Comment tree rework 1 (#162)

* Trying to rework comment tree v1.

* Fixing tree UI triggering.

app/src/main/java/com/jerboa/Utils.kt

@@ -9,6 +9,8 @@ import android.widget.Toast
 import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.material.ScaffoldState
 import androidx.compose.runtime.Stable
+import androidx.compose.runtime.mutableStateListOf
+import androidx.compose.runtime.snapshots.SnapshotStateList
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.drawBehind
 import androidx.compose.ui.graphics.Color
@@ -95,7 +97,8 @@ fun newVote(currentVote: Int?, voteType: VoteType): Int {
 
 data class CommentNodeData(
     val commentView: CommentView,
-    val children: MutableList<CommentNodeData>?,
+    // Must use a SnapshotStateList and not a MutableList here, otherwise changes in the tree children won't trigger a UI update
+    val children: SnapshotStateList<CommentNodeData>?,
     var depth: Int?,
 )
 
@@ -114,7 +117,7 @@ fun buildCommentsTree(
     comments?.forEach { cv ->
         val node = CommentNodeData(
             commentView = cv,
-            children = mutableListOf(),
+            children = mutableStateListOf(),
             depth = null,
         )
         map[cv.comment.id] = node

app/src/main/java/com/jerboa/ui/components/comment/CommentRoutines.kt

@@ -3,8 +3,11 @@ package com.jerboa.ui.components.comment
 import android.content.Context
 import android.util.Log
 import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.mutableStateListOf
+import androidx.compose.runtime.snapshots.SnapshotStateList
 import androidx.compose.ui.focus.FocusManager
 import androidx.navigation.NavController
+import com.jerboa.CommentNodeData
 import com.jerboa.VoteType
 import com.jerboa.api.*
 import com.jerboa.datatypes.CommentView
@@ -24,6 +27,7 @@ import kotlinx.coroutines.launch
 fun likeCommentRoutine(
     commentView: MutableState<CommentView?>,
     comments: MutableList<CommentView>? = null,
+    commentTree: SnapshotStateList<CommentNodeData>? = null,
     voteType: VoteType,
     account: Account,
     ctx: Context,
@@ -39,13 +43,17 @@ fun likeCommentRoutine(
             comments?.also {
                 findAndUpdateComment(comments, updatedCommentView)
             }
+            commentTree?.also {
+                findAndUpdateCommentInTree(commentTree, updatedCommentView)
+            }
         }
     }
 }
 
 fun saveCommentRoutine(
     commentView: MutableState<CommentView?>,
     comments: MutableList<CommentView>? = null,
+    commentTree: SnapshotStateList<CommentNodeData>? = null,
     account: Account,
     ctx: Context,
     scope: CoroutineScope,
@@ -61,6 +69,9 @@ fun saveCommentRoutine(
             comments?.also {
                 findAndUpdateComment(comments, updatedCommentView)
             }
+            commentTree?.also {
+                findAndUpdateCommentInTree(commentTree, updatedCommentView)
+            }
         }
     }
 }
@@ -138,7 +149,7 @@ fun createCommentRoutine(
 
         // Add to all the views which might have your comment
         if (commentView != null) {
-            addCommentToMutableList(postViewModel.comments, commentView)
+            insertCommentIntoTree(postViewModel.commentTree, commentView)
 
             // Maybe a back button would view this page.
             if (account.id == personProfileViewModel.personId.value) {
@@ -185,7 +196,7 @@ fun editCommentRoutine(
 
             // Update all the views which might have your comment
             findAndUpdateComment(personProfileViewModel.comments, commentView.value)
-            findAndUpdateComment(postViewModel.comments, commentView.value)
+            findAndUpdateCommentInTree(postViewModel.commentTree, commentView.value)
             findAndUpdateComment(inboxViewModel.replies, commentView.value)
 
             navController.navigateUp()
@@ -196,6 +207,7 @@ fun editCommentRoutine(
 fun deleteCommentRoutine(
     commentView: MutableState<CommentView?>,
     comments: MutableList<CommentView>? = null,
+    commentTree: SnapshotStateList<CommentNodeData>? = null,
     account: Account,
     ctx: Context,
     scope: CoroutineScope,
@@ -212,6 +224,9 @@ fun deleteCommentRoutine(
             comments?.also {
                 findAndUpdateComment(comments, deletedCommentView)
             }
+            commentTree?.also {
+                findAndUpdateCommentInTree(commentTree, deletedCommentView)
+            }
         }
     }
 }
@@ -249,6 +264,63 @@ fun findAndUpdateComment(
     }
 }
 
