import React, { useState, useEffect } from 'react';
import { TextareaControl } from "../ui/textarea-control";
import { Card, CardHeader, CardBody, CardDivider } from '../ui/wp-card';
import { Elevation } from '../ui/elevation';
import { InputControl } from '../ui/input-control';
import { DismissibleAlert } from '../ui/dismissible-alert';
import { Heading } from '../ui/heading';
import { Flex, FlexItem } from '../ui/flex';
import { Spacer } from '../ui/spacer';
import { TabPanel } from '../ui/tab-panel';
import { Disabled } from '../ui/disabled';
import { useFormContext, Controller, useFieldArray } from 'react-hook-form';
import {
    IValueSet,
    useAuthServiceContext,
    useValueSetServiceContext
} from '../../services';
import {
    FhirAnnotation,
    FhirCode,
    FhirCodeableConcept,
    FhirPeriod,
    FhirQuantity,
    FhirRatio,
    FhirReference,
    FhirReferenceCollection,
    FhirValueSetSearch,
    TypeSelector
} from '../../components';
import {
    useFhirConditions,
    useFhirDevices,
    useFhirEncounters,
    useFhirEpisodesOfCare,
    useFhirMedicationAdministrationBroadcast,
    useFhirMedicationAdministrations,
    useFhirMedicationRequests,
    useFhirObservations, useFhirPractitioners,
    useFhirProcedures,
    useFhirRelatedPersons
} from '../../hooks';
import { FhirResource } from 'fhir/r4';
import { PlusCircle, Trash2 } from 'lucide-react';

interface FhirMedicationAdministrationProps {
    elevated?: boolean;
    disabled?: boolean;
    enableInlineActions?: boolean;
}

const PerformerActorReferences: React.FC<{ index: number; disabled: boolean; readonly: boolean; enableInlineActions: boolean; }> = ({ index, disabled, readonly = false, enableInlineActions = true }) => {
    const { control } = useFormContext();
    const itemReferenceFieldArray = useFieldArray({ control, name: `performer.${index}.actor` });

    const { practitionersList } = useFhirPractitioners();
    const { devicesList } = useFhirDevices();
    const { relatedPersonsList } = useFhirRelatedPersons();

    return (
        <FhirReferenceCollection label="Who performed the medication administration"
                                 references={itemReferenceFieldArray}
                                 context={`performer.${index}.actor`}
                                 referenceTypes={[
                                     { name: 'Practitioner', key: 'Practitioner' },
                                     { name: 'Patient', key: 'Patient' },
                                     { name: 'RelatedPerson', key: 'RelatedPerson' },
                                     { name: 'Device', key: 'Device' }
                                 ]}
                                 getReferenceList={(referenceType: string): FhirResource[] => {
                                     switch (referenceType) {
                                         case 'Practitioner':
                                             return practitionersList.map(p => p.practitioner);
                                         case 'RelatedPerson':
                                             return relatedPersonsList;
                                         case 'Device':
                                             return devicesList;
                                         default:
                                             return [];
                                     }
                                 }}
                                 required={true}
                                 disabled={disabled}
                                 readonly={readonly}
                                 multiple={false}
                                 enableInlineActions={enableInlineActions}/>
    );
};

export const FhirMedicationAdministration: React.FC<FhirMedicationAdministrationProps> = ({ elevated = true, disabled = false, enableInlineActions = true }) => {
    const { control, watch } = useFormContext();
    const { userRole, USER_ROLES } = useAuthServiceContext();
    const { fetchValueSet, valueSetUrls } = useValueSetServiceContext();

    const [loading, setLoading] = useState(false);

    // value sets
    const [medicationAdminStatus, setMedicationAdminStatus] = useState<IValueSet[]>([]);
    const [reasonMedicationNotGivenCodes, setReasonMedicationNotGivenCodes] = useState<IValueSet[]>([]);
    const [medicationAdminCategory, setMedicationAdminCategory] = useState<IValueSet[]>([]);
    const [medAdminPerformFunction, setMedAdminPerformFunction] = useState<IValueSet[]>([]);
    const [reasonMedicationGivenCodes, setReasonMedicationGivenCodes] = useState<IValueSet[]>([]);
    const [administrationMethodCodes, setAdministrationMethodCodes] = useState<IValueSet[]>([]);

