{ pkgs, lib, config, specialArgs, options, modulesPath }:

with pkgs;

let

    pastebin = (writeShellApplication {
        name = "pb";
        runtimeInputs = [ curl ];
        text = ''
        #!/bin/sh

        # init variables
        version="v2020.10.27"
        ENDPOINT="https://stp.cx"
        flag_options=":hvcufe:s::"
        flag_version=0
        flag_help=0
        flag_file=0
        flag_url=0
        flag_colors=0
        flag_ext=0
        data=""
        EXT=""

        # help message available via func
        show_help() {
          cat > /dev/stdout << END
        pb [options] filename
        or
        (command-with-stdout) | pb

        Uploads a file or data to steph's 0x0 paste bin

        OPTIONAL FLAGS:
          -h                        Show this help
          -v                        Show current version number
          -f                        Explicitly interpret stdin as filename
          -c                        Pretty color output
          -u                        Shorten URL
          -s server_address         Use alternative pastebin server address
          -e bin_extension          Specify a binary file extension used in the upload
        END
        }

        show_usage() {
          cat > /dev/stdout << END
        usage: pb [-hfvcux] [-s server_address] filename
        END
        }

        # helper for program exit, supports error codes and messages
        die () {
          msg="$1"
          code="$2"
          # exit code defaults to 1
          if printf "%s" "''${code}" | grep -q '^[0-9]+$'; then
            code=1
          fi
          # output message to stdout or stderr based on code
          if [ -n "''${msg}" ]; then
            if [ "''${code}" -eq 0 ]; then
              printf "%s\\n" "''${msg}"
            else
              printf "%s%s%s\\n" "$ERROR" "''${msg}" "$RESET" >&2
            fi
          fi
          exit "''${code}"
        }

        # attempt to parse options or die
        if ! parsed=$(getopt ''${flag_options} "$@"); then
          printf "pb: unknown option\\n"
          show_usage
          exit 2
        fi

        # handle options
        eval set -- "''${parsed}"
        while true; do
          case "$1" in
            -h|?)
              flag_help=1
              ;;
            -v)
              flag_version=1
              ;;
            -c)
              flag_colors=1
              ;;
            -f)
              flag_file=1
              ;;
            -e)
              shift
              flag_ext=1
              EXT="$1"
              ;;
            -s)
              shift
              ENDPOINT="$1"
              ;;
            -u)
              flag_url=1
              ;;
            --)
              shift
              break
              ;;
            *)
              die "Internal error: $1" 3
              ;;
          esac
          shift
        done

        # display current version
        if [ ''${flag_version} -gt 0 ]; then
          printf "%s\\n" "''${version}"
          die "" 0
        fi

        # display help
        if [ ''${flag_help} -gt 0 ]; then
          show_help
          die "" 0
        fi

        # is not interactive shell, use stdin
        if [ -t 0 ]; then
          flag_file=1
        else
          if [ ''${flag_ext} -gt 0 ]; then
            # short-circuit stdin access to ensure binary data is transferred to curl
            curl -sF"file=@-;filename=null.''${EXT}" "''${ENDPOINT}" < /dev/stdin
            exit 0
          else
            data="$(cat < /dev/stdin )"
          fi
        fi

        # if data variable is empty (not a pipe) use params as fallback
        if [ -z "$data" ]; then
          data="$*"
        fi

        # Colors
        if [ ''${flag_colors} -gt 0 ]; then
          SUCCESS=$(tput setaf 190)
          ERROR=$(tput setaf 196)
          RESET=$(tput sgr0)
        else
          SUCCESS=""
          ERROR=""
          RESET=""
        fi

        # URL shortening reference

        # If URL mode detected, process URL shortener and end processing without
        # checking for a file to upload to the pastebin
        if [ ''${flag_url} -gt 0 ]; then

          if [ -z "''${data}" ]; then
            # if no data
            # print error message
            printf "%sProvide URL to shorten%s\\n" "$ERROR" "$RESET"
          else
            # shorten URL and print results
            result=$(curl -sF"shorten=''${data}" "''${ENDPOINT}")
            printf "%s%s%s\\n" "$SUCCESS" "$result" "$RESET"
          fi
          die "" 0
        fi

        if [ ''${flag_file} -gt 0 ]; then
          # file mode
          if [ -z "''${data}" ]; then
            # if no data
            # print error message
            printf "%sProvide data to upload%s\\n" "$ERROR" "$RESET"
          elif [ ! -f "''${data}" ]; then
            # file not found with name provided
            # print error messagse
            printf "%s%s%s\\tFile not found.%s\\n" "$RESET" "''${data}" "$ERROR" "$RESET"
            # attempt to split data string (multi-line?) and upload each string as file
            for f in ''${data}; do
              # if there's nothing to parse, skip this loop
              if [ "$f" = "$data" ]; then
                break;
              fi
              # check if file exists
              if [ -f "''${f}" ]; then
                if [ ''${flag_ext} -gt 0 ]; then
                  # send file to endpoint masked with new extension
                  result=$(curl -sF"file=@''${f};filename=null.''${EXT}" "''${ENDPOINT}")
                else
                  # send file to endpoint
                  result=$(curl -sF"file=@''${f}" "''${ENDPOINT}")
                fi
                printf "%s%s%s\\n" "$SUCCESS" "$result" "$RESET"
              else
                # print error message
                printf "%sFile not found.%s\\n" "$ERROR" "$RESET"
              fi
            done
          else
            # data available in file
            # send file to endpoint
            result=$(curl -sF"file=@''${data}" "''${ENDPOINT}")
            printf "%s%s%s\\n" "$SUCCESS" "$result" "$RESET"
          fi
        else
          # non-file mode
          if [ -z "''${data}" ]; then
            # if no data
            # print error message
            printf "%sNo data found for upload. Please try again.%s\\n" "$ERROR" "$RESET"
          else
            # data available
            # send data to endpoint
            result=$(printf "%s" "''${data}" | curl -sF"file=@-;filename=null.txt" "''${ENDPOINT}")
            printf "%s%s%s\\n" "$SUCCESS" "$result" "$RESET"
          fi
        fi


        '';
    });

in
{
  environment.systemPackages = [ pastebin ];
}