#!/bin/bash

# Exit on error
set -e

# Parse options
LAYOUT="3x4"  # default
while getopts "l:" opt; do
  case ${opt} in
    l ) LAYOUT="$OPTARG" ;;
    \? ) echo "Usage: nup [-l layout] document.typ"; exit 1 ;;
  esac
done
shift $((OPTIND -1))

# Input file
INPUT_FILE="$1"
if [ -z "$INPUT_FILE" ]; then
  echo "Error: No Typst input file provided."
  exit 1
fi

# Filenames and paths
TMPDIR=$(mktemp -d)
BASENAME=$(basename "$INPUT_FILE" .typ)
NUP_FILE="${TMPDIR}/nup_typst_document.typ"
# Absolute path to output
OUTPUT_PDF="$(pwd)/${BASENAME}-nup.pdf"

# Compile original document to SVG pages
typst compile "$INPUT_FILE" "${TMPDIR}/preview{p}.svg"

# Count number of SVG files
NUM_PAGES=$(ls "$TMPDIR"/preview*.svg | wc -l)
UPPER_BOUND=$((NUM_PAGES + 1))

# Generate Typst file to n-up the pages
cat > "$NUP_FILE" <<EOF
#import "@preview/nup:0.1.1": nup
#let pages = range(1, ${UPPER_BOUND}).map(
  i => image("preview" + str(i) + ".svg"))
#nup("${LAYOUT}", pages)
EOF


# Move into TMPDIR and compile the nup document from there
(
  cd "$TMPDIR"
  typst compile "$(basename "$NUP_FILE")" "$OUTPUT_PDF"
)


# Clean up
rm -r "$TMPDIR"

echo "Done! Output written to $OUTPUT_PDF"