import type { MedipostOrderResponse, MedipostAnalysisResult } from '@/packages/shared/src/types/medipost-analysis';

interface ParsedMessageData {
  analysisResult: NonNullable<MedipostAnalysisResult>;
  orderNumber: string;
  medipostExternalOrderId: number;
  medipostExternalOrderIdRaw: string | number;
  patientPersonalCode: string;
}

type ParseMessageResult =
  | {
      success: true;
      data: ParsedMessageData;
    }
  | {
      success: false;
      reason: 'no_analysis_result' | 'invalid_order_id' | 'invalid_patient_code';
      medipostExternalOrderIdRaw?: string | number;
      medipostExternalOrderId?: number;
    };

export default class MedipostMessageParser {
  public extractAnalysisResult(
    message: MedipostOrderResponse,
  ): ParsedMessageData['analysisResult'] | null {
    return message?.Saadetis?.Vastus ?? null;
  }

  public extractOrderId(
    message: MedipostOrderResponse,
    analysisResult: ParsedMessageData['analysisResult'],
  ): { orderId: number; rawOrderId: string | number } | null {
    const rawOrderId =
      message.Saadetis?.Tellimus?.ValisTellimuseId ||
      analysisResult.ValisTellimuseId;

    if (!rawOrderId) {
      return null;
    }

    const orderId = Number(rawOrderId);
    if (isNaN(orderId)) {
      return null;
    }

    return { orderId, rawOrderId };
  }

  public extractOrderNumber(
    analysisResult: ParsedMessageData['analysisResult'],
  ): string {
    return analysisResult.TellimuseNumber;
  }

  public extractPatientPersonalCode(
    analysisResult: ParsedMessageData['analysisResult'],
  ): string | null {
    return analysisResult.Patsient.Isikukood?.toString() ?? null;
  }

  public parseMessage(message: MedipostOrderResponse): ParseMessageResult {
    const analysisResult = this.extractAnalysisResult(message);
    
    if (!analysisResult) {
      return {
        success: false,
        reason: 'no_analysis_result',
      };
    }

    const orderIdResult = this.extractOrderId(message, analysisResult);
    if (!orderIdResult) {
      return {
        success: false,
        reason: 'invalid_order_id',
        medipostExternalOrderIdRaw: 
          message.Saadetis?.Tellimus?.ValisTellimuseId ||
          analysisResult.ValisTellimuseId,
      };
    }

    const patientPersonalCode = this.extractPatientPersonalCode(analysisResult);
    if (!patientPersonalCode) {
      return {
        success: false,
        reason: 'invalid_patient_code',
        medipostExternalOrderIdRaw: orderIdResult.rawOrderId,
        medipostExternalOrderId: orderIdResult.orderId,
      };
    }

    const orderNumber = this.extractOrderNumber(analysisResult);

    return {
      success: true,
      data: {
        analysisResult,
        orderNumber,
        medipostExternalOrderId: orderIdResult.orderId,
        medipostExternalOrderIdRaw: orderIdResult.rawOrderId,
        patientPersonalCode,
      },
    };
  }
}