environment variables helper script

env.sh

#!/usr/bin/env bash
# Usage:
# --- .env file creation mode (will be created from provided files):
# env.sh f .env.dist .another.env.dist
# --- command mode (will be run with exported variables):
# env.sh c subcommand

if [[ $1 == "f" ]]; then
    if [[ -z "$2" ]]; then
        echo -e "\033[31mProvide at least one .env.dist file name\033[0m"
        exit 1
    fi
    variables=()
    for arg in "${@:2}"; do
        if [[ ! -f "$arg" ]]; then
            echo -e "\033[2mThere is no file named $arg\033[0m"
            continue
        fi

        while IFS= read -r line; do
            if [[ ! "$line" =~ ^[a-zA-Z_0-9]+=.* ]]; then
                continue
            fi

            line_var=($(echo $line | tr "=" "\n"))
            var_found=0

            for var in "${variables[@]}"; do
                if [[ $var == "${line_var[0]}" ]]; then
                    var_found=1
                fi
            done

            if [[ "$var_found" == "0" ]]; then
                variables+=(${line_var[0]})
            fi

            declare "variable_${line_var[0]}=${line_var[1]}"
        done < $arg
    done

    IFS=$'\n' sorted=($(sort <<<"${variables[*]}")); unset IFS
    > .env
    for var in "${sorted[@]}"; do
        name="variable_${var}"
        echo "${var}=${!name}" >> .env
    done

elif [[ $1 == "c" ]]; then
    if [[ ! -f ".env" ]]; then
        echo -e "\033[31mThere is no .env file\033[0m"
        exit 1
    fi

    export $(cat .env) && ${@:2}

else
    echo -e "\033[31mProvide mode name (f | c)\033[0m"
    exit 1
fi