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

OPENCLAW_ENTRYPOINT_TAG="upgrade-openclaw"

timestamp_utc() {
  date -u +"%Y-%m-%dT%H:%M:%SZ"
}

log_info() {
  printf '[%s] [INFO] [%s] %s\n' "$(timestamp_utc)" "$OPENCLAW_ENTRYPOINT_TAG" "$*"
}

log_warn() {
  printf '[%s] [WARN] [%s] %s\n' "$(timestamp_utc)" "$OPENCLAW_ENTRYPOINT_TAG" "$*" >&2
}

log_error() {
  printf '[%s] [ERROR] [%s] %s\n' "$(timestamp_utc)" "$OPENCLAW_ENTRYPOINT_TAG" "$*" >&2
}

is_true() {
  local value
  value="$(printf '%s' "${1:-}" | tr '[:upper:]' '[:lower:]')"
  [[ "$value" == "1" || "$value" == "true" || "$value" == "yes" || "$value" == "on" ]]
}

get_current_version() {
  local version
  if command -v openclaw >/dev/null 2>&1; then
    version="$(openclaw --version 2>/dev/null | head -1 | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1)" || version=""
    if [[ -z "$version" ]]; then
      version="$(openclaw --version 2>/dev/null | head -1 | awk '{print $NF}')" || version="unknown"
    fi
  else
    version="not-installed"
  fi
  printf '%s' "$version"
}

resolve_latest_version() {
  local version
  version="$(curl -fsSL https://registry.npmjs.org/openclaw/latest 2>/dev/null | python3 -c "
import json, sys
try:
    data = json.load(sys.stdin)
    print(data.get('version', 'latest'))
except:
    print('latest')
" 2>/dev/null)" || version="latest"
  printf '%s' "$version"
}

backup_openclaw_state() {
  local backup_dir="/root/.openclaw.backup.$(date +%Y%m%d%H%M%S)"
  
  if [[ -d "/root/.openclaw" ]]; then
    log_info "Backing up OpenClaw state to $backup_dir..."
    cp -r /root/.openclaw "$backup_dir"
    log_info "Backup completed: $backup_dir"
  else
    log_warn "No existing OpenClaw state found, skipping backup"
  fi
}

upgrade_openclaw() {
  local target_version="$1"
  local skip_backup="$2"
  
  if ! is_true "$skip_backup"; then
    backup_openclaw_state
  fi
  
  log_info "Upgrading OpenClaw to version: $target_version..."
  
  local install_start
  install_start=$(date +%s)
  
  HOME=/root curl -fsSL https://openclaw.ai/install.sh | bash -s -- --no-onboard --version "$target_version"
  
  local install_end
  install_end=$(date +%s)
  local install_duration=$((install_end - install_start))
  
  log_info "Installation completed in ${install_duration}s"
  
  local new_version
  new_version="$(get_current_version)"
  log_info "OpenClaw upgraded to: $new_version"
  
  if [[ "$new_version" == "unknown" || "$new_version" == "not-installed" ]]; then
    log_error "Upgrade verification failed: openclaw command not found"
    return 1
  fi
  
  if [[ "$target_version" != "latest" && "$new_version" != *"$target_version"* ]]; then
    log_warn "Version mismatch: expected $target_version, got $new_version"
  fi
  
  return 0
}

restart_gateway() {
  log_info "Restarting OpenClaw gateway..."
  
  if command -v openclaw-gateway-ctl >/dev/null 2>&1; then
    if openclaw-gateway-ctl status >/dev/null 2>&1; then
      openclaw-gateway-ctl restart || log_warn "Gateway restart failed, manual restart may be needed"
    else
      log_warn "Gateway is not running, skipping restart"
    fi
  else
    log_warn "openclaw-gateway-ctl not found, skipping gateway restart"
  fi
}

show_usage() {
  cat <<'EOF'
Usage: upgrade-openclaw.sh [OPTIONS] [VERSION]

Upgrade OpenClaw to a specific version or the latest version.

Arguments:
  VERSION              Target version (default: from OPENCLAW_VERSION env var, or "latest")

Options:
  -l, --latest         Upgrade to the latest version
  -v, --version VER    Specify version to upgrade to
  -s, --skip-backup    Skip backup of current state
  -n, --dry-run        Show what would be done without making changes
  -h, --help           Show this help message

Environment Variables:
  OPENCLAW_VERSION     Target version (overridden by command line arguments)

Examples:
  upgrade-openclaw.sh                    # Use OPENCLAW_VERSION or "latest"
  upgrade-openclaw.sh 2026.5.1           # Upgrade to specific version
  upgrade-openclaw.sh --latest           # Upgrade to latest version
  upgrade-openclaw.sh -v 2026.4.15 -s    # Upgrade to version, skip backup
  upgrade-openclaw.sh --dry-run          # Preview upgrade without executing
EOF
}

main() {
  local target_version=""
  local skip_backup="false"
  local dry_run="false"
  local use_latest="false"
  
  while [[ $# -gt 0 ]]; do
    case "$1" in
      -l|--latest)
        use_latest="true"
        shift
        ;;
      -v|--version)
        target_version="$2"
        shift 2
        ;;
      -s|--skip-backup)
        skip_backup="true"
        shift
        ;;
      -n|--dry-run)
        dry_run="true"
        shift
        ;;
      -h|--help)
        show_usage
        exit 0
        ;;
      -*)
        log_error "Unknown option: $1"
        show_usage
        exit 1
        ;;
      *)
        target_version="$1"
        shift
        ;;
    esac
  done
  
  if [[ -z "$target_version" ]]; then
    if is_true "$use_latest"; then
      target_version="latest"
    elif [[ -n "${OPENCLAW_VERSION:-}" ]]; then
      target_version="$OPENCLAW_VERSION"
    else
      target_version="latest"
    fi
  fi
  
  local current_version
  current_version="$(get_current_version)"
  
  log_info "=========================================="
  log_info "OpenClaw Upgrade Tool"
  log_info "=========================================="
  log_info "Current version: $current_version"
  log_info "Target version:  $target_version"
  log_info "Skip backup:     $skip_backup"
  log_info "Dry run:         $dry_run"
  log_info "=========================================="
  
  if [[ "$current_version" == "$target_version" ]] || [[ "$current_version" == *"$target_version"* && "$target_version" != "latest" ]]; then
    log_info "Already at target version, no upgrade needed"
    exit 0
  fi
  
  if is_true "$dry_run"; then
    log_info "[DRY RUN] Would upgrade OpenClaw from $current_version to $target_version"
    if ! is_true "$skip_backup"; then
      log_info "[DRY RUN] Would backup current state to /root/.openclaw.backup.<timestamp>"
    fi
    log_info "[DRY RUN] Would restart gateway after upgrade"
    exit 0
  fi
  
  if [[ "$target_version" == "latest" ]]; then
    local resolved_version
    resolved_version="$(resolve_latest_version)"
    log_info "Resolved 'latest' to: $resolved_version"
    
    if [[ "$current_version" == "$resolved_version" ]] || [[ "$current_version" == *"$resolved_version"* ]]; then
      log_info "Already at latest version ($resolved_version), no upgrade needed"
      exit 0
    fi
    
    target_version="$resolved_version"
  fi
  
  upgrade_openclaw "$target_version" "$skip_backup"
  
  log_info "Upgrade completed successfully"
  log_info "New version: $(get_current_version)"
  
  restart_gateway
  
  log_info "=========================================="
  log_info "Upgrade finished!"
  log_info "=========================================="
}

main "$@"