import { type Order, type OrderAction, type OrderBasketItem } from '@openmrs/esm-patient-common-lib';
import { type ObservationValue } from '../../types/encounter';

/**
 * Enables a comparison of arbitrary values with support for undefined/null.
 * Requires the `<` and `>` operators to return something reasonable for the provided values.
 */
export function compare<T>(x?: T, y?: T) {
  if (x == undefined && y == undefined) {
    return 0;
  } else if (x == undefined) {
    return -1;
  } else if (y == undefined) {
    return 1;
  } else if (x < y) {
    return -1;
  } else if (x > y) {
    return 1;
  } else {
    return 0;
  }
}

/**
 * Builds medication order object from the given order object
 */
export function buildMedicationOrder(order: Order, action?: OrderAction) {
  return {
    display: order.drug?.display,
    previousOrder: action !== 'NEW' ? order.uuid : null,
    action: action,
    drug: order.drug,
    dosage: order.dose,
    unit: {
      value: order.doseUnits?.display,
      valueCoded: order.doseUnits?.uuid,
    },
    frequency: {
      valueCoded: order.frequency?.uuid,
      value: order.frequency?.display,
    },
    route: {
      valueCoded: order.route?.uuid,
      value: order.route?.display,
    },
    commonMedicationName: order.drug?.display,
    isFreeTextDosage: order.dosingType === 'org.openmrs.FreeTextDosingInstructions',
    freeTextDosage: order.dosingType === 'org.openmrs.FreeTextDosingInstructions' ? order.dosingInstructions : '',
    patientInstructions: order.dosingType !== 'org.openmrs.FreeTextDosingInstructions' ? order.dosingInstructions : '',
    asNeeded: order.asNeeded,
    asNeededCondition: order.asNeededCondition,
    startDate: action === 'DISCONTINUE' ? order.dateActivated : new Date(),
    duration: order.duration,
    durationUnit: {
      valueCoded: order.durationUnits?.uuid,
      value: order.durationUnits?.display,
    },
    pillsDispensed: order.quantity,
    numRefills: order.numRefills,
    indication: order.orderReasonNonCoded,
    orderer: order.orderer.uuid,
    careSetting: order.careSetting.uuid,
    quantityUnits: {
      value: order.quantityUnits?.display,
      valueCoded: order.quantityUnits?.uuid,
    },
  };
}

/**
 * Builds lab order object from the given order object
 */
export function buildLabOrder(order: Order, action?: OrderAction) {
  return {
    action: action,
    display: order.display,
    previousOrder: action !== 'NEW' ? order.uuid : null,
    orderer: order.orderer.uuid,
    careSetting: order.careSetting.uuid,
    instructions: order.instructions,
    urgency: order.urgency,
    accessionNumber: order.accessionNumber,
    testType: {
      label: order.concept.display,
      conceptUuid: order.concept.uuid,
    },
    orderNumber: order.orderNumber,
    concept: order.concept,
    orderType: order.orderType.uuid,
    specimenSource: null,
    scheduledDate: order.scheduledDate ? new Date(order.scheduledDate) : null,
  };
}

/**
 * Builds general order object from the given order object
 */
export function buildGeneralOrder(order: Order, action?: OrderAction): OrderBasketItem {
  return {
    action: action,
    display: order.display,
    previousOrder: action !== 'NEW' ? order.uuid : null,
    orderer: order.orderer.uuid,
    careSetting: order.careSetting.uuid,
    instructions: order.instructions,
    urgency: order.urgency,
    accessionNumber: order.accessionNumber,
    concept: order.concept,
    orderNumber: order.orderNumber,
    orderType: order.orderType.uuid,
    scheduledDate: order.scheduledDate ? new Date(order.scheduledDate) : null,
  };
}

/**
 * Utility function to extract display value from ObservationValue
 */
export const getObservationDisplayValue = (value: ObservationValue): string => {
  if (!value) {
    return '--';
  }
  if (typeof value === 'string') {
    return value;
  }
  if (typeof value === 'number') {
    return value.toString();
  }
  if (value && typeof value === 'object' && 'display' in value) {
    return value.display;
  }
  return '--';
};

/**
 * Removes the '+' prefix from a phone number if present
 * @param phoneNumber - The phone number to sanitize
 * @returns The phone number without the '+' prefix
 */
export function sanitizePhoneNumber(phoneNumber: string): string {
  if (!phoneNumber) {
    return phoneNumber;
  }
  return phoneNumber.startsWith('+') ? phoneNumber.substring(1) : phoneNumber;
}

/**
 * Masks a phone number by replacing all digits except the first two and the last two with asterisks (*)
 * @example
 * maskPhoneNumber('254712345678') // returns '25471******78'
 * @param phoneNumber - The phone number to be masked
 * @returns The masked phone number
 */
export const maskPhoneNumber = (phoneNumber: string): string => {
  const digits = phoneNumber.replace(/\D/g, '');

  if (digits.length < 8) {
    return phoneNumber;
  }

  const firstPart = digits.slice(0, -6);
  const maskedPart = '*'.repeat(4);
  const lastPart = digits.slice(-2);

  return `${firstPart}${maskedPart}${lastPart}`;
};