Wrapper to `highlight` tool, with sensible defaults and ease to use on directories

code2rtf

#!/usr/bin/env bash
#
# vim: et ts=4 sw=4 ft=sh:

declare -r SCRIPT_NAME=$0
declare -r THEME_LIGHT="Seashell"
declare -r THEME_DARK="Zenburn"
declare -r TAB_SPACES=4
declare -r LINE_NUMBER_COLUMN_LENGTH=4
declare -r OUTPUT_ENCODING=UTF-8
declare -r OUTPUT_FORMAT=rtf

VERBOSE_IS_ON=false
THEME=$THEME_DARK
SHOW_LINES_ON_OUTPUT=true
OUTPUT_DIRECTORY=

function exit_with_error
{
    echo $1
    exit 2
}

function debug_message
{
    [[ $VERBOSE_IS_ON ]] || exit 0;

    echo $1 >&2
}

function outout_line_numbers_option()
{
    [[ $SHOW_LINES_ON_OUTPUT ]] && echo --line-numbers --line-number-length=$LINE_NUMBER_COLUMN_LENGTH
}

function highligh_using_config
{
    declare -r source=$1
    declare -r destiny=$2

    [[ -z "$source" ]] && exit_with_error 'A "source" file is required to highlight.'
    [[ -z "$destiny" ]] && exit_with_error 'A "destiny" file is required to put highlighted code into.'

    debug_message "Highlighting $source -> $destiny"
    highlight --out-format $OUTPUT_FORMAT -u $OUTPUT_ENCODING -i "$source" -o "$destiny" --style $THEME --replace-tabs $TAB_SPACES $(outout_line_numbers_option)
}

function create_destination_file()
{
    declare -r source=$1
    declare -r desintation="${source}.rtf"

    [[ ! -f $source ]] && exit_with_error 'Source is invalid'
    [[ -f $desintation ]] && rm $desintation

    echo $desintation
}

function fetch_list_of_files_to_highlight
{
    declare -r source=$1

    [[ -z "$source" ]] && exit_with_error 'A "source" is required to fetch files to highlight.'

    debug_message "Identifying source: $source"
    if [ -d $source ]; then
        debug_message "Source is a directory"
        ls -d $source/*
    else
        debug_message "Source is a single file"
        echo $source
    fi

}

function display_usage_information
{
    cat <<- _EOT_
Usage: $SCRIPT_NAME -hv [-o <output directory>] <source>

Uses 'highlight' to convert a code file into a RTF file, which
can be used in presentations, for example. This is just a crude
wrapper to the 'highlight' binary making easier things like:

- Highlighting an entire directory
- Great default configurations, no more looking for help every time
  you need to create those highlights again.
- Switch between dark and light themes.

    Options:

        -v      Verbose mode, display script execution information.
        -h      This help message.
        -d      Uses the dark theme (this is default).
        -l      Uses the light theme.
        -n      Do not show line numbers in output, defaults to show
                them using 4 columns, starting at 0 (zero).

        -o dir  Output RTF files into this directory instead of using
                the same directory of the sources.

_EOT_

    exit 1;
}

function main
{
    declare -r from_source=$1

    [[ -z "$from_source" ]] && display_usage_information

    for from_file in $(fetch_list_of_files_to_highlight $from_source); do
        to_file=$(create_destination_file $from_file)
        highligh_using_config $from_file $to_file
    done

    exit 0;
}

while getopts "vhldno:" OPTION; do
    case $OPTION in
        v)
            VERBOSE_IS_ON=true
            ;;
        h)
            display_usage_information
            ;;
        o)
            exit_with_error 'Custom output diretctory option not implemented.'
            [[ -z "$OPTARG" ]] && exit_with_error 'An output directory is required for option "-o <output directory>".'
            [[ ! -d "$OPTARG" ]] && exit_with_error 'Output directory being used is not a directory.'

            OUTPUT_DIRECTORY=$OPTARG
            ;;
        d)
            THEME=$THEME_DARK
            ;;
        l)
            THEME=$THEME_LIGHT
            ;;
        n)
            SHOW_LINES_ON_OUTPUT=false
            ;;
    esac
done

# Sets the action as the last parameter avaiable (Dirty hack)
for INPUT; do true; done
main $INPUT

exit 0;

Note to self: I love the fact the I wrote this less than the fact that I wrote that help message. 😍