#!/bin/sh

PATH=/live/bin:/bin
dir=/live/custom/tao

main() {
    local idx=$(shuf -n1 $dir/tao.idx)
    : ${idx:=0}

    IFS=''
    local cnt=0
    tail -n $idx $dir/tao.txt | while read -r line; do
        case $line in
            [1-9]*|BOOK*|\([IV]*) cnt=$((cnt + 1))
        esac
        [ $cnt -gt 1 ] && break
        echo "$line"
    done
}

# tac tao.txt | egrep -n "^([1-9]|BOOK|\([IV])" | cut -d: -f1 > tao.idx

main

