import webview from '@ohos.web.webview'; 
import { TencentQianWebViewConfig } from '../model/TencentQianWebViewConfig'; 
import { OnSdkEvent } from '../model/SignCallback'; 
import { UserAgentInjectFailedEvent } from '../model/SdkEvent'; 
import { TencentQianWebView } from '../TencentQianWebView'; 
 
/** 
 * UA 注入器。 
 * 
 * 在 controller 绑定 Web 组件之后（`onControllerAttached` 时机）， 
 * 将 SDK UA 标识 `qianwv/<version>` 与客户附加段拼接到默认 UA 之后。 
 * 注入失败时通过 `UserAgentInjectFailed` 事件回报，不抛异常、不影响主流程。 
 */ 
export class UserAgentInjector { 
  /** 
   * 注入 UA。 
   * 
   * @param controller 已 attach 的 WebviewController 
   * @param config 客户配置 
   * @param onEvent 可选的事件回调(注入失败时上报) 
   */ 
  public static inject( 
    controller: webview.WebviewController, 
    config: TencentQianWebViewConfig, 
    onEvent?: OnSdkEvent 
  ): void { 
    if (!config.injectUserAgent) { 
      return; 
    } 
    try { 
      const defaultUa: string = controller.getUserAgent(); 
      let combined: string = defaultUa + ' ' + 'qianwv/' + TencentQianWebView.sdkVersion(); 
      const extra: string = config.userAgentExtra; 
      if (extra !== null && extra !== undefined && extra.length > 0) { 
        combined = combined + ' ' + extra; 
      } 
      controller.setCustomUserAgent(combined); 
    } catch (e) { 
      const reason: string = (e instanceof Error) ? e.message : String(e); 
      if (onEvent !== undefined) { 
        onEvent(new UserAgentInjectFailedEvent(reason)); 
      } 
    } 
  } 
 
  // ArkTS 类禁止实例化 
  private constructor() {} 
}