    const isPatient = [USER_ROLES.PATIENT, USER_ROLES.RELATED_PERSON].includes(userRole as string);
    const spacerMargin = '24px';

    useFhirMedicationAdministrationBroadcast();
    const { medicationAdministrationsList } = useFhirMedicationAdministrations();
    const { encountersList } = useFhirEncounters();
    const { episodesOfCareList } = useFhirEpisodesOfCare();
    const { conditionsList } = useFhirConditions();
    const { devicesList } = useFhirDevices();
    const { proceduresList } = useFhirProcedures();
    const { observationsList } = useFhirObservations();
    const { medicationRequestsList } = useFhirMedicationRequests();

    const medicationType = watch('medicationType');
    const effectiveType = watch('effectiveType');
    const rateType = watch('dosage.rateType');

    const contextFieldArray = useFieldArray({ control, name: 'context' });
    const reasonReferenceFieldArray = useFieldArray({ control, name: 'reasonReference' });
    const performerFieldArray = useFieldArray({ control, name: 'performer' });
    const partOfFieldArray = useFieldArray({ control, name: 'partOf' });

    useEffect(() => {
        const loadValueSets = async () => {
            setLoading(true);
            try {
                const [
                    medicationAdminStatusValueSet,
                    reasonMedicationNotGivenCodesValueSet,
                    medicationAdminCategoryValueSet,
                    medAdminPerformFunctionValueSet,
                    reasonMedicationGivenCodesValueSet,
                    administrationMethodCodesValueSet
                ] = await Promise.all([
                    fetchValueSet(valueSetUrls.medicationAdminStatus),
                    fetchValueSet(valueSetUrls.reasonMedicationNotGivenCodes),
                    fetchValueSet(valueSetUrls.medicationAdminCategory),
                    fetchValueSet(valueSetUrls.medAdminPerformFunction),
                    fetchValueSet(valueSetUrls.reasonMedicationGivenCodes),
                    fetchValueSet(valueSetUrls.administrationMethodCodes)
                ]);

                setMedicationAdminStatus(medicationAdminStatusValueSet);
                setReasonMedicationNotGivenCodes(reasonMedicationNotGivenCodesValueSet);
                setMedicationAdminCategory(medicationAdminCategoryValueSet);
                setMedAdminPerformFunction(medAdminPerformFunctionValueSet);
                setReasonMedicationGivenCodes(reasonMedicationGivenCodesValueSet);
                setAdministrationMethodCodes(administrationMethodCodesValueSet);
            } catch (err) {
                console.error('Error loading value sets:', err);
            } finally {
                setLoading(false);
            }
        };

        loadValueSets();
    }, [fetchValueSet, valueSetUrls]);

    const addPerformer = () => {
        performerFieldArray.append({
            function: null,
            actor: null
        });
    };

    const removePerformer = (index: number) => {
        performerFieldArray.remove(index);
    };

    return (
        <Card style={elevated ? { boxShadow: 'none' } : {}}>
            {elevated && <Elevation value={5}/>}
            <CardHeader>
                <Heading level={5}>Details</Heading>
            </CardHeader>
            <Disabled isDisabled={isPatient}>
                <CardBody>
                    {/* medicationCodeableConcept */}
                    <FhirValueSetSearch label="What was administered"
                                        context="medicationCodeableConcept"
                                        valueSetUrl={valueSetUrls.medicationCodes}
                                        placeholder="Search for medications..."
                                        required={true}
                                        multiple={false}
                                        disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {medicationType === 'codeableConcept' && (
                        <>

                        </>
                    )}

                    {medicationType === 'reference' && (
                        <>
                            {/* medicationReference */}
                        </>
                    )}

