fix(storage): PRAGMA foreign_keys=ON; atomic transaction in complete_subtask_and_check_parent; uncomplete_task moved to storage layer

crates/storage/src/database.rs

@@ -21,6 +21,11 @@ pub async fn init(db_path: &Path) -> Result<SqlitePool> {
         .await
         .map_err(|e| KonError::StorageError(format!("Database connect failed: {e}")))?;
 
+    sqlx::query("PRAGMA foreign_keys = ON")
+        .execute(&pool)
+        .await
+        .map_err(|e| KonError::StorageError(format!("foreign_keys pragma failed: {e}")))?;
+
     run_migrations(&pool).await?;
 
     Ok(pool)
@@ -343,10 +348,14 @@ pub async fn list_subtasks(pool: &SqlitePool, parent_id: &str) -> Result<Vec<Tas
 }
 
 /// Mark a subtask done. If all siblings are now done, auto-complete the parent.
+/// Runs in a transaction so concurrent completions see consistent sibling counts.
 pub async fn complete_subtask_and_check_parent(pool: &SqlitePool, subtask_id: &str) -> Result<()> {
+    let mut tx = pool.begin().await
+        .map_err(|e| KonError::StorageError(format!("Begin transaction failed: {e}")))?;
+
     sqlx::query("UPDATE tasks SET done = 1, done_at = datetime('now') WHERE id = ?")
         .bind(subtask_id)
-        .execute(pool)
+        .execute(&mut *tx)
         .await
         .map_err(|e| KonError::StorageError(format!("Complete subtask failed: {e}")))?;
 
@@ -354,28 +363,31 @@ pub async fn complete_subtask_and_check_parent(pool: &SqlitePool, subtask_id: &s
         "SELECT parent_task_id FROM tasks WHERE id = ?"
     )
     .bind(subtask_id)
-    .fetch_one(pool)
+    .fetch_one(&mut *tx)
     .await
     .map_err(|e| KonError::StorageError(format!("Get parent_task_id failed: {e}")))?;
 
-    let Some(pid) = parent_id else { return Ok(()); };
+    if let Some(pid) = parent_id {
+        let pending: i64 = sqlx::query_scalar(
+            "SELECT COUNT(*) FROM tasks WHERE parent_task_id = ? AND done = 0"
+        )
+        .bind(&pid)
+        .fetch_one(&mut *tx)
+        .await
+        .map_err(|e| KonError::StorageError(format!("Count pending subtasks failed: {e}")))?;
 
-    let pending: i64 = sqlx::query_scalar(
-        "SELECT COUNT(*) FROM tasks WHERE parent_task_id = ? AND done = 0"
-    )
-    .bind(&pid)
-    .fetch_one(pool)
-    .await
-    .map_err(|e| KonError::StorageError(format!("Count pending subtasks failed: {e}")))?;
-
-    if pending == 0 {
-        sqlx::query("UPDATE tasks SET done = 1, done_at = datetime('now') WHERE id = ?")
-            .bind(&pid)
-            .execute(pool)
-            .await
-            .map_err(|e| KonError::StorageError(format!("Auto-complete parent failed: {e}")))?;
+        if pending == 0 {
+            sqlx::query("UPDATE tasks SET done = 1, done_at = datetime('now') WHERE id = ?")
+                .bind(&pid)
+                .execute(&mut *tx)
+                .await
+                .map_err(|e| KonError::StorageError(format!("Auto-complete parent failed: {e}")))?;
+        }
     }
 
+    tx.commit().await
+        .map_err(|e| KonError::StorageError(format!("Commit transaction failed: {e}")))?;
+
     Ok(())
 }
 
@@ -388,6 +400,15 @@ pub async fn complete_task(pool: &SqlitePool, id: &str) -> Result<()> {
     Ok(())
 }
 
+pub async fn uncomplete_task(pool: &SqlitePool, id: &str) -> Result<()> {
+    sqlx::query("UPDATE tasks SET done = 0, done_at = NULL WHERE id = ?")
+        .bind(id)
+        .execute(pool)
+        .await
+        .map_err(|e| KonError::StorageError(format!("Uncomplete task failed: {e}")))?;
+    Ok(())
+}
+
 pub async fn delete_task(pool: &SqlitePool, id: &str) -> Result<()> {
     sqlx::query("DELETE FROM tasks WHERE id = ?")
         .bind(id)

crates/storage/src/lib.rs

@@ -4,7 +4,7 @@ pub mod migrations;
 
 pub use database::{
     add_dictionary_entry, complete_subtask_and_check_parent, complete_task, count_transcripts,
-    delete_dictionary_entry, delete_task, delete_transcript, get_setting, get_task_by_id,
+    delete_dictionary_entry, delete_task, delete_transcript, get_setting, get_task_by_id, uncomplete_task,
     get_transcript, init, insert_subtask, insert_task, insert_transcript, list_dictionary,
     list_recent_errors, list_subtasks, list_tasks, list_transcripts, list_transcripts_paged,
     log_error, search_transcripts, set_setting, update_transcript, DictionaryEntry, ErrorLogRow,

src-tauri/src/commands/tasks.rs

@@ -15,6 +15,7 @@ use kon_storage::{
     insert_task as db_insert_task,
     list_subtasks as db_list_subtasks,
     list_tasks as db_list_tasks,
+    uncomplete_task as db_uncomplete_task,
     TaskRow,
 };
 
@@ -113,12 +114,9 @@ pub async fn uncomplete_task_cmd(
     state: tauri::State<'_, AppState>,
     id: String,
 ) -> Result<(), String> {
-    sqlx::query("UPDATE tasks SET done = 0, done_at = NULL WHERE id = ?")
-        .bind(&id)
-        .execute(&state.db)
+    db_uncomplete_task(&state.db, &id)
         .await
-        .map_err(|e| format!("Uncomplete task failed: {e}"))
-        .map(|_| ())
+        .map_err(|e| e.to_string())
 }
 
 #[tauri::command]