prediction about to test

ana/prediction.go

@@ -1,3 +1,44 @@
 package ana
 
+import (
+	"maps"
+	"time"
+
+	"gogs.inhome.blapointe.com/ana-ledger/ledger"
+)
+
 type Prediction []Predictor
+
+func NewPrediction(predictor ...Predictor) Prediction {
+	return Prediction(predictor)
+}
+
+func (prediction Prediction) Predict(register ledger.Register, window time.Duration) ledger.Register {
+	return prediction.predict(register.Latest(), time.Now(), predictionTimes(window))
+}
+
+func (prediction Prediction) predict(latest ledger.Balances, from time.Time, these []time.Time) ledger.Register {
+	latestT := from
+	result := make(ledger.Register)
+	for i := range these {
+		k := these[i].Format("2006-01")
+		result[k] = make(ledger.Balances)
+		for k2, v2 := range result[k] {
+			result[k][k2] = maps.Clone(v2)
+		}
+
+		elapsed := these[i].Sub(latestT)
+		result[k] = prediction.predictOne(result[k], elapsed)
+
+		latest = result[k]
+		latestT = these[i]
+	}
+	return result
+}
+
+func (prediction Prediction) predictOne(balances ledger.Balances, elapsed time.Duration) ledger.Balances {
+	for i := range prediction {
+		balances = prediction[i](balances, elapsed)
+	}
+	return balances
+}