                    {/* status */}
                    <FhirCode label="Status"
                              context="status"
                              options={medicationAdminStatus}
                              required={true}
                              loading={loading}
                              disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* statusReason */}
                    <FhirCodeableConcept label={`Reason administration not performed`}
                                         context={`statusReason`}
                                         options={reasonMedicationNotGivenCodes}
                                         multiple={true}
                                         loading={loading}
                                         disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* category */}
                    <FhirCodeableConcept label="Type of medication usage"
                                         context="category"
                                         options={medicationAdminCategory}
                                         loading={loading}
                                         disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* effectiveType */}
                    <TypeSelector label="Start and end time of administration"
                                  context="effectiveType"
                                  options={[
                                      { name: 'Date', key: 'dateTime' },
                                      { name: 'Period', key: 'period' }
                                  ]}
                                  required={true}
                                  disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {effectiveType === 'dateTime' && (
                        <>
                            {/* effectiveDateTime */}
                            <Controller key="effectiveDateTime"
                                        name="effectiveDateTime"
                                        control={control}
                                        disabled={disabled}
                                        rules={{ required: true }}
                                        render={({ field, fieldState }) => (
                                            <>
                                                <InputControl
                                                              {...field}
                                                              label="Effective Date *"
                                                              type="datetime-local"/>

                                                {fieldState.error && (
                                                    <DismissibleAlert status="error">
                                                        Date is required
                                                    </DismissibleAlert>
                                                )}
                                            </>
                                        )}/>

                            <Spacer margin={spacerMargin}/>
                        </>
                    )}

                    {effectiveType === 'period' && (
                        <>
                            {/* effectivePeriod */}
                            <FhirPeriod label="Effective Period"
                                        context="effectivePeriod"
                                        disabled={disabled}
                                        readonly={isPatient}/>

                            <Spacer margin={spacerMargin}/>
                        </>
                    )}

                    {/* request */}
                    <FhirReference label="Request administration performed against"
                                   context="request"
                                   referenceType="MedicationRequest"
                                   referenceList={medicationRequestsList}
                                   enableInlineActions={enableInlineActions}
                                   required={false}
                                   disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* device */}
                    <FhirReference label="Device used to administer"
                                   context="device"
                                   referenceType="Device"
                                   referenceList={devicesList}
                                   enableInlineActions={enableInlineActions}
                                   multiple={true}
                                   required={false}
                                   disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* context */}
                    <FhirReferenceCollection label="Encounter or Episode of Care administered as part of"
                                             references={contextFieldArray}
                                             context="context"
                                             referenceTypes={[
                                                 { name: 'Encounter', key: 'Encounter' },
                                                 { name: 'EpisodeOfCare', key: 'EpisodeOfCare' }
                                             ]}
                                             getReferenceList={(referenceType: string): FhirResource[] => {
                                                 switch (referenceType) {
                                                     case 'Encounter':
                                                         return encountersList;
                                                     case 'EpisodeOfCare':
                                                         return episodesOfCareList;
                                                     default:
                                                         return [];
                                                 }
                                             }}
                                             required={false}
                                             disabled={disabled}
                                             readonly={isPatient}
                                             multiple={false}
                                             enableInlineActions={enableInlineActions}/>

                    <Spacer margin={spacerMargin}/>
                </CardBody>
            </Disabled>
            <CardDivider/>
            <CardBody>
                <TabPanel initialTabName="dosage"
                          tabs={[
                              { name: 'dosage', title: 'Dosage' },
                              { name: 'reasons', title: 'Reasons' },
                              { name: 'performers', title: 'Performers' },
                              { name: 'partOf', title: 'Part Of' },
                              { name: 'notes', title: 'Notes' }
                          ]}>
                    {(tab) => {
                        // dosage
                        if (tab.name === 'dosage') {
                            return (
                                <Disabled isDisabled={isPatient}>
                                    <div style={{ paddingTop: '16px' }}>
                                        <Spacer margin={spacerMargin}/>

                                        {/* dosage.rateType */}
                                        <TypeSelector label="Dose quantity per unit of time"
                                                      context="dosage.rateType"
                                                      options={[
                                                          { name: 'Ratio', key: 'ratio' },
                                                          { name: 'Quantity', key: 'quantity' }
                                                      ]}
                                                      disabled={disabled}/>

                                        <Spacer margin={spacerMargin}/>

                                        {rateType === 'ratio' && (
                                            <>
                                                {/* dosage.rateRatio */}
                                                <FhirRatio label="Rate Ratio"
                                                           context="dosage.rateRatio"
                                                           disabled={disabled}/>

                                                <Spacer margin={spacerMargin}/>
                                            </>
                                        )}

                                        {rateType === 'quantity' && (
                                            <>
                                                {/* dosage.rateQuantity */}
                                                <FhirQuantity label="Rate Quantity"
                                                              context="dosage.rateQuantity"
                                                              isSimpleQuantity={true}
                                                              disabled={disabled}/>

