/* 
 * THE GRIM MESSAGE KEEPER
 * A project for C++ newbies. 	
 * Wouldn't be possible without Arvind!
 * Send comments to: latestringtones2003@yahoo.com
 * The name's John. 
 * No responsibility whatsoever. Usual stuff.  
 * No copyright restrictions :) 
 *
 * TODO
 * - optimise range code 
 * - make non-existent functions existent.
 * - finish writing help
 */

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <string>
#include <ctime>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <dirent.h>
using namespace std;

/* version */
const char* versinfo = "0.0.7c";

void readmsg(int x);
void editmsg(char *x);
void delmsg(int x);
void get_msg_titles(void);
void do_all_messages(char *x, char *y);
void show_version(void);
void show_help(void);
void show_about(void);
void show_release_dates(void);
void show_wenda(void);
int msg_filter(const dirent *x);
void countmsgs(void);
char *get_msg_filename(int x);

int main (int argc, char **argv) {

	if (!argv[1]) /* if no argument is given - i.e. ./grim */ 
	{
		get_msg_titles();
		exit(0);
	}
	else
	{
		/* check for non-standard arguments */ 
		if (!strcmp(argv[1], "--version"))
		{
			show_version();
			exit(0);
		}
		else if (!strcmp(argv[1], "--help"))
		{
			show_help();
			exit(0);
		}

		else if (!strcmp(argv[1], "--about"))
		{
			show_about();
			exit(0);
		}

		else if (!strcmp(argv[1], "--release-dates"))
                {
                        show_release_dates();
                        exit(0);
                }

		/* this is an easter egg - it refers to Wenda from "Where's Wally" */
		else if (!strcmp(argv[1], "--wenda"))
                {
                        show_wenda();
                        exit(0);
                }
	
	}

	/* normal argument handler - thanks to Arvind */
	for (int i = 1; i < argc; i++) {    
		if (argv[i][0] == '-') {        
			switch (argv[i][1]) {      
				case 'r':
					if (argc > i + 1) {
						/* thanks to Kamran - this range handler is brilliant :) */ 
						char *read_msgs_ = "read";
						do_all_messages(argv[i + 1],read_msgs_);
						i++;
					}
					else {
						get_msg_titles();
					}
					break;

				case 'w':
					// cout << "Write message.";
					break;

				case 'd':
					if (argc > i + 1) {
						char *del_msgs_ = "delete";
                                        	do_all_messages(argv[i + 1],del_msgs_); 
						cout << "Message(s) deleted." <<  endl;
						i++;
					}
					else {
						cout << "Please enter message number to delete in argument." << endl;
						exit(0);
					}
                                        break;

				case 'c':
					countmsgs();
					exit(0);
					break;

				case 'e':
					if (argc > i + 1) {
						editmsg(argv[i + 1]);
						i++;
					}
					else {
						cout << "Please enter a message number to edit." << endl;
					}	
					break;

				default:
					cout << "Unknown argument: " << argv[i][1] << endl;
					break;
			}
		}
		else {
			cout << "Extra arg: " << argv[i] << endl;
		}
	}

	return (0);
}

/* functions */

/* read individual message - this is passed to do_all_messages() */
void readmsg(int x)
{
	string mbuffer, mbuffertmp;
	int mbuffertest, msglinelength;
	char *themsgfile;
	themsgfile = get_msg_filename(x);
	ifstream msgfile(themsgfile);
	if (! msgfile.is_open())
	{
		cout << "Error opening file.\n"; exit (1); 
	}
	cout << "\n";
	while (! msgfile.eof())
	{
		getline(msgfile,mbuffer,'\n');
		mbuffertmp = mbuffer;
		/* test for blank lines */
		mbuffertest = mbuffertmp.empty();
		if (mbuffertest == 0)
		{ 
			mbuffertmp = mbuffertmp.erase(1);
			/* the % occurs more often - used first so no need to check for T or D */
			if (mbuffertmp == "%")
			{
				msglinelength = mbuffer.length();
				if (msglinelength > 1)
				{
					mbuffer = mbuffer.substr(2);
					cout << mbuffer << endl;
				}
				else
				{
					mbuffer = mbuffer.substr(1);
					cout << mbuffer << endl;
				}
			}
			else if (mbuffertmp == "T")
			{
				mbuffer = mbuffer.substr(7);
				cout << "-----------------------------------------" << endl;
				cout << " " << mbuffer << endl;
				cout << "-----------------------------------------" << endl;
			}
			else if (mbuffertmp == "D")
			{
				mbuffer = mbuffer.substr(6);
				long tmpdate;
				tmpdate = atol(mbuffer.c_str());
				cout << "Last Modified: " << ctime(&tmpdate) << "\n";
			}
		}
	}
	cout << "\n";
}

