[AN/USER] feat: 축제 목록 화면 페이징 작업(#673) (#724)

* feat(FakeFestivalRepository): 가짜 축제 저장소를 필터링 작업에 용이하게 변경

* feat(FestivalFilterUiState): FestivalFilterUiState 는 tabPosition 을 가진다

* feat(FestivalTabUiState): selected 람다에 포지션이 아닌 FestivalFilterUiState 를 넘긴다

* feat(FakeFestivalRepository): 가짜 축제 저장소는 예정된 축제를 반환할 수 있다

* feat(FestivalListViewModel): 같은 필터가 아니면 축제 목록을 변경한다

* feat(FestivalListMoreItemViewHolder): more item 프로그래스바 뷰 아이템 생성

* feat(FestivalListAdapter): 축제 목록에 더보기 아이템 추가

* feat(FestivalListAdapter): isLast 가 false 일때만 더보기를 추가한다.

* feat(FestivalListViewModel): 현재 축제 목록 불러오기 함수 분리

* feat(FestivalList): Success State recyclerView get items 로직 병합

* feat(FestivalListViewModel): 축제 목록 초기화와 축제 목록 추가 로드를 분리한다

android/festago/data/src/main/java/com/festago/festago/data/repository/FakeFestivalRepository.kt

@@ -14,7 +14,12 @@ import javax.inject.Inject
 class FakeFestivalRepository @Inject constructor() : FestivalRepository {
 
     override suspend fun loadPopularFestivals(): Result<PopularFestivals> {
-        return Result.success(PopularFestivals("인기 축제 목록", FakeFestivals.popularFestivals))
+        return Result.success(
+            PopularFestivals(
+                title = "인기 축제 목록",
+                festivals = FakeFestivals.popularFestivals,
+            ),
+        )
     }
 
     override suspend fun loadFestivals(
@@ -27,18 +32,24 @@ class FakeFestivalRepository @Inject constructor() : FestivalRepository {
         val notNullSize = size ?: DEFAULT_SIZE
         val notNullLastFestivalId = lastFestivalId ?: DEFAULT_LAST_FESTIVAL_ID
 
+        if (festivalFilter == FestivalFilter.PLANNED) {
+            return Result.success(
+                FestivalsPage(isLastPage = true, festivals = FakeFestivals.plannedFestivals),
+            )
+        }
+
         if (notNullLastFestivalId + notNullSize < LAST_ITEM_ID) {
             return Result.success(
                 FestivalsPage(
-                    false,
-                    getFestivals((notNullLastFestivalId + 1)..(notNullLastFestivalId + notNullSize)),
+                    isLastPage = false,
+                    festivals = getFestivals((notNullLastFestivalId + 1)..(notNullLastFestivalId + notNullSize)),
                 ),
             )
         }
         return Result.success(
             FestivalsPage(
-                true,
-                getFestivals((notNullLastFestivalId + 1)..LAST_ITEM_ID),
+                isLastPage = true,
+                festivals = getFestivals((notNullLastFestivalId + 1)..LAST_ITEM_ID),
             ),
         )
     }

android/festago/data/src/main/java/com/festago/festago/data/repository/FakeFestivals.kt

@@ -127,7 +127,7 @@ object FakeFestivals {
 
     val plannedFestivals = listOf(
         Festival(
-            id = 1,
+            id = 30,
             name = "뉴진스 콘서트",
             startDate = LocalDate.now().plusDays(1L),
             endDate = LocalDate.MAX,
@@ -142,7 +142,7 @@ object FakeFestivals {
             ),
         ),
         Festival(
-            id = 2,
+            id = 31,
             name = "아이브 콘서트",
             startDate = LocalDate.now().plusDays(3L),
             endDate = LocalDate.MAX,
@@ -177,7 +177,7 @@ object FakeFestivals {
             ),
         ),
         Festival(
-            id = 3,
+            id = 32,
             name = "아이들 콘서트",
             startDate = LocalDate.now().plusDays(5L),
             endDate = LocalDate.MAX,
@@ -192,7 +192,7 @@ object FakeFestivals {
             ),
         ),
         Festival(
-            id = 4,
+            id = 33,
             name = "뉴진스 콘서트",
             startDate = LocalDate.now().plusDays(20L),
             endDate = LocalDate.MAX,
@@ -207,7 +207,7 @@ object FakeFestivals {
             ),
         ),
         Festival(
-            id = 5,
+            id = 34,
             name = "아이브 콘서트",
             startDate = LocalDate.now().plusDays(40L),
             endDate = LocalDate.MAX,

android/festago/presentation/src/main/java/com/festago/festago/presentation/ui/home/festivallist/FestivalListFragment.kt

