For #6330 Collections Numbering (#6453)

* For #6330 - Added logic for getting the recommended default collection name

* For #6330 - Added unit test for default collection number method

app/src/main/java/org/mozilla/fenix/collections/CollectionCreationController.kt

@@ -69,6 +69,12 @@ class DefaultCollectionCreationController(
     private val sessionManager: SessionManager,
     private val lifecycleScope: CoroutineScope
 ) : CollectionCreationController {
+
+    companion object {
+        const val DEFAULT_INCREMENT_VALUE = 1
+        const val DEFAULT_COLLECTION_NUMBER_POSITION = 1
+    }
+
     override fun saveCollectionName(tabs: List<Tab>, name: String) {
         dismiss()
 
@@ -124,17 +130,40 @@ class DefaultCollectionCreationController(
     }
 
     override fun saveTabsToCollection(tabs: List<Tab>) {
-        store.dispatch(CollectionCreationAction.StepChanged(
+        store.dispatch(
-            saveCollectionStep = if (store.state.tabCollections.isEmpty()) {
+            CollectionCreationAction.StepChanged(
-                SaveCollectionStep.NameCollection
+                saveCollectionStep = if (store.state.tabCollections.isEmpty()) {
-            } else {
+                    SaveCollectionStep.NameCollection
-                SaveCollectionStep.SelectCollection
+                } else {
-            }
+                    SaveCollectionStep.SelectCollection
-        ))
+                },
+                defaultCollectionNumber = getDefaultCollectionNumber()
+            )
+        )
     }
 
     override fun addNewCollection() {
-        store.dispatch(CollectionCreationAction.StepChanged(SaveCollectionStep.NameCollection))
+        store.dispatch(
+            CollectionCreationAction.StepChanged(
+                SaveCollectionStep.NameCollection,
+                getDefaultCollectionNumber()
+            )
+        )
+    }
+
+    /**
+     * Returns the new default name recommendation for a collection
+     *
+     * Algorithm: Go through all collections, make a list of their names and keep only the default ones.
+     * Then get the numbers from all these default names, compute the maximum number and add one.
+     */
+    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    fun getDefaultCollectionNumber(): Int {
+        return (store.state.tabCollections
+            .map { it.title }
+            .filter { it.matches(Regex("Collection\\s\\d+")) }
+            .map { Integer.valueOf(it.split(" ")[DEFAULT_COLLECTION_NUMBER_POSITION]) }
+            .max() ?: 0) + DEFAULT_INCREMENT_VALUE
     }
 
     override fun addTabToSelection(tab: Tab) {

app/src/main/java/org/mozilla/fenix/collections/CollectionCreationStore.kt

@@ -40,7 +40,8 @@ data class CollectionCreationState(
     val selectedTabs: Set<Tab> = emptySet(),
     val saveCollectionStep: SaveCollectionStep = SaveCollectionStep.SelectTabs,
     val tabCollections: List<TabCollection> = emptyList(),
-    val selectedTabCollection: TabCollection? = null
+    val selectedTabCollection: TabCollection? = null,
+    val defaultCollectionNumber: Int = 1
 ) : State
 
 sealed class CollectionCreationAction : Action {
@@ -53,7 +54,10 @@ sealed class CollectionCreationAction : Action {
      *
      * This should be refactored, see kdoc on [SaveCollectionStep].
      */
-    data class StepChanged(val saveCollectionStep: SaveCollectionStep) : CollectionCreationAction()
+    data class StepChanged(
+        val saveCollectionStep: SaveCollectionStep,
+        val defaultCollectionNumber: Int = 1
+    ) : CollectionCreationAction()
 }
 
 private fun collectionCreationReducer(
@@ -64,5 +68,6 @@ private fun collectionCreationReducer(
     is CollectionCreationAction.RemoveAllTabs -> prevState.copy(selectedTabs = emptySet())
     is CollectionCreationAction.TabAdded -> prevState.copy(selectedTabs = prevState.selectedTabs + action.tab)
     is CollectionCreationAction.TabRemoved -> prevState.copy(selectedTabs = prevState.selectedTabs - action.tab)
-    is CollectionCreationAction.StepChanged -> prevState.copy(saveCollectionStep = action.saveCollectionStep)
+    is CollectionCreationAction.StepChanged -> prevState.copy(saveCollectionStep = action.saveCollectionStep,
+        defaultCollectionNumber = action.defaultCollectionNumber)
 }

app/src/main/java/org/mozilla/fenix/collections/CollectionCreationView.kt

@@ -252,7 +252,7 @@ class CollectionCreationView(
         name_collection_edittext.setText(
             view.context.getString(
                 R.string.create_collection_default_name,
-                state.tabCollections.size + 1
+                state.defaultCollectionNumber
             )
         )
         name_collection_edittext.setSelection(0, name_collection_edittext.text.length)

app/src/test/java/org/mozilla/fenix/collections/DefaultCollectionCreationControllerTest.kt

