make table in bash

table.sh

#!/bin/bash

# the script to make tables like this
# +----------+--------+--------------------+
# |col1      |col2    |col3                |
# +----------+--------+--------------------+
# |val1      |val3    |val4                |
# +----------+--------+--------------------+
# |valqeefnkl|val3wekj|val4                |
# |1         |bkjwvsaj|                    |
# |          |bvjwsvbj|                    |
# |          |bwvjkbjw|                    |
# |          |dvbjwevb|                    |
# |          |wjvbvwkj|                    |
# |          |vjkvsbj |                    |
# +----------+--------+--------------------+



column_len=( 10 8 20 )


table_vertical_separator="|"
table_horizontal_separator="-"
table_border_mark="+"
empty_element="\n"


write_separate_line() {
        for n in "${column_len[@]}"
        do
        echo -n $table_border_mark
        for i in $(seq 1 $n); do echo -n $table_horizontal_separator; done
        done
        echo -n $table_border_mark
        echo ""
}



write_row() {
        printed=""
        recurse=""
        remaining_cols=()
        ci=0
        echo -n $table_vertical_separator
        while (( "$#" )); do
                value=$1
                if [ $value = "$empty_element" ]; then value=""; fi
                remaining=${column_len[ci]}
                size=${#value}
                substr=$empty_element
                if [ "$size" -gt "$remaining" ]; then
                    let "start=remaining+1"
                    substr=`echo "$value" | cut -c$start-$size`
                    value=`echo "$value" | cut -c1-$remaining`
                    recurse="yes"
                fi
                remaining_cols+=($substr)
                echo -n $value
                let "remaining-=size"
                for i in $(seq 1 $remaining); do echo -n " "; done
                echo -n $table_vertical_separator
                let "ci+=1"
                shift
        done

        while [ $ci -lt "${#column_len[@]}" ]
        do
            remaining=${column_len[ci]}
            for i in $(seq 1 $remaining); do echo -n " "; done
            echo -n $table_vertical_separator
            let "ci+=1"
        done

        echo ""
        if [ ! -z "$recurse" ]
        then
        write_row "${remaining_cols[@]}"
        fi

}


make_table() {
        write_separate_line
        write_row "col1" "col2" "col3"
        write_separate_line
        write_row "val1" "val3" "val4"
        write_separate_line
        write_row "valqeefnkl1" "val3wekjbkjwvsajbvjwsvbjbwvjkbjwdvbjwevbwjvbvwkjvjkvsbj" "val4"
        write_separate_line
}


make_table