#!/bin/bash
arc_name=$1
dir_name=${arc_name%.*}

ncores=$(nproc)
declare -A hsh_cmd_t=(
        ['7-zip']='7za x -bd -mmt%d %s >/dev/null 2>&1'
        ['cr-unzip']='CRYSTAL_WORKERS=%d cr-unzip %s'
)

for method in "${!hsh_cmd_t[@]}"; do
    echo ">>>>>> Using method: $method <<<<<<"
    cmd_t=${hsh_cmd_t[$method]}
    for ((nw=2; nw<=ncores; nw+=2)); do
            echo "=== $nw workers: ==="
            rm -rf "$dir_name"
            [[ -d $dir_name ]] && { 
                echo "failed to remove $dir_name directory" >&2
                exit 1
            }
            eval 'time '$(printf "$cmd_t" $nw $arc_name)
    done
done