#!/bin/bash
set -e
OldDir="$(pwd)"
cd "$(dirname "$0")"
if ! [ -e bookmark.txt ]; then
    echo "Please run $(dirname "$0")/init first to initialise the book"
    exit 1; fi
N=$[ "$(cat bookmark.txt)" + 1 ]
if [ "$(cat bookmark.txt)" -gt "$(wc -l < one-section-per-line.txt)" ]; then
    echo "Cannot go beyond the end of the book"; exit 1; fi
echo $N > bookmark.txt
cd "$OldDir"
$(dirname "$0")/read