#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>	/*strcpy() strcat() definition*/
#include <unistd.h>	/* getcwd() definition */
#include <getopt.h>	/*getopt() optind definition */
#include <sysexits.h>	/*exit signal definition */
#include <sys/param.h>	/*MAXPATHLEN definition */
#include <sys/stat.h>	/*stat() struct stat definition */
#include <sys/dir.h>	/*scandir() alphasort() struct dirent(and direct def) definition */

/*Will hold Filename, attributes and full path of files */
typedef struct {
	char 	fullpathname[MAXPATHLEN]; /*path + fn->dname, helps for stat() and recursive option */
	struct 	direct 	*fn; /*d_name etc */
	struct 	stat 	*fs; /*status&attributes */
}flstat;

static int	oneflag, lflag, rflag, aflag;	/*Program Options */
static int	myls(char*);			/*the LS routine */
static void	usage();			/*shows usage of Program */
static flstat	**getattr(char*,struct direct**,int); /*Reads filelist and returns a new with atributes added */
static void	print(flstat**,int);		/*Prints the contents of a flielist */

int	file_select();				/*Used by scandir() to handle files shown */

int main(int argc, char *argv[])
{
	int	c; /*temp used to get options from command line */
	char	pathname[MAXPATHLEN]; /*path to execute command */

	/*parsing command line options */
	while ((c = getopt(argc, argv, "aRrl1")) != -1)
	{
		switch (c)
		{
		case 'a': /*Show hidden option */
			aflag = 1;
			break;
		case 'R':/*Recursively option */
		case 'r':/*compatibility */
			rflag = 1;
			break;
		case 'l':/*detail option */
			lflag = 1;
		case '1':/*expand */
			oneflag = 1;
			break;
		default: /*Else show usage */
			usage();
		}
	}

	if (argv[optind] == 0) /*if not a path for ls given */
		getcwd(pathname,MAXPATHLEN); /*use Current working path */
	else
		strcpy(pathname,argv[optind]); /*use path given */

	myls(pathname); /*Execute ls */

	return EXIT_SUCCESS;
}

/*basic routine of our program */
static int myls(char *path)
{
	int	filecount,i;
	char	tmp[MAXPATHLEN];
	struct	stat 	*buf = (struct stat*)malloc(sizeof(struct stat)); /*buffer of file status */
	struct	direct	**files;	/*will get a list of files */
	flstat	**flist;		/*will keep list of files and attributes   */

	/*if path given was NULL, errormsg&exit*/
	if (path == NULL)
	{
		fprintf(stderr, "Error on getting PATH");
		exit(EXIT_FAILURE);
	}
	
	stat(path,buf); /*Get status for path */
	/*if not a directory, errormsg&exit */
	if (!S_ISDIR(buf->st_mode))
	{
		fprintf(stderr, "Fatal error - PATH given is not a directory");
		exit(EXIT_FAILURE);
	}

	filecount = scandir(path,&files,(void*)file_select,alphasort); /*scanning our path */
	flist = getattr(path,files,filecount); /*Moving the list to flist and getting file status&attributes */
	free(files); /*No longer usefull, the list is now on the flist */

	printf("%s:\ntotal %d\n",path,filecount); /*printing a header(the path) and counted files */
	print(flist,filecount);

	/*-r -R Recursively option */
	if (rflag == 1){ /*if enabled */
		for (i=0; i < filecount; i++) /*Look for direcrories in the list */
		{
			if (!(strcmp(flist[i]->fn->d_name,".") == 0 || strcmp(flist[i]->fn->d_name,"..") == 0)){ /*skip . and .. */
				if (S_ISDIR(flist[i]->fs->st_mode)) /*if got a directory */
				{
					printf("\n");
					myls(flist[i]->fullpathname); /*Execute myls for it */
				}
			}
		}
	}
	return EXIT_SUCCESS;
}

/*Returns a list with filenames, attributes and full paths */
static flstat **getattr(char *path, struct direct **list, int size)
{
	int	i;
	flstat	**thelist = (flstat**)malloc(size*sizeof(flstat*));

	for (i = 0; i < size; i++)
	{	/*Allocating memory for element */
		thelist[i] = (flstat*)malloc(sizeof(flstat));
		/*Creating a full path name of each file*/
		strcpy (thelist[i]->fullpathname,path);
		strncat(thelist[i]->fullpathname,"/",MAXPATHLEN);
		strncat(thelist[i]->fullpathname,list[i]->d_name,MAXPATHLEN);
		/*Creating new node and adding it to list */
		thelist[i]->fs = (struct stat*)malloc(sizeof(struct stat));
		stat(thelist[i]->fullpathname,thelist[i]->fs); /*get file stat */
		/*Putting the direct from scandir to our struct */
		thelist[i]->fn = list[i];
	}
	return thelist;
}

/*Prints the contents of the list provided */
static void	print(flstat **list,int size)
{
	int i;
	char sep = '\t';
	if (oneflag == 1) sep = '\n';
	for (i = 0; i < size; i++)
		printf("%s%c",list[i]->fn->d_name,sep);
	printf("\n");
	return;
}

/*Handles the files shown */
int file_select(struct direct *entry)
{
	/*if not Show All mode, return 0 for hidden files */
	if (aflag != 1)
		if (entry->d_name[0] == '.')
			return 0;
	return !0; /*else show all without check */
}

/*Prints Usage of program */
static void usage()
{
	fprintf(stderr, "%s\n%s\n",
	    "usage: lscomp [-aRr] [FILE] ...",
	    "       List information about the FILEs");
	exit(EX_USAGE);
}