import {
  AddComponentLabels,
  RemoveComponentLabels,
} from '@atlassian/forge-graphql-types';
import { GqlSegment } from './types';
import generateMutationGql from '../generateMutationGql';

export default function updateLabelsSegment(
  componentId: string,
  oldLabels: Array<string> = [],
  newLabels: Array<string> = undefined,
): GqlSegment {
  let segmentAcc = {
    mutation: '',
    parameters: [] as Array<string>,
    variables: {},
  };
  // if newLabels is null, remove existing labels
  if (newLabels === undefined) {
    return segmentAcc;
  }
  newLabels = newLabels || [];

  const labelsInBoth = oldLabels.filter((existingLabel) =>
    newLabels.some((newLabel) => newLabel === existingLabel),
  );
  const toBeAdded = newLabels.filter(
    (newLabel) =>
      !labelsInBoth.some((overlapLabel) => newLabel === overlapLabel),
  );
  const toBeRemoved = oldLabels.filter(
    (oldLabel) =>
      !labelsInBoth.some((overlapLabel) => oldLabel === overlapLabel),
  );

  if (toBeAdded.length > 0) {
    const {
      mutationGql: addLabelsMutation,
      params: addLabelsParams,
      inputId: addLabelsInputId,
    } = generateMutationGql(AddComponentLabels, 'addComponentLabels');
    const variables = {} as Record<string, any>;
    variables[addLabelsInputId] = {
      componentId,
      labelNames: toBeAdded,
    };
    segmentAcc = {
      mutation: addLabelsMutation,
      parameters: addLabelsParams,
      variables,
    };
  }
  if (toBeRemoved.length > 0) {
    const {
      mutationGql: removeLabelsMutation,
      params: removeLabelsParams,
      inputId: removeLabelsInputId,
    } = generateMutationGql(RemoveComponentLabels, 'removeComponentLabels');
    const variables = {} as Record<string, any>;
    variables[removeLabelsInputId] = {
      componentId,
      labelNames: toBeRemoved,
    };
    segmentAcc = {
      mutation: segmentAcc.mutation + removeLabelsMutation,
      parameters: [...segmentAcc.parameters, ...removeLabelsParams],
      variables: {
        ...segmentAcc.variables,
        ...variables,
      },
    };
  }
  return segmentAcc;
}