@@ -12,13 +12,14 @@ import androidx.fragment.app.Fragment
 import androidx.fragment.app.FragmentTransaction
 import androidx.fragment.app.commit
 import androidx.fragment.app.viewModels
+import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import com.festago.festago.presentation.R
 import com.festago.festago.presentation.databinding.FragmentFestivalListBinding
 import com.festago.festago.presentation.ui.artistdetail.ArtistDetailFragment
 import com.festago.festago.presentation.ui.home.festivallist.festival.FestivalListAdapter
-import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalFilterUiState
 import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalListUiState
+import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalMoreItemUiState
 import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalTabUiState
 import com.festago.festago.presentation.ui.schooldetail.SchoolDetailFragment
 import com.festago.festago.presentation.util.repeatOnStarted
@@ -66,15 +67,15 @@ class FestivalListFragment : Fragment() {
     }
 
     private fun initView() {
-        vm.loadFestivals()
+        vm.initFestivalList()
         initViewPager()
         initRecyclerView()
         initRefresh()
     }
 
     private fun initRefresh() {
         binding.srlFestivalList.setOnRefreshListener {
-            vm.loadFestivals()
+            vm.initFestivalList()
             binding.srlFestivalList.isRefreshing = false
         }
         binding.ivSearch.setOnClickListener { // 임시 연결
@@ -97,6 +98,30 @@ class FestivalListFragment : Fragment() {
     }
 
     private fun initRecyclerView() {
+        initScrollEvent()
+        initDecoration()
+    }
+
+    private fun initScrollEvent() {
+        binding.rvFestivalList.addOnScrollListener(object : RecyclerView.OnScrollListener() {
+            override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
+                super.onScrolled(recyclerView, dx, dy)
+
+                val festivalListUiState = vm.uiState.value as? FestivalListUiState.Success ?: return
+                if (festivalListUiState.isLastPage) return
+
+                val lastVisibleItemPosition =
+                    (recyclerView.layoutManager as LinearLayoutManager?)!!.findLastCompletelyVisibleItemPosition()
+
+                val itemTotalCount = recyclerView.adapter!!.itemCount - 1
+                if (lastVisibleItemPosition == itemTotalCount) {
+                    vm.loadFestivals()
+                }
+            }
+        })
+    }
+
+    private fun initDecoration() {
         binding.rvFestivalList.addItemDecoration(object : RecyclerView.ItemDecoration() {
             override fun getItemOffsets(
                 outRect: Rect,
@@ -135,22 +160,14 @@ class FestivalListFragment : Fragment() {
     }
 
     private fun FestivalListUiState.Success.getItems(): List<Any> {
-        val items = mutableListOf<Any>()
-        if (popularFestivalUiState.festivals.isNotEmpty()) {
-            items.add(popularFestivalUiState)
-        }
-        items.add(
-            FestivalTabUiState {
-                val festivalFilter = when (it) {
-                    0 -> FestivalFilterUiState.PROGRESS
-                    1 -> FestivalFilterUiState.PLANNED
-                    else -> FestivalFilterUiState.PROGRESS
-                }
-                vm.loadFestivals(festivalFilter)
-            },
-        )
-        items.addAll(festivals)
-        return items.toList()
+        return mutableListOf<Any>().apply {
+            if (popularFestivalUiState.festivals.isNotEmpty()) {
+                add(popularFestivalUiState)
+            }
+            add(FestivalTabUiState(festivalFilter) { vm.loadFestivals(it) })
+            addAll(festivals)
+            if (!isLastPage) add(FestivalMoreItemUiState)
+        }.toList()
     }
 
     private fun showSchoolDetail() {

android/festago/presentation/src/main/java/com/festago/festago/presentation/ui/home/festivallist/FestivalListViewModel.kt

@@ -32,16 +32,12 @@ class FestivalListViewModel @Inject constructor(
 
     private var festivalFilter: FestivalFilter = FestivalFilter.PROGRESS
 
-    fun loadFestivals(festivalFilterUiState: FestivalFilterUiState? = null) {
+    fun initFestivalList() {
         viewModelScope.launch {
-            if (festivalFilterUiState != null) {
-                festivalFilter = festivalFilterUiState.toDomain()
-            }
-
             val deferredPopularFestivals = async { festivalRepository.loadPopularFestivals() }
-            val deferredFestivals =
-                async { festivalRepository.loadFestivals(festivalFilter = festivalFilter) }
-
+            val deferredFestivals = async {
+                festivalRepository.loadFestivals(festivalFilter = festivalFilter)
+            }
             runCatching {
                 val festivalsPage = deferredFestivals.await().getOrThrow()
                 val popularFestivals = deferredPopularFestivals.await().getOrThrow()
@@ -52,6 +48,7 @@ class FestivalListViewModel @Inject constructor(
                         festivals = popularFestivals.festivals.map { it.toUiState() },
                     ),
                     festivals = festivalsPage.festivals.map { it.toUiState() },
+                    festivalFilter = festivalFilter.toUiState(),
                     isLastPage = festivalsPage.isLastPage,
                 )
             }.onFailure {
@@ -64,11 +61,51 @@ class FestivalListViewModel @Inject constructor(
         }
     }
 