                                                <Spacer margin={spacerMargin}/>
                                            </>
                                        )}

                                        {/* dosage.text */}
                                        <Controller name="dosage.text"
                                                    control={control}
                                                    disabled={disabled}
                                                    render={({ field }) => (
                                                        <TextareaControl
                                                                         label="Dosage Instructions"
                                                                         value={field.value}
                                                                         onChange={field.onChange}
                                                                         placeholder="Free text dosage instructions"
                                                                         rows={3}/>
                                                    )}/>

                                        <Spacer margin={spacerMargin}/>

                                        {/* dosage.site */}
                                        <FhirValueSetSearch label="Body site administered to"
                                                            context="dosage.site"
                                                            valueSetUrl={valueSetUrls.approachSiteCodes}
                                                            placeholder="Search for administration sites..."
                                                            multiple={false}
                                                            disabled={disabled}/>

                                        <Spacer margin={spacerMargin}/>

                                        {/* dosage.route */}
                                        <FhirValueSetSearch label="Path of substance into body"
                                                            context="dosage.route"
                                                            valueSetUrl={valueSetUrls.routeCodes}
                                                            placeholder="Search for administration routes..."
                                                            multiple={false}
                                                            disabled={disabled}/>

                                        <Spacer margin={spacerMargin}/>

                                        {/* dosage.method */}
                                        <FhirCodeableConcept label="Method"
                                                             context="dosage.method"
                                                             options={administrationMethodCodes}
                                                             loading={loading}
                                                             disabled={disabled}/>

                                        <Spacer margin={spacerMargin}/>

                                        {/* dosage.dose */}
                                        <FhirQuantity label="Dose"
                                                      context="dosage.dose"
                                                      isSimpleQuantity={true}
                                                      disabled={disabled}/>

                                        <Spacer margin={spacerMargin}/>
                                    </div>
                                </Disabled>
                            );
                        }

                        // reasons
                        if (tab.name === 'reasons') {
                            return (
                                <Disabled isDisabled={isPatient}>
                                    <div style={{ paddingTop: '16px' }}>
                                        <Spacer margin={spacerMargin}/>

                                        {/* reasonMedicationGivenCodes */}
                                        <FhirCodeableConcept label={`Reason administration performed`}
                                                             context={`reasonCode`}
                                                             options={reasonMedicationGivenCodes}
                                                             multiple={true}
                                                             loading={loading}
                                                             disabled={disabled}/>

                                        <Spacer margin={spacerMargin}/>

                                        {/* reasonReference */}
                                        <FhirReferenceCollection label="Condition or observation that supports why the medication was administered"
                                                                 references={reasonReferenceFieldArray}
                                                                 context="reasonReference"
                                                                 referenceTypes={[
                                                                     { name: 'Condition', key: 'Condition' },
                                                                     { name: 'Observation', key: 'Observation' }
                                                                 ]}
                                                                 getReferenceList={(referenceType: string): FhirResource[] => {
                                                                     switch (referenceType) {
                                                                         case 'Condition':
                                                                             return conditionsList;
                                                                         case 'Observation':
                                                                             return observationsList;
                                                                         default:
                                                                             return [];
                                                                     }
                                                                 }}
                                                                 required={false}
                                                                 multiple={true}
                                                                 disabled={disabled}
                                                                 readonly={isPatient}
                                                                 enableInlineActions={enableInlineActions}/>

                                        <Spacer margin={spacerMargin}/>
                                    </div>
                                </Disabled>
                            );
                        }

                        // performers
                        if (tab.name === 'performers') {
                            return (
                                <Disabled isDisabled={isPatient}>
                                    <div style={{ paddingTop: '16px' }}>
                                        {performerFieldArray.fields.length === 0 && (
                                            <>
                                                <Flex>
                                                    <FlexItem>
                                                        {!isPatient && (
                                                            <button
                                                                type="button"
                                                                className={`btn btn-blue-ghost${disabled ? ' btn-busy' : ''}`}
                                                                onClick={addPerformer}
                                                                disabled={disabled}
                                                            >
                                                                <PlusCircle />
                                                                Add Performer
                                                            </button>
                                                        )}
                                                    </FlexItem>
                                                </Flex>
                                                <Spacer margin="8"/>

