#!/usr/bin/perl
# Changelog:
# ver. 0.10 Sun June 20 2004
# Fix recurring meetings
# ver. 0.9 Sun Apr 20 2003
# MST Translate from hebrew mail that comes in 8-bit encoding.
#     On failure, exit and dont create an appointment (only note)
#     Heuristic to allow white space at the beginning of When: lines 
# ver. 0.8 Thu Oct 25
# MST Handle events that span several days
# ver. 0.7 Thu Sep 13
# MST Handle european format dates like 31/05/2001 when
#    the first number is > 12
# ver. 0.6 Wed Jun 20
# MST fixed bug in multiline When:, added hebrew date parsing
# ver. 0.5 Wed Aug 30
# MST fix bug in date parsing
# ver. 0.4 Thu May 18
# MST switch to using Date::Manip perl library for date
# parsing and calculations.
# Time zone support
# By default, create a TODO item if date can not be parsed.
# ver. 0.3 Wed May  3
# MST add space after "Location" field to show better in ical,
#     option to limit the message length
# ver. 0.2 Thu Mar 16
# MST - better handle multi-line dates and recurring events
# ver. 0.1 Sun Mar 12 
# Marc Martinez - fixes for perl 5.005


#Set this variable to limit the message length to first $top_lines.
#This is useful to make sure that you don't get a reminder
#notice that fill your entire screen.
$top_lines=20;

#Set this variable to enable zone conversion
$use_zone=1;

use Date::Manip;

#This might be needed to fix your local time zone
#if Date::Manip is installed incorrectly or
#if you have a non-standard time zone
#
&Date_Init("TZ=+0200");

#This is a pattern to match your local time zone: zone 
# conversions will be ignored for this zone
$local_zone="Israel";

#Uncomment this if you prefer the script to exit
#if there is an error parsing the message
#By default, creates a TODO item for today with
#a message
#$on_errorOnError=1;

$allmonths="1 2 3 4 5 6 7 8 9 10 11 12";
#Date format for ical
$date_format="%d/%m/%Y";
#$date_format="%e/%f/%Y";
$arg=shift @ARGV;
$task=1 if ($arg eq "-task");



chop($hostname = `hostname`);

while(<STDIN>) {
    chomp;
    s/^>\s*//o;
    if ($previous =~ m/^\s*------_=_NextPart/o &&
	m#^\s*Content-Type:#o && ! m#text/plain#o) {
	$skip_attachment=1;
    }
    if (m/^\s*------_=_NextPart/) {
	$skip_attachment=0;
	$previous=$_;
	next;
    }
    if ($skip_attachment) {
	$previous=$_;
	next;
    }

    s/\[/(/go;
    s/\]/)/go;
    if (/^-----Original Appointment-----/) {
	$from=undef;
	$subj=undef;
	$when=undef;
	$where=undef;
	@text=undef;
	$is_text=undef;
	$is_sep=undef;
	$forward=1;
	next;
    }
    #s/^>\s*//o if ($forward);
    if ($task) {
	last if ($previous =~m/^-----/o) and (/^Message-ID:/o);
	last if ($is_sep and /^------_=_NextPart/o);
    }
    if ($is_sep and $is_text) {
	push @text,$_;
	next;
    }
    $from=$1 if (/^From:\s*(.*)/);
    $subj=$1 if (/^Subject:\s*(.*)/);
    $when=$_ if (/^When:/);
    if (/^\s*When:/ and not defined ($when)) {
      $when=$_; $when=~s/^\s*//;
    } 
    if ((not /^[A-Za-z]+:/) and ($previous =~ m/^When:/)
         and not (/^\*~\*~\*~\*~\*~\*~\*~\*~\*~\*/) ) {
	$when.=" " . $_;
	$previous .=" " . $_;
	next;
    }
    $due=$1 if (/^Due Date:\s*(.*)/);

    $where=$1 if (/^Where:\s*(.*)/);
    $where =~ s/\s*$//;
    
    if ($task) {
	if (/^Owner:/) {
	    $is_sep=1;
	    $is_text=0;
	} else {
	    $is_text=1;
	}
    }
    else {
	if ($forward) {
	    if (/^$/) {
		$is_sep=1;
	    } else {
		$is_text=1;
	    }
	} else {
	    if (/^\*~\*~\*~\*~\*~\*~\*~\*~\*~\*/) {
		$is_sep=1;
		$is_text=0;
	    } else {
		$is_text=1;
	    }
	}
    }

    $previous=$_;
}
$owner=$from;
$content=$subj;
$content.="\nLocation: $where " if ($where);
$content.="\n". join("\n",@text);

if (defined ($top_lines)) {
#Ignore all but the first $top_lines lines
    @content_array=split("\n",$content);
    if ($#content_array > $top_lines) {
	$content = join("\n",@content_array[1..$top_lines],"...");
    }
}

