#!/usr/bin/env bash

set -euo pipefail
if [[ "${TRACE-0}" == "1" ]]; then
  set -o xtrace
fi

# Colors
color_reset="\033[0m"
color_red="\033[0;31m"
color_green="\033[0;32m"
color_yellow="\033[0;33m"
color_bright_black="\033[1;30m"

# Help message
print_help() {
  echo "Usage: ./server-stats.sh [OPTIONS...]"
  echo "  -h  --help  Print help"
}

# Early argument parsing
case "${1:-}" in
"-h" | "--help")
  print_help
  exit 0
  ;;
"")
  # do script below
  ;;
*)
  echo -e "${color_red}unrecognized option: ${1}${color_reset}" >&2
  echo "" >&2
  print_help >&2
  exit 1
  ;;
esac

# System stats
cpu_total=$(LC_ALL=C top -bn1 | awk '/Cpu\(s\)/ {printf "%.0f", 100 - $8}')
read -r ram_total ram_used <<<"$(free --mebi | awk '/Mem:/ {print $2, $3}')"
ram_percentage=$(awk "BEGIN {printf \"%d\", ($ram_used/$ram_total)*100}")
read -r disk_total disk_used disk_percentage <<<"$(LC_ALL=C df --human-readable / | awk 'NR==2{print $2, $3, $5}')"
disk_percentage="${disk_percentage%\%}"

# Tops
top_cpu=$(ps -e --format comm --sort=-%cpu | head -6 | tail -5)
top_ram=$(ps -e --format comm --sort=-%mem | head -6 | tail -5)

# System info
os_version=$(grep '^PRETTY_NAME=' /etc/os-release | cut -d= -f2 | tr -d '"')
uptime=$(uptime --pretty)
load_avg=$(uptime | awk -F'load average:' '{print $2}' | sed 's/^ //')
users_logged_in=$(who | awk '{print $1}' | sort -u | paste -sd ", ")

### Failed login attempts
# if [ -f /var/log/auth.log ]; then
#   failed_logins=$(grep -ci "Failed password" /var/log/auth.log)
#   last_failed=$(grep -i "Failed password" /var/log/auth.log | tail -3 | sed 's/^/      /')
# elif [ -f /var/log/secure ]; then
#   failed_logins=$(grep -ci "Failed password" /var/log/secure)
#   last_failed=$(grep -i "Failed password" /var/log/secure | tail -3 | sed 's/^/      /')
# else
#   failed_logins="N/A"
#   last_failed="Log file not found"
# fi

# Conditional display
if ((cpu_total > 85)); then
  cpu_color=$color_red
elif ((cpu_total > 70)); then
  cpu_color=$color_yellow
else
  cpu_color=$color_green
fi

if ((ram_percentage > 85)); then
  ram_color=$color_red
elif ((ram_percentage > 70)); then
  ram_color=$color_yellow
else
  ram_color=$color_green
fi

if ((disk_percentage > 85)); then
  disk_color=$color_red
elif ((disk_percentage > 70)); then
  disk_color=$color_yellow
else
  disk_color=$color_green
fi

# Output
echo -e "${color_bright_black}╭───────────────── System stats ─────────────────╮${color_reset}"
echo -e "   CPU Usage:  ${cpu_color}${cpu_total}%${color_reset}"
echo -e "   RAM Usage:  ${ram_color}${ram_used}/${ram_total} MB (${ram_percentage}%)${color_reset}"
echo -e "   Disk Usage: ${disk_color}${disk_used}/${disk_total} (${disk_percentage}%)${color_reset}"
echo -e "${color_bright_black}├───────── Top 5 Processes by CPU usage ─────────┤${color_reset}"
echo "${top_cpu}" | awk '{printf "   %d. %s\n", NR, $0}'
echo -e "${color_bright_black}├───────── Top 5 Processes by RAM usage ─────────┤${color_reset}"
echo "${top_ram}" | awk '{printf "   %d. %s\n", NR, $0}'
echo -e "${color_bright_black}├────────────── System information ──────────────┤${color_reset}"
echo "   OS Version:      ${os_version}"
echo "   Uptime:          ${uptime}"
echo "   Load Average:    ${load_avg}"
echo "   Logged in Users: ${users_logged_in}"
# echo -e "${color_bright_black}├──────────── Failed login attempts ─────────────┤${color_reset}"
# echo "   Failed logins: ${failed_logins}"
# echo "   Last failed:   ${last_failed}"
echo -e "${color_bright_black}╰────────────────────────────────────────────────╯${color_reset}"

exit 0