ana-ledger/ana/legacy_contributions.go

125 lines
3.4 KiB
Go

package ana
import (
"maps"
"slices"
"sort"
"time"
"gogs.inhome.blapointe.com/ana-ledger/ledger"
)
func RegisterWithContributionPrediction(reg ledger.Register, window time.Duration) (ledger.Register, error) {
result := make(ledger.Register)
result.PushAll(reg)
for _, name := range result.Names() {
err := registerWithContributionPredictionForName(result, window, name)
if err != nil {
return nil, err
}
}
return result, nil
}
func registerWithContributionPredictionForName(reg ledger.Register, window time.Duration, name string) error {
latest := make(ledger.Balance)
for _, d := range reg.Dates() {
if _, ok := reg[d][name]; ok {
latest = reg[d][name]
}
}
for _, predictionTime := range predictionTimes(window) {
k := predictionTime.Format("2006-01")
if _, ok := reg[k]; !ok {
reg[k] = make(ledger.Balances)
}
reg[k][name] = maps.Clone(latest)
}
for c := range latest {
err := registerWithContributionPredictionForNameForCurrency(reg, window, name, c)
if err != nil {
return err
}
}
return nil
}
func registerWithContributionPredictionForNameForCurrency(reg ledger.Register, window time.Duration, name string, currency ledger.Currency) error {
type contribution struct {
t time.Time
v float64
}
contributions := make([]contribution, 0)
for d := range reg {
t, err := dateToTime(d)
if err != nil {
return err
}
if time.Since(t) > time.Hour*24*180 || time.Now().Before(t) { // only include -6months..now
continue
}
if v, ok := reg[d][name][currency]; ok && (len(contributions) == 0 || contributions[len(contributions)-1].v != v) {
contributions = append(contributions, contribution{t: t, v: v})
}
}
sort.Slice(contributions, func(i, j int) bool {
return contributions[i].t.Before(contributions[j].t)
})
if len(contributions) < 5 {
return nil
}
getMedianValueDelta := func(contributions []contribution) float64 {
values := make([]float64, len(contributions))
for i := 1; i < len(contributions); i++ {
values[i] = contributions[i].v - contributions[i-1].v
}
slices.Sort(values)
return values[len(values)/2]
}
getMedianLapse := func(contributions []contribution) time.Duration {
lapses := make([]time.Duration, len(contributions)-1)
for i := 1; i < len(contributions); i++ {
lapses = append(lapses, contributions[i].t.Sub(contributions[i-1].t))
}
slices.Sort(lapses)
return lapses[len(lapses)/2]
}
contributionsSlice := func(percent float64) []contribution {
wouldBe := int(percent * float64(len(contributions)))
if wouldBe == 0 {
wouldBe = 2
}
return contributions[len(contributions)-1-wouldBe:]
}
eighth := contributionsSlice(7.0 / 8.0)
quarter := contributionsSlice(3.0 / 4.0)
half := contributionsSlice(1.0 / 2.0)
medianValueDelta := func() float64 {
medians := []float64{
getMedianValueDelta(eighth),
getMedianValueDelta(quarter),
getMedianValueDelta(half),
}
slices.Sort(medians)
return medians[1]
}()
medianLapse := func() time.Duration {
medians := []time.Duration{
getMedianLapse(eighth),
getMedianLapse(quarter),
getMedianLapse(half),
}
slices.Sort(medians)
return medians[1]
}()
for _, predictionTime := range predictionTimes(window) {
k := predictionTime.Format("2006-01")
expectedDelta := float64(predictionTime.Sub(time.Now())) * medianValueDelta / float64(medianLapse)
reg[k][name][currency] += expectedDelta
}
return nil
}