##################################################################
# Translate Hebrew to English
##################################################################
$due = heb2eng($due);
$when = heb2eng($when);

##################################################################
# Formatted Output for ical
##################################################################

$date=$when;
if ($task) {
    $sdate=&UnixDate($due,$date_format);
    create_todo($sdate);
    exit(0);
} 
elsif ($date=~m#^When:\s+Occurs\s+every\s+(.*)\s+effective\s+(.*)#) {
    ($sdate,$start,$length,$fdate,$offset)=gettimes($2);


    ($every,$weekdays)=getevery($1,$offset);
    $every || $weekdays || on_error ("1: Unable to parse date : $1");

    create_item($sdate,$start,$length,$fdate,$every,$weekdays);
    exit(0);

} 
elsif ($date=~m#^When:\s+Occurs\s+day\s+(.*)of every\s+([0-9]+)\s+month\(s\)\s+effective\s+(.*)#) {
    ($sdate,$start,$length,$fdate,$offset)=gettimes($3);


#    ($every,$weekdays)=getevery($1,$offset);
#    $every || $weekdays || on_error ("1: Unable to parse date : $1");

    create_item($sdate,$start,$length,$fdate,undef,undef,$2);
    exit(0);

} 
elsif ($date=~m/^When:(.*)/) {
    ($sdate,$start,$length)=gettimes($1);
    create_item($sdate,$start,$length);
    exit(0);
} 
else {
    on_error ( "2: Unable to parse date: $date\n");
}

#Get number of week day (given by name)+ offset days.
sub getdaynum {
    my($name,$offset)= @_;
    my($d);
    getday: {
	    $d=1, last getday if ($name =~ m/^Sun/oi); 
	    $d=2, last getday if ($name =~ m/^Mon/oi); 
	    $d=3, last getday if ($name =~ m/^Tue/oi); 
	    $d=4, last getday if ($name =~ m/^Wed/oi); 
	    $d=5, last getday if ($name =~ m/^Thu/oi); 
	    $d=6, last getday if ($name =~ m/^Fri/oi); 
	    $d=7, last getday if ($name =~ m/^Sat/oi); 
	    return undef;
	}

    $d = $d +$offset;
    if ($d < 1) { $d=$d+7;}
    if ($d > 7) { $d=$d-7;}

    return $d;
}

#return start date, start time and length , finish date
#(if available) and offset (in days).
#The offset is non zero if the same time falls
#on different days in the two time zones,
#and equals [day_here] - [day_there]


#Handles the following patterns:
#1/27/00 from 2:00 PM to 3:00 PM (GMT+02:00) Israel.
#1/27/00 until 1/27/00 from 2:00 PM to 3:00 PM (GMT+02:00) Israel.
#12/20/1999 from 11:00 AM to 12:00 PM (GMT+02:00) Israel.
#Thursday, January 20, 2000 3:00 PM-4:00 PM (GMT+02:00) Israel.
#Wednesday, August 30, 2000 14:00-15:00 (GMT+02:00) Israel.
#When: יום חמישי 01 נובמבר 2001 15:30 to יום שישי 02 נובמבר 2001 0:00

sub gettimes {
    my($in)=@_;
    my($date)=$in;
    if ($date =~ s/\s+from\s+([0-9]+:[0-9]+.*)//) {
    } elsif ($date =~ s/([0-9]+:[0-9]+.*)//) {
    } else {
	on_error ("3: Unable to parse date $in");
    }
    my($times)=$1;
    $times=~s/\(GMT([^)]*)\)\s*(.*)//;
    my($zone_hours)=$1;
    my($zone_name)=$2;

    #ignore zone if this is local one
    $zone_hours = undef if ($local_zone && $zone_name =~ m/$local_zone/);
    #Remove : from zone, to get +-HHMM format
    $zone_hours =~ s/:\s//g;

    my($tfrom,$tto)=split(/\bto\b|-/,$times);
    my($dstop);
    
    if (not ($tto =~ m/^\s*[0-9]+:[0-9]+.*/)) {
       $tto =~ s/^(.*\s+)([0-9]+:[0-9]+.*)/$2/;
       $dstop = $1;
    }

    on_error ("4: Unable to parse date: $in") if not ($tfrom and $tto);

    my($dstart,$dfinish) = split(/until/,$date);

