Dev backtest (#1134)

backtest/datafeed.go

@@ -0,0 +1,194 @@
+package backtest
+
+import (
+	"fmt"
+	"sort"
+	"time"
+
+	"nofx/market"
+)
+
+type timeframeSeries struct {
+	klines     []market.Kline
+	closeTimes []int64
+}
+
+type symbolSeries struct {
+	byTF map[string]*timeframeSeries
+}
+
+// DataFeed 管理历史K线数据，为回测提供按时间推进的快照。
+type DataFeed struct {
+	cfg           BacktestConfig
+	symbols       []string
+	timeframes    []string
+	symbolSeries  map[string]*symbolSeries
+	decisionTimes []int64
+	primaryTF     string
+	longerTF      string
+}
+
+func NewDataFeed(cfg BacktestConfig) (*DataFeed, error) {
+	df := &DataFeed{
+		cfg:          cfg,
+		symbols:      make([]string, len(cfg.Symbols)),
+		timeframes:   append([]string(nil), cfg.Timeframes...),
+		symbolSeries: make(map[string]*symbolSeries),
+		primaryTF:    cfg.DecisionTimeframe,
+	}
+	copy(df.symbols, cfg.Symbols)
+
+	if err := df.loadAll(); err != nil {
+		return nil, err
+	}
+
+	return df, nil
+}
+
+func (df *DataFeed) loadAll() error {
+	start := time.Unix(df.cfg.StartTS, 0)
+	end := time.Unix(df.cfg.EndTS, 0)
+
+	// longest timeframe用于辅助指标
+	var longestDur time.Duration
+	for _, tf := range df.timeframes {
+		dur, err := market.TFDuration(tf)
+		if err != nil {
+			return err
+		}
+		if dur > longestDur {
+			longestDur = dur
+			df.longerTF = tf
+		}
+	}
+
+	for _, symbol := range df.symbols {
+		ss := &symbolSeries{byTF: make(map[string]*timeframeSeries)}
+		for _, tf := range df.timeframes {
+			dur, _ := market.TFDuration(tf)
+			buffer := dur * 200
+			fetchStart := start.Add(-buffer)
+			if fetchStart.Before(time.Unix(0, 0)) {
+				fetchStart = time.Unix(0, 0)
+			}
+			fetchEnd := end.Add(dur)
+
+			klines, err := market.GetKlinesRange(symbol, tf, fetchStart, fetchEnd)
+			if err != nil {
+				return fmt.Errorf("fetch klines for %s %s: %w", symbol, tf, err)
+			}
+			if len(klines) == 0 {
+				return fmt.Errorf("no klines for %s %s", symbol, tf)
+			}
+
+			series := &timeframeSeries{
+				klines:     klines,
+				closeTimes: make([]int64, len(klines)),
+			}
+			for i, k := range klines {
+				series.closeTimes[i] = k.CloseTime
+			}
+			ss.byTF[tf] = series
+		}
+		df.symbolSeries[symbol] = ss
+	}
+
+	// 以第一个符号的主周期生成回测进度时间轴
+	firstSymbol := df.symbols[0]
+	primarySeries := df.symbolSeries[firstSymbol].byTF[df.primaryTF]
+	startMs := start.UnixMilli()
+	endMs := end.UnixMilli()
+	for _, ts := range primarySeries.closeTimes {
+		if ts < startMs {
+			continue
+		}
+		if ts > endMs {
+			break
+		}
+		df.decisionTimes = append(df.decisionTimes, ts)
+		// 对齐其他符号，如果缺数据则提前报错
+		for _, symbol := range df.symbols[1:] {
+			if _, ok := df.symbolSeries[symbol].byTF[df.primaryTF]; !ok {
+				return fmt.Errorf("symbol %s missing timeframe %s", symbol, df.primaryTF)
+			}
+		}
+	}
+	if len(df.decisionTimes) == 0 {
+		return fmt.Errorf("no decision bars in range")
+	}
+	return nil
+}
+
+func (df *DataFeed) DecisionBarCount() int {
+	return len(df.decisionTimes)
+}
+
+func (df *DataFeed) DecisionTimestamp(index int) int64 {
+	return df.decisionTimes[index]
+}
+
+func (df *DataFeed) sliceUpTo(symbol, tf string, ts int64) []market.Kline {
+	series := df.symbolSeries[symbol].byTF[tf]
+	idx := sort.Search(len(series.closeTimes), func(i int) bool {
+		return series.closeTimes[i] > ts
+	})
+	if idx <= 0 {
+		return nil
+	}
+	return series.klines[:idx]
+}
+
+func (df *DataFeed) BuildMarketData(ts int64) (map[string]*market.Data, map[string]map[string]*market.Data, error) {
+	result := make(map[string]*market.Data, len(df.symbols))
+	multi := make(map[string]map[string]*market.Data, len(df.symbols))
+
+	for _, symbol := range df.symbols {
+		perTF := make(map[string]*market.Data, len(df.timeframes))
+		for _, tf := range df.timeframes {
+			series := df.sliceUpTo(symbol, tf, ts)
+			if len(series) == 0 {
+				continue
+			}
+			var longer []market.Kline
+			if df.longerTF != "" && df.longerTF != tf {
+				longer = df.sliceUpTo(symbol, df.longerTF, ts)
+			}
+			data, err := market.BuildDataFromKlines(symbol, series, longer)
+			if err != nil {
+				return nil, nil, err
+			}
+			perTF[tf] = data
+			if tf == df.primaryTF {
+				result[symbol] = data
+			}
+		}
+		if _, ok := perTF[df.primaryTF]; !ok {
+			return nil, nil, fmt.Errorf("no primary data for %s at %d", symbol, ts)
+		}
+		multi[symbol] = perTF
+	}
+	return result, multi, nil
+}
+
+func (df *DataFeed) decisionBarSnapshot(symbol string, ts int64) (*market.Kline, *market.Kline) {
+	ss, ok := df.symbolSeries[symbol]
+	if !ok {
+		return nil, nil
+	}
+	series, ok := ss.byTF[df.primaryTF]
+	if !ok {
+		return nil, nil
+	}
+	idx := sort.Search(len(series.closeTimes), func(i int) bool {
+		return series.closeTimes[i] >= ts
+	})
+	if idx >= len(series.closeTimes) || series.closeTimes[idx] != ts {
+		return nil, nil
+	}
+	curr := &series.klines[idx]
+	var next *market.Kline
+	if idx+1 < len(series.klines) {
+		next = &series.klines[idx+1]
+	}
+	return curr, next
+}