#!/bin/bash
# Sun Jan 18 16:48:55 EST 2004
# NAME: pop3ck
# Copyright 2004, Chris F.A. Johnson
# Released under the terms of the GNU General Public License

version() {
    echo "    $progname, version $version
    Copyright $copyright, $author $email
    This is free software, released under the terms of the GNU General
    Public License.  There is NO warranty; not even for MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE.
"
}

usage() {
echo "    $progname -

    USAGE: $progname [OPTIONS]

    OPTIONS:

        -c FILE   - use FILE for server information
                    (will prompt for details if file does not exist)

        -s        - Print number of messages and exit

        -h        - help: print this message
        -H        - help: print more detailed message
        -v        - verbose:
        -V        - print version information

    Copyright 2004, Chris F.A. Johnson
"
}

set_chars() { #== create string of all 255 chars
    q='0 1 2 3 4 5 6 7 8 9 a b c d e f'
    chars=`for a in $q
           do
             for b in $q
             do
               case $a$b in
                 00) ;;
                 7f) printf "\x11" ;;
                 *) printf "\x$a$b" ;;
               esac
             done
           done`
}

get_key() { #== store keypress from list of permissible characters
    local OKchars=${1:-"$allkeys"}
    local k
    local error=0
    local gk_tmo=${getkey_time:-${DFLT_TIME_OUT:-600}}
    local ESC_END=[a-zA-NP-Z~^$]
    type read_mouse >/dev/null 2>&1 || read_mouse() { :; }
    mouse_x=0 mouse_y=0 mouse_b=0 mouse_line=0
    printf "$mouse_on"
    stty -echo
    while :; do
      IFS= read -r -d '' -sn1 -t$gk_tmo _GET_KEY </dev/tty 2>&1 || break
      index "$OKchars" "$_GET_KEY"
      if [ "$_INDEX" -gt 0 ]
      then
	case $_GET_KEY in
	    ${ESC})
		while :; do
		  IFS= read -rst1 -d '' -n1 k </dev/tty || break 2
		  _GET_KEY=$_GET_KEY$k
 		  case $k in
		      $ESC_END)
			  [ "$_GET_KEY" = "$MSI" ] && read_mouse
			  break 2
			  ;;
		  esac
		done
		;;
	     *) break;;
	esac
      fi
    done
    printf "$mouse_off"
    return $error
}

index() { #== index return position of STR2 in STR1
    local idx
    case $1 in
        *$2*)
            idx=${1%%"${2}"*};
            _INDEX=$(( ${#idx} + 1 ))
	    ;;
        *)
            _INDEX=0
	    ;;
    esac
}

cls() {
    printf "${CLS:=`clear`}"
}

printat() { #== print arguments 3-... at Y=$1 X=$2
    [ $# -lt 2 ] && return 1
    local y=$1
    local x=$2
    shift 2
    local msg="$*"
    printf "${CSI}%d;%dH%b" ${y//[!0-9]} ${x//[!0-9]} "$msg"
}

getline() {
    [ $1 = -s ] && { shift; local opt=-s; } || local opt=
    local var=$1
    shift
    eval read $opt -ep \" "$*": \" $var
}

create_config() {
    stty=`stty -g`
    stty echo icanon
    printf "${CVIS}\n\n"
    while :
    do
      [ -n "$pop" ] || getline pop " Enter pop3 mail server"
      [ -n "$user" ]   || getline user   "        Enter user name"
      [ -n "$pass" ]   || getline pass   "         Enter password"
      printf "\n\t1.      Server: %s\n" $pop
      printf "\t2.        User: %s\n" $user
      printf "\t3.    Password: %s\n" $pass
      printf "\t4. Config file: %s\n\n" $config_file

      read -sn1 -p " To make a change, enter the number, otherwise press <ENTER>: " l
      echo
      case $l in
	  1) getline pop " Enter pop3 mail server" ;;
	  2) getline user "        Enter user name" ;;
	  3) getline pass "         Enter password" ;;
	  4) getline config_file "      Enter config file" ;;
	  *) break ;;
      esac
    done
    echo
    {	echo "pop=$pop"
	echo "user=$user"
	echo "pass=$pass"
    } > "${config_file:-$HOME/.pop3ckrc}"
    stty $stty
    printf "${CINV}\n"
}

