#!/bin/bash

set -e

# Vérification des variables d'environnement requises
if [ -z "${SSH_HOST}" ] || [ -z "${SSH_USER}" ] || [ -z "${REMOTE_PORTS}" ] || [ -z "${LOCAL_PORTS}" ]; then
  echo "ERROR: Required variables (SSH_HOST, SSH_USER, REMOTE_PORTS, LOCAL_PORTS) are missing."
  exit 1
fi

# Vérification des paramètres de Tailscale
if [ -z "${TAILSCALE_PARAM}" ] && [ -z "${TAILSCALE_AUTH_KEY}" ]; then
  echo "ERROR: Either TAILSCALE_PARAM or TAILSCALE_AUTH_KEY must be set."
  exit 1
fi

# Démarrage de Tailscale en arrière-plan
echo "Starting Tailscale..."
exec tailscaled --state=/var/lib/tailscale/tailscaled.state --socket=/var/run/tailscale/tailscaled.sock &

# Attendre que le service Tailscale démarre
sleep 5

# Construction de la commande Tailscale
TS_CMD="tailscale up"

if [ -n "${TAILSCALE_AUTH_KEY}" ]; then
  TS_CMD="${TS_CMD} --auth-key=${TAILSCALE_AUTH_KEY}"
fi

if [ -n "${TAILSCALE_PARAM}" ]; then
  TS_CMD="${TS_CMD} ${TAILSCALE_PARAM}"
fi

# Affichage de la commande avant exécution
echo "Connecting to Tailscale with: ${TS_CMD}"

# Exécution sécurisée avec `eval` et capture des erreurs
if ! eval "${TS_CMD}"; then
  echo "ERROR: Tailscale failed to start."
  exit 1
fi

# Vérifier que Tailscale est bien actif
if ! tailscale status; then
  echo "ERROR: Tailscale is not running."
  exit 1
fi

# Copier la clé SSH
if [ -f "/tmp/id_rsa" ]; then
    echo "Copying SSH key..."
    cp /tmp/id_rsa /root/.ssh/id_rsa
    chmod 600 /root/.ssh/id_rsa
else
    echo "ERROR: SSH key is missing. Please mount your private key to /tmp/id_rsa."
    exit 1
fi

# Nettoyage des logs au démarrage
echo "" > /var/log/ssh-tunnel/tunnel.log

# Générer la configuration logrotate
envsubst < /logrotate.template > /etc/logrotate.d/ssh-tunnel

# Construire la commande de tunnel SSH
TUNNEL_CMD=""
REMOTE_PORT_ARRAY=(${REMOTE_PORTS})
LOCAL_PORT_ARRAY=(${LOCAL_PORTS})

for i in "${!LOCAL_PORT_ARRAY[@]}"; do
  TUNNEL_CMD="${TUNNEL_CMD} -L 0.0.0.0:${LOCAL_PORT_ARRAY[$i]}:${REMOTE_PORT_ARRAY[$i]}"
done

echo "Starting SSH tunnel to ${SSH_USER}@${SSH_HOST}"
echo "Configured tunnels:"
for i in "${!LOCAL_PORT_ARRAY[@]}"; do
  echo "- ${LOCAL_PORT_ARRAY[$i]} -> ${REMOTE_PORT_ARRAY[$i]}"
done

# Démarrer autossh pour maintenir le tunnel actif
exec autossh -M 0 \
  -o "StrictHostKeyChecking=no" \
  -o "UserKnownHostsFile=/dev/null" \
  -o "ServerAliveInterval=60" \
  -o "ServerAliveCountMax=3" \
  -o "Compression=yes" \
  -N ${TUNNEL_CMD} ${SSH_USER}@${SSH_HOST}