename + ") has event "
				  << getActionName( action ) << std::endl;
		
		if (action == efsw::Actions::Add || action == efsw::Actions::Modified) {
			// 1. Ignore the event if it's a file WE created
			if (filename.find("flipped_") == 0) {
				return; 
			}
			
			std::string fullPath = dir + filename;
			
			int width, height, channels;
			// Try to load
			unsigned char* image_data = stbi_load(fullPath.c_str(), &width, &height, &channels, 0);
			
			// If it fails because the file is still being written, wait and try one more time
			if (!image_data) {
				efsw::System::sleep(300);
				image_data = stbi_load(fullPath.c_str(), &width, &height, &channels, 0);
			}

			if (image_data) {
				std::cout << "Successfully loaded " << filename << " (" << width << "x" << height << ")" << std::endl;
				flip_image_vertically(image_data, width, height, channels);
				std::string flipped_filename = dir + "flipped_" + filename;
				stbi_write_jpg(flipped_filename.c_str(), width, height, channels, image_data, 100);
				stbi_image_free(image_data);
				STOP = true; 
			}
		}
	}
};

efsw::WatchID handleWatchID( efsw::WatchID watchid ) {
	switch ( watchid ) {
		case efsw::Errors::FileNotFound:
		case efsw::Errors::FileRepeated:
		case efsw::Errors::FileOutOfScope:
		case efsw::Errors::FileRemote:
		case efsw::Errors::WatcherFailed:
		case efsw::Errors::Unspecified: {
			std::cout << efsw::Errors::Log::getLastErrorLog().c_str() << std::endl;
			break;
		}
		default: {
			std::cout << "Added WatchID: " << watchid << std::endl;
		}
	}

	return watchid;
}

void flip_image_vertically(unsigned char* data, int width, int height, int channels) {
	// ... (your vertical flip implementation from before)
	int row_stride = width * channels;
	unsigned char* temp_row = new unsigned char [row_stride];
	for (int y = 0; y < height / 2; ++y) {
		unsigned char* top_row = data + y * row_stride;
		unsigned char* bottom_row = data + (height - 1 - y) * row_stride;
		std::memcpy(temp_row, top_row, row_stride);
		std::memcpy(top_row, bottom_row, row_stride);
		std::memcpy(bottom_row, temp_row, row_stride);
	}
	delete[] temp_row;
}

int main( int argc, char** argv ) {
	signal( SIGABRT, sigend );
	signal( SIGINT, sigend );
	signal( SIGTERM, sigend );

	std::cout << "Press ^C to exit demo" << std::endl;

	bool commonTest = true;
	bool useGeneric = false;
	std::string path;

	if ( argc >= 2 ) {
		path = std::string( argv[1] );

		if ( efsw::FileSystem::isDirectory( path ) ) {
			commonTest = false;
		}

		if ( argc >= 3 ) {
			if ( std::string( argv[2] ) == "true" ) {
				useGeneric = true;
			}
		}
	}

	UpdateListener* ul = new UpdateListener();

	/// create the file watcher object
	efsw::FileWatcher fileWatcher( useGeneric );

	fileWatcher.followSymlinks( false );
	fileWatcher.allowOutOfScopeLinks( false );

	if ( commonTest ) {
		std::string CurPath( efsw::System::getProcessPath() );

		std::cout << "CurPath: " << CurPath.c_str() << std::endl;

		/// starts watching
		fileWatcher.watch();

		/// add a watch to the system
		handleWatchID( fileWatcher.addWatch( CurPath + "test", ul, true ) );

		/// adds another watch after started watching...
		/*efsw::System::sleep( 100 );

		efsw::WatchID watchID =
			handleWatchID( fileWatcher.addWatch( CurPath + "test2", ul, true ) );

		/// delete the watch
		if ( watchID > 0 ) {
			efsw::System::sleep( 1000 );
			fileWatcher.removeWatch( watchID );
		}*/
	} else {
		if ( fileWatcher.addWatch( path, ul, true ) > 0 ) {
			fileWatcher.watch();

			std::cout << "Watching directory: " << path.c_str() << std::endl;

			if ( useGeneric ) {
				std::cout << "Using generic backend watcher" << std::endl;
			}
		} else {
			std::cout << "Error trying to watch directory: " << path.c_str() << std::endl;
			std::cout << efsw::Errors::Log::getLastErrorLog().c_str() << std::endl;
		}
	}

	while ( !STOP ) {
		efsw::System::sleep( 100 );
	}

	return 0;
}