Fixing line jump to top (#585)

leandroBorgesFerreira · web-flow · commit 05803d3594a2 · 2026-04-12T14:53:17.000-03:00
* Fixing line jump to top

* code clean
diff --git a/writeopia/src/commonMain/kotlin/io/writeopia/sdk/model/story/Selection.kt b/writeopia/src/commonMain/kotlin/io/writeopia/sdk/model/story/Selection.kt
@@ -7,7 +7,12 @@ package io.writeopia.sdk.model.story
  * @property end the end of the cursor in the paragraph
  * @property position the position of the paragraph (which line the cursor is)
  */
-data class Selection(val start: Int, val end: Int, val position: Int) {
+data class Selection(
+    val start: Int,
+    val end: Int,
+    val position: Int,
+    val fromEnd: Boolean = false
+) {
     fun key() = if (start == end) hashCode() else 0
 
     fun sortedPositions(): Pair<Int, Int> = if (start < end) start to end else end to start
@@ -19,5 +24,8 @@ data class Selection(val start: Int, val end: Int, val position: Int) {
 
         fun fromPosition(cursorPosition: Int, stepPosition: Int) =
             Selection(cursorPosition, cursorPosition, stepPosition)
+
+        fun fromLastLine(cursorPosition: Int, stepPosition: Int) =
+            Selection(cursorPosition, cursorPosition, stepPosition, fromEnd = true)
     }
 }
diff --git a/writeopia_ui/src/commonMain/kotlin/io/writeopia/ui/drawer/content/TextDrawer.kt b/writeopia_ui/src/commonMain/kotlin/io/writeopia/ui/drawer/content/TextDrawer.kt
@@ -119,6 +119,18 @@ class TextDrawer(
         var textLayoutResult by remember {
             mutableStateOf<TextLayoutResult?>(null)
         }
+
+        // Recalculate selection for last-line positioning when layout becomes available
+        LaunchedEffect(textLayoutResult, drawInfo.selection) {
+            val selection = drawInfo.selection
+            if (selection != null && selection.fromEnd && textLayoutResult != null) {
+                val newRange = selection.toTextRange(step.text ?: "", textLayoutResult)
+                if (inputText.selection != newRange) {
+                    inputText = inputText.copy(selection = newRange)
+                }
+            }
+        }
+
         val cursorLine by remember {
             derivedStateOf {
                 textLayoutResult?.getLineForOffset(inputText.selection.end)
diff --git a/writeopia_ui/src/commonMain/kotlin/io/writeopia/ui/extensions/SelectionExtensions.kt b/writeopia_ui/src/commonMain/kotlin/io/writeopia/ui/extensions/SelectionExtensions.kt
@@ -1,8 +1,26 @@
 package io.writeopia.ui.extensions
 
+import androidx.compose.ui.text.TextLayoutResult
 import androidx.compose.ui.text.TextRange
 import io.writeopia.sdk.model.story.Selection
 import kotlin.math.min
 
 fun Selection.toTextRange(text: String) =
     TextRange(start = min(start, text.length), end = min(end, text.length))
+
+fun Selection.toTextRange(text: String, textLayoutResult: TextLayoutResult?): TextRange =
+    when {
+        fromEnd && textLayoutResult != null && textLayoutResult.lineCount > 0 -> {
+            val lastLineIndex = textLayoutResult.lineCount - 1
+            val lastLineStart = textLayoutResult.getLineStart(lastLineIndex)
+            val lastLineEnd = textLayoutResult.getLineEnd(lastLineIndex)
+            val lastLineLength = lastLineEnd - lastLineStart
+            val cursorPos = lastLineStart + min(start, lastLineLength)
+            TextRange(cursorPos, cursorPos)
+        }
+
+        // Fallback when no layout yet: position at end, will be corrected later
+        fromEnd -> TextRange(text.length, text.length)
+
+        else -> TextRange(start = min(start, text.length), end = min(end, text.length))
+    }
diff --git a/writeopia_ui/src/commonMain/kotlin/io/writeopia/ui/manager/WriteopiaStateManager.kt b/writeopia_ui/src/commonMain/kotlin/io/writeopia/ui/manager/WriteopiaStateManager.kt
@@ -1282,7 +1282,7 @@ class WriteopiaStateManager(
 
                     _currentStory.value = storyState.copy(
                         focus = newPosition,
-                        selection = Selection.fromPosition(cursor, newPosition),
+                        selection = Selection.fromLastLine(cursor, newPosition),
                         stories = mutable
                     )
                 }

Original file line number	Diff line number	Diff line change
`@@ -1282,7 +1282,7 @@ class WriteopiaStateManager(`
`1282`	`1282`
`1283`	`1283`	`_currentStory.value = storyState.copy(`
`1284`	`1284`	`focus = newPosition,`
`1285`		`- selection = Selection.fromPosition(cursor, newPosition),`
	`1285`	`+ selection = Selection.fromLastLine(cursor, newPosition),`
`1286`	`1286`	`stories = mutable`
`1287`	`1287`	`)`
`1288`	`1288`	`}`