[Step2] 로또(자동)

README.md

@@ -15,4 +15,18 @@
 - [x] indent는 depth가 2를 넘지 않도록 구현
   - ex) while 문 안에 if 문이 있으면 들여쓰기는 2이다
 - [x] 함수의 길이가 10개 Line을 넘어가지 않도록 구현
-  - 함수가 한 가지 일만 잘 하도록 구현
+  - 함수가 한 가지 일만 잘 하도록 구현
+
+
+
+## 로또(자동)
+### 기능 요구 사항
+- [x] 구입한 금액에 해당하는 구매 갯수 반환
+- [x] 로또 구입 금액을 입력하면 구입 금액에 해당하는 로또를 발급해야 한다
+
+### 프로그래밍 요구 사항
+- [x] InputView 생성
+- [x] indent는 depth가 2를 넘지 않도록 구현
+- [x] 함수의 길이가 15 라인을 넘어가지 않도록 구현
+- [x] ResultView 생성
+

src/main/kotlin/lotto/InputView.kt

@@ -0,0 +1,20 @@
+package lotto
+
+object InputView {
+
+    fun requestPurchaseAmount(): Int {
+        printMessage("구입금액을 입력해 주세요.")
+        return readln().toInt()
+    }
+
+    fun requestLastWinnerNumbers(): List<Int> {
+        printMessage("\n지난 주 당첨 번호를 입력해 주세요.")
+        return readln().split(",").map {
+            it.trim().toInt()
+        }
+    }
+
+    private fun printMessage(message: String) {
+        println(message)
+    }
+}

src/main/kotlin/lotto/Lottery.kt

@@ -0,0 +1,5 @@
+package lotto
+
+data class Lottery(
+    val numbers: List<Int>
+)

src/main/kotlin/lotto/LotteryResult.kt

@@ -0,0 +1,7 @@
+package lotto
+
+data class LotteryResult(
+    val prize: Int,
+    val matchCount: Int,
+    val message: String
+)

src/main/kotlin/lotto/LotteryShop.kt

@@ -0,0 +1,21 @@
+package lotto
+
+class LotteryShop {
+
+    fun buy(money: Int): UserLottery {
+        val count = money / LOTTERY_PRICE
+        val lotteryTickets = mutableListOf<Lottery>()
+        repeat(count) {
+            lotteryTickets.add(
+                Lottery((MIN_LOTTERY_NUMBER..MAX_LOTTERY_NUMBER).shuffled().take(6).sorted())
+            )
+        }
+        return UserLottery(count, lotteryTickets)
+    }
+
+    companion object {
+        private const val LOTTERY_PRICE = 1000
+        private const val MIN_LOTTERY_NUMBER = 1
+        private const val MAX_LOTTERY_NUMBER = 45
+    }
+}

src/main/kotlin/lotto/LotteryStatistic.kt

@@ -0,0 +1,36 @@
+package lotto
+
+object LotteryStatistic {
+
+    fun getWinStatistic(
+        lotteryTickets: List<Lottery>,
+        lastWinnerNumbers: List<Int>
+    ): Pair<List<LotteryResult>, Double> {
+        val winResult = checkLotteryTickets(lotteryTickets, lastWinnerNumbers)
+
+        val lotteryResults = mutableListOf<LotteryResult>()
+        var sum = 0
+        winResult.forEach { (count, matchCount) ->
+            val prize = WinnerPrize.getPrize(count).money
+            val message = "${count}개 일치 (${prize}원) - ${matchCount}개"
+            lotteryResults.add(LotteryResult(prize, matchCount, message))
+            sum += (prize * matchCount)
+        }
+
+        return lotteryResults.toList() to sum.toDouble()
+    }
+
+    private fun checkLotteryTickets(
+        lotteryTickets: List<Lottery>,
+        lastWinnerNumbers: List<Int>
+    ): List<Pair<Int, Int>> =
+        lotteryTickets.map { lottery ->
+            lottery.numbers.intersect(
+                lastWinnerNumbers.sorted().toSet()
+            ).count()
+        }.filter { it >= 3 }
+            .groupingBy { it }
+            .eachCount()
+            .toList()
+            .sortedBy { it.first }
+}

src/main/kotlin/lotto/Main.kt

@@ -0,0 +1,15 @@
+package lotto
+
+fun main() {
+    val lotteryShop = LotteryShop()
+    val money = InputView.requestPurchaseAmount()
+    val userLotteryInfo = lotteryShop.buy(money)
+
+    ResultView.printLotteryCount(userLotteryInfo.lotteryCount)
+    ResultView.printAllLotteries(userLotteryInfo.lotteryTickets)
+
+    val lastWinnerNumbers = InputView.requestLastWinnerNumbers()
+    val lotteryResults = LotteryStatistic.getWinStatistic(userLotteryInfo.lotteryTickets, lastWinnerNumbers)
+
+    ResultView.printWinStatistic(lotteryResults, money)
+}

src/main/kotlin/lotto/ResultView.kt

@@ -0,0 +1,25 @@
+package lotto
+
+object ResultView {
+
+    fun printLotteryCount(size: Int) {
+        println("${size}개를 구매했습니다.")
+    }
+
+    fun printAllLotteries(lotteryTickets: List<Lottery>) {
+        lotteryTickets.forEach { lottery ->
+            println(lottery.numbers)
+        }
+    }
+
+    fun printWinStatistic(
+        lotteryResults: Pair<List<LotteryResult>, Double>,
+        money: Int
+    ) {
+        println("\n당첨 통계\n-------------------")
+        lotteryResults.first.forEach { lotteryResult ->
+            println(lotteryResult.message)
+        }
+        println(String.format("총 수익률은 %.2f 입니다", lotteryResults.second / money))
+    }
+}

