#!/usr/bin/env bash
sleep 0.2 # let wezterm catch up
COLUMNS=$(tput cols)

line() {
  i=1
  while [[ $i -le $COLUMNS ]]; do
    echo -en "\U1FB$((RANDOM % 3))$((RANDOM % 8+1))"
    i=$((i + 1))
  done
}

print-line() {
  awk -v columns="$COLUMNS" -v s="$(line)" \
    'BEGIN{
      for (colnum = 0; colnum<columns+1; colnum++) {
        r = 255-(colnum*255/columns);
        g = (colnum*510/columns);
        b = (colnum*255/columns);
        if (g>255) g = 510-g;
        printf "\033[38;2;%d;%d;%d;49m", r,g,b;
        printf "%s\033[0m", substr(s,colnum+1,1);
      }
      printf "\n";
    }'
}

print-line
print-line