import React, { useState, useEffect } from 'react';
import { Card, CardHeader, CardBody, CardDivider } from '../ui/wp-card';
import { Elevation } from '../ui/elevation';
import { InputControl } from '../ui/input-control';
import { Divider } from '../ui/divider';
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 {
    FhirCode,
    FhirCodeableConcept,
    FhirPeriod,
    FhirReference
} from '../../components';
import {
    useFhirCareTeams,
    useFhirConditions,
    useFhirEpisodeOfCareBroadcast,
    useFhirEpisodesOfCare,
    useFhirPractitioners
} from '../../hooks';
import { PlusCircle, Trash2 } from 'lucide-react';

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

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

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

    // value sets
    const [episodeOfCareStatus, setEpisodeOfCareStatus] = useState<IValueSet[]>([]);
    const [episodeofcareType, setEpisodeofcareType] = useState<IValueSet[]>([]);
    const [diagnosisRole, setDiagnosisRole] = useState<IValueSet[]>([]);

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

    useFhirEpisodesOfCare();
    useFhirEpisodeOfCareBroadcast();
    const { conditionsList } = useFhirConditions();
    const { careTeamsList } = useFhirCareTeams();
    const { practitionersList } = useFhirPractitioners();

    const statusHistoryFieldArray = useFieldArray({ control, name: 'statusHistory' });
    const diagnosisFieldArray = useFieldArray({ control, name: 'diagnosis' });

    useEffect(() => {
        const loadValueSets = async () => {
            setLoading(true);
            try {
                const [
                    episodeOfCareStatusValueSet,
                    episodeofcareTypeValueSet,
                    diagnosisRoleValueSet,
                ] = await Promise.all([
                    fetchValueSet(valueSetUrls.episodeOfCareStatus),
                    fetchValueSet(valueSetUrls.episodeofcareType),
                    fetchValueSet(valueSetUrls.diagnosisRole)
                ]);

                setEpisodeOfCareStatus(episodeOfCareStatusValueSet);
                setEpisodeofcareType(episodeofcareTypeValueSet);
                setDiagnosisRole(diagnosisRoleValueSet);
            } catch (err) {
                console.error('Error loading value sets:', err);
            } finally {
                setLoading(false);
            }
        };

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

    const addStatusHistory = () => {
        statusHistoryFieldArray.append({
            status: '',
        });
    };

    const removeStatusHistory = (index: number) => {
        statusHistoryFieldArray.remove(index);
    };

    const addDiagnosis = () => {
        diagnosisFieldArray.append({
            condition: null,
            role: null,
            rank: null
        });
    };

    const removeDiagnosis = (index: number) => {
        diagnosisFieldArray.remove(index);
    };

    return (
        <Card style={elevated ? { boxShadow: 'none' } : {}}>
            {elevated && <Elevation value={5}/>}
            <CardHeader>
                <Heading level={5}>Details</Heading>
            </CardHeader>
            <Disabled isDisabled={isPatient}>
                <CardBody>
                    {/* status */}
                    <FhirCode label="Status"
                              context="status"
                              options={episodeOfCareStatus}
                              required={true}
                              loading={loading}
                              disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* type */}
                    <FhirCodeableConcept label="Type/class - e.g. specialist referral, disease management"
                                         context="type"
                                         options={episodeofcareType}
                                         multiple={true}
                                         loading={loading}
                                         disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* period */}
                    <FhirPeriod label="Interval during responsibility is assumed"
                                context="period"
                                disabled={disabled}
                                readonly={isPatient}/>

                    <Spacer margin={spacerMargin}/>

                    {/* careManager */}
                    <FhirReference label="Care manager/care coordinator for the patient"
                                   context="careManager"
                                   referenceType="Practitioner"
                                   referenceList={practitionersList.map(p => p.practitioner)}
                                   enableInlineActions={enableInlineActions}
                                   required={false}
                                   disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>

