Ichimoku cloud Javascript node

Ichimoku.js

const inputs = { tenkan: -9, kijun: -26, senkou: -52, chikou: -26 };

main['ichimoku_' + pair] = generateIchimoku(pair, false);
main['chikou_' + pair] = generateIchimoku(pair, true);

const generateIchimoku = (pair, isChikou) => {

    const high = isChikou ? main.high[pair].slice(0, inputs.chikou) : main.high[pair];
    const low = isChikou ? main.low[pair].slice(0, inputs.chikou) : main.low[pair];

    const getHi = val => Math.max(...high.slice(val));
    const getLo = val => Math.min(...low.slice(val));

    const tenkan = (getHi(inputs.tenkan) + getLo(inputs.tenkan)) / 2;
    const kijun = (getHi(inputs.kijun) + getLo(inputs.kijun)) / 2;

    const spliceTo = isChikou ? main.high[pair].length + inputs.chikou * 2 : main.high[pair].length + inputs.chikou;
    const tenkanOld = (Math.max(...high.slice(spliceTo + inputs.tenkan, spliceTo)) + Math.min(...low.slice(spliceTo + inputs.tenkan, spliceTo))) / 2;
    const kijunOld = (Math.max(...high.slice(spliceTo + inputs.kijun, spliceTo)) + Math.min(...low.slice(spliceTo + inputs.kijun, spliceTo))) / 2;
    const senkouA = (tenkanOld + kijunOld) / 2;
    const senkouB = (Math.max(...high.slice(spliceTo + inputs.senkou, spliceTo)) + Math.min(...low.slice(spliceTo + inputs.senkou, spliceTo))) / 2;
    
    return { tenkan, kijun, senkouA, senkouB };
};