#!/bin/bash

set -e

TARGET="$(basename "$(pwd)").tex"

if [ -e "$TARGET" ]; then
    echo "error: '$TARGET' already exists"
    exit 1
fi

files=(*.tex)
if [ "${files[0]}" = "*.tex" ]; then
    echo "error: no .tex files found"
    exit 1
fi
if [ "${#files[@]}" -gt 1 ]; then
    echo "error: multiple .tex files found: ${files[*]}"
    exit 1
fi

mv "${files[0]}" "$TARGET"