Display nested comment system with LazyColumn Jetpack Compose

CommentListScreen.kt

fun CommentListScreen() {
    val comments by produceDummyComments(10000)
    Box {
        LazyColumn(
            modifier = Modifier
                .systemBarsPadding()
                .fillMaxSize(),
        ) {
            commentList(comments)
        }
        if (comments.isEmpty()) {
            CircularProgressIndicator(modifier = Modifier.align(Alignment.Center))
        }
    }
}

fun LazyListScope.commentList(comments: List<Comment>, level: Int = 0) {
    comments.forEach { comment ->
        commentItem(comment, level)
    }
}

fun LazyListScope.commentItem(comment: Comment, level: Int) {
    item {
        val padding = with(LocalDensity.current) { 16.dp.toPx() }
        Text(
            text = comment.text,
            modifier = Modifier
                .drawBehind {
                    repeat(level + 1) {
                        drawLine(
                            color = Color.Black,
                            start = Offset(it * padding, 0f),
                            end = Offset(it * padding, size.height)
                        )
                    }
                }
                .padding(horizontal = (16.dp * level) + 8.dp, vertical = 4.dp)
        )
    }
    commentList(comment.replies, level + 1)
}

data class Comment(
    val id: String = UUID.randomUUID().toString(),
    val text: String,
    val replies: List<Comment> = emptyList()
)
@Composable
fun produceDummyComments(rootCount: Int): State<List<Comment>> {
    return produceState(initialValue = emptyList()) {
        value = withContext(Dispatchers.Default) { generateComments(rootCount) }
    }
}

fun generateComment(repliesCount: Int, level: Int) = Comment(
    text = LoremIpsum(4)
        .values
        .joinToString(" ")
        .replace('\n', ' '),
    replies = generateComments(repliesCount, level)
)

fun generateComments(commentsCount: Int, level: Int = 0): List<Comment> = buildList {
    if (level < 4) {
        repeat(commentsCount) {
            add(generateComment((0..3).random(), level + 1))
        }
    }
}