/**
 * Monitor Bridge Client
 *
 * Queries the local HarborForge.Monitor bridge endpoint on MONITOR_PORT
 * to enrich plugin telemetry with host/hardware data.
 *
 * If the bridge is unreachable, all methods return null gracefully —
 * the plugin continues to function without Monitor data.
 */

export interface MonitorHealth {
  status: string;
  monitor_version: string;
  identifier: string;
}

export interface MonitorTelemetryResponse {
  status: string;
  monitor_version: string;
  identifier: string;
  telemetry?: {
    identifier: string;
    plugin_version: string;
    cpu_pct: number;
    mem_pct: number;
    disk_pct: number;
    swap_pct: number;
    load_avg: number[];
    uptime_seconds: number;
    nginx_installed: boolean;
    nginx_sites: string[];
  };
  last_updated?: string;
}

export class MonitorBridgeClient {
  private baseUrl: string;
  private timeoutMs: number;

  constructor(port: number, timeoutMs = 3000) {
    this.baseUrl = `http://127.0.0.1:${port}`;
    this.timeoutMs = timeoutMs;
  }

  async health(): Promise<MonitorHealth | null> {
    return this.fetchJson<MonitorHealth>('/health');
  }

  async telemetry(): Promise<MonitorTelemetryResponse | null> {
    return this.fetchJson<MonitorTelemetryResponse>('/telemetry');
  }

  private async fetchJson<T>(path: string): Promise<T | null> {
    try {
      const controller = new AbortController();
      const timeout = setTimeout(() => controller.abort(), this.timeoutMs);

      const response = await fetch(`${this.baseUrl}${path}`, {
        signal: controller.signal,
      });
      clearTimeout(timeout);

      if (!response.ok) return null;
      return (await response.json()) as T;
    } catch {
      return null;
    }
  }
}