+    fun loadFestivals(festivalFilterUiState: FestivalFilterUiState? = null) {
+        val successUiState = uiState.value as? FestivalListUiState.Success ?: return
+
+        viewModelScope.launch {
+            val currentFestivals = getCurrentFestivals(festivalFilterUiState)
+
+            festivalRepository.loadFestivals(
+                festivalFilter = festivalFilter,
+                lastFestivalId = currentFestivals.lastOrNull()?.id,
+                lastStartDate = currentFestivals.lastOrNull()?.startDate,
+            ).onSuccess { festivalsPage ->
+                _uiState.value = FestivalListUiState.Success(
+                    PopularFestivalUiState(
+                        title = successUiState.popularFestivalUiState.title,
+                        festivals = successUiState.popularFestivalUiState.festivals,
+                    ),
+                    festivals = currentFestivals + festivalsPage.festivals.map { it.toUiState() },
+                    festivalFilter = festivalFilter.toUiState(),
+                    isLastPage = festivalsPage.isLastPage,
+                )
+            }
+        }
+    }
+
+    private fun getCurrentFestivals(festivalFilterUiState: FestivalFilterUiState?): List<FestivalItemUiState> {
+        var festivals = (uiState.value as? FestivalListUiState.Success)?.festivals ?: listOf()
+
+        if (festivalFilterUiState != null && festivalFilter != festivalFilterUiState.toDomain()) {
+            festivalFilter = festivalFilterUiState.toDomain()
+            festivals = listOf()
+        }
+        return festivals
+    }
+
     private fun FestivalFilterUiState.toDomain() = when (this) {
         FestivalFilterUiState.PLANNED -> FestivalFilter.PLANNED
         FestivalFilterUiState.PROGRESS -> FestivalFilter.PROGRESS
     }
 
+    private fun FestivalFilter.toUiState() = when (this) {
+        FestivalFilter.PLANNED -> FestivalFilterUiState.PLANNED
+        FestivalFilter.PROGRESS -> FestivalFilterUiState.PROGRESS
+        else -> FestivalFilterUiState.PLANNED
+    }
+
     private fun Festival.toUiState() = FestivalItemUiState(
         id = id,
         name = name,

android/festago/presentation/src/main/java/com/festago/festago/presentation/ui/home/festivallist/festival/FestivalListAdapter.kt

@@ -4,6 +4,7 @@ import android.view.ViewGroup
 import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.ListAdapter
 import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalItemUiState
+import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalMoreItemUiState
 import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalTabUiState
 import com.festago.festago.presentation.ui.home.festivallist.uistate.PopularFestivalUiState
 
@@ -16,6 +17,7 @@ class FestivalListAdapter(
             1 -> FestivalListPopularViewHolder.of(parent)
             2 -> FestivalListFestivalViewHolder.of(parent, onArtistClick)
             3 -> FestivalListTabViewHolder.of(parent)
+            4 -> FestivalListMoreItemViewHolder.of(parent)
             else -> throw IllegalArgumentException("Invalid viewType")
         }
     }
@@ -26,6 +28,7 @@ class FestivalListAdapter(
             is FestivalListPopularViewHolder -> holder.bind(item as PopularFestivalUiState)
             is FestivalListFestivalViewHolder -> holder.bind(item as FestivalItemUiState)
             is FestivalListTabViewHolder -> holder.bind(item as FestivalTabUiState)
+            is FestivalListMoreItemViewHolder -> holder.bind(item as FestivalMoreItemUiState)
         }
     }
 
@@ -34,6 +37,7 @@ class FestivalListAdapter(
             is PopularFestivalUiState -> 1
             is FestivalItemUiState -> 2
             is FestivalTabUiState -> 3
+            is FestivalMoreItemUiState -> 4
             else -> throw IllegalArgumentException("Invalid item")
         }
     }
@@ -44,6 +48,7 @@ class FestivalListAdapter(
                 oldItem is PopularFestivalUiState && newItem is PopularFestivalUiState -> true
                 oldItem is FestivalItemUiState && newItem is FestivalItemUiState -> oldItem.id == newItem.id
                 oldItem is FestivalTabUiState && newItem is FestivalTabUiState -> true
+                oldItem is FestivalMoreItemUiState && newItem is FestivalMoreItemUiState -> true
                 else -> false
             }
 
