#!/bin/sh
# Identité + réseau : hostname, /etc/hosts, IP statique (ifupdown drop-in).
# Le changement d'IP s'applique AU REBOOT (on ne coupe jamais SSH en live).
# Sauvegardes horodatées avant toute écriture. Échec contrôlé.
export LC_ALL=C
HOST="{{newHostname}}"
DOMAIN="{{domain}}"
IFACE="{{interfaceName}}"
ADDR="{{staticAddress}}"
GW="{{gateway}}"
DNS="{{dnsNameservers}}"
echo "===SU:CUSTOM_IDENTITY==="

# --- Sauvegardes ---
TS=$(date +%s)
cp -a /etc/hosts "/etc/hosts.su.bak.${TS}" 2>/dev/null
[ -f /etc/network/interfaces ] && cp -a /etc/network/interfaces "/etc/network/interfaces.su.bak.${TS}" 2>/dev/null
[ -f /etc/hostname ] && cp -a /etc/hostname "/etc/hostname.su.bak.${TS}" 2>/dev/null

echo "OLD_ENDPOINT={{dhcpEndpoint}}"

# --- Hostname (immédiat, ne coupe pas SSH) ---
if hostnamectl set-hostname "$HOST" 2>/dev/null || { printf '%s\n' "$HOST" > /etc/hostname; }; then
  printf '%s\n' "$HOST" > /etc/hostname
  echo "HOSTNAME_SET=$HOST"
  echo "FILE_MODIFIED=/etc/hostname"
else
  echo "ERR=hostname_failed"
fi

# --- /etc/hosts : ligne 127.0.1.1 <fqdn> <host> ---
FQDN="$HOST"
[ -n "$DOMAIN" ] && FQDN="$HOST.$DOMAIN"
if grep -qE '^127\.0\.1\.1' /etc/hosts 2>/dev/null; then
  sed -i -E "s|^127\.0\.1\.1.*|127.0.1.1\t${FQDN} ${HOST}|" /etc/hosts && echo "FILE_MODIFIED=/etc/hosts"
else
  printf '127.0.1.1\t%s %s\n' "$FQDN" "$HOST" >> /etc/hosts && echo "FILE_MODIFIED=/etc/hosts"
fi

# --- IP statique (ifupdown drop-in, appliqué au reboot) ---
if ip link show "$IFACE" >/dev/null 2>&1; then
  echo "IFACE_OK=$IFACE"
  mkdir -p /etc/network/interfaces.d
  # S'assure que le fichier principal source le répertoire interfaces.d.
  if [ -f /etc/network/interfaces ] && ! grep -qE '^[[:space:]]*source(-directory)?[[:space:]]+/etc/network/interfaces\.d' /etc/network/interfaces; then
    printf '\nsource /etc/network/interfaces.d/*\n' >> /etc/network/interfaces
  fi
  # Neutralise (commente) toute strophe existante de l'interface dans le fichier principal.
  if [ -f /etc/network/interfaces ]; then
    awk -v IFACE="$IFACE" '
      $0 ~ "^[[:space:]]*(auto|allow-hotplug)[[:space:]]+" IFACE "([[:space:]]|$)" { print "#SU# " $0; next }
      $0 ~ "^[[:space:]]*iface[[:space:]]+" IFACE "([[:space:]]|$)" { inblk=1; print "#SU# " $0; next }
      inblk==1 && $0 ~ /^[[:space:]]+[^[:space:]]/ { print "#SU# " $0; next }
      inblk==1 { inblk=0 }
      { print }
    ' /etc/network/interfaces > /etc/network/interfaces.su.tmp && cat /etc/network/interfaces.su.tmp > /etc/network/interfaces && rm -f /etc/network/interfaces.su.tmp
  fi
  # Écrit la configuration statique en drop-in.
  {
    echo "auto $IFACE"
    echo "iface $IFACE inet static"
    echo "    address $ADDR"
    echo "    gateway $GW"
    [ -n "$DNS" ] && echo "    dns-nameservers $DNS"
  } > "/etc/network/interfaces.d/${IFACE}.cfg"
  echo "FILE_MODIFIED=/etc/network/interfaces.d/${IFACE}.cfg"
  echo "STATIC_TARGET=$ADDR gw $GW dns $DNS"
else
  echo "ERR=interface_not_found"
fi

echo "NEW_ENDPOINT={{reconnectHost}}"
echo "RECONNECT_REQUIRED=1"
echo "NETWORK_APPLIES_ON=reboot"
{{#rebootAfterInstall}}echo "REBOOT_REQUESTED=1"{{/rebootAfterInstall}}
echo "===SU:EXIT=0==="