/* ranges code thanks to Kamran - how cool is it? :D */
/* this function handles the final output (read or delete) of all selected messaages */
void do_all_messages(char *x, char *y)
{
	int range1, range2, range[10], i = 0;
	string temp, arg(x);

	/* here's the really messy part. The program first checks whether the argument contains a ','. 
	   If yes, it then checks for a '-'. If yes, it handles the argument accordingly. */

	while (arg.length() > 0)
		if (arg.find(",") < arg.length())
			if (arg.find("-") < arg.length())
			{
				int loc = arg.find_first_of(",-");
				switch (arg[loc])
				{
					case '-':
						arg.replace(loc, 1, "%");
						temp = arg.substr(0, loc);
						range1 = atoi(temp.c_str());
						int nextloc;
						nextloc = arg.find_first_of("-,");
						if (nextloc < arg.length())
						{
							temp = arg.substr(loc + 1, nextloc - loc - 1);
							arg.erase(0, nextloc + 1);
						}
						else
						{
							temp = arg.substr(loc + 3);
							arg.erase(0, loc + 1);
						}
						range2 = atoi(temp.c_str());
						while (range1 <= range2)
							range[i++] = range1++;
						break;
					case ',':
						arg.replace(loc, 1, "%");
						temp = arg.substr(0, loc);
						range[i++] = atoi(temp.c_str());
						arg.erase(0, loc + 1);
						break;
				}
			}
			else
			{
				int loc = arg.find(",");
				temp = arg.substr(0, loc);
				range[i++] = atoi(temp.c_str());
				arg.erase(0, loc + 1);
			}
		else if (arg.find("-") < arg.length())
		{
			int loc = arg.find("-");
			temp = arg.substr(0, loc);
			range1 = atoi(temp.c_str());
			temp = arg.substr(loc + 1, arg.length() - loc - 1);
			range2 = atoi(temp.c_str());
			while (range1 <= range2)
				range[i++] = range1++;
			arg.erase(0, loc + 3);
		}
		else
		{
			range[i++] = atoi(arg.c_str());
			break;
		}
	//while ends here
	--i;

	for(int j = 0; j <= i; j++)
	{
		/* read or delete messages ? */
		if (y == "read") { 
			readmsg(range[j]);
		}
		else if (y == "delete") { 
			delmsg(range[j]);
		}
		else {
		cout << "Didn't want to read or delete, you wanted to " << y << endl;
		}
	}
}

void delmsg(int x)
{
	char *fn2delete;
	fn2delete = get_msg_filename(x);		
	unlink(fn2delete);	
}

void editmsg(char *x)
{
	/* WORK IN PROGRESS */
	int etoint;
	char *emsgfilename;
	etoint = atoi(x);
	emsgfilename = get_msg_filename(etoint);
	int emsgtmpfilename;

	/* check for TMPDIR - else use /tmp */
	char *tmpdirname  = getenv("TMPDIR");
	if (tmpdirname!=NULL) 
	{ 
		/* use it */	
	//	tmpfn_temp = "/grim_message_tmp_XXXXXX";
	}
	else 
	{
		tmpdirname = "/tmp";	
	}  
	
	char *emsgtmpfilenametemplate;
// !! causes segmentation fault !!	emsgtmpfilenametemplate = strcat(tmpdirname,tmpfn_temp);
	// char tmpfntemplate_final[] = emsgtmpfilenametemplate;	
	// emsgtmpfilename = mkstemp(tmpfntemplate_final);
	// cout << tmpfntemplate_final << endl;
	// cout << emsgtmpfilename << endl;
}

/* filter() for scandir */
int msg_filter(const dirent *x)
{
	char *msgindicator = ".message";
	char *cmsgindicator;
	cmsgindicator = strstr(x->d_name,msgindicator);
	if (cmsgindicator)
	{
		return (1);
	}
	else
	{
		return (0);
	}
}

void countmsgs(void)
{
	int num_of_msgs;
	struct dirent **countedlist;
	num_of_msgs = scandir(".", &countedlist, msg_filter, versionsort);
	
	if (num_of_msgs < 0)
	{
		perror("scandir");
	}	
	else
	{	
		cout << "There are " << num_of_msgs << " messages." << endl;

		while (num_of_msgs--) {
       			free(countedlist[num_of_msgs]);
        	}
        	free(countedlist);

