From 1e06ca91fe574833a2f463a8e4c6b4738fd03f2a Mon Sep 17 00:00:00 2001
From: Sujan Poudel <mail@sujanpoudel.me>
Date: Thu, 4 Jan 2024 08:11:25 +0545
Subject: [PATCH] forex country info (#49)

---
 .../sujanpoudel/playdeals/domain/ForexRate.kt |  8 +++++-
 .../playdeals/jobs/ForexFetcher.kt            | 24 +++++++++++++++-
 .../playdeals/api/forex/GetForexApiTest.kt    | 28 +++++++++++++++++--
 3 files changed, 56 insertions(+), 4 deletions(-)

diff --git a/backend/src/main/kotlin/me/sujanpoudel/playdeals/domain/ForexRate.kt b/backend/src/main/kotlin/me/sujanpoudel/playdeals/domain/ForexRate.kt
index 286e35f..f47a190 100644
--- a/backend/src/main/kotlin/me/sujanpoudel/playdeals/domain/ForexRate.kt
+++ b/backend/src/main/kotlin/me/sujanpoudel/playdeals/domain/ForexRate.kt
@@ -8,4 +8,10 @@ data class ForexRate(
   val rates: List<ConversionRate>
 )
 
-data class ConversionRate(val currency: String, val rate: Float)
+data class ConversionRate(
+  val currency: String,
+  val symbol: String,
+  val name: String,
+  val flag: String,
+  val rate: Float
+)
diff --git a/backend/src/main/kotlin/me/sujanpoudel/playdeals/jobs/ForexFetcher.kt b/backend/src/main/kotlin/me/sujanpoudel/playdeals/jobs/ForexFetcher.kt
index 5d87dd3..a16d17e 100644
--- a/backend/src/main/kotlin/me/sujanpoudel/playdeals/jobs/ForexFetcher.kt
+++ b/backend/src/main/kotlin/me/sujanpoudel/playdeals/jobs/ForexFetcher.kt
@@ -19,6 +19,8 @@ import org.kodein.di.instance
 import java.time.Duration
 import java.time.OffsetDateTime
 import java.time.ZoneOffset
+import java.util.Currency
+import java.util.Locale
 import java.util.UUID
 
 class ForexFetcher(
@@ -57,10 +59,23 @@ class ForexFetcher(
     val epochSeconds = response.getLong("timestamp")
     val usdRate = response.getJsonObject("rates").getNumber("USD").toFloat()
 
+    val currencyLocale = Locale.getAvailableLocales().associateBy {
+      kotlin.runCatching { Currency.getInstance(it) }.getOrNull() ?: Locale.getDefault()
+    }
+
     return ForexRate(
       timestamp = OffsetDateTime.ofInstant(java.time.Instant.ofEpochSecond(epochSeconds), ZoneOffset.UTC),
       rates = response.getJsonObject("rates").map {
-        ConversionRate(it.key, (it.value as Number).toFloat() / usdRate)
+        val currency = kotlin.runCatching { Currency.getInstance(it.key) }.getOrNull()
+        val locale = currencyLocale.getOrDefault(currency, Locale.US)
+
+        ConversionRate(
+          currency = it.key,
+          symbol = currency?.getSymbol(locale) ?: "$",
+          name = currency?.displayName ?: it.key,
+          flag = locale.flagEmoji,
+          rate = (it.value as Number).toFloat() / usdRate
+        )
       }
     )
   }
@@ -89,3 +104,10 @@ suspend fun KeyValuesRepository.getForexRate(): ForexRate? = get(KEY_FOREX_RATE)
 }
 
 suspend fun KeyValuesRepository.saveForexRate(forexRate: ForexRate) = set(KEY_FOREX_RATE, Json.encode(forexRate))
+
+private val Locale.flagEmoji: String
+  get() {
+    val firstLetter = Character.codePointAt(country, 0) - 0x41 + 0x1F1E6
+    val secondLetter = Character.codePointAt(country, 1) - 0x41 + 0x1F1E6
+    return String(Character.toChars(firstLetter)) + String(Character.toChars(secondLetter))
+  }
diff --git a/backend/src/test/kotlin/me/sujanpoudel/playdeals/api/forex/GetForexApiTest.kt b/backend/src/test/kotlin/me/sujanpoudel/playdeals/api/forex/GetForexApiTest.kt
index 5b40a58..4711820 100644
--- a/backend/src/test/kotlin/me/sujanpoudel/playdeals/api/forex/GetForexApiTest.kt
+++ b/backend/src/test/kotlin/me/sujanpoudel/playdeals/api/forex/GetForexApiTest.kt
@@ -8,17 +8,38 @@ import me.sujanpoudel.playdeals.IntegrationTest
 import me.sujanpoudel.playdeals.domain.ConversionRate
 import me.sujanpoudel.playdeals.domain.ForexRate
 import me.sujanpoudel.playdeals.get
+import me.sujanpoudel.playdeals.jobs.getForexRate
 import me.sujanpoudel.playdeals.jobs.saveForexRate
 import me.sujanpoudel.playdeals.repositories.KeyValuesRepository
 import org.junit.jupiter.api.Test
 import java.time.OffsetDateTime
+import java.time.ZoneOffset
 
 class GetForexApiTest(vertx: Vertx) : IntegrationTest(vertx) {
+
+  @Test
+  fun `Key value repo should properly store the forex rate`() = runTest {
+    val repository = di.get<KeyValuesRepository>()
+
+    val forexRate = ForexRate(
+      timestamp = OffsetDateTime.now().withOffsetSameInstant(ZoneOffset.UTC),
+      rates = listOf(ConversionRate("USD", "$", "US Dollar", "🇺🇸", 1.1f))
+    )
+    repository.saveForexRate(forexRate)
+
+    val savedForexRate = repository.getForexRate()
+
+    savedForexRate shouldBe forexRate
+  }
+
   @Test
   fun `should return forex if there is data`() = runTest {
     val repository = di.get<KeyValuesRepository>()
 
-    val forexRate = ForexRate(OffsetDateTime.now(), listOf(ConversionRate("USD", 1.1f)))
+    val forexRate = ForexRate(
+      timestamp = OffsetDateTime.now().withOffsetSameInstant(ZoneOffset.UTC),
+      rates = listOf(ConversionRate("USD", "$", "US Dollar", "🇺🇸", 1.1f))
+    )
 
     repository.saveForexRate(forexRate)
 
@@ -28,11 +49,14 @@ class GetForexApiTest(vertx: Vertx) : IntegrationTest(vertx) {
       .bodyAsJsonObject()
 
     response.getJsonObject("data").also { data ->
-      OffsetDateTime.parse(data.getString("timestamp")).toEpochSecond() shouldBe forexRate.timestamp.toEpochSecond()
+      OffsetDateTime.parse(data.getString("timestamp")) shouldBe forexRate.timestamp
       data.getJsonArray("rates").also { rates ->
         rates.size() shouldBe 1
         (rates.first() as JsonObject).also { rate ->
           rate.getString("currency") shouldBe "USD"
+          rate.getString("symbol") shouldBe "$"
+          rate.getString("name") shouldBe "US Dollar"
+          rate.getString("flag") shouldBe "🇺🇸"
           rate.getFloat("rate") shouldBe 1.1f
         }
       }