#!/usr/bin/env bash
set -euo pipefail

# Check for sudo/root
if [ "$EUID" -ne 0 ]; then
  echo "This script must be run with sudo or as root."
  exit 1
fi

# Determine the real user’s home (so we don't install config into /root)
if [ -n "${SUDO_USER-}" ] && [ "${SUDO_USER}" != "root" ]; then
  USERNAME="${SUDO_USER}"
else
  USERNAME="$(id -un)"
fi
USER_HOME="$(getent passwd "$USERNAME" | cut -d: -f6)"

echo "Installing tmate for user: $USERNAME (home: $USER_HOME)"

# Update package list and install tmate
apt-get update
apt-get install -y tmate

# Prepare config file path
CONFIG="$USER_HOME/.tmate.conf"

# Backup existing config if present
if [ -f "$CONFIG" ]; then
  BACKUP="$CONFIG.bak.$(date +'%Y%m%d%H%M%S')"
  echo "Backing up existing $CONFIG → $BACKUP"
  cp "$CONFIG" "$BACKUP"
fi

# Write new config
cat << 'EOF' > "$CONFIG"
set -g tmate-server-host borohov.net
set -g tmate-server-port 2223
set -g tmate-server-rsa-fingerprint SHA256:F5t1Hh8y7S7e6k/Td6htGUTcB4IDtYfMcN+UPYscLv0
set -g tmate-server-ed25519-fingerprint SHA256:oJ8kl6VOJrHQLyPTNUQrrcPA7OyzuYzkwSCr9uZdHpQ
EOF

# Ensure ownership and permissions
chown "$USERNAME":"$USERNAME" "$CONFIG"
chmod 600 "$CONFIG"

echo "✅ tmate installed and configuration written to $CONFIG"
echo "Start your first session with 'tmate'"