/**
 * 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 Dma {
  dma?: number;
  ama?: number;
}

/**
 * DMA
 * 公式：DIF:MA(CLOSE,N1)-MA(CLOSE,N2);DIFMA:MA(DIF,M)
 */
const differentOfMovingAverage: IndicatorTemplate<Dma> = {
  name: 'DMA',
  shortName: 'DMA',
  calcParams: [10, 50, 10],
  figures: [
    { key: 'dma', title: 'DMA: ', type: 'line' },
    { key: 'ama', title: 'AMA: ', type: 'line' },
  ],
  calc: (dataList: TViewData[], indicator: Indicator<Dma>) => {
    const params = indicator.calcParams as number[];
    const maxPeriod = Math.max(params[0], params[1]);
    let closeSum1 = 0;
    let closeSum2 = 0;
    let dmaSum = 0;
    const result: Dma[] = [];
    dataList.forEach((TViewData: TViewData, i: number) => {
      const dma: Dma = {};
      const close = TViewData.close;
      closeSum1 += close;
      closeSum2 += close;
      let ma1 = 0;
      let ma2 = 0;
      if (i >= params[0] - 1) {
        ma1 = closeSum1 / params[0];
        closeSum1 -= dataList[i - (params[0] - 1)].close;
      }
      if (i >= params[1] - 1) {
        ma2 = closeSum2 / params[1];
        closeSum2 -= dataList[i - (params[1] - 1)].close;
      }

      if (i >= maxPeriod - 1) {
        const dif = ma1 - ma2;
        dma.dma = dif;
        dmaSum += dif;
        if (i >= maxPeriod + params[2] - 2) {
          dma.ama = dmaSum / params[2];
          dmaSum -= result[i - (params[2] - 1)].dma ?? 0;
        }
      }
      result.push(dma);
    });
    return result;
  },
};

export default differentOfMovingAverage;