Python virtual environment list and activation script

environ

ROOT=~/venv
RED='\e[0;31m'
GREEN='\e[0;32m'
LIGHTBLUE='\e[1;34m'
NC='\e[0m' # No Color

trim() {
  # Remove the leading and trailing whitespaces
  # https://stackoverflow.com/a/12973694
  echo $1 | xargs
}

printEnvList() {
    echo "Environment list:"
    for env in "${!venvs[@]}"; do
        echo -en "- ${GREEN}$env${venvs[$env]}${NC}"
        [[ -f $ROOT/$env/motd ]] && echo " - "`cat $ROOT/$env/motd` || echo
    done
}

banner() {
    # Show text in a frame
    # https://unix.stackexchange.com/a/250094
    msg="$*"
    edg=$(echo "$msg" | sed 's/./─/g')
    echo "┌─$edg─┐"
    echo "│ $msg │"
    echo "└─$edg─┘"
}

unset venvs # required when called using `source` command
declare -A venvs

for f in $ROOT/*; do
    # [[ -e $f ]] || continue
    if [[ -L $f ]]; then
        src_dir=$(readlink $f)
        alias_name=$(basename $f)
        if [[ -f $src_dir/bin/activate ]]; then
            venvs[`basename $src_dir`]+=" | $alias_name"
        else echo -e "${RED}!! $src_dir ($alias_name) is not a virtual environment${NC}"
        fi
    elif [[ -d $f ]]; then
        if [[ -f $f/bin/activate ]]; then
            venvs[`basename $f`]+=""
        else echo -e "${RED}!! $f is not a virtual environment${NC}"
        fi
    fi
done

if [[ -z $1 ]]; then
    echo -e "Environment search path: ${GREEN}$ROOT${NC}"
    echo "Usage:"
    echo -e "- ${GREEN}. environ${NC} - show help and environment list"
    echo -e "- ${GREEN}. environ ENV_NAME${NC} - activate environment"
    #                                       https://stackoverflow.com/a/38462237
    echo -e "- ${GREEN}echo \"some text\" > $(cd "$ROOT" && dirs)/ENV_NAME/motd${NC} - set environment description"
    echo
    printEnvList
elif [[ -f $ROOT/$1/bin/activate ]]; then
    echo -e "${LIGHTBLUE}Activating $1 virtual environment...${NC}"
    [[ -f $ROOT/$1/motd ]] && banner `cat $ROOT/$1/motd`
    command -v deactivate &> /dev/null && deactivate
    source $ROOT/$1/bin/activate
else echo -e "${RED}Error: Virtual environment \"$1\" not found${NC}"
fi