import { availableRecordEmpty, useChartRecordStanding } from '../../../../hooks/useRecordAccessStanding';
import { useProxyCannotAddToRecord } from '../../../../hooks/useProxyCannotAddToRecord';
import { useState } from 'react';
import { Item, ItemGroup } from "../../../../components/ui/item-group";
import { useNavigate } from 'react-router-dom';
import { Icon } from "../../../../components/ui/icon";
import { Flex, FlexItem, FlexBlock } from '../../../../components/ui/flex';
import { Text } from '../../../../components/ui/text';
import { Spacer } from '../../../../components/ui/spacer';
// `info` is KEPT: it feeds the WordPress icon component on each row as well as the Help
// button. Dropping it because "its Button was converted" would break the row icon.
import { Pencil, Plus, Info as info } from 'lucide-react';
import { Condition } from 'fhir/r4';
import { AppSpinner, FhirConditionDisplay, ScrollableTab } from '../../../../components';
import { ResourceListStatus } from '../../../../components/ui/resource-list-status';
import { useFhirConditionBroadcast, useFhirConditions, useFhirConditionTargetedBroadcast, useRequestRecordCorrection } from '../../../../hooks';
import { isConditionRecordedByCareTeam, resolveConditionAuthorReference } from '../../../../utils/messaging/requestCorrection';
import { formatFhirCodeableConcept } from '../../../../utils/fhirCodeableConcept.tsx';
import { useAuthServiceContext, useConditionServiceContext } from '../../../../services';
import { mayEditRecord } from '../../../../utils/recordEditability';
import { useSeatStanding } from '../../../../utils/seatStanding';
import { SourcePractice } from '../../../../components/ui/source-practice';
import { RecordPracticeNote, recordPracticeId, useRecordPracticeView, useRetireOnPracticeChange } from '../../../../contexts/RecordPracticeContext';

const Conditions = () => {
    const { standing: recordStanding } = useChartRecordStanding();
    const navigate = useNavigate();
    const { userRole, USER_ROLES, practitionerRoles } = useAuthServiceContext();
    const seatStanding = useSeatStanding();
    const { getConditionDisplay } = useConditionServiceContext();
    const { loading, error, clearError, conditionsList, attempted, freshness: recordFreshness } = useFhirConditions();
    const [selectedCondition, setSelectedCondition] = useState<Condition | null>(null);
    const [showDisplayModal, setShowDisplayModal] = useState<boolean>(false);
    // The record's practice context: its own conditions under a named practice; the empty state speaks for the whole record.
    const practiceView = useRecordPracticeView(conditionsList, recordPracticeId);
    useRetireOnPracticeChange(() => { setShowDisplayModal(false); setSelectedCondition(null); });

    useFhirConditionBroadcast();
    useFhirConditionTargetedBroadcast({
        condition: selectedCondition || undefined,
        isOpen: showDisplayModal,
        onUpdate: (updatedCondition) => {
            setSelectedCondition(updatedCondition);
        },
        onDelete: () => {
            setShowDisplayModal(false);
            setSelectedCondition(null);
        }
    });

    const viewCondition = (condition: Condition) => {
        setSelectedCondition(condition);
        setShowDisplayModal(true);
    };

    const editCondition = (event: React.MouseEvent, condition: Condition) => {
        event.stopPropagation();
        navigate(condition.id as string, { relative: 'route' });
    };

    const addCondition = () => {
        navigate('new', { relative: 'route' });
    };

    const roleAllowsEdit = () => {
        return userRole && [USER_ROLES.PATIENT, USER_ROLES.RELATED_PERSON, USER_ROLES.PRACTITIONER].includes(userRole as string);
    };

    /*
     * AND THE ROLE IS NOT THE RULE THE SERVER APPLIES.
     *
     * Writing a Condition needs a paid clinician seat, resolved per request by `callerMayWrite`. The role
     * check above passes for an unseated practitioner - a medical assistant, a nurse rooming patients,
     * somebody whose seat was turned off this morning - so the page offered Add and Edit, and the save
     * came back refused. A refusal that arrives after the typing has already spent the work.
     */
    const seat = mayEditRecord({ seatStanding,
        resourceType: 'Condition',
        viewerIsStaff: Boolean(userRole)
            && ![USER_ROLES.PATIENT, USER_ROLES.RELATED_PERSON].includes(userRole as string),
        practitionerRoles,
    });

    const proxyCannotAdd = useProxyCannotAddToRecord();
    const isAuthorizedToEdit = () => roleAllowsEdit() && seat.mayEdit && !proxyCannotAdd;

