From 02f85f808db8bc74923fb147ab569587fb7f3f45 Mon Sep 17 00:00:00 2001
From: klaus <klaus@vividnext.co.kr>
Date: Wed, 27 May 2026 22:27:40 +0900
Subject: [PATCH] =?UTF-8?q?feat(banner):=20=EB=B0=B0=EB=84=88=20=EC=B9=B4?=
 =?UTF-8?q?=EC=9A=B4=ED=84=B0=EC=99=80=20=EC=83=81=ED=83=9C=20=EA=B3=84?=
 =?UTF-8?q?=EC=95=BD=EC=9D=84=20=EC=B6=94=EA=B0=80=ED=95=9C=EB=8B=A4?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../widget/banner/BannerCounterFormatter.kt   |  7 +++
 .../sodalive/v2/widget/banner/BannerState.kt  | 33 +++++++++++++
 .../banner/BannerCounterFormatterTest.kt      | 28 +++++++++++
 .../v2/widget/banner/BannerStateTest.kt       | 49 +++++++++++++++++++
 4 files changed, 117 insertions(+)
 create mode 100644 app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatter.kt
 create mode 100644 app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerState.kt
 create mode 100644 app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatterTest.kt
 create mode 100644 app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerStateTest.kt

diff --git a/app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatter.kt b/app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatter.kt
new file mode 100644
index 00000000..fa943267
--- /dev/null
+++ b/app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatter.kt
@@ -0,0 +1,7 @@
+package kr.co.vividnext.sodalive.v2.widget.banner
+
+object BannerCounterFormatter {
+    fun format(currentIndex: Int, count: Int): String {
+        return "%02d / %02d".format(currentIndex + 1, count)
+    }
+}
diff --git a/app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerState.kt b/app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerState.kt
new file mode 100644
index 00000000..f11a1706
--- /dev/null
+++ b/app/src/main/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerState.kt
@@ -0,0 +1,33 @@
+package kr.co.vividnext.sodalive.v2.widget.banner
+
+data class BannerState(
+    val displayMode: BannerDisplayMode,
+    val currentIndex: Int,
+    private val count: Int
+) {
+    fun nextIndex(): Int = (currentIndex + 1) % count
+
+    fun previousIndex(): Int = (currentIndex - 1 + count) % count
+
+    companion object {
+        fun from(count: Int, currentIndex: Int): BannerState {
+            val displayMode = when (count) {
+                0 -> BannerDisplayMode.Hidden
+                1 -> BannerDisplayMode.Single
+                else -> BannerDisplayMode.Carousel
+            }
+            val correctedIndex = if (currentIndex in 0 until count) currentIndex else 0
+            return BannerState(
+                displayMode = displayMode,
+                currentIndex = correctedIndex,
+                count = count
+            )
+        }
+    }
+}
+
+enum class BannerDisplayMode {
+    Hidden,
+    Single,
+    Carousel
+}
diff --git a/app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatterTest.kt b/app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatterTest.kt
new file mode 100644
index 00000000..c9f8929e
--- /dev/null
+++ b/app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerCounterFormatterTest.kt
@@ -0,0 +1,28 @@
+package kr.co.vividnext.sodalive.v2.widget.banner
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class BannerCounterFormatterTest {
+
+    @Test
+    fun `20개 배너의 첫 번째 아이템은 1부터 시작하는 카운터로 표시한다`() {
+        val text = BannerCounterFormatter.format(currentIndex = 0, count = 20)
+
+        assertEquals("01 / 20", text)
+    }
+
+    @Test
+    fun `20개 배너의 열 번째 아이템은 1부터 시작하는 카운터로 표시한다`() {
+        val text = BannerCounterFormatter.format(currentIndex = 9, count = 20)
+
+        assertEquals("10 / 20", text)
+    }
+
+    @Test
+    fun `1개 배너도 formatter는 양쪽을 두 자리로 표시한다`() {
+        val text = BannerCounterFormatter.format(currentIndex = 0, count = 1)
+
+        assertEquals("01 / 01", text)
+    }
+}
diff --git a/app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerStateTest.kt b/app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerStateTest.kt
new file mode 100644
index 00000000..8ea50457
--- /dev/null
+++ b/app/src/test/java/kr/co/vividnext/sodalive/v2/widget/banner/BannerStateTest.kt
@@ -0,0 +1,49 @@
+package kr.co.vividnext.sodalive.v2.widget.banner
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class BannerStateTest {
+
+    @Test
+    fun `배너 개수가 0이면 숨김 모드다`() {
+        val state = BannerState.from(count = 0, currentIndex = 0)
+
+        assertEquals(BannerDisplayMode.Hidden, state.displayMode)
+    }
+
+    @Test
+    fun `배너 개수가 1이면 단일 모드다`() {
+        val state = BannerState.from(count = 1, currentIndex = 0)
+
+        assertEquals(BannerDisplayMode.Single, state.displayMode)
+    }
+
+    @Test
+    fun `배너 개수가 2이면 캐러셀 모드다`() {
+        val state = BannerState.from(count = 2, currentIndex = 0)
+
+        assertEquals(BannerDisplayMode.Carousel, state.displayMode)
+    }
+
+    @Test
+    fun `마지막 배너의 다음 index는 첫 번째로 순환한다`() {
+        val state = BannerState.from(count = 3, currentIndex = 2)
+
+        assertEquals(0, state.nextIndex())
+    }
+
+    @Test
+    fun `첫 번째 배너의 이전 index는 마지막으로 순환한다`() {
+        val state = BannerState.from(count = 3, currentIndex = 0)
+
+        assertEquals(2, state.previousIndex())
+    }
+
+    @Test
+    fun `현재 index가 범위를 벗어나면 첫 번째로 보정한다`() {
+        val state = BannerState.from(count = 3, currentIndex = 3)
+
+        assertEquals(0, state.currentIndex)
+    }
+}