/**
 * 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 type TViewData from '../../common/TViewData';
import {
  type Indicator,
  type IndicatorTemplate,
} from '../../component/Indicator';

interface Mtm {
  mtm?: number;
  maMtm?: number;
}

/**
 * mtm
 * 公式 MTM（N日）=C－CN
 */
const momentum: IndicatorTemplate<Mtm> = {
  name: 'MTM',
  shortName: 'MTM',
  calcParams: [12, 6],
  figures: [
    { key: 'mtm', title: 'MTM: ', type: 'line' },
    { key: 'maMtm', title: 'MAMTM: ', type: 'line' },
  ],
  calc: (dataList: TViewData[], indicator: Indicator<Mtm>) => {
    const params = indicator.calcParams as number[];
    let mtmSum = 0;
    const result: Mtm[] = [];
    dataList.forEach((TViewData: TViewData, i: number) => {
      const mtm: Mtm = {};
      if (i >= params[0]) {
        const close = TViewData.close;
        const agoClose = dataList[i - params[0]].close;
        mtm.mtm = close - agoClose;
        mtmSum += mtm.mtm;
        if (i >= params[0] + params[1] - 1) {
          mtm.maMtm = mtmSum / params[1];
          mtmSum -= result[i - (params[1] - 1)].mtm ?? 0;
        }
      }
      result.push(mtm);
    });
    return result;
  },
};

export default momentum;