{ pkgs, ... }:

# exiftool config and script based on that of @numinit

let
  # An exiftool config that adds the OriginTimestamp property containing the best guess for file creation time
  exiftool-config = pkgs.writeText "exiftool.config" ''
    %Image::ExifTool::UserDefined = (
        'Image::ExifTool::Composite' => {
          OriginTimestamp => {
            Desire => {
              0 => 'CreateDate',
              1 => 'DateTimeOriginal',
              2 => 'FileModifyDate'
            },
            ValueConv => '$val[0] || $val[1] || $val[2] || undef',
            PrintConv => '$self->ConvertDateTime($val)',
            PrintConvInv => '$self->InverseDateTime($val)'
          }
        }
      )
    '';

  # A tool to use `find` and `exiftool` to sort images into YMD folders
  sibd = pkgs.writeShellScriptBin "sort-images-by-date" ''
    set -euo pipefail

    if [ $# -lt 3 ]; then
      echo "Usage: $0 [prefix] [src] [dest] [exiftool args...]" >&2
      exit 1
    fi

    prefix="$1"
    src="$2"
    dest="$3"
    # Remove $1, $2, $3 from $@ so the remainder can be passed to exiftool
    shift; shift; shift

    # This find expression matches .jpg/.png modified 14+ days ago.
    # The -not (-name -prune) expressions exclude directories from the results by name.
    # The exiftool command will move matched files to $dest/$prefix/year/month/day/filename.ext.
    #   -config loads the config defined above, which adds the OriginTimestamp composite property
    #   -filename tells exiftool to move each file to a new filename, $OriginTimestamp
    #   -d defines how the timestamp will be converted to a string, which ends up handling the pathing
    ${pkgs.findutils}/bin/find $src \
      -not \( -name FalseKnees -prune \) \
      -not \( -name Background -prune \) \
      -type f \
      -mtime +14 \
      \( -name "*.jpg" -or -name "*.png" \) \
      -exec ${pkgs.exiftool}/bin/exiftool \
        -config ${exiftool-config} \
        -api largefilesupport=1 \
        -progress \
        -filename'<OriginTimestamp' \
        -d "''${dest}/''${prefix}/%Y-%m-%d/%%f%%-c.%%le" \
        "$@" \
        {} +
  '';

  # Script for cron jobs that sends output to journalctl -t sync-pipeline
  sibd-cron = prefix: src: dest: pkgs.writeShellScript "sibd-cron" ''
    ${pkgs.systemd}/bin/systemd-cat -t sync-pipeline ${sibd}/bin/sort-images-by-date ${prefix} ${src} ${dest}
  '';
in {
  environment.systemPackages = [ sibd ];

  services.cron = {
    enable = true;
    systemCronJobs = [
      "0 0 * * 1 tvb ${sibd-cron "nokia" "/home/tvb/phone-sync/DCIM" "/home/tvb/phone-sync/staging"}"
      "0 0 * * 1 tvb ${sibd-cron "nokia" "/home/tvb/phone-sync/Pictures" "/home/tvb/phone-sync/staging"}"
    ];
  };
}