+fun insertCommentIntoTree(
+    commentTree: MutableList<CommentNodeData>,
+    cv: CommentView
+) {
+    var nodeData = CommentNodeData(
+        commentView = cv,
+        children = null,
+        depth = null,
+    )
+    cv.comment.parent_id?.also { parentId ->
+        val foundIndex = commentTree.indexOfFirst {
+            it.commentView.comment.id == parentId
+        }
+
+        if (foundIndex != -1) {
+            val parent = commentTree[foundIndex]
+            nodeData.depth = parent.depth?.plus(1) ?: 0
+
+            parent.children?.also { children ->
+                children.add(0, nodeData)
+            } ?: run {
+                commentTree[foundIndex] = parent.copy(children = mutableStateListOf(nodeData))
+            }
+        } else {
+            commentTree.forEach { node ->
+                node.children?.also { children ->
+                    insertCommentIntoTree(children, cv)
+                }
+            }
+        }
+    } ?: run {
+        commentTree.add(0, nodeData)
+    }
+}
+
+fun findAndUpdateCommentInTree(
+    commentTree: SnapshotStateList<CommentNodeData>,
+    cv: CommentView?
+) {
+    cv?.also {
+        val foundIndex = commentTree.indexOfFirst {
+            it.commentView.comment.id == cv.comment.id
+        }
+
+        if (foundIndex != -1) {
+            val updatedComment = commentTree[foundIndex].copy(commentView = cv)
+            commentTree[foundIndex] = updatedComment
+        } else {
+            commentTree.forEach { node ->
+                node.children?.also { children ->
+                    findAndUpdateCommentInTree(children, cv)
+                }
+            }
+        }
+    }
+}
+
 fun addCommentToMutableList(
     comments: MutableList<CommentView>,
     newCommentView: CommentView

app/src/main/java/com/jerboa/ui/components/post/PostActivity.kt

@@ -10,15 +10,14 @@ import androidx.compose.material.LinearProgressIndicator
 import androidx.compose.material.MaterialTheme
 import androidx.compose.material.Scaffold
 import androidx.compose.material.Surface
+import androidx.compose.runtime.*
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.navigation.NavController
 import com.google.accompanist.swiperefresh.SwipeRefresh
 import com.google.accompanist.swiperefresh.rememberSwipeRefreshState
 import com.jerboa.VoteType
-import com.jerboa.buildCommentsTree
-import com.jerboa.datatypes.SortType
 import com.jerboa.db.AccountViewModel
 import com.jerboa.isModerator
 import com.jerboa.openLink
@@ -57,7 +56,6 @@ fun PostActivity(
     val ctx = LocalContext.current
 
     val account = getCurrentAccount(accountViewModel = accountViewModel)
-    val commentNodes = buildCommentsTree(postViewModel.comments, SortType.Hot)
 
     val swipeRefreshState = rememberSwipeRefreshState(
         isRefreshing = postViewModel.loading && postViewModel
@@ -200,7 +198,7 @@ fun PostActivity(
                                 )
                             }
                             // Can't really do scrolling well here either because of tree
-                            items(commentNodes) { node ->
+                            items(postViewModel.commentTree) { node ->
                                 CommentNode(
                                     node = node,
                                     onUpvoteClick = { commentView ->

app/src/main/java/com/jerboa/ui/components/post/PostViewModel.kt

@@ -8,13 +8,16 @@ import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.setValue
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
+import com.jerboa.CommentNodeData
 import com.jerboa.VoteType
 import com.jerboa.api.API
 import com.jerboa.api.retrofitErrorHandler
+import com.jerboa.buildCommentsTree
 import com.jerboa.datatypes.CommentView
 import com.jerboa.datatypes.CommunityModeratorView
 import com.jerboa.datatypes.PersonSafe
 import com.jerboa.datatypes.PostView
+import com.jerboa.datatypes.SortType
 import com.jerboa.datatypes.api.GetPost
 import com.jerboa.datatypes.api.GetPostResponse
 import com.jerboa.db.Account
@@ -33,7 +36,7 @@ class PostViewModel : ViewModel() {
         private set
     var postView = mutableStateOf<PostView?>(null)
         private set
-    var comments = mutableStateListOf<CommentView>()
+    var commentTree = mutableStateListOf<CommentNodeData>()
         private set
     var moderators = mutableStateListOf<CommunityModeratorView>()
         private set
@@ -64,8 +67,8 @@ class PostViewModel : ViewModel() {
                 val out = retrofitErrorHandler(api.getPost(form = form.serializeToMap()))
                 res = out
                 postView.value = out.post_view
-                comments.clear()
-                comments.addAll(out.comments)
+                commentTree.clear()
+                commentTree.addAll(buildCommentsTree(out.comments, SortType.Hot))
                 moderators.clear()
                 moderators.addAll(out.moderators)
             } catch (e: Exception) {
@@ -85,7 +88,7 @@ class PostViewModel : ViewModel() {
         likeCommentRoutine(
             commentView = mutableStateOf(commentView),
             voteType = voteType,
-            comments = comments,
+            commentTree = commentTree,
             account = account,
             ctx = ctx,
             scope = viewModelScope,
@@ -95,7 +98,7 @@ class PostViewModel : ViewModel() {
     fun deleteComment(commentView: CommentView, account: Account, ctx: Context) {
         deleteCommentRoutine(
             commentView = mutableStateOf(commentView),
-            comments = comments, // TODO should this be here?
+            commentTree = commentTree,
             account = account,
             ctx = ctx,
             scope = viewModelScope,
@@ -125,7 +128,7 @@ class PostViewModel : ViewModel() {
     ) {
         saveCommentRoutine(
             commentView = mutableStateOf(commentView),
-            comments = comments,
+            commentTree = commentTree,
             account = account,
             ctx = ctx,
             scope = viewModelScope,