                    {/* team */}
                    <FhirReference label="Other practitioners facilitating this episode of care"
                                   context="team"
                                   referenceType="CareTeam"
                                   referenceList={careTeamsList}
                                   enableInlineActions={enableInlineActions}
                                   multiple={true}
                                   required={false}
                                   disabled={disabled}/>

                    <Spacer margin={spacerMargin}/>
                </CardBody>
            </Disabled>
            <CardDivider/>
            <CardBody>
                <TabPanel initialTabName="diagnosis"
                          tabs={[
                              { name: 'diagnosis', title: 'Diagnosis' },
                              { name: 'statusHistory', title: 'Status History' }
                          ]}>
                    {(tab) => {
                        // diagnosis
                        if (tab.name === 'diagnosis') {
                            return (
                                <Disabled isDisabled={isPatient}>
                                    <div style={{ paddingTop: '16px' }}>
                                        <Spacer margin={spacerMargin}/>

                                        {diagnosisFieldArray.fields.length === 0 && (
                                            <>
                                                <Flex>
                                                    <FlexItem>
                                                        <Heading level={5}>Diagnoses</Heading>
                                                    </FlexItem>
                                                    <FlexItem>
                                                        {!isPatient && (
                                                            <button type="button"
                                                                    className={`btn btn-blue-ghost${disabled ? ' btn-busy' : ''}`}
                                                                    onClick={addDiagnosis}
                                                                    disabled={disabled}>
                                                                <PlusCircle className="w-4 h-4" />
                                                                Add Diagnosis
                                                            </button>
                                                        )}
                                                    </FlexItem>
                                                </Flex>
                                                <Divider margin="2"/>
                                                <Spacer margin="8"/>
                                                <DismissibleAlert status="info">
                                                    No diagnoses added yet.
                                                </DismissibleAlert>
                                                <Spacer margin={spacerMargin}/>
                                            </>
                                        )}

                                        {diagnosisFieldArray.fields.map((field, index) => (
                                            <React.Fragment key={field.id}>
                                                <Card>
                                                    <CardHeader>
                                                        <Flex align="center" justify="space-between">
                                                            <FlexItem>
                                                                <h4>Diagnosis {index + 1}</h4>
                                                            </FlexItem>
                                                            <FlexItem>
                                                                {!isPatient && (
                                                                    <button type="button"
                                                                            className="btn btn-red-ghost"
                                                                            title="Remove diagnosis"
                                                                            aria-label="Remove diagnosis"
                                                                            onClick={() => removeDiagnosis(index)}
                                                                            disabled={disabled}>
                                                                        <Trash2 className="w-4 h-4" />
                                                                    </button>
                                                                )}
                                                            </FlexItem>
                                                        </Flex>
                                                    </CardHeader>
                                                    <CardBody>
                                                        {/* diagnosis.condition */}
                                                        <FhirReference label="Conditions/problems/diagnoses this episode of care is for"
                                                                       context={`diagnosis.${index}.condition`}
                                                                       referenceType="Condition"
                                                                       referenceList={conditionsList}
                                                                       enableInlineActions={enableInlineActions}
                                                                       required={true}
                                                                       disabled={disabled}/>

                                                        <Spacer margin={spacerMargin}/>

                                                        {/* diagnosis.role */}
                                                        <FhirCodeableConcept label="Role that this diagnosis has within the episode of care (e.g. admission, billing, discharge …)"
                                                                             context={`diagnosis.${index}.role`}
                                                                             options={diagnosisRole}
                                                                             loading={loading}
                                                                             disabled={disabled}/>
                                                        <Spacer margin={spacerMargin}/>

                                                        {/* diagnosis.rank */}
                                                        <Controller key={`diagnosis.${index}.rank`}
                                                                    name={`diagnosis.${index}.rank`}
                                                                    control={control}
                                                                    disabled={disabled}
                                                                    render={({ field }) => (
                                                                        <InputControl
                                                                                      {...field}
                                                                                      label="Ranking of the diagnosis (for each role type)"
                                                                                      type="number"
                                                                                      min="1"/>
                                                                    )}/>
                                                    </CardBody>
                                                </Card>
                                                <Spacer margin={spacerMargin}/>
                                            </React.Fragment>
                                        ))}

