btc-trading/src/api/dashboard/static/js/indicators/moving_average.js

// Self-contained Moving Average indicator with SMA/EMA/RMA/WMA/VWMA support
// Includes math, metadata, signal calculation, and base class

// Signal constants (defined in each indicator file)
const SIGNAL_TYPES = {
    BUY: 'buy',
    SELL: 'sell',
    HOLD: 'hold'
};

const SIGNAL_COLORS = {
    buy: '#26a69a',
    hold: '#787b86',
    sell: '#ef5350'
};

// Base class (inline replacement for BaseIndicator)
class BaseIndicator {
    constructor(config) {
        this.id = config.id;
        this.type = config.type;
        this.name = config.name;
        this.params = config.params || {};
        this.timeframe = config.timeframe || '1m';
        this.series = [];
        this.visible = config.visible !== false;
        this.cachedResults = null;
        this.cachedMeta = null;
        this.lastSignalTimestamp = null;
        this.lastSignalType = null;
    }
}

// Moving Average math (SMA/EMA/RMA/WMA/VWMA)
function calculateSMA(candles, period, source = 'close') {
    const results = new Array(candles.length).fill(null);
    let sum = 0;
    for (let i = 0; i < candles.length; i++) {
        sum += candles[i][source];
        if (i >= period) sum -= candles[i - period][source];
        if (i >= period - 1) results[i] = sum / period;
    }
    return results;
}

function calculateEMA(candles, period, source = 'close') {
    const multiplier = 2 / (period + 1);
    const results = new Array(candles.length).fill(null);
    let ema = 0;
    let sum = 0;
    for (let i = 0; i < candles.length; i++) {
        if (i < period) {
            sum += candles[i][source];
            if (i === period - 1) {
                ema = sum / period;
                results[i] = ema;
            }
        } else {
            ema = (candles[i][source] - ema) * multiplier + ema;
            results[i] = ema;
        }
    }
    return results;
}

function calculateRMA(candles, period, source = 'close') {
    const multiplier = 1 / period;
    const results = new Array(candles.length).fill(null);
    let rma = 0;
    let sum = 0;
    
    for (let i = 0; i < candles.length; i++) {
        if (i < period) {
            sum += candles[i][source];
            if (i === period - 1) {
                rma = sum / period;
                results[i] = rma;
            }
        } else {
            rma = (candles[i][source] - rma) * multiplier + rma;
            results[i] = rma;
        }
    }
    return results;
}

function calculateWMA(candles, period, source = 'close') {
    const results = new Array(candles.length).fill(null);
    const weightSum = (period * (period + 1)) / 2;
    
    for (let i = period - 1; i < candles.length; i++) {
        let sum = 0;
        for (let j = 0; j < period; j++) {
            sum += candles[i - j][source] * (period - j);
        }
        results[i] = sum / weightSum;
    }
    return results;
}

function calculateVWMA(candles, period, source = 'close') {
    const results = new Array(candles.length).fill(null);
    
    for (let i = period - 1; i < candles.length; i++) {
        let sumPV = 0;
        let sumV = 0;
        for (let j = 0; j < period; j++) {
            sumPV += candles[i - j][source] * candles[i - j].volume;
            sumV += candles[i - j].volume;
        }
        results[i] = sumV !== 0 ? sumPV / sumV : null;
    }
    return results;
}

// Signal calculation for Moving Average
function calculateMASignal(indicator, lastCandle, prevCandle, values) {
    const close = lastCandle.close;
    const ma = values?.ma;
    
    if (!ma && ma !== 0) {
        return null;
    }
    
    if (close > ma) {
        return {
            type: SIGNAL_TYPES.BUY,
            strength: Math.min(60 + ((close - ma) / ma) * 500, 100),
            value: close,
            reasoning: `Price (${close.toFixed(2)}) is above MA (${ma.toFixed(2)})`
        };
    } else if (close < ma) {
        return {
            type: SIGNAL_TYPES.SELL,
            strength: Math.min(60 + ((ma - close) / ma) * 500, 100),
            value: close,
            reasoning: `Price (${close.toFixed(2)}) is below MA (${ma.toFixed(2)})`
        };
    } else {
        return null;
    }
}

// MA Indicator class
export class MAIndicator extends BaseIndicator {
    constructor(config) {
        super(config);
        this.lastSignalTimestamp = null;
        this.lastSignalType = null;
    }

    calculate(candles) {
        const maType = (this.params.maType || 'SMA').toLowerCase();
        const period = this.params.period || 44;
        
        let maValues;
        
        switch (maType) {
            case 'sma':
                maValues = calculateSMA(candles, period, this.params.source || 'close');
                break;
            case 'ema':
                maValues = calculateEMA(candles, period, this.params.source || 'close');
                break;
            case 'rma':
                maValues = calculateRMA(candles, period, this.params.source || 'close');
                break;
            case 'wma':
                maValues = calculateWMA(candles, period, this.params.source || 'close');
                break;
            case 'vwma':
                maValues = calculateVWMA(candles, period, this.params.source || 'close');
                break;
            default:
                maValues = calculateSMA(candles, period, this.params.source || 'close');
        }
        
        return maValues.map(ma => ({ ma }));
    }
    
    getMetadata() {
        return {
            name: 'MA',
            description: 'Moving Average (SMA/EMA/RMA/WMA/VWMA)',
            inputs: [
                {
                    name: 'period',
                    label: 'Period',
                    type: 'number',
                    default: 44,
                    min: 1,
                    max: 500
                },
                {
                    name: 'maType',
                    label: 'MA Type',
                    type: 'select',
                    options: ['SMA', 'EMA', 'RMA', 'WMA', 'VWMA'],
                    default: 'SMA'
                }
            ],
            plots: [
                {
                    id: 'value',
                    color: '#2962ff',
                    title: 'MA',
                    style: 'solid',
                    width: 1
                }
            ],
            displayMode: 'overlay'
        };
    }
}

// Export signal function for external use
export { calculateMASignal };