connect() { ## open connection to POP server and log in
    exec 3<> /dev/tcp/$pop/${port:=110}
    read -rt${timeout:-2} ok num x <&3 || return 5
    _CONNECT=1
    popcmd user $user
    popcmd pass $pass  || return 5
}

popcmd() {
    cmd=$*
    echo $cmd >&3
    read -rt${timeout:-2} ok num x <&3 || return 5
    [ "$ok" = "+OK" ]
}

set_pl() {
    local num=${1:-0}
    [ $num -eq 1 ] && pl= || pl=s
}

pop3stat() {
    [ -f "$config_file" ] && . "$config_file" || return 5
    connect
    popcmd stat || return 3
    set_pl $num
    num_messages=$num
    _POP3STAT="$num message$pl"
}

popread() {
    local header=1
        while IFS= read -r line
        do
          line=${line%$CR}
          case $line in
              "") header=0; printf "\n\n" ;;
              .) break ;;
              *)
                  if [ $header -eq 1 ]
                  then
                    case $line in
                        $wsp*) printf "%s " "$line" ;;
                        *) printf "%s\n" "$line" ;;
                    esac
                  fi
          esac
          echo "$line"
        done
}

hnum() {
    case ${#1} in
	1|2|3|4) _HNUM=$1 ;;
	5|6) _HNUM=$(( ($1 + 500) / 1000 ))K ;;
	7|8|9) _HNUM=$(( ($1 + 500000) / 1000000 ))M ;;
	10|11|12) _HNUM=$(( ($1 + 500000000) / 1000000000 ))G ;;
	*) _HNUM="HUGE" ;;
    esac
}

popheader()
{
    local ph_num=$1
    local sw=$(( $COLUMNS - 44 - ${#num_messages} ))
    f1= #$scroll_down${HB_RESET}${colour}${cle}
    f2="${f1}%2.1s %${#num_messages}d %6.6s %-25.25s %6.6s %-${sw}.${sw}s${HB_RESET}\r"
    notify reading header $ph_num
    popcmd top $ph_num ${msg_lines:-10} || return 1
    size[$ph_num]=$num
    _POPREAD=`popread x  <&3`
    header=1
    local IFS=$NL
    _POPHEADER=( ${_POPREAD%%$NL$NL} )
    msg_top[$ph_num]=${_POPREAD#*$NL$NL}
    msg_read[$ph_num]=1
    local num=0
    while [ $num -lt ${#_POPHEADER[@]} ]
    do
      line=${_POPHEADER[$num]}
      case $line in
          "") header=0; break ;;
	  [\ \	]*) ;;
          [Ss][Uu][Bb][Jj][Ee][Cc][Tt]:* ) 
	            msg_subject[$ph_num]=${line#*: } ;;
          [Ff][Rr][Oo][Mm]:*) 
                    msg_from[$ph_num]=${line#*: }
		    msg_xfrom[$ph_num]=${msg_from[$ph_num]%%\<*};;
          [Tt][Oo]:*)
                    msg_to[$ph_num]=${line#*: } ;;
          [Cc][Cc]:*)
                    msg_cc[$ph_num]=${line#*: } ;;
	  [Dd][Aa][Tt][Ee]:*)
                    msg_date[$ph_num]=${line#*: } ;;
          [Mm][Ee][Ss][Ss][Aa][Gg][Ee]-[Ii][Dd]:*)
                    msg_id[$ph_num]=${line#*: } ;;
	  [Rr][Ee][Pp][Ll][Yy]-[Tt][Oo]:*)
                    msg_reply_to[$ph_num]=${line#*: } ;;
	  [Ss][Ee][Nn][Dd][Ee][Rr]:*)
	            msg_sender[$ph_num]=${line#*: } ;;
	  *:*) last_type=${line#*: } ;;
      esac
      num=$(( $num + 1 ))
    done
    hnum "${size[$ph_num]}"
    msg_hnum[$ph_num]=$_HNUM
    msg_status[$ph_num]=' '
    summaries[$ph_num]=`printf "$f2" "${msg_status[$ph_num]}" \
                                     "$ph_num" \
                                     "${msg_date[$ph_num]:5:6}" \
                                     "${msg_xfrom[$ph_num]//\"/}" \
                                     "($_HNUM)" "${msg_subject[$ph_num]}"`
    printf "\n%s\n" "${summaries[$ph_num]}"
}

