demo-money-project/src/main/kotlin/com/example/demo/domain/MoneyDyn.kt

package com.example.demo.domain

class MoneyDyn(
    var value: Double = 0.0,
    var currency: String = "USD"
) {

    fun addMoney(other: MoneyDyn): MoneyDyn {
        this.value = this.value.plus(exchange(other, this.currency))
        return this
    }

    fun exchange(fromMoney: MoneyDyn, exchangeCurrency: String): Double {
        if (!fromMoney.currency.equals(exchangeCurrency, ignoreCase = true)) {
            val rateFrom = MoneyConfig.getRate(fromMoney.currency)
            val rateTo = MoneyConfig.getRate(exchangeCurrency)
            return computeRate(amountFrom = fromMoney.value, rateFrom = rateFrom, rateTo = rateTo)
        }
        return fromMoney.value
    }

    fun exchangeTo(toCurrency: String): MoneyDyn {
        return MoneyDyn(value = exchange(this, toCurrency))
    }

    private fun computeRate(
        amountFrom: Double = 1.0,
        baseRate: Double = 1.0,
        rateFrom: Double,
        rateTo: Double
    ): Double {
        return amountFrom * ((baseRate / rateFrom) / (baseRate / rateTo))
    }

    private fun isEqualCurrency(other: MoneyDyn) =
        this.currency.equals(other.currency, ignoreCase = true)

    override fun toString(): String {
        return "MoneyDyn(value=$value, currency='$currency')"
    }
}