@@ -4,10 +4,12 @@ import io.mockk.MockKAnnotations
 import io.mockk.every
 import io.mockk.impl.annotations.MockK
 import io.mockk.mockk
+import io.mockk.verify
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.test.TestCoroutineScope
 import mozilla.components.browser.session.Session
 import mozilla.components.browser.session.SessionManager
+import mozilla.components.feature.tab.collections.TabCollection
 import mozilla.components.feature.tabs.TabsUseCases
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertNull
@@ -23,7 +25,7 @@ class DefaultCollectionCreationControllerTest {
 
     private lateinit var controller: DefaultCollectionCreationController
 
-    @MockK private lateinit var store: CollectionCreationStore
+    @MockK(relaxed = true) private lateinit var store: CollectionCreationStore
     @MockK(relaxed = true) private lateinit var dismiss: () -> Unit
     @MockK(relaxed = true) private lateinit var analytics: Analytics
     @MockK private lateinit var tabCollectionStorage: TabCollectionStorage
@@ -92,6 +94,74 @@ class DefaultCollectionCreationControllerTest {
         assertEquals(SaveCollectionStep.SelectCollection, controller.stepBack(SaveCollectionStep.NameCollection))
     }
 
+    @Test
+    fun `GIVEN list of collections WHEN default collection number is required THEN return next default number`() {
+        val collections: MutableList<TabCollection> = ArrayList()
+        collections.add(mockk {
+            every { title } returns "Collection 1"
+        })
+        collections.add(mockk {
+            every { title } returns "Collection 2"
+        })
+        collections.add(mockk {
+            every { title } returns "Collection 3"
+        })
+        every { state.tabCollections } returns collections
+
+        assertEquals(4, controller.getDefaultCollectionNumber())
+
+        collections.add(mockk {
+            every { title } returns "Collection 5"
+        })
+        assertEquals(6, controller.getDefaultCollectionNumber())
+
+        collections.add(mockk {
+            every { title } returns "Random name"
+        })
+        assertEquals(6, controller.getDefaultCollectionNumber())
+
+        collections.add(mockk {
+            every { title } returns "Collection 10 10"
+        })
+        assertEquals(6, controller.getDefaultCollectionNumber())
+    }
+
+    @Test
+    fun `WHEN adding a new collection THEN dispatch NameCollection step changed`() {
+        val collections: List<TabCollection> = ArrayList()
+        every { state.tabCollections } returns collections
+
+        controller.addNewCollection()
+
+        verify { store.dispatch(CollectionCreationAction.StepChanged(SaveCollectionStep.NameCollection, 1)) }
+    }
+
+    @Test
+    fun `GIVEN empty list of collections WHEN saving tabs to collection THEN dispatch NameCollection step changed`() {
+        val collections: List<TabCollection> = ArrayList()
+        every { state.tabCollections } returns collections
+
+        controller.saveTabsToCollection(ArrayList())
+
+        verify { store.dispatch(CollectionCreationAction.StepChanged(SaveCollectionStep.NameCollection, 1)) }
+    }
+
+    @Test
+    fun `GIVEN list of collections WHEN saving tabs to collection THEN dispatch NameCollection step changed`() {
+        val collections: MutableList<TabCollection> = ArrayList()
+        collections.add(mockk {
+            every { title } returns "Collection 1"
+        })
+        collections.add(mockk {
+            every { title } returns "Random Collection"
+        })
+        every { state.tabCollections } returns collections
+
+        controller.saveTabsToCollection(ArrayList())
+
+        verify { store.dispatch(CollectionCreationAction.StepChanged(SaveCollectionStep.SelectCollection, 2)) }
+    }
+
     @Test
     fun `normalSessionSize only counts non-private non-custom sessions`() {
         fun session(isPrivate: Boolean, isCustom: Boolean) = mockk<Session>().apply {