    /*
     * A CONDITION THE CARE TEAM RECORDED IS NOT THE PATIENT'S TO EDIT, and the server refuses the edit:
     * "You can only edit health concerns you added. This record is managed by your care team." The row knows
     * who recorded it, so the patient's side is not offered the edit. A row with no recorder keeps Edit - the
     * server decides.
     */
    const viewerIsPatientSide = [USER_ROLES.PATIENT, USER_ROLES.RELATED_PERSON].includes(userRole as string);
    const recordedByCareTeam = isConditionRecordedByCareTeam;
    const mayEditRow = (condition: Condition) =>
        isAuthorizedToEdit() && !(viewerIsPatientSide && recordedByCareTeam(condition));

    const { requestCorrection, error: correctionError, recovery: correctionRecovery } = useRequestRecordCorrection(
        selectedCondition ? resolveConditionAuthorReference(selectedCondition) : undefined);
    const mayRequestCorrection = Boolean(selectedCondition) && viewerIsPatientSide && recordedByCareTeam(selectedCondition as Condition);
    const handleRequestCorrection = async (note: string) => {
        if (!selectedCondition) return { ok: false };
        const label = formatFhirCodeableConcept(selectedCondition.code) || 'this condition';
        return requestCorrection(resolveConditionAuthorReference(selectedCondition), label, note);
    };

    const getConditionStatusInfo = (condition: Condition) => {
        const clinicalStatusCode = condition.clinicalStatus?.coding?.[0]?.code ?? '';
        const isActive = clinicalStatusCode === 'active';
        const isResolved = clinicalStatusCode === 'resolved' || clinicalStatusCode === 'remission';
        return { isActive, isResolved };
    };

    const getConditionDateInfo = (condition: Condition): string => {
        if (condition.onsetDateTime) {
            return `Onset: ${new Date(condition.onsetDateTime).toLocaleDateString()}`;
        } else if (condition.recordedDate) {
            return `Recorded: ${new Date(condition.recordedDate).toLocaleDateString()}`;
        }
        return '';
    };

    return (
        <div>

            <Flex align="center" justify="space-between">
                <FlexBlock>
                </FlexBlock>
                
                {/* SAID, NOT WITHHELD. A control that simply disappears reads as a broken screen or as a
                    permission the reader has lost, and both send them to an administrator to check permissions
                    that are already correct. A seat is nameable, and a practice can enable one in a minute. */}
                {roleAllowsEdit() && !seat.mayEdit && (
                    <p className="text-sm text-secondary max-w-[22rem] text-right">{seat.reason}</p>
                )}
                {isAuthorizedToEdit() && (
                    <FlexItem>
                        <button
                            type="button"
                            className="btn btn-blue"
                            onClick={addCondition}
                        >
                            <Plus />
                            Add
                        </button>
                    </FlexItem>
                )}
            </Flex>
            <Spacer margin="8"/>

            <ResourceListStatus
                loading={loading}
                error={error}
                isEmpty={conditionsList.length === 0}

                /* - without this the empty message is a claim about the patient's
 record made before the server was ever asked. */
                attempted={attempted}
                resourceLabel="conditions"
                emptyMessage={availableRecordEmpty("No health conditions found.", recordStanding, recordFreshness)}
                onDismissError={clearError}
            />

            <>
                {loading ? (
                    <AppSpinner/>
                ) : (
                    <ScrollableTab>
                        <RecordPracticeNote view={practiceView} />
                        {practiceView.shown.length !== 0 && (
                            <ItemGroup isBordered isSeparated isRounded size='large'>
                                {practiceView.shown.map((condition: Condition) => {
                                    const displayTitle = getConditionDisplay(condition);
                                    const statusInfo = getConditionStatusInfo(condition);
                                    const dateInfo = getConditionDateInfo(condition);

                                    return (
                                        <Item key={condition.id}
                                              onClick={() => viewCondition(condition)}>
                                            <Flex>
                                                <FlexItem>
                                                    <Icon icon={info}
                                                          size={24}
                                                          style={{
                                                              marginRight: 12,
                                                              color: statusInfo.isActive ? 'var(--danger)' : statusInfo.isResolved ? '#00a32a' : undefined
                                                          }} />
                                                </FlexItem>
                                                <FlexBlock>
                                                    <Flex align="center" justify="space-between">
                                                        <FlexItem>
                                                            <Text style={{ fontWeight: 500 }}>
                                                                {displayTitle}
                                                            </Text>
                                                            {dateInfo && (
                                                                <Text variant="muted" style={{ display: 'block' }}>
                                                                    {dateInfo}
                                                                </Text>
                                                            )}
                                                            <Text variant="muted" style={{ display: 'block' }}><SourcePractice resource={condition} /></Text>
                                                        </FlexItem>
                                                        {mayEditRow(condition) && (
                                                            <FlexItem>
                                                                <button
                                                                    type="button"
                                                                    className="btn btn-blue-ghost-sm"
                                                                    onClick={(event: React.MouseEvent) => editCondition(event, condition)}
                                                                >
                                                                    <Pencil />
                                                                    Edit
                                                                </button>
                                                            </FlexItem>
                                                        )}
                                                    </Flex>
                                                </FlexBlock>
                                            </Flex>
                                        </Item>
                                    );
                                })}
                            </ItemGroup>
                        )}
                    </ScrollableTab>
                )}
            </>

            {selectedCondition && (
                <FhirConditionDisplay
                    condition={selectedCondition}
                    isOpen={showDisplayModal}
                    onClose={() => {
                        setShowDisplayModal(false);
                        setSelectedCondition(null);
                    }}
                    onRequestCorrection={mayRequestCorrection ? handleRequestCorrection : undefined}
                    correctionError={correctionError}
                    correctionRecovery={correctionRecovery}
                />
            )}
        </div>
    );
};

export default Conditions;