#!/usr/bin/env bash

# check_is_installed checks to see if the supplied executable is installed and
# exits if not. An optional second argument is an extra message to display when
# the supplied executable is not installed.
#
# Usage:
#
#   check_is_installed PROGRAM [ MSG ]
#
# Example:
#
#   check_is_installed kind "You can install kind with the helper scripts/install-kind.sh"
check_is_installed() {
    local __name="$1"
    local __extra_msg="$2"
    if ! is_installed "$__name"; then
        echo "FATAL: Missing requirement '$__name'"
        echo "Please install $__name before running this script."
        if [[ -n $__extra_msg ]]; then
            echo ""
            echo "$__extra_msg"
            echo ""
        fi
        exit 1
    fi
}

is_installed() {
    local __name="$1"
    if $(which $__name >/dev/null 2>&1); then
        return 0
    else
        return 1
    fi
}

# vpc_id fetches the vpc id of the GitHub Actions runner/EC2 instance.
# vpc id is needed for setting up AWS CloudMap namespaces
vpc_id() {
    local __md_url="http://169.254.169.254/latest/meta-data/network/interfaces"
    local __macid=$( curl ${__md_url}/macs/ || exit 1 )
    local __vpcid=$( curl ${__md_url}/macs/${__macid}vpc-id || exit 1 )
    echo "$__vpcid"

}

DEFAULT_DEBUG_PREFIX="DEBUG: "

# debug_msg prints out a supplied message if the DEBUG environs variable is
# set. An optional second argument indicates the "indentation level" for the
# message. If the indentation level argument is missing, we look for the
# existence of an environs variable called "indent_level" and use that
debug_msg() {
    local __msg=${1:-}
    local __indent_level=${2:-}
    local __debug="${DEBUG:-""}"
    local __debug_prefix="${DEBUG_PREFIX:-$DEFAULT_DEBUG_PREFIX}"
    if [ ! -n "$__debug" ]; then
        return 0
    fi
    __indent=""
    if [ -n "$__indent_level" ]; then
        __indent="$( for each in $( seq 0 $__indent_level ); do printf " "; done )"
    fi
    echo "$__debug_prefix$__indent$__msg"
}