#!/usr/bin/env -S hackvr_coproc /bin/bash
#draw a 7x7 grid
#top row gets the day names
#figure out what the first day of the week for that month is
#then looping is easy after that
#use date with format string of day-of-week for an alternate time of the viewing month's first day

### :D atq in my calendar?
# atq files are stored in: /var/spool/cron/atjobs/
# filename format: %1c %5x %8x
# order: queue, job number, time / 60

set -eo pipefail
year=2020
month=2
day=1

cw=30
ch=30

yoff=51
xoff=90
backup=238

printf "%s move %s 0 -%s\n" "$USER" "$xoff" "$backup"

refresh="yep"

stdbuf -oL grep -v '^#' | while true;do
  if [ "$refresh" ];then
    unset refresh
    first_dow="$(date -d $month/1/$year +%w)"
    monthname="$(date -d $month/1/$year +%B)"
    dow=$first_dow
    row=0
    d=1
    days_in_month=$(cal -d "$year-$month" | tr ' ' '\n' | grep . | tail -n1)
    printf "%s %s\n" "${monthname}" "${year}" | makelabel.sh "_MONTH_" $[$xoff / 2] $[$yoff + $ch + 5] 0
    printf "<==\n" | makelabel.sh "_prevmonth_" $[0 - $cw] $[$yoff + $ch + 5] 0
    printf "==>\n" | makelabel.sh "_nextmonth_" $[$xoff * 2 + $cw] $[$yoff + $ch + 5] 0

    while [ "$d" -le "$days_in_month" ];do
#      printf "%s %s : %s\n" "$row" "$dow" "$d"
      if [ -f ~/.local/var/cal/${year}_${month}_${d} ];then
        color=$[4+16]
      else
        color=$[5+16]
      fi
      printf "%s addshape %s 4  %s %s 0  %s %s 0  %s %s 0  %s %s 0\n" \
             "_day_${d}_" "${color}" \
             "$[$dow*$cw]"       "$[-1*$row*$ch + $yoff]" \
             "$[$dow*$cw+$cw-1]" "$[-1*$row*$ch + $yoff]" \
             "$[$dow*$cw+$cw-1]" "$[-1*$row*$ch+$ch-1 + $yoff]" \
             "$[$dow*$cw]"       "$[-1*$row*$ch+$ch-1 + $yoff]"
      printf "%s\n" "${d}" | makelabel.sh "_day_${d}_" "$[$dow*$cw + 1]" "$[-1*$row*$ch + $yoff + 1]" 0
      d=$[$d+1]
      dow=$[$dow + 1]
      if [ $dow = 7 ];then
        dow=0
        row=$[$row + 1]
      fi
    done
    day="$(date +%e | tr -d ' ')"
#    printf "%s move 0 0 3\n" "_${day}_"
  fi
  if ! read group action target;then
    exit
  fi
  #xmessage "$group $action $target"
  if [ "$action" = "action" ];then
    if [ "$target" = "_nextmonth_" ];then
      month=$[month + 1]
      if [ $month = 13 ];then
        month=1
        year=$[$year + 1]
      fi
      refresh="yep"
    fi
    if [ "$target" = "_prevmonth_" ];then
      month=$[month - 1]
      if [ $month = 0 ];then
        month=12
        year=$[$year - 1]
      fi
      refresh="yep"
    fi
    if [ "$target" = "_MONTH_" ];then
      month="$(xmessage -buttons January:1,February:2,March:3,April:4,May:5,June:6,July:7,August:8,September:9,October:10,November:11,December:12 'pick a month';echo $?)"
      refresh="yep"
    fi
    if printf "%s\n" "$target" | grep '^_day_' 2>&1 >/dev/null;then
      d="$(printf "%s\n" "$target" | cut -d_ -f3)"
      file=~/.local/var/cal/${year}_${month}_${d}
      if [ -e "${file}" ];then
        derp=exists
      else
        derp=notexists
      fi
      x-terminal-emulator -e nano "${file}"
      if [ -e "${file}" ];then
        if [ ! -s "${file}" ];then
          rm "${file}"
        fi
      fi
      if [ -e "${file}" ];then
        merp=exists
      else
        merp=notexists
      fi
      if [ "${derp}" != "${merp}" ];then
        refresh="yep"
      fi
    fi
  fi
  if [ "$action" = "quit" ];then
    exit
  fi
  if [ "$refresh" ];then
    ### I /might/ want to just make all of the calendar parts
    ### start with _cal_* so I can deletegroup _cal_*
    ### instead of nuking the world except the user.
    printf "%s deleteallexcept %s\n" "$USER" "$USER"
  fi
done