#! /usr/bin/perl -w

#Tue Aug  9 18:31:56 2005
#Sweet little appointment planer written by Robin Wenglewski <robin@wenglewski.de>
#please keep me up to date with changes on this programm. I know it's not perfect (nor is it my english) but 
#I would be glad to hear suggestions for improvement

use Date::Calc qw(Mktime);
use Date::Calc qw(Today_and_Now);
use Getopt::Std;
use Time::localtime;
use Term::ReadKey;

#getting the options
my $optstring = 'nls:ad';
getopts("$optstring", \%opt ) or die "error with getopts";

#optional
if ($opt{a}) {$all='true';} else {$all='false';}

#what happens with which option
if ($opt{n}) {&new;}
elsif ($opt{l}) {&list;}
elsif ($opt{s}) {&search;}
elsif ($opt{d}) {&demon;}
else {&usage};


sub demon() {
    open(IFILE,"<\.termine");
    while(<IFILE>) {
        #splitting the lines line up
        my @parts=split("\:\:",$_);
        #filtering invalid an past appoitments
        if ($#parts!=2 || ($all eq 'false' && $parts[0]<(time))) {next;}
        #with the next appoitment, start &countdown
        if ($parts[0]>(time)) {&countdown(@parts); }}
    close IFILE;}


sub printday() {
    open(IFILEDAY,"<\.termine");
    print "\n\nDay appointments:\n";
    #getting the momentanious time
    my ($y,$m,$d,$h,$min,$s) = Today_and_Now([$gmt]);
    #etime is the time of the last second of that day
    my $etime = Mktime($y,$m,$d,23,59,59);
    while(<IFILEDAY>) {
        my $line = $_;
        my @parts=split("\:\:",$line);
        #filter invalids
        if ($#parts!=2 || ($all eq 'false' && ($parts[0]<=$_[0] || $parts[0]>=$etime))) {next;}
        #print the rest
        if ($parts[0]>(time)) {&printtermin($line); }}}
    close IFILEDAY;

sub countdown() {
    #getting the argument
    my $line=$_;
    my @parts=split("\:\:",$line);
    #variable for a pressed key
    my $key="";
    #creating new process and saving the id in $pid
    my $pid = fork();
    
    # The Child-Prozess
    if($pid == 0){
    open(IFILE,"<\.termine"); 
           while(1){
               #clearing sceen
                 system("clear");
                 print(ctime(time)."\n");
                 #getting the remaining time
                 my $s = $parts[0]-(time);
                 my $d=0;
                 my $h=0;
                 my $m=0;
                 if ($s>=60) {
                    
 $tmp=$s % 60; 
                    
 $m=($s-$tmp) / 60; 
                    
 $s=$tmp;
                 if ($m>=60) {
                    
 $tmp=$m % 60; 
                    
 $h=($m-$tmp) / 60; 
                    
 $m=$tmp;
                 if ($h>=24) {
                    
 $tmp=$h % 24; 
                    
 $d=($h-$tmp) / 24; 
                    
 $h=$tmp;
                    
 }}}
            #printing the remaining time
                 print ("\nnext appointment in $d Tagen $h\:$m\:$s\n");
                 #printing the coming appointment
                 print ("\ncoming appointment:\n\n");
                 &printtermin($line);
                 #print the rest of the appointments of that day
                 &printday($parts[0]); 
                 #making sure that the whileloop doesn't take all resources
                 system("sleep 1");}
    #Main Process
    } else {
    #when a key is pressed, you don't have to press also <return>
    ReadMode "raw";    
    #as long as q isn't pressed
    while(!($key eq "q")) {
        open(TTY, "</dev/tty");
        #waiting for a key stroke
        $key = ReadKey 0, *TTY; }
    #when q was pressed, Readmode back to normal
    ReadMode "normal";
    print "\n";
    close IFILE; 
    #and killing the child process
    kill 9,$pid;
    #and exit the programm
    exit;}}
    

sub search() {
    open (IFILE,"<\.termine");
    while(<IFILE>) {
    #if the line contains the demanded string, print it
        if($_ =~ /$opt{s}/i) {&printtermin($_);}}
    close IFILE; }

sub list() {
    open (IFILE,"< \.termine");
    while(<IFILE>) {
        &printtermin($_);}
    close IFILE;
    }
    
sub printtermin() {
    #split up the given argument (it has to be a line)
    @parts=split("\:\:",$_[0]);
    #filter invalids
    if ($#parts!=2 || ($all eq 'false' && $parts[0]<(time))) {return 1;}
    #and print the appointment
    print ctime($parts[0]).': '.$parts[1]."\n".$parts[2]; }
    

sub new() {
    #get title and time
    my $titel=$ARGV[2];
    my $seks=&zeitumrechnung($ARGV[0],$ARGV[1]);
    print "Please enter now further informations:\n";
    $info=<STDIN>;
    open(OFILE, ">> \.termine");
    #print everything in file
    print OFILE "$seks\:\:$titel\:\:$info";
    close OFILE;
    #arrange it
    &arrange;
    }


sub arrange() {
    my @termine;
    #open one input and one output file
    open(IFILE,"< \.termine");
    open(OFILE,"> \.termine.new");
    while(<IFILE>) {
        #split each line
        @parts=split("\:\:",$_);
        #and push it in termine (@parts should contain three variables)
        push(@termine,@parts); }
    close IFILE;
    #now the real arrangement follows
    for($i=0;$i<=$#termine-5;$i+=3) {
        for ($j=$i+3;$j<=$#termine-2;$j+=3) {
            if($termine[$i]>$termine[$j]) {
               
 ($termine[$i], $termine[$j]) = ($termine[$j], $termine[$i]);
               
 ($termine[$i+1], $termine[$j+1]) = ($termine[$j+1], $termine[$i+1]);
               
 ($termine[$i+2], $termine[$j+2]) = ($termine[$j+2], $termine[$i+2]); } }}
    for($i=0;$i<=$#termine-2;$i+=3) {
        #and here the termine array is printed back to a file
        print OFILE "$termine[$i]\:\:$termine[$i+1]\:\:$termine[$i+2]"; }
    close OFILE;
    #now the new file substitutes the old one
    system("mv -f .termine.new .termine");
    }


sub zeitumrechnung() {
    my $datum=$_[0];
    my @datum=split('\.',$datum);
    my $zeit=$_[1];
    my @zeit=split(':',$zeit);
    #make a $time format and return it
    my $time = Mktime($datum[2],$datum[1],$datum[0],$zeit[0],$zeit[1],0);
    return $time; }
    
sub usage() {
    print "\nusage: apps.pl [command]
        -l lists all coming appointments
        -n [dd.mm.yyyy hh:mm NAME] creates an appointment to the given time under the name NAME
        -s [PATTERN] looks through the coming appointments for the pattern
        -d deamon (q=quit)
        
        OPTIONAL
        -a lists all\n\n"; }