Automatic Scanning for paperless-ngx with ASN barcode

scanboi.sh

#!/bin/bash
set -e

# Enable ASN barcode detection: https://docs.paperless-ngx.com/configuration/#barcodes
# https://margau.net/posts/2023-04-16-paperless-ngx-asn/

if [ "$#" -ne 1 ]; then
    echo "Usage: $0 <initial_counter>"
    exit 1
fi

initial_counter=$1
output_dir="."
base_name="ASN"

# Ensure the output directory exists
mkdir -p "$output_dir"

# Initialize the document counter
counter="$initial_counter"

while true; do
    # Create a temporary directory for scanned pages
    temp_dir=$(mktemp -d)

    # Scan using the ADF at 300 DPI
    # scanimage --help --device-name 'brother3:net1;dev0' will get you options
    scanimage --device-name 'brother3:net1;dev0' --mode "True Gray" --source "Automatic Document Feeder(centrally aligned)" -x 210 -y 297 --resolution 300 --batch="$temp_dir/page_%04d.pnm"

    # Convert each scanned page to PDF
    for page_file in "$temp_dir/page_"*.pnm; do
        page_number=$(basename "$page_file" | sed 's/page_\([0-9]\+\)\.pnm/\1/')
        convert "$page_file" -page a4 "$temp_dir/${base_name}${counter}_page${page_number}.pdf"
    done

    # Generate barcode image (QR code)
    barcode_text="${base_name}$(printf "%05d" "$counter")"
    barcode_image="$temp_dir/barcode_${counter}.png"
    qrencode -o "$barcode_image" "$barcode_text"

    # Convert QR code to PDF
    convert "$barcode_image" -page a4 "$temp_dir/${base_name}${counter}_barcode.pdf"

    # Combine all pages into a single PDF
    pdf_files=("$temp_dir/${base_name}${counter}_page"*.pdf "$temp_dir/${base_name}${counter}_barcode.pdf" )
    pdfunite "${pdf_files[@]}" "$output_dir/${base_name}${counter}.pdf"

    # Clean up temporary directory
    rm -r "$temp_dir"

    # Increment the document counter
    ((counter++))

    # Prompt user to add new pages
    read -p "Place the next set of pages in the ADF and press Enter to continue. If you are done, type 'exit' and press Enter: " userInput

    # Check if the user wants to exit
    if [[ "$userInput" == "exit" ]]; then
        echo "Scanning process completed."
        exit 0
    fi
done