                                        {!isPatient && diagnosisFieldArray.fields.length > 0 && (
                                            <Flex justify="center">
                                                <FlexItem>
                                                    <button type="button"
                                                            className={`btn btn-blue-ghost${disabled ? ' btn-busy' : ''}`}
                                                            onClick={addDiagnosis}
                                                            disabled={disabled}>
                                                        <PlusCircle className="w-4 h-4" />
                                                        Add Diagnosis
                                                    </button>
                                                </FlexItem>
                                            </Flex>
                                        )}
                                    </div>
                                </Disabled>
                            );
                        }

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

                                        {statusHistoryFieldArray.fields.length === 0 && (
                                            <>
                                                <Flex>
                                                    <FlexItem>
                                                        <Heading level={5}>Past list of status codes (the current status may be included to cover the start date of the status)</Heading>
                                                    </FlexItem>
                                                    <FlexItem>
                                                        {!isPatient && (
                                                            <button type="button"
                                                                    className={`btn btn-blue-ghost${disabled ? ' btn-busy' : ''}`}
                                                                    onClick={addStatusHistory}
                                                                    disabled={disabled}>
                                                                <PlusCircle className="w-4 h-4" />
                                                                Add Status History
                                                            </button>
                                                        )}
                                                    </FlexItem>
                                                </Flex>
                                                <Divider margin="2"/>
                                                <Spacer margin="8"/>

                                                <DismissibleAlert status="info">
                                                    No status history added yet.
                                                </DismissibleAlert>
                                                <Spacer margin={spacerMargin}/>
                                            </>
                                        )}

                                        {statusHistoryFieldArray.fields.map((field, index) => (
                                            <React.Fragment key={field.id}>
                                                <Card>
                                                    <CardHeader>
                                                        <Flex align="center" justify="space-between">
                                                            <FlexItem>
                                                                <h4>Status History {index + 1}</h4>
                                                            </FlexItem>
                                                            <FlexItem>
                                                                {!isPatient && (
                                                                    <button type="button"
                                                                            className="btn btn-red-ghost"
                                                                            title="Remove status history"
                                                                            aria-label="Remove status history"
                                                                            onClick={() => removeStatusHistory(index)}
                                                                            disabled={disabled}>
                                                                        <Trash2 className="w-4 h-4" />
                                                                    </button>
                                                                )}
                                                            </FlexItem>
                                                        </Flex>
                                                    </CardHeader>
                                                    <CardBody>
                                                        {/* status */}
                                                        <FhirCode label="Status"
                                                                  context={`statusHistory.${index}.status`}
                                                                  options={episodeOfCareStatus}
                                                                  required={true}
                                                                  loading={loading}
                                                                  disabled={disabled}/>
                                                        <Spacer margin={spacerMargin}/>

                                                        {/* period */}
                                                        <FhirPeriod label="Duration the EpisodeOfCare was in the specified status"
                                                                    context={`statusHistory.${index}.period`}
                                                                    disabled={disabled}
                                                                    readonly={isPatient}/>

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

                                        {!isPatient && statusHistoryFieldArray.fields.length > 0 && (
                                            <Flex justify="center">
                                                <FlexItem>
                                                    <button type="button"
                                                            className={`btn btn-blue-ghost${disabled ? ' btn-busy' : ''}`}
                                                            onClick={addStatusHistory}
                                                            disabled={disabled}>
                                                        <PlusCircle className="w-4 h-4" />
                                                        Add Status History
                                                    </button>
                                                </FlexItem>
                                            </Flex>
                                        )}
                                    </div>
                                </Disabled>
                            );
                        }
                    }}
                </TabPanel>
            </CardBody>
        </Card>
    );
};

export default FhirEpisodeOfCare;