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

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PACKAGE_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
source "$SCRIPT_DIR/lib/common.sh"

PROJECT_ENV=""
SECRETS_ENV=""
APPROVAL_FILE=""
APPLY=0
while [ "$#" -gt 0 ]; do
  case "$1" in
    --project-env) PROJECT_ENV="$2"; shift 2 ;;
    --secrets-env) SECRETS_ENV="$2"; shift 2 ;;
    --approval-file) APPROVAL_FILE="$2"; shift 2 ;;
    --apply) APPLY=1; shift ;;
    *) die "unknown argument: $1" ;;
  esac
done

[ -n "$PROJECT_ENV" ] || die "--project-env is required"
[ -n "$SECRETS_ENV" ] || die "--secrets-env is required"
load_env_file "$PROJECT_ENV"
assert_no_placeholders "$PROJECT_ENV"
require_secret_permissions "$SECRETS_ENV"
assert_no_placeholders "$SECRETS_ENV"
case "$REDIS_CONF_PATH" in
  /etc/redis.conf|/etc/redis/redis.conf) ;;
  *) die "unsupported REDIS_CONF_PATH" ;;
esac

log "PLAN initialize Redis on loopback with password, AOF and bounded memory"
log "PLAN no public listener and no plaintext password output"

[ "$APPLY" -eq 1 ] || {
  log "SHADOW_ONLY: Redis configuration unchanged"
  exit 0
}

[ "$(id -u)" -eq 0 ] || die "Redis configuration requires root"
[ -n "$APPROVAL_FILE" ] || die "--approval-file is required with --apply"
require_apply_authorization "configure-redis" "$APPROVAL_FILE" "$TARGET_HOST_REF"
load_env_file "$SECRETS_ENV"
require_file "$REDIS_CONF_PATH"
require_cmd python3
require_cmd redis-cli

BACKUP_DIR="$BACKUP_ROOT/redis-config-$(date '+%Y%m%dT%H%M%S%z')"
BACKUP_FILE="$BACKUP_DIR/redis.conf.before"
python3 "$PACKAGE_ROOT/tools/configure_redis.py" \
  --config "$REDIS_CONF_PATH" \
  --project-env "$PROJECT_ENV" \
  --secrets-env "$SECRETS_ENV" \
  --backup "$BACKUP_FILE"
if getent group redis >/dev/null; then
  chown root:redis "$REDIS_CONF_PATH"
fi
chmod 640 "$REDIS_CONF_PATH"

restart_redis() {
  if systemctl list-unit-files redis.service >/dev/null 2>&1; then
    systemctl enable --now redis
    systemctl restart redis
  elif systemctl list-unit-files redis5.service >/dev/null 2>&1; then
    systemctl enable --now redis5
    systemctl restart redis5
  elif [ -x /etc/init.d/redis ]; then
    /etc/init.d/redis restart
  else
    return 1
  fi
}

set +e
restart_redis
restart_rc=$?
ping_result=""
if [ "$restart_rc" -eq 0 ]; then
  ping_result="$(
    REDISCLI_AUTH="$REDIS_PASSWORD" redis-cli \
      -h "$REDIS_BIND" -p "$REDIS_PORT" --no-auth-warning ping 2>/dev/null
  )"
fi
set -e
if [ "$restart_rc" -ne 0 ] || [ "$ping_result" != "PONG" ]; then
  cp -p "$BACKUP_FILE" "$REDIS_CONF_PATH"
  restart_redis || true
  die "Redis configuration validation failed; previous file restored"
fi

log "REDIS_CONFIG_APPLIED bind=$REDIS_BIND port=$REDIS_PORT backup=$BACKUP_DIR"