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.
import { Pencil, Plus, Info as info } from 'lucide-react';
import { Procedure } from 'fhir/r4';
import { AppSpinner, FhirProcedureDisplay, ScrollableTab } from '../../../../components';
import { ResourceListStatus } from '../../../../components/ui/resource-list-status';
import { formatFhirCodeableConcept } from '../../../../utils/fhirCodeableConcept.tsx';
import { useFhirProcedureBroadcast, useFhirProcedures, useFhirProcedureTargetedBroadcast, useRequestRecordCorrection } from '../../../../hooks';
import { resolveProcedureAuthorReference } from '../../../../utils/messaging/requestCorrection';
import { useAuthServiceContext, useProcedureServiceContext } 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 Procedures = () => {
    const navigate = useNavigate();
    const { userRole, USER_ROLES, practitionerRoles } = useAuthServiceContext();
    const seatStanding = useSeatStanding();
    const { getProcedureDisplay } = useProcedureServiceContext();
    const { loading, error, clearError, proceduresList, attempted } = useFhirProcedures();
    const [selectedProcedure, setSelectedProcedure] = useState<Procedure | null>(null);
    const [showDisplayModal, setShowDisplayModal] = useState<boolean>(false);
    // The record's practice context: its own procedures under a named practice; the empty state speaks for the whole record.
    const practiceView = useRecordPracticeView(proceduresList, recordPracticeId);
    useRetireOnPracticeChange(() => { setShowDisplayModal(false); setSelectedProcedure(null); });

    useFhirProcedureBroadcast();
    useFhirProcedureTargetedBroadcast({
        procedure: selectedProcedure || undefined,
        isOpen: showDisplayModal,
        onUpdate: (updatedProcedure) => {
            setSelectedProcedure(updatedProcedure);
        },
        onDelete: () => {
            setShowDisplayModal(false);
            setSelectedProcedure(null);
        }
    });

    const viewProcedure = (procedure: Procedure) => {
        setSelectedProcedure(procedure);
        setShowDisplayModal(true);
    };

    const editProcedure = (event: React.MouseEvent, procedure: Procedure) => {
        event.stopPropagation();
        navigate(procedure.id as string, { relative: 'route' });
    };

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

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

    const isPatient = Boolean(userRole)
        && [USER_ROLES.PATIENT, USER_ROLES.RELATED_PERSON].includes(userRole as string);

    const { requestCorrection, error: correctionError, recovery: correctionRecovery } = useRequestRecordCorrection(
        selectedProcedure ? resolveProcedureAuthorReference(selectedProcedure) : undefined);
    const handleRequestCorrection = async (note: string) => {
        if (!selectedProcedure) return { ok: false };
        const label = formatFhirCodeableConcept(selectedProcedure.code) || 'this procedure';
        return requestCorrection(resolveProcedureAuthorReference(selectedProcedure), label, note);
    };

    /*
     * AND THE ROLE IS NOT THE RULE THE SERVER APPLIES.
     *
     * Writing a Procedure 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: 'Procedure',
        viewerIsStaff: Boolean(userRole)
            && ![USER_ROLES.PATIENT, USER_ROLES.RELATED_PERSON].includes(userRole as string),
        practitionerRoles,
    });

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

    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={addProcedure}
                        >
                            <Plus />
                            Add
                        </button>
                    </FlexItem>
                )}
            </Flex>
            <Spacer margin="8"/>

            <ResourceListStatus
                loading={loading}
                error={error}
                isEmpty={proceduresList.length === 0}
                resourceLabel="procedures"
                emptyMessage="No procedures found."
                onDismissError={clearError}
                /* - without this, "No procedures found." is said about a question nobody
 asked whenever the patient id has not resolved. */
                attempted={attempted}
            />

            <>
                {loading ? (
                    <AppSpinner/>
                ) : (
                    <ScrollableTab>
                        <RecordPracticeNote view={practiceView} />
                        {practiceView.shown.length !== 0 && (
                            <ItemGroup isBordered isSeparated isRounded size='large'>
                                {practiceView.shown.map((procedure: Procedure) => {
                                    const displayTitle = getProcedureDisplay(procedure);
                                    const category = procedure.category ? formatFhirCodeableConcept(procedure.category) : '';

                                    return (
                                        <Item key={procedure.id}
                                              onClick={() => viewProcedure(procedure)}>
                                            <Flex>
                                                <FlexItem>
                                                    <Icon icon={info}
                                                          size={24}
                                                          style={{ marginRight: 12 }}/>
                                                </FlexItem>
                                                <FlexBlock>
                                                    <Flex align="center" justify="space-between">
                                                        <FlexItem>
                                                            <Text style={{ fontWeight: 500 }}>
                                                                {displayTitle}
                                                            </Text>
                                                            {category && (
                                                                <Text variant="muted" style={{ display: 'block' }}>
                                                                    Category: {category}
                                                                </Text>
                                                            )}
                                                            <Text variant="muted" style={{ display: 'block' }}><SourcePractice resource={procedure} /></Text>
                                                        </FlexItem>
                                                        {isAuthorizedToEdit() && (
                                                            <FlexItem>
                                                                <button
                                                                    type="button"
                                                                    className="btn btn-blue-ghost-sm"
                                                                    onClick={(event: React.MouseEvent) => editProcedure(event, procedure)}
                                                                >
                                                                    <Pencil />
                                                                    Edit
                                                                </button>
                                                            </FlexItem>
                                                        )}
                                                    </Flex>
                                                </FlexBlock>
                                            </Flex>
                                        </Item>
                                    );
                                })}
                            </ItemGroup>
                        )}
                    </ScrollableTab>
                )}
            </>

            {selectedProcedure && (
                <FhirProcedureDisplay
                    procedure={selectedProcedure}
                    isOpen={showDisplayModal}
                    onClose={() => {
                        setShowDisplayModal(false);
                        setSelectedProcedure(null);
                    }}
                    onRequestCorrection={isPatient ? handleRequestCorrection : undefined}
                    correctionError={correctionError}
                    correctionRecovery={correctionRecovery}
                />
            )}
        </div>
    );
};

export default Procedures;