December naptár

#!/bin/bash

function dec() {
  echo
  echo "$1 December"
  echo "  H  K Sz Cs  P Szo V"
  # elseje hanyadik nap a heten?
  els=$(date -d $1-12-01 +'%u')
  # 1=hetfo, 7=vasarnap
  case $els in
  1) echo "  1  2  3  4  5  6  7"; kov=8;;
  2) echo "     1  2  3  4  5  6"; kov=7;;
  3) echo "        1  2  3  4  5"; kov=6;;
  4) echo "           1  2  3  4"; kov=5;;
  5) echo "              1  2  3"; kov=4;;
  6) echo "                 1  2"; kov=3;;
  7) echo "                    1"; kov=2;;
  esac
  het=""
  hn=0
  for (( nap=kov; nap<=31; nap++ )) do
    printf -v het "$het %2d" $nap
    hn=$((hn+1))
    if [ $hn = 7 ]; then
      echo "$het"
      het=""
      hn=0
    fi
  done
  if [ -n "$het" ]; then echo "$het"; fi
}

for (( ev=2000; ev<=$1; ev++ )) do
  clear
  dec $ev
  sleep 3
done