    #Form times for ParseDate
    if (not $dstop) { $dstop=$dstart; }
    my($from)="$dstart $tfrom $zone_hours";
    my($to)="$dstop $tto $zone_hours";

    my($date0,$date1,$date2,$length, $stime, $sdate, $fdate);
    $date1=&ParseDate($from) || on_error ("5: Unable to parse date: $from");
    $date2=&ParseDate($to) || on_error ("6: Unable to parse date: $to");
    $date0=&Date_SetTime($date1,"00:00");
    $stime=&Delta_Format(&DateCalc($date0,$date1),0,"%mh");
    $length=&Delta_Format(&DateCalc($date1,$date2),0,"%mh");
    $sdate=&UnixDate($date1,$date_format);
    if ($dfinish) {
	my($date3)=&ParseDate($dfinish) || on_error ("7: Unable to parse date: $dfinish");
	$fdate=&UnixDate($date3,$date_format) || 
	on_error ("8: Unable to parse date: $dfinish");
    }

    #Offset: check if the time falls on different days
    #in the local and specified time zone. If it does, offset is the
    #difference [day_here] - [day_there]
    my($offset);
    if ($use_zone) {
        #Calculate offset. We need to find out what day is it "there",
        #that is just strip the zone
	my($from_here)="$dstart 00:00";
	my($date0_here)=&ParseDate($from_here) || 
	    on_error ("9: Unable to parse date: $from_here");
	$offset=&Delta_Format(&DateCalc($date0_here,$date0),0,"%dh");
    }

    return ($sdate,$stime,$length, $fdate,$offset);
}


#Return weekdays and/or 
#Recurring patterns:
#every 2 week(s) on Thursday 
#every 2 days(s) 
#every Monday and Wednesday
#every Monday
#input : recurrence pattern + 
#day offset.
# The offset is for weekly patterns with
# time zones: we might need to fix the 
# week day.
sub getevery {
    my($in, $offset)=@_;
    my($every,@weekdays,$d,$day);
    if ($in =~ m/^\s*([0-9]+)\s+week/) {
	$every=$1*7;
	return ($every,undef);
    }
    if ($in =~ m/^\s*([0-9]+)\s+day/) {
	$every=$1;
	return ($every,undef);
    }
#Try to match weekdays
    my(@list)=split(/((and)?[\s,])+/,$in);

    foreach $d (@list) {
        $day=getdaynum($d, $offset);
        next if not defined($day);
	push @weekdays,$day;
    }
#If there is only one week day, just translate it to
#every 7th day
    return (7,undef) if ($#weekdays < 1);
    return (undef,join(' ',@weekdays));
}

sub create_todo {
    my($sdate)=@_;
    if (not $sdate) {
	$sdate=&UnixDate("today",$date_format);
    }
    print "Note [\n";
    print "Length [30]\n";
    print "Uid [$hostname" . "_" . "$$]\n";
    print "Owner [$owner]\n";
    print "Contents [$content]\n";
    print "Remind [0]\n";
    print "Hilite [always]\n";
    print "Todo []\n";
    print "Dates [Single $sdate End\n";
    print "]\n";
    print "]\n";
}

sub create_item {
    my($sdate,$start,$length,$fdate,$every,$weekdays,$monthly)=@_;
    print "Appt [\n";
    print "Start [$start]\n";
    print "Length [$length]\n";
    print "Uid [$hostname" . "_" . "$$]\n";
    print "Owner [$owner]\n";
    print "Contents [$content]\n";
    print "Remind [1]\n";
    print "Hilite [always]\n";

    if ($every || $weekdays || $monthly) {
	if ($monthly) {
	    print "Dates [Months $sdate $monthly\n";
  } elsif ($every) {
	    print "Dates [Days $sdate $every\n";
	} elsif ($weekdays) {
	    print "Dates [WeekDays $weekdays Months  $allmonths\n";
	} 
	if ($fdate) {
	    print "Start $sdate\n";
	    print "Finish $fdate End\n";
	} else {
	    print "Start $sdate End\n";
	} 
    } else {
	print "Dates [Single $sdate End\n";
    }

    print "]\n";
    print "]\n";
}

sub on_error {
    if ($dieOnError) {
	print STDERR join("\n",@_); 
	exit(1);
    }
    $content=join("\n",@_,$content);
    create_todo;
    exit(2);
}

#Translate hebrew mime into plain english
sub heb2eng {
  my($line)=@_;

  #Guess this is Hebrew by the fact that date zone is Jerusalem
  return $line unless ( $line =~ m/Jerusalem/);

