/**
 * 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 Rsi {
  rsi1?: number;
  rsi2?: number;
  rsi3?: number;
}

/**
 * RSI
 * RSI = SUM(MAX(CLOSE - REF(CLOSE,1),0),N) / SUM(ABS(CLOSE - REF(CLOSE,1)),N) × 100
 */
const relativeStrengthIndex: IndicatorTemplate<Rsi> = {
  name: 'RSI',
  shortName: 'RSI',
  calcParams: [6, 12, 24],
  figures: [
    { key: 'rsi1', title: 'RSI1: ', type: 'line' },
    { key: 'rsi2', title: 'RSI2: ', type: 'line' },
    { key: 'rsi3', title: 'RSI3: ', type: 'line' },
  ],
  regenerateFigures: (params: any[]) => {
    return params.map((_: any, index: number) => {
      const num = index + 1;
      return { key: `rsi${num}`, title: `RSI${num}: `, type: 'line' };
    });
  },
  calc: (dataList: TViewData[], indicator: Indicator<Rsi>) => {
    const { calcParams: params, figures } = indicator;
    const sumCloseAs: number[] = [];
    const sumCloseBs: number[] = [];
    return dataList.map((TViewData, i) => {
      const rsi = {};
      const prevClose = (dataList[i - 1] ?? TViewData).close;
      const tmp = TViewData.close - prevClose;
      params.forEach((p, index) => {
        if (tmp > 0) {
          sumCloseAs[index] = (sumCloseAs[index] ?? 0) + tmp;
        } else {
          sumCloseBs[index] = (sumCloseBs[index] ?? 0) + Math.abs(tmp);
        }
        if (i >= p - 1) {
          if (sumCloseBs[index] !== 0) {
            rsi[figures[index].key] =
              100 - 100.0 / (1 + sumCloseAs[index] / sumCloseBs[index]);
          } else {
            rsi[figures[index].key] = 0;
          }
          const agoData = dataList[i - (p - 1)];
          const agoPreData = dataList[i - p] ?? agoData;
          const agoTmp = agoData.close - agoPreData.close;
          if (agoTmp > 0) {
            sumCloseAs[index] -= agoTmp;
          } else {
            sumCloseBs[index] -= Math.abs(agoTmp);
          }
        }
      });
      return rsi;
    });
  },
};

export default relativeStrengthIndex;