#!/usr/bin/env bash

# global variables

# functions

function bashrc_count_lines {
    wc -l "$HOME/.bashrc" | cut -d' ' -f1
}

function bashrc_watch_start {
    if [[ -z "${BASHRC_LINES+set}" ]]; then
        BASHRC_LINES=$(bashrc_count_lines)
    fi
}

function bashrc_watch_end {
    bashrc_lines=$(bashrc_count_lines)
    if [[ "$BASHRC_LINES" -lt "$bashrc_lines" ]]; then
        echo
        echo '*****************************'
        echo '* BASHRC has evolved        *'
        echo '* please execute:           *'
        echo '*                           *'
        echo "*   source \$HOME/.bashrc    *"
        echo '*                           *'
        echo '*****************************'
        echo
    fi
}

function bashrc_env_sync {
    env_var="$1"
    env_value="$2"
    if printenv | grep -q "$env_var"; then
        real_value=$(eval "echo \$$env_var")
        echo "success for $env_var = $real_value"
    else
        session_line="export ${env_var}=${env_value}"
        append_or_replace "^${session_line}.*" "$session_line" "$HOME/.bashrc" &>/dev/null
        eval "$session_line"
        set +e
        eval "BASHRC_LINES=$BASHRC_LINES $0"
        exit $?
    fi
}

# main

set -Eeu
bashrc_watch_start

echo 'init'
bashrc_env_sync 'SESSION_RESTART' true
echo 'end'

bashrc_watch_end