#include <stdio.h>
#include <sys/types.h>
#include <dirent.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sysexits.h>
#include <err.h>
#include "dir.h"

#define CHUNKSIZE 5
#define TOTALFILES 4000

static void
SeekDir(DIR *dirp, long loc)
{
	printf("Seeking back to location %ld\n", loc);
	xseekdir(dirp, loc);
}

static long
TellDir(DIR *dirp)
{
	long loc;

	loc = xtelldir(dirp);
	printf("telldir assigned location %ld\n", loc);
	return (loc);
}

int
main(int argc, char *argv[])
{
	DIR            *dirp;
	int		i;
	int		j;
	long		offset = 0, prev_offset = 0;
	char           *files[100];
	char		filename[100];
	int		fd;
	struct dirent  *dp = NULL;

	if (chdir("./test2") != 0) {
		err(EX_OSERR, "chdir");
	}

	/*****************************************************/
	/* Put a set of sample files in the target directory */
	/*****************************************************/

	for (i=1; i < TOTALFILES ; i++)
	{
		sprintf(filename, "file-%d", i);
		fd = open(filename, O_CREAT, 0666);
		if (fd == -1) {
			err(EX_OSERR, "open");
		}
		close(fd);
	}
	dirp = xopendir(".");
	if (dirp == NULL) {
		err(EX_OSERR, "opendir");
	}
	offset = TellDir(dirp);
	for (i = 0; i < 20; i++)
		files[i] = malloc(20);

	/*******************************************************/
	/* enumerate and delete small sets of files, one group */
	/* at a time.                                          */
	/*******************************************************/
	do {

		/*****************************************/
		/* Read in up to CHUNKSIZE file names    */
		/* i will be the number of files we hold */
		/*****************************************/
		for (i = 0; i < CHUNKSIZE; i++) {
			if ((dp = xreaddir(dirp)) != NULL) {
				strcpy(files[i], dp->d_name);

				printf("readdir (%ld) returned file %s\n",
				    offset, files[i]);

				prev_offset = offset;
				offset = TellDir(dirp);

			} else {
				printf("readdir returned null\n");
				break;
			}
		}


#ifdef SEEKFIRST
		/****************************************************************/
		/* Simuate the last entry not fitting into our (samba's) buffer */
		/* If we read someting in on the last slot, push it back        */
		/* Pretend it didn't fit. This is approximately what SAMBA does.*/
		/****************************************************************/
		if (dp != NULL) {
			/* Step back */
			SeekDir(dirp, prev_offset);
			offset = TellDir(dirp);
			i--;
			printf("file %s returned\n", files[i]);
		}

#else
		if (dp != NULL) {
			/* don't delete teh last one */
			i--;
		}
#endif
		/*****************************************/
		/* i is the number of names we have left.*/
		/*  Delete them.                         */
		/*****************************************/
		for (j = 0; j < i; j++) {
			if (*files[j] == '.') {
				printf ("skipping %s\n", files[j]);
			} else {
#if 1
				printf("Unlinking file %s\n", files[j]);
				if (unlink(files[j]) != 0) {
					err(EX_OSERR, "unlink");
				}
#endif
			}
		}
#ifndef SEEKFIRST
		/****************************************************************/
		/* Simuate the last entry not fitting into our (samba's) buffer */
		/* If we read someting in on the last slot, push it back        */
		/* Pretend it didn't fit. This is approximately what SAMBA does.*/
		/****************************************************************/
		if (dp != NULL) {
			/* Step back */
			SeekDir(dirp, prev_offset);
			offset = TellDir(dirp);
			printf("file %s returned\n", files[i]);
		}

#endif
		SeekDir(dirp, offset);
		offset = TellDir(dirp);
	} while (dp != NULL);

	xclosedir(dirp);
	//chdir("..");

}