notify() {
    local msg=" $* "
    printat 1 $(( $COLUMNS - ${#msg} - 1 )) "$msg"
}

show_cmd() {
    local n=-1
    local num=${#cmds[@]}
    local cmd=${cmds[*]}
    local cmd_line=$(( $LINES - 1 ))
    justify=$(( ($COLUMNS - ${#cmd}) / (${num} + 1) ))
    commands=
    printat $cmd_line 1 "${BR}"
    printf "%${COLUMNS}s" ' '
    printat $cmd_line 1 
    while [ $(( n += 1 )) -lt $num ]
    do
      initial="${cmds[n]:0:1}"
      the_rest="${cmds[n]:1}"
      commands=$commands$initial
      printf " %${justify:-0}.${justify}s${NA}${B}%s${R}%s${BR}" ' ' $initial "${the_rest}"
    done
    printf "${NA}"
}

show_msg() {
    local num=${1:-1}
    local w=$(( $COLUMNS - 10 ))
    cls
    echo "$CINV"
    printat 1 1; printf "$BR%${COLUMNS}.${COLUMNS}s" " "
    printat 1 1; echo "$BR Message $num of $num_messages$NA"
    printat 2 1; printf "$date_lattr    Date: $date_attr %-${w}.${w}s${NA}" "${msg_date[num]}"
    printat 3 1; printf "$from_lattr    From: $from_attr %-${w}.${w}s${NA}" "${msg_from[num]}"
    printat 4 1; printf "$to_lattr      To: $to_attr %-${w}.${w}s${NA}" "${msg_to[num]}"
    printat 5 1; printf "$subj_lattr Subject: $subj_attr %-${w}.${w}s${NA}" "${msg_subject[num]}"
    printat 7 1
    local IFS=$NL
#    printf "%s\n" "${msg_top[$num]}" | cut -c1-$(( $COLUMNS - 1 )) | head -$(( $LINES - 10 ))
    printf "%s\n" "${msg_top[$num]}" | fold -w $(( $COLUMNS - 1 )) | head -$(( $LINES - 10 ))
}

show_summaries() {
    local msg_num=-1
    cls
    while [ $(( msg_num += 1 )) -lt $num_messages ]
    do
      [ ${msg_read[$msg_num]:=0} -ne 1 ] && popheader $msg_num
    done
    cls
    printat 3 1
    printf "%s\n" "${summaries[@]}" |
    if [ $num_messages -gt $(( $LINES - 10 )) ]
    then
      less
    else
      cat
    fi
    echo
    read -sn1 -p " ${B}Press any key to continue${NA} "
}

set_attr() {
    case $1 in
	-var) var=$2; shift 2 ;;
	-var=*) var=${1#-var=}; shift ;;
	-var*) var=${1#-var}; shift ;;
	*) var= ;;
    esac
    _SET_ATTR=
    for attr
    do
      case $attr in
	  *,*) eval "_SET_ATTR=$_SET_ATTR\${fg_${attr%,*}}\${bg_${attr#*,}}" ;;
          *)  eval "_SET_ATTR=$_SET_ATTR\${fg_${attr}}" ;;
      esac
    done
    [ -n "$var" ] && eval "$var=\"$_SET_ATTR\""
}

cleanup() {
    msg_num=-1
    while [ $(( msg_num += 1 )) -lt $num_messages ]
    do
      [ "${msg_status[$msg_num]}" = D ] && {
	  popcmd dele $msg_num
	  printf "\r${cle}%s\n" "$ok $num $x"
      } # || printf "\r${cle}%s\r" " $num"
    done
    [ ${_CONNECT:-0} -eq 1 ] && popcmd quit
    stty $stty
    stty sane echo
    printf "$NA\r$cles$CVIS"
}

