chore: comments and code enhancements on DisplayFolders to TreeFolder conversion

Author: ClemRiviere

feature/navigation/drawer/dropdown/src/debug/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/ui/folder/FolderListPreview.kt

@@ -43,12 +43,10 @@ internal fun FolderListPreviewSelected() {
 internal fun FolderListWithUnifiedFolderPreview() {
     PreviewWithTheme {
         FolderList(
-            rootFolder = TreeFolder.createFromFolders(
-                persistentListOf(
-                    UNIFIED_FOLDER,
-                    DISPLAY_FOLDER,
-                ),
-            ),
+            rootFolder = TreeFolder.createFromFolders(persistentListOf(
+                UNIFIED_FOLDER,
+                DISPLAY_FOLDER,
+            )),
             selectedFolder = DISPLAY_FOLDER,
             onFolderClick = {},
             showStarredCount = false,

feature/navigation/drawer/dropdown/src/main/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/domain/entity/TreeFolder.kt

@@ -3,67 +3,76 @@ package net.thunderbird.feature.navigation.drawer.dropdown.domain.entity
 import app.k9mail.core.mail.folder.api.Folder
 import app.k9mail.core.mail.folder.api.FolderType
 
-internal data class TreeFolder(
-    var value: DisplayFolder? = null,
+internal class TreeFolder(
+    var displayFolder: DisplayFolder? = null,
 ) {
     companion object {
         fun createFromFolders(folders: List<DisplayFolder>, maxDepth: Int = 3): TreeFolder {
-            // Converting folders to TreeFolder
+            // Preparing root
             val rootFolder = TreeFolder()
-            var currentTree = rootFolder
 
             for (displayFolder in folders) {
+                // Managing exceptions
                 if (displayFolder is DisplayUnifiedFolder) {
-                    currentTree.children.add(TreeFolder(displayFolder))
+                    rootFolder.children.add(TreeFolder(displayFolder))
                 }
                 if (displayFolder !is DisplayAccountFolder) continue
-                val splittedFolderName = displayFolder.folder.name.split("/", limit = maxDepth + 1)
-                var subFolderEntireName = ""
-                for (subFolderName in splittedFolderName) {
-                    subFolderEntireName += subFolderName
-                    var foundInChildren = false
-                    for (children in currentTree.children) {
-                        var childDisplayFolder = children.value
-                        if (childDisplayFolder !is DisplayAccountFolder) continue
-                        if (childDisplayFolder.folder.name == subFolderEntireName) {
-                            currentTree = children
-                            foundInChildren = true
-                            break
-                        }
+
+                // Inserting folder in tree
+                insertFolderInCurrentTree(rootFolder, displayFolder, maxDepth)
+            }
+
+            return rootFolder
+        }
+
+        private fun insertFolderInCurrentTree(
+            rootTree: TreeFolder,
+            displayFolder: DisplayAccountFolder,
+            maxDepth: Int,
+        ) {
+            val splittedFolderName = displayFolder.folder.name.split("/", limit = maxDepth + 1)
+            var currentWorkingPath = ""
+            var currentTree = rootTree
+
+            for (subFolderName in splittedFolderName) {
+                currentWorkingPath += subFolderName
+
+                // finding subFolderEntireName (current working path) into currentTree children
+                val foundChild = currentTree.children.find { child ->
+                    val childDisplayFolder = child.displayFolder
+                    childDisplayFolder is DisplayAccountFolder && childDisplayFolder.folder.name == currentWorkingPath
+                }
+
+                if (foundChild != null) {
+                    // if found, association the value to manage fake created subFolders
+                    currentTree = foundChild
+                    if (currentWorkingPath == displayFolder.folder.name) {
+                        currentTree.displayFolder = displayFolder
                     }
-                    if (!foundInChildren) {
-                        var newChildren = TreeFolder()
-                        if (subFolderEntireName == displayFolder.folder.name) {
-                            newChildren = TreeFolder(displayFolder)
-                        } else {
-                            newChildren = TreeFolder(
-                                DisplayAccountFolder(
-                                    displayFolder.accountId,
-                                    Folder(
-                                        0,
-                                        subFolderEntireName,
-                                        FolderType.REGULAR,
-                                        displayFolder.folder.isLocalOnly,
-                                    ),
-                                    displayFolder.isInTopGroup,
-                                    0,
-                                    0,
-                                ),
-                            )
-                        }
-                        currentTree.children.add(newChildren)
-                        currentTree = newChildren
+                } else {
+                    // if not found in children, creating a new one
+                    var newChildren = TreeFolder()
+                    if (currentWorkingPath == displayFolder.folder.name) {
+                        // if it is the final subfolder, adding displayFolder in it
+                        newChildren = TreeFolder(displayFolder)
                     } else {
-                        if (subFolderEntireName == displayFolder.folder.name) {
-                            currentTree.value = displayFolder
-                        }
+                        // if just an intermediate, adding a fake subFolder
+                        newChildren = TreeFolder(
+                            DisplayAccountFolder(
+                                displayFolder.accountId,
+                                Folder(0, currentWorkingPath, FolderType.REGULAR, displayFolder.folder.isLocalOnly),
+                                displayFolder.isInTopGroup,
+                                0,
+                                0,
+                            ),
+                        )
                     }
-                    subFolderEntireName += "/"
+                    currentTree.children.add(newChildren)
+                    currentTree = newChildren
                 }
-                currentTree = rootFolder
-            }
 
