// @rewire
import isEqual from 'lodash-es/isEqual';

import type {
  AttributeJson,
  HtmlAttributeJson,
  LinkAttributeJson,
  LinklistAttributeJson,
} from 'scrivito_sdk/client';
import { ObjData } from 'scrivito_sdk/data';
import {
  convertHtml,
  convertLink,
  convertLinklist,
} from 'scrivito_sdk/link_resolution/content_conversion';
import { load, loadableWithDefault } from 'scrivito_sdk/loadable';

export type AnyLinkResolutionAttributeJson =
  | HtmlAttributeJson
  | LinkAttributeJson
  | LinklistAttributeJson;

export function isAnyLinkResolutionAttributeJson(
  attributeData: AttributeJson
): attributeData is AnyLinkResolutionAttributeJson {
  return ['html', 'link', 'linklist'].includes(attributeData[0]);
}

export async function runWorker(
  attributeDataToConvert: AnyLinkResolutionAttributeJson,
  objData: ObjData,
  attributeName: string,
  widgetId?: string
): Promise<void> {
  const convertValue = getConversion(attributeDataToConvert);
  const convertedDataWithoutLoading = loadableWithDefault(
    undefined,
    convertValue
  );
  if (convertedDataWithoutLoading !== undefined) {
    if (!isEqual(convertedDataWithoutLoading, attributeDataToConvert)) {
      update(objData, attributeName, widgetId, convertedDataWithoutLoading);
    }

    return;
  }

  const convertedData = await load(convertValue);
  if (isEqual(convertedData, attributeDataToConvert)) return;

  if (
    hasDataToConvertBeenChangedConcurrently(
      attributeDataToConvert,
      objData,
      attributeName,
      widgetId
    )
  ) {
    return;
  }

  update(objData, attributeName, widgetId, convertedData);
}

function hasDataToConvertBeenChangedConcurrently(
  attributeData: AnyLinkResolutionAttributeJson,
  objData: ObjData,
  attributeName: string,
  widgetId: string | undefined
) {
  const currentAttributeData = widgetId
    ? objData.getWidgetAttribute(widgetId, attributeName)
    : objData.getAttribute(attributeName);

  return !isEqual(attributeData, currentAttributeData);
}

function update(
  objData: ObjData,
  attributeName: string,
  widgetId: string | undefined,
  newData: AnyLinkResolutionAttributeJson
) {
  const patch = { [attributeName]: newData };

  if (widgetId) {
    objData.update({
      _widget_pool: {
        [widgetId]: patch,
      },
    });
  } else {
    objData.update(patch);
  }
}

// The precise type is getConversion<T extends_oneof AnyLinkResolutionAttributeJson>(attributeData: T): () => T
// See https://github.com/microsoft/TypeScript/issues/27808
function getConversion(
  attributeData: AnyLinkResolutionAttributeJson
): () => typeof attributeData {
  switch (attributeData[0]) {
    case 'html': {
      const attributeValue = attributeData[1];
      return () => ['html', convertHtml(attributeValue)];
    }
    case 'link': {
      const attributeValue = attributeData[1];
      return () => ['link', convertLink(attributeValue)];
    }
    case 'linklist': {
      const attributeValue = attributeData[1];
      return () => ['linklist', convertLinklist(attributeValue)];
    }
  }
}