wsp="[ 	]"
bra='['
ket=']'
ESC=$'\e'
NL=$'\n'
CR=$'\r'
TAB=$'\t'
CSI=${ESC}${bra}
cle=${CSI}K
cles=${CSI}J
clbs=${CSI}1J
CVIS="${CSI}?25h"
CINV="${CSI}0;8m"
MSI=${CSI}M
NA=${CSI}0m
B=${CSI}1m
R=${CSI}7m
BR=$B$R
U=${CSI}4m
UP=${CSI}A
DN=${CSI}B
RT=${CSI}C
LF=${CSI}D
mouse_type[0]=${CSI}?9h     ## report mouse button press
mouse_type[1]=${CSI}?1000h  ## report mouse button press and release
mouse_on=${mouse_type[0]}
mouse_off=${CSI}?9l${CSI}?1000l
upper=ABCDEFGHIJKLMNOPQRSTUVWXYZ
lower=abcdefghijklmnopqrstuvwxyz
numeric=0123456789
alphanumeric=$upper$lower$numeric
CVIS=${CSI}?25h
CINV=${CSI}?25l
allkeys=$chars

verbose=0
longusage=0
version="1.0"
copyright=2004
author="Chris F.A. Johnson"
progname=${0##*/}

config_file=$HOME/.pop3ckrc

while getopts vVhH-:c:s var
do
  case $var in
      c) config_file=$OPTARG ;;
      s) pop3stat || return 5
	 printf "\r$_POP3STAT for $user on $pop $cle\n"
	 popcmd quit || exit 4
	 exit ;;
    -) case $OPTARG in
         help) usage; exit ;;
         help_long) longusage=1; usage; exit ;;
         version) version; exit ;;
       esac
       ;;
    h) usage; exit ;;
    H) longusage=1; usage; exit ;;
    v) verbose=$(( $verbose + 1 )) ;;
    V) version; exit ;;
    *);;
  esac
done
shift $(( $OPTIND - 1 ))

cls
stty=`stty -g`
stty -icanon -echo
delete_will_advance=1

[ -f "$config_file" ] || { create_config || exit 5; }
. "$config_file"

setsize() {
    set `stty size || { tput lines; tput cols; }`
    LINES=${1:-24}
    COLUMNS=${2:-80}
    [ -n "$1" ] || show_msg $msg_num
}

trap setsize SIGWINCH

trap cleanup EXIT
echo  "Making connection to $pop as $user"
pop3stat || { echo "$OK $num $x (conection failed)" ; exit 5; }
echo "$_POP3STAT"
[ ${num:-0} -gt 0 ] || { popcmd quit; exit; }

cmds=( forward next back previous goto summary delete undelete quit )

msg_lines=$(( ${LINES} - 6 ))
msg_num=1
while :
do
  setsize
  [ ${msg_read[$msg_num]:=0} -ne 1 ] && popheader $msg_num
  [ ${last_msg:-0} -ne $msg_num ] && show_msg $msg_num
  show_cmd
  last_msg=$msg_num
  get_key "$commands$ESC"
  case $_GET_KEY in
      n|f|$UP|$RT) msg_num=$(( $msg_num + 1 )) ;;
      b|p|$DN|$LF) msg_num=$(( $msg_num - 1 )) ;;
      d)
	  msg_top[$msg_num]="    ${BR}    DELETED    ${NA}"
	  msg_status[$msg_num]=D
	  summaries[$msg_num]=`printf "$f2" "${msg_status[$msg_num]}" $msg_num "${msg_date[$msg_num]}" "${msg_from[$msg_num]//\"/}" "(${msg_hnum[$msg_num]})" "${msg_subject[$msg_num]}"`
	  show_msg $msg_num
	  sleep .2
	  msg_num=$(( $msg_num + ${delete_will_advance:=0} ))
	  ;;
      g) stty echo
	  printat $(( $LINES - 1 )) 1 "$cle"
	  read -ep "$BR Enter number of message:$NA " num
	  stty -echo
	  case $num in
	      *[!0-9]*) printf "\aInvalid entry"
	                sleep 2
                        ;;
              *) msg_num=$num ;;
	  esac
	  ;;
      q) break ;;
      u) msg_status[$msg_num]=U
	  popheader $msg_num
	  show_msg $msg_num
	  ;;
      s) show_summaries
	  show_msg $msg_num
	  ;;
  esac
  if [ $msg_num -lt 1 ]
  then
    msg_num=1
  elif [ $msg_num -ge $num_messages ]
  then
    msg_num=$num_messages
  fi
done

cleanup