ana-ledger/ana/predictor.go

38 lines
916 B
Go

package ana
import (
"maps"
"math"
"regexp"
"time"
"gogs.inhome.blapointe.com/ana-ledger/ledger"
)
type Predictor func(ledger.Balances, time.Duration) ledger.Balances
func NewInterestPredictor(namePattern string, currencyPattern string, apy float64) Predictor {
nameMatcher := regexp.MustCompile(namePattern)
currencyMatcher := regexp.MustCompile(currencyPattern)
return func(given ledger.Balances, delta time.Duration) ledger.Balances {
result := maps.Clone(given)
for k, v := range result {
result[k] = maps.Clone(v)
}
for name := range result {
if !nameMatcher.MatchString(name) {
continue
}
for currency := range result[name] {
if !currencyMatcher.MatchString(string(currency)) {
continue
}
percentOfYearPassed := float64(delta) / float64(time.Hour*365)
result[name][currency] *= math.Pow(1.0+apy/12.0, percentOfYearPassed)
}
}
return result
}
}