import { Inject, InjectionToken, ModuleWithProviders, NgModule, Optional } from "@angular/core";
import { ScanditSdkBarcodePickerComponent } from "./scandit-sdk-barcode-picker.component";
import { ScanditSdkServiceConfig } from "./scandit-sdk.service";

/**
 * Scandit Web SDK Module
 */
@NgModule({
  declarations: [ScanditSdkBarcodePickerComponent],
  exports: [ScanditSdkBarcodePickerComponent]
})
export class ScanditSdkModule {
  static loaded: boolean = false;

  constructor(@Inject("ScanditSdkModuleInstance") instance: ScanditSdkModule) { }

  static factory(): void {
    if (ScanditSdkModule.loaded) {
      throw new Error("ScanditSdkModule is already loaded. Import it in the AppModule only");
    }
    ScanditSdkModule.loaded = true;
  }

  static forRoot(
    licenseKey: string,
    options: { engineLocation: string; preloadEngine?: boolean; preloadBlurryRecognition?: boolean }
  ): ModuleWithProviders<ScanditSdkModule> {
    return {
      ngModule: ScanditSdkModule,
      providers: [
        {
          provide: "ScanditSdkModuleInstance",
          useFactory: ScanditSdkModule.factory
        },
        {
          provide: ScanditSdkServiceConfig,
          useValue: {
            licenseKey,
            options
          }
        }
      ]
    };
  }

  static forChild(): ModuleWithProviders<ScanditSdkModule> {
    return {
      ngModule: ScanditSdkModule,
      providers: []
    };
  }
}