Comma-based CSV file reader for .bashrc

.bashrc

# Bash utility aliases/functions to read huge CSV files
# The both functions read the first n lines from a file

# Normal version (open the columnized file in less)
readcsv() {
    local lines=$1 \
          filename=$2
    head -n "$lines" "$filename" | column -tns ',' | less -S
}

# Improved version 
# (colorized, allows reverse reading as optional arg, and number of lines as optional arg)
readccsv() {
    local filename
    local lines
    local reverse=false
    local delimiter=','

    while [ "$#" -gt 0 ]; do
        case "$1" in
            -r|--reverse)
                reverse=true
                shift
                ;;
            -d|--delimiter)
                if [ -n "$2" ]; then
                    delimiter="$2"
                    shift 2
                else
                    echo "Error: Missing argument for delimiter option."
                    return 1
                fi
                ;;
            *)
                if [ -z "$filename" ]; then
                    filename="$1"
                elif [ -z "$lines" ]; then
                    lines="$1"
                else
                    echo "Invalid argument: $1"
                    return 1
                fi
                shift
                ;;
        esac
    done

    if [ -z "$filename" ]; then
        echo "Usage: readccsv [-r|--reverse] [-d|--delimiter <delimiter>] <filename> [lines]"
        return 1
    fi

    if [ "$reverse" = true ]; then
        tail -n "${lines:-$(wc -l < "$filename")}" "$filename"
    else
        head -n "${lines:-$(wc -l < "$filename")}" "$filename"
    fi | awk -F"$delimiter" '{
        num_columns = NF;  # Get the number of columns from the input
        for (i = 1; i <= num_columns; i++) {
            color = 30 + (i%8);  # Set color based on column number
            printf "\033[1;%dm%s\t\033[00m", color, $i;
        }
        printf "\n";
    }' | column -s$'\t' -t | less -SRN
}