/*
 * Copyright 2025 Commonwealth Scientific and Industrial Research
 * Organisation (CSIRO) ABN 41 687 119 230.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import React, { useContext, useMemo } from 'react';
import { RepeatGroupContainerStack } from '../RepeatItem/RepeatItem.styles';
import Box from '@mui/material/Box';
import GroupItem from '../GroupItem/GroupItem';
import { RepeatGroupInstanceContext } from '../../../contexts/RepeatGroupInstanceContext';
import { appendRepeatInstanceIndex } from '../../../utils/validateErrorKey';
import type {
  PropsWithParentIsReadOnlyAttribute,
  PropsWithQrItemChangeHandler
} from '../../../interfaces/renderProps.interface';
import type { QuestionnaireItem, QuestionnaireResponseItem } from 'fhir/r4';
import RemoveItemButton from './RemoveItemButton';
import useReadOnly from '../../../hooks/useReadOnly';

interface RepeatGroupItemProps
  extends PropsWithQrItemChangeHandler,
    PropsWithParentIsReadOnlyAttribute {
  qItem: QuestionnaireItem;
  repeatGroupIndex: number;
  /** This instance's index within the QuestionnaireResponse, or null if it isn't in the QR yet */
  qrInstanceIndex: number | null;
  answeredQrItem: QuestionnaireResponseItem;
  nullableQrItem: QuestionnaireResponseItem | null;
  numOfRepeatGroups: number;
  groupCardElevation: number;
  onRemoveItem: () => void;
}

function RepeatGroupItem(props: RepeatGroupItemProps) {
  const {
    qItem,
    repeatGroupIndex,
    qrInstanceIndex,
    answeredQrItem,
    nullableQrItem,
    numOfRepeatGroups,
    groupCardElevation,
    parentIsReadOnly,
    onRemoveItem,
    onQrItemChange
  } = props;

  const readOnly = useReadOnly(qItem, parentIsReadOnly, repeatGroupIndex);

  // Append this instance's index to the enclosing repeat instance path so that descendant items look
  // up their own instance-scoped validation errors (see useValidationFeedback). Uses the
  // QuestionnaireResponse index, not repeatGroupIndex, because that is what validation walks.
  // Memoised to keep the provided context value referentially stable, so that memoising a descendant
  // item in future actually lets it bail out of a re-render.
  const parentRepeatInstancePath = useContext(RepeatGroupInstanceContext);
  const repeatInstancePath = useMemo(
    () => appendRepeatInstanceIndex(parentRepeatInstancePath, qrInstanceIndex),
    [parentRepeatInstancePath, qrInstanceIndex]
  );

  return (
    <RepeatGroupInstanceContext.Provider value={repeatInstancePath}>
      <RepeatGroupContainerStack direction="row">
        <Box sx={{ flexGrow: 1, overflowX: 'auto' }}>
          <GroupItem
            qItem={qItem}
            qrItem={answeredQrItem}
            isRepeated={true}
            parentIsRepeatGroup={true}
            parentRepeatGroupIndex={repeatGroupIndex}
            parentIsReadOnly={parentIsReadOnly}
            groupCardElevation={groupCardElevation}
            onQrItemChange={onQrItemChange}
          />
        </Box>
        <RemoveItemButton
          nullableQrItem={nullableQrItem}
          numOfRepeatGroups={numOfRepeatGroups}
          readOnly={readOnly}
          onRemoveItem={onRemoveItem}
        />
      </RepeatGroupContainerStack>
    </RepeatGroupInstanceContext.Provider>
  );
}

export default RepeatGroupItem;