-            return rootFolder
+                currentWorkingPath += "/"
+            }
         }
     }
 
@@ -74,14 +83,14 @@ internal data class TreeFolder(
         for (child in children) {
             allUnreadMessageCount += child.getAllUnreadMessageCount()
         }
-        return allUnreadMessageCount + (value?.unreadMessageCount ?: 0)
+        return allUnreadMessageCount + (displayFolder?.unreadMessageCount ?: 0)
     }
 
     fun getAllStarredMessageCount(): Int {
         var allStarredMessageCount = 0
         for (child in children) {
             allStarredMessageCount += child.getAllStarredMessageCount()
         }
-        return allStarredMessageCount + (value?.starredMessageCount ?: 0)
+        return allStarredMessageCount + (displayFolder?.starredMessageCount ?: 0)
     }
 }

feature/navigation/drawer/dropdown/src/main/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/domain/usecase/GetTreeFolders.kt

@@ -4,7 +4,7 @@ import net.thunderbird.feature.navigation.drawer.dropdown.domain.DomainContract.
 import net.thunderbird.feature.navigation.drawer.dropdown.domain.entity.DisplayFolder
 import net.thunderbird.feature.navigation.drawer.dropdown.domain.entity.TreeFolder
 
-internal class GetTreeFolders() : UseCase.GetTreeFolders {
+internal class GetTreeFolders : UseCase.GetTreeFolders {
     override fun invoke(folders: List<DisplayFolder>, maxDepth: Int): TreeFolder {
         return TreeFolder.createFromFolders(folders, maxDepth)
     }

feature/navigation/drawer/dropdown/src/main/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/ui/folder/FolderList.kt

@@ -38,9 +38,9 @@ internal fun FolderList(
     ) {
         items(
             items = rootFolder.children,
-            key = { it.value?.id ?: '0' },
+            key = { it.displayFolder?.id ?: '0' },
         ) { folder ->
-            val currentDisplayFolder = folder.value
+            val currentDisplayFolder = folder.displayFolder
             if (currentDisplayFolder is DisplayAccountFolder) {
                 FolderListItem(
                     displayFolder = currentDisplayFolder,

feature/navigation/drawer/dropdown/src/main/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/ui/folder/FolderListItem.kt

@@ -33,6 +33,7 @@ internal fun FolderListItem(
     modifier: Modifier = Modifier,
     treeFolder: TreeFolder? = null,
     parentPrefix: String? = "",
+    indentationLevel: Int = 1,
 ) {
     var isExpanded = remember { mutableStateOf(false) }
 
@@ -44,43 +45,44 @@ internal fun FolderListItem(
         starredCount = treeFolder.getAllStarredMessageCount()
     }
 
-    NavigationDrawerItem(
-        label = mapFolderName(displayFolder, folderNameFormatter, parentPrefix),
-        selected = selected,
-        onClick = { onClick(displayFolder) },
-        modifier = modifier,
-        icon = {
-            Icon(
-                imageVector = mapFolderIcon(displayFolder),
-            )
-        },
-        badge = {
-            FolderListItemBadge(
-                unreadCount = unreadCount,
-                starredCount = starredCount,
-                showStarredCount = showStarredCount,
-                expandableState = if (treeFolder !== null && treeFolder.children.isNotEmpty()) isExpanded else null,
-            )
-        },
-    )
-
-    // Managing children
     Column(modifier = Modifier.fillMaxWidth().animateContentSize()) {
+        NavigationDrawerItem(
+            label = mapFolderName(displayFolder, folderNameFormatter, parentPrefix),
+            selected = selected,
+            onClick = { onClick(displayFolder) },
+            modifier = modifier,
+            icon = {
+                Icon(
+                    imageVector = mapFolderIcon(displayFolder),
+                )
+            },
+            badge = {
+                FolderListItemBadge(
+                    unreadCount = unreadCount,
+                    starredCount = starredCount,
+                    showStarredCount = showStarredCount,
+                    expandableState = if (treeFolder !== null && treeFolder.children.isNotEmpty()) isExpanded else null,
+                )
+            },
+        )
+
+        // Managing children
         if (!isExpanded.value) return
         if (treeFolder === null) return
         for (child in treeFolder.children) {
-            var displayParent = treeFolder.value
-            var displayChild = child.value
+            var displayParent = treeFolder.displayFolder
+            var displayChild = child.displayFolder
             if (displayChild === null) continue
             FolderListItem(
                 displayFolder = displayChild,
                 selected = false,
                 showStarredCount = showStarredCount,
                 onClick = { onClick(displayChild) },
                 folderNameFormatter = folderNameFormatter,
-                modifier = modifier.then(Modifier.padding(start = MainTheme.spacings.triple)),
+                modifier = Modifier.padding(start = MainTheme.spacings.triple * indentationLevel),
                 treeFolder = child,
                 parentPrefix = if (displayParent is DisplayAccountFolder) displayParent.folder.name else null,
+                indentationLevel = indentationLevel + 1,
             )
         }
     }