wip ledger/register.go

ledger/register.go

@@ -0,0 +1,57 @@
+package ledger
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"slices"
+	"time"
+)
+
+func RegisterWithContributionPrediction(reg map[string]Balances, windowAsPercentOfTotalDuration float64) (map[string]Balances, error) {
+	times, err := registerTimesInUnix(reg)
+	if err != nil {
+		return nil, err
+	}
+	windowDuration := time.Second * time.Duration(float64(slices.Max(times)-slices.Min(times))*windowAsPercentOfTotalDuration)
+	log.Println(windowDuration)
+
+	lastReal := time.Unix(slices.Max(times), 0)
+	lastPredicted := lastReal
+	for lastPredicted.Before(lastReal.Add(windowDuration)) {
+		lastPredicted = lastPredicted.Add(time.Hour * 24 * time.Duration((45 - lastPredicted.Day())))
+		log.Println(lastPredicted)
+	}
+
+	result := make(map[string]Balances)
+	return result, io.EOF
+}
+
+func RegisterWithCompoundingInterestPrediction(reg map[string]Balances, windowAsPercentOfTotalDuration float64, name string, rate float64) (map[string]Balances, error) {
+	result := make(map[string]Balances)
+	return result, io.EOF
+}
+
+func registerTimesInUnix(reg map[string]Balances) ([]int64, error) {
+	result := make([]int64, 0, len(reg))
+	for k := range reg {
+		v, err := registerTime(k)
+		if err != nil {
+			return nil, err
+		}
+		result = append(result, v.Unix())
+	}
+	return result, nil
+}
+
+func registerTime(s string) (time.Time, error) {
+	for _, layout := range []string{
+		"2006-01-02",
+		"2006-01",
+	} {
+		if t, err := time.ParseInLocation(layout, s, time.Local); err == nil {
+			return t, err
+		}
+	}
+	return time.Time{}, fmt.Errorf("no layout matching %q", s)
+}

ledger/register_test.go

@@ -0,0 +1,39 @@
+package ledger
+
+import (
+	"testing"
+)
+
+func TestRegisterPredictContribution(t *testing.T) {
+	// 1n t0 w weight 4
+	// 2n t1 w weight 2
+	// 4n t2 w weight 1
+	input := map[string]Balances{
+		"2001-01": Balances{"X": Balance{USD: 1}},
+		"2001-02": Balances{"X": Balance{USD: 2}},
+		"2001-03": Balances{"X": Balance{USD: 3}},
+		"2001-04": Balances{"X": Balance{USD: 4}},
+		"2001-05": Balances{"X": Balance{USD: 5}},
+		"2001-06": Balances{"X": Balance{USD: 6}},
+		"2001-07": Balances{"X": Balance{USD: 8}},
+		"2001-08": Balances{"X": Balance{USD: 10}},
+		"2001-09": Balances{"X": Balance{USD: 12}},
+		"2001-10": Balances{"X": Balance{USD: 16}},
+	}
+	// 1x4 weight 4 = 16
+	// 2x2 weight 2 = 8
+	// 4x1 weight 1 = 4
+	// (16+8+4) / (4+2+1) = 4
+	got, err := RegisterWithContributionPrediction(input, .12)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != len(input)+1 {
+		t.Error(len(got))
+	}
+	if balance, ok := got["2001-11"]; !ok {
+		t.Error(ok)
+	} else if balance["X"][USD] != 20.0 {
+		t.Error(balance)
+	}
+}