	}
} 

char *get_msg_filename(int x)
{
	struct dirent **msgarray;
	int msgarraynum;
	int filenum;
	msgarraynum = scandir(".", &msgarray, msg_filter, versionsort);
	char *fn; 
	filenum = msgarraynum - x;
	fn = strdup(msgarray[filenum]->d_name);
	while (msgarraynum--) {
		free(msgarray[msgarraynum]);
	}
	free(msgarray);

	return (fn);
}

void get_msg_titles(void)
{
	struct dirent **msgtitlearray;
	int msgtitlearraynum;
	msgtitlearraynum = scandir(".", &msgtitlearray, msg_filter, versionsort);
	string tmbuffer, tmbuffertmp;
	int tmbuffertest, tmsglinelength, tmsgcount=0;
	char *tthemsgfile;

	if (msgtitlearraynum < 0)
	{
		perror("scandir");
	}
	else
	{
		cout << "\n-----------------------------------------" << endl;
		cout << " Messages" << endl;
		cout << "-----------------------------------------" << endl;
		while(msgtitlearraynum--)
		{
			tthemsgfile = strdup(msgtitlearray[msgtitlearraynum]->d_name);
			ifstream tmsgfile(tthemsgfile);
			if (! tmsgfile.is_open())
			{
				cout << "Error opening file\n"; exit (1);
			}
			while (! tmsgfile.eof())
			{
				getline(tmsgfile,tmbuffer,'\n');
				tmbuffertmp = tmbuffer;
				tmbuffertest = tmbuffertmp.empty();
				if (tmbuffertest == 0)
				{
					tmbuffertmp = tmbuffertmp.erase(1);
					if (tmbuffertmp == "T")
					{
						tmsgcount++;
						tmbuffer = tmbuffer.substr(7);
						cout << tmsgcount << ". "<< tmbuffer << endl;
					}
				}
			}
			free(msgtitlearray[msgtitlearraynum]);
		}
		free(msgtitlearray); 
	}
	cout << "\n";
}

void show_version(void)
{
	cout << "Grim " << versinfo << endl;
}

void show_help(void)
{
	cout << "Usage: grim [option] [message(s)]\n";
	cout << "Manage messages.\n\n";
	cout << "OPTIONS:\n\n";
	cout << " writing messages\n";
	cout << "  -w			write new message\n";
	cout << "\n reading messages\n";
	cout << "  -r			list all message titles\n"; 
	/* have a -r all? */
	cout << "  -r x			read message x\n";
	cout << "  -r x,y		read messages x and y\n";
	cout << "  -r x-y		read all messages from x to y\n";
	cout << "\n deleting messages\n";
	cout << "  -d all		delete all messages - BE CAREFUL!\n";
	cout << "  -d x			delete message x\n";	
	cout << "  -d x,y      		delete messages x and y\n";
        cout << "  -d x-y           	delete all messages from x to y\n";

	
}

void show_wenda(void)
{
	cout << "Wenda! Boo Yeh!" << endl;
}

void show_about(void)
{
	cout << "The Grim Message Keeper is a console-based application that \n";
	cout << "stores short reminder messages. It is a project for C/C++ newbies \n";
	cout << "that is intended to offer a practical learning experience.\n";
}	

void show_release_dates(void)
{
	cout << "Release Dates:\n";
	cout << "Version 0.0.1 released: Jun 14th 2004\n";
	cout << "Version 0.0.2 released: Jun 19th 2004\n";
	cout << "Version 0.0.3 released: Jun 20th 2004\n";
	cout << "Version 0.0.4 released: Jun 32rd 2004\n";
	cout << "Version 0.0.5 released: July 5th 2004\n";
	cout << "Version 0.0.5a released: July 5th 2004\n"; 
	cout << "Version 0.0.6 released: July 5th 2004\n";
	cout << "Version 0.0.7a released: July 5th 2004\n";
	cout << "Version 0.0.7b released: July 6th 2004\n";
	cout << "Version 0.0.7c released: July 7th 2004\n";
}