  #Remove extra = that may appear in the encoding
  $line =~ s/\s+=\s+/ /go;
  #Yom rishon/sheni/shlishi/revii/hamishi/shishi/shabat
  $line =~ s/=E9=E5=ED\s+(=F8=E0=F9=E5=EF|=E0(=[0-9A-F][0-9A-F])*)/Sunday/go;
  $line =~ s/=E9=E5=ED\s+(=F9=F0=E9|=E1(=[0-9A-F][0-9A-F])*)/Monday/go;
  $line =~ s/=E9=E5=ED\s+(=F9=EC=E9=F9=E9|=E2(=[0-9A-F][0-9A-F])*)/Tuesday/go;
  $line =~ s/=E9=E5=ED\s+(=F8=E1(=E9)?=F2=E9|=E3(=[0-9A-F][0-9A-F])*)/Wednesday/go;
  $line =~ s/=E9=E5=ED\s+(=E7=EE=E9=F9=E9|=E4(=[0-9A-F][0-9A-F])*)/Thursday/go;
  $line =~ s/=E9=E5=ED\s+(=F9=E9=F9=E9|=E5(=[0-9A-F][0-9A-F])*)/Friday/go;
  $line =~ s/=E9=E5=ED\s+(=F9=E1=FA|=E6(=[0-9A-F][0-9A-F])*)/Saturday/go;

  $line =~ s/\xE9\xE5\xED\s+(\xF8\xE0\xF9\xE5\xEF|\xE0[\xE0-\xFA]*)/Sunday/go;
  $line =~ s/\xE9\xE5\xED\s+(\xF9\xF0\xE9|\xE1[\xE0-\xFA]*)/Monday/go;
  $line =~ s/\xE9\xE5\xED\s+(\xF9\xEC\xE9\xF9\xE9|\xE2[\xE0-\xFA]*)/Tuesday/go;
  $line =~ s/\xE9\xE5\xED\s+(\xF8\xE1(\xE9)?\xF2\xE9|\xE3[\xE0-\xFA]*)/Wednesday/go;
  $line =~ s/\xE9\xE5\xED\s+(\xE7\xEE\xE9\xF9\xE9|\xE4[\xE0-\xFA]*)/Thursday/go;
  $line =~ s/\xE9\xE5\xED\s+(\xF9\xE9\xF9\xE9|\xE5[\xE0-\xFA]*)/Friday/go;
  $line =~ s/\xE9\xE5\xED\s+(\xF9\xE1\xFA|\xE6[\xE0-\xFA]*)/Saturday/go;

  #Months
  $line =~ s/=E9(=E0)?=F0=E5=E0=F8/January/go;
  $line =~ s/=E9(=E0)?=F0=E5=E0=F8/January/go;
  $line =~ s/=F4=E1=F8=E5=E0=F8/February/go;
  $line =~ s/=EE=F8=F5/March/go;
  $line =~ s/=E0=F4=F8=E9=EC/April/go;
  $line =~ s/=EE=E0=E9/May/go;
  $line =~ s/=E9=E5=F0=E9/June/go;
  $line =~ s/=E9=E5=EC=E9/July/go;
  $line =~ s/=E0=E5=E2=E5=F1=E8/August/go;
  $line =~ s/=F1=F4=E8=EE=E1=F8/September/go;
  $line =~ s/=E0=E5=F7=E8=E5=E1=F8/October/go;
  $line =~ s/=F0=E5=E1=EE=E1=F8/November/go;
  $line =~ s/=E3=F6=EE=E1=F8/December/go;

  $line =~ s/\xE9(\xE0)?\xF0\xE5\xE0\xF8/January/go;
  $line =~ s/\xE9(\xE0)?\xF0\xE5\xE0\xF8/January/go;
  $line =~ s/\xF4\xE1\xF8\xE5\xE0\xF8/February/go;
  $line =~ s/\xEE\xF8\xF5/March/go;
  $line =~ s/\xE0\xF4\xF8\xE9\xEC/April/go;
  $line =~ s/\xEE\xE0\xE9/May/go;
  $line =~ s/\xE9\xE5\xF0\xE9/June/go;
  $line =~ s/\xE9\xE5\xEC\xE9/July/go;
  $line =~ s/\xE0\xE5\xE2\xE5\xF1\xE8/August/go;
  $line =~ s/\xF1\xF4\xE8\xEE\xE1\xF8/September/go;
  $line =~ s/\xE0\xE5\xF7\xE8\xE5\xE1\xF8/October/go;
  $line =~ s/\xF0\xE5\xE1\xEE\xE1\xF8/November/go;
  $line =~ s/\xE3\xF6\xEE\xE1\xF8/December/go;
  
  #Hebrew dates are sometimes in reverse order
  #If it is possible to figure out from the format 
  # (because first number is >12), do so for all dates

  #Note if there is one match, we change all dates,
  #as they are always in consistent format
  
  if ($line =~ m#\s(1[3-9]|2[0-9]|3[0-1])/(0?[1-9]|1[0-2])/#) {
    $line =~ s#(\s)(0?[1-9]|[1-2][0-9]|3[0-1])/(0?[1-9]|1[0-2])/#$1$3/$2/#g;
  }

  return $line;
}