import { BaseIndicator } from './base.js';

export class StochasticIndicator extends BaseIndicator {
    calculate(candles) {
        const kPeriod = this.params.kPeriod || 14;
        const dPeriod = this.params.dPeriod || 3;
        const results = new Array(candles.length).fill(null);
        
        const kValues = new Array(candles.length).fill(null);
        
        for (let i = kPeriod - 1; i < candles.length; i++) {
            let lowest = Infinity;
            let highest = -Infinity;
            for (let j = 0; j < kPeriod; j++) {
                lowest = Math.min(lowest, candles[i-j].low);
                highest = Math.max(highest, candles[i-j].high);
            }
            const diff = highest - lowest;
            kValues[i] = diff === 0 ? 50 : ((candles[i].close - lowest) / diff) * 100;
        }
        
        for (let i = kPeriod + dPeriod - 2; i < candles.length; i++) {
            let sum = 0;
            for (let j = 0; j < dPeriod; j++) sum += kValues[i-j];
            results[i] = { k: kValues[i], d: sum / dPeriod };
        }
        
        return results;
    }
    
    getMetadata() {
        return {
            name: 'Stochastic',
            description: 'Stochastic Oscillator - compares close to high-low range',
            inputs: [
                { name: 'kPeriod', label: 'K Period', type: 'number', default: 14 },
                { name: 'dPeriod', label: 'D Period', type: 'number', default: 3 }
            ],
            plots: [
                { id: 'k', color: '#3f51b5', title: '%K' },
                { id: 'd', color: '#ff9800', title: '%D' }
            ]
        };
    }
}