src/main/kotlin/lotto/UserLottery.kt

@@ -0,0 +1,6 @@
+package lotto
+
+data class UserLottery(
+    val lotteryCount: Int,
+    val lotteryTickets: List<Lottery>
+)

src/main/kotlin/lotto/WinnerPrize.kt

@@ -0,0 +1,18 @@
+package lotto
+
+enum class WinnerPrize(val money: Int) {
+
+    FIRST(2_000_000_000),
+    SECOND(1_500_000),
+    THIRD(50_000),
+    LAST(5_000);
+
+    companion object {
+        fun getPrize(sameCount: Int): WinnerPrize = when (sameCount) {
+            3 -> LAST
+            4 -> THIRD
+            5 -> SECOND
+            else -> FIRST
+        }
+    }
+}

src/test/kotlin/lotto/LotteryShopKoTest.kt

@@ -0,0 +1,53 @@
+package lotto
+
+import io.kotest.core.spec.style.StringSpec
+import io.kotest.inspectors.forAll
+import io.kotest.matchers.shouldBe
+
+class LotteryShopKoTest : StringSpec({
+
+    "구매한 금액에 해당하는 로또 갯수 반환" {
+        val lotteryShop = LotteryShop()
+        val actualInput = 14_000
+        lotteryShop.buy(actualInput).lotteryCount shouldBe 14
+    }
+
+    "일치하는 로또 갯수에 의한 당첨 금액" {
+        val first = WinnerPrize.getPrize(6)
+        val second = WinnerPrize.getPrize(5)
+        val third = WinnerPrize.getPrize(4)
+        val last = WinnerPrize.getPrize(3)
+
+        first.money shouldBe 2_000_000_000
+        second.money shouldBe 1_500_000
+        third.money shouldBe 50_000
+        last.money shouldBe 5_000
+    }
+
+    "구매한 로또들과 지난 주 당첨 번호가 일치하는지 확인" {
+        val lastWinnerNumbers = listOf(1, 2, 3, 4, 5, 6)
+        val lotteryTickets = listOf(
+            Lottery(listOf(1, 2, 3, 4, 39, 43)),
+            Lottery(listOf(9, 11, 21, 27, 28, 32)),
+            Lottery(listOf(4, 5, 14, 17, 31, 35)),
+            Lottery(listOf(11, 13, 17, 22, 25, 34)),
+            Lottery(listOf(1, 3, 5, 21, 41, 42)),
+            Lottery(listOf(6, 7, 17, 19, 32, 35)),
+            Lottery(listOf(2, 12, 19, 34, 35, 37)),
+            Lottery(listOf(1, 3, 5, 6, 39, 44)),
+            Lottery(listOf(2, 5, 8, 10, 13, 23)),
+            Lottery(listOf(7, 29, 30, 31, 34, 36))
+        )
+
+        val lotteryResults = LotteryStatistic.getWinStatistic(lotteryTickets, lastWinnerNumbers).first
+
+        lotteryResults.forEach {
+            when (it.prize) {
+                3 -> it.matchCount shouldBe 1
+                4 -> it.matchCount shouldBe 2
+                5 -> it.matchCount shouldBe 0
+                6 -> it.matchCount shouldBe 0
+            }
+        }
+    }
+})

src/test/kotlin/lotto/LotteryShopTest.kt

@@ -0,0 +1,56 @@
+package lotto
+
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+
+class LotteryShopTest {
+
+    @Test
+    fun `구매한 금액에 해당하는 로또 갯수 반환`() {
+        val lotteryShop = LotteryShop()
+        val actualInput = 14_000
+        val userLottery = lotteryShop.buy(actualInput)
+        assertThat(userLottery.lotteryCount).isEqualTo(14)
+    }
+
+    @Test
+    fun `일치하는 로또 갯수에 의한 당첨 금액`() {
+        val first = WinnerPrize.getPrize(6)
+        val second = WinnerPrize.getPrize(5)
+        val third = WinnerPrize.getPrize(4)
+        val last = WinnerPrize.getPrize(3)
+
+        assertThat(first.money).isEqualTo(2_000_000_000)
+        assertThat(second.money).isEqualTo(1_500_000)
+        assertThat(third.money).isEqualTo(50_000)
+        assertThat(last.money).isEqualTo(5_000)
+    }
+
+    @Test
+    fun `구매한 로또들과 지난 주 당첨 번호가 일치하는지 확인`() {
+        val lastWinnerNumbers = listOf(1, 2, 3, 4, 5, 6)
+        val lotteryTickets = listOf(
+            Lottery(listOf(1, 2, 3, 4, 39, 43)),
+            Lottery(listOf(9, 11, 21, 27, 28, 32)),
+            Lottery(listOf(4, 5, 14, 17, 31, 35)),
+            Lottery(listOf(11, 13, 17, 22, 25, 34)),
+            Lottery(listOf(1, 3, 5, 21, 41, 42)),
+            Lottery(listOf(6, 7, 17, 19, 32, 35)),
+            Lottery(listOf(2, 12, 19, 34, 35, 37)),
+            Lottery(listOf(1, 3, 5, 6, 39, 44)),
+            Lottery(listOf(2, 5, 8, 10, 13, 23)),
+            Lottery(listOf(7, 29, 30, 31, 34, 36))
+        )
+
+        val lotteryResults = LotteryStatistic.getWinStatistic(lotteryTickets, lastWinnerNumbers).first
+
+        lotteryResults.forEach {
+            when (it.prize) {
+                3 -> assertThat(it.matchCount).isEqualTo(1)
+                4 -> assertThat(it.matchCount).isEqualTo(2)
+                5 -> assertThat(it.matchCount).isEqualTo(0)
+                6 -> assertThat(it.matchCount).isEqualTo(0)
+            }
+        }
+    }
+}