// Progranism Source Code: Version 2.5.1
// This new version of Progranisms should handle restrictive environments better
// It implements a better method of seeding the random number generator
// Returning to asexual behavior
// 2.5.1: Modified mutation selection code

// This is Linux code and should not compile under Windows

#include <sys/time.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>

FILE *load_file(const char *file);
void create_child(FILE *file);

int main(int argc, char *argv[])
{
	struct timeval seed;
	FILE *file = NULL;
		
	// Seed the random number generator with the number of microseconds since the Epoch
	// This ensures that even when two Progranisms execute at the "same" time they will get
	// different seeds
	gettimeofday(&seed, NULL);
	srand(seed.tv_usec);
	
	// Wait 30 seconds, +- 7
	sleep(30 + (rand() % 14) - 7);
	
	// Get a file pointer to this progranism
	file = load_file(argv[0]);
	if(file == NULL)
		return -1;
	
	// Create the children.
	int i;
	for(i = 0; i < 2; ++i)
		create_child(file);
	
	// Close files
	fclose(file);
	
	// All done
	return 0;
}

// This is a big function. It creates a new progranism from the two given files
// and then executes it.
void create_child(FILE *file)
{
	int len = 0;
	int i = 0;
	FILE *child;
	char child_name[1024];
	
	// Generate a random name for the child
	sprintf(child_name, "progranism-%i%i", rand(), rand());
	
	child = fopen(child_name, "wb");
	if(child == NULL)
		return;
	
	// Since file is used many times they can be in bad conditions (like EOF).
	clearerr(file);
	
	// Get the length of the file. This will be the file length of the child.
	fseek(file, 0, SEEK_END);
	len = ftell(file);
	
	// Reset to the beginning of the file
	fseek(file, 0, SEEK_SET);
	
	// Now write the child
	while(1)
	{
		int byte = fgetc(file);
		if(byte == EOF)
			break;
		
		// If this byte needs to be mutated than do so
		// Will cause 1 mutation every 7 children (on average).
		if((rand() % (len * 7)) == 7)
		{
			switch(rand() % 3)
			{
			case 0:	// ADD
				fputc(rand() & 0xFF, child);
				fputc(byte, child);
				break;
			case 1:	// REMOVE
				break;
			case 2: //CHANGE
				fputc(rand() & 0xFF, child);
				break;
			default:
				break;
			}
		}
		else
			fputc(byte, child);
		
		++i;
	}
	
	fclose(child);
	
	// Make executable and execute
	chmod(child_name, S_IEXEC | S_IREAD | S_IWRITE);
	char temp[1024];
	sprintf(temp, "./%s &", child_name);
	system(temp);
}

// Simply loads a file and returns its FILE *
FILE *load_file(const char *file)
{
	return fopen(file, "rb");
}