@@ -54,8 +59,9 @@ class FestivalListAdapter(
                 oldItem is FestivalItemUiState && newItem is FestivalItemUiState
                 -> oldItem as FestivalItemUiState == newItem
 
-                oldItem is FestivalTabUiState && newItem is FestivalTabUiState
-                -> true
+                oldItem is FestivalTabUiState && newItem is FestivalTabUiState -> true
+
+                oldItem is FestivalMoreItemUiState && newItem is FestivalMoreItemUiState -> true
 
                 else -> false
             }

android/festago/presentation/src/main/java/com/festago/festago/presentation/ui/home/festivallist/festival/FestivalListMoreItemViewHolder.kt

@@ -0,0 +1,24 @@
+package com.festago.festago.presentation.ui.home.festivallist.festival
+
+import android.view.LayoutInflater
+import android.view.ViewGroup
+import com.festago.festago.presentation.databinding.ItemFestivalListMoreItemBinding
+import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalMoreItemUiState
+
+class FestivalListMoreItemViewHolder(val binding: ItemFestivalListMoreItemBinding) :
+    FestivalListViewHolder(binding) {
+
+    fun bind(festivalMoreItemUiState: FestivalMoreItemUiState) {
+    }
+
+    companion object {
+        fun of(parent: ViewGroup): FestivalListMoreItemViewHolder {
+            val binding = ItemFestivalListMoreItemBinding.inflate(
+                LayoutInflater.from(parent.context),
+                parent,
+                false,
+            )
+            return FestivalListMoreItemViewHolder(binding)
+        }
+    }
+}

android/festago/presentation/src/main/java/com/festago/festago/presentation/ui/home/festivallist/festival/FestivalListTabViewHolder.kt

@@ -4,6 +4,7 @@ import android.view.LayoutInflater
 import android.view.ViewGroup
 import com.festago.festago.presentation.R
 import com.festago.festago.presentation.databinding.ItemFestivalListTabBinding
+import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalFilterUiState
 import com.festago.festago.presentation.ui.home.festivallist.uistate.FestivalTabUiState
 import com.google.android.material.tabs.TabLayout
 
@@ -23,19 +24,26 @@ class FestivalListTabViewHolder(val binding: ItemFestivalListTabBinding) :
     }
 
     fun bind(festivalTabUiState: FestivalTabUiState) {
-        binding.tlFestivalListTab.clearOnTabSelectedListeners()
-        binding.tlFestivalListTab.addOnTabSelectedListener(
-            object : TabLayout.OnTabSelectedListener {
-                override fun onTabSelected(tab: TabLayout.Tab) {
-                    festivalTabUiState.onClick(tab.position)
-                }
+        with(binding.tlFestivalListTab) {
+            clearOnTabSelectedListeners()
+            selectTab(getTabAt(festivalTabUiState.selectedFilter.tabPosition))
+            addOnTabSelectedListener(
+                object : TabLayout.OnTabSelectedListener {
+                    override fun onTabSelected(tab: TabLayout.Tab) {
+                        festivalTabUiState.onFilterSelected(getFestivalFilterAt(tab.position))
+                    }
 
-                override fun onTabUnselected(tab: TabLayout.Tab) = Unit
-                override fun onTabReselected(tab: TabLayout.Tab) = Unit
-            },
-        )
+                    override fun onTabUnselected(tab: TabLayout.Tab) = Unit
+                    override fun onTabReselected(tab: TabLayout.Tab) = Unit
+                },
+            )
+        }
     }
 
+    private fun getFestivalFilterAt(position: Int): FestivalFilterUiState =
+        FestivalFilterUiState.values().find { it.tabPosition == position }
+            ?: FestivalFilterUiState.PROGRESS
+
     companion object {
         fun of(parent: ViewGroup): FestivalListTabViewHolder {
             val binding = ItemFestivalListTabBinding.inflate(

android/festago/presentation/src/main/java/com/festago/festago/presentation/ui/home/festivallist/uistate/FestivalFilterUiState.kt

@@ -1,5 +1,5 @@
 package com.festago.festago.presentation.ui.home.festivallist.uistate
 
-enum class FestivalFilterUiState {
-    PROGRESS, PLANNED
+enum class FestivalFilterUiState(val tabPosition: Int) {
+    PROGRESS(0), PLANNED(1)
 }