                                                <DismissibleAlert status="info">
                                                    No performers added yet.
                                                </DismissibleAlert>

                                                <Spacer margin={spacerMargin}/>
                                            </>
                                        )}

                                        {performerFieldArray.fields.map((field, index) => (
                                            <React.Fragment key={field.id}>
                                                <Card>
                                                    <CardHeader>
                                                        <Flex align="center" justify="space-between">
                                                            <FlexItem>
                                                                <h4>Performer {index + 1}</h4>
                                                            </FlexItem>
                                                            <FlexItem>
                                                                {!isPatient && (
                                                                    <button
                                                                        type="button"
                                                                        className="btn btn-red-ghost"
                                                                        title="Remove performer"
                                                                        aria-label="Remove performer"
                                                                        onClick={() => removePerformer(index)}
                                                                        disabled={disabled}
                                                                    >
                                                                        <Trash2 />
                                                                    </button>
                                                                )}
                                                            </FlexItem>
                                                        </Flex>
                                                    </CardHeader>
                                                    <CardBody>
                                                        <Spacer margin={spacerMargin}/>

                                                        {/* performerType */}
                                                        <FhirCodeableConcept label={`Type of performance`}
                                                                             context={`performer.${index}.function`}
                                                                             options={medAdminPerformFunction}
                                                                             multiple={false}
                                                                             loading={loading}
                                                                             disabled={disabled}/>

                                                        <Spacer margin={spacerMargin}/>

                                                        {/* performer */}
                                                        <PerformerActorReferences index={index}
                                                                                  disabled={disabled}
                                                                                  readonly={isPatient}
                                                                                  enableInlineActions={enableInlineActions}/>

                                                        <Spacer margin={spacerMargin}/>
                                                    </CardBody>
                                                </Card>
                                                <Spacer margin={spacerMargin} />
                                            </React.Fragment>
                                        ))}

                                        {!isPatient && performerFieldArray.fields.length > 0 && (
                                            <Flex justify="center">
                                                <FlexItem>
                                                    <button
                                                        type="button"
                                                        className={`btn btn-blue-ghost${disabled ? ' btn-busy' : ''}`}
                                                        onClick={addPerformer}
                                                        disabled={disabled}
                                                    >
                                                        <PlusCircle />
                                                        Add Performer
                                                    </button>
                                                </FlexItem>
                                            </Flex>
                                        )}
                                    </div>
                                </Disabled>
                            );
                        }

                        // partOf
                        if (tab.name === 'partOf') {
                            return (
                                <Disabled isDisabled={isPatient}>
                                    <div style={{ paddingTop: '16px' }}>
                                        <Spacer margin={spacerMargin}/>

                                        {/* partOf */}
                                        <FhirReferenceCollection label="Part of referenced event"
                                                                 references={partOfFieldArray}
                                                                 context="partOf"
                                                                 referenceTypes={[
                                                                     { name: 'MedicationAdministration', key: 'MedicationAdministration' },
                                                                     { name: 'Procedure', key: 'Procedure' }
                                                                 ]}
                                                                 getReferenceList={(referenceType: string): FhirResource[] => {
                                                                     switch (referenceType) {
                                                                         case 'MedicationAdministration':
                                                                             return medicationAdministrationsList;
                                                                         case 'Procedure':
                                                                             return proceduresList;
                                                                         default:
                                                                             return [];
                                                                     }
                                                                 }}
                                                                 required={false}
                                                                 disabled={disabled}
                                                                 readonly={isPatient}
                                                                 enableInlineActions={enableInlineActions}/>

                                        <Spacer margin={spacerMargin}/>
                                    </div>
                                </Disabled>
                            );
                        }

                        // notes
                        if (tab.name === 'notes') {
                            return (
                                <Disabled isDisabled={isPatient}>
                                    <div style={{ paddingTop: '16px' }}>
                                        <Spacer margin={spacerMargin}/>

                                        {/* note */}
                                        <FhirAnnotation label="Information about the administration"
                                                        context={`note`}
                                                        disabled={disabled}
                                                        readonly={isPatient}/>

                                        <Spacer margin={spacerMargin}/>
                                    </div>
                                </Disabled>
                            );
                        }
                    }}
                </TabPanel>
            </CardBody>
        </Card>
    );
};

export default FhirMedicationAdministration;