feat(storage): add parent_task_id migration for micro-stepping

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/storage/src/database.rs

@@ -194,7 +194,7 @@ pub async fn insert_task(
 
 pub async fn list_tasks(pool: &SqlitePool) -> Result<Vec<TaskRow>> {
     let rows =
-        sqlx::query("SELECT id, text, bucket, list_id, effort, done, done_at, created_at, source_transcript_id, priority, project, status, updated_at, sort_order, notes FROM tasks ORDER BY sort_order ASC, created_at DESC")
+        sqlx::query("SELECT id, text, bucket, list_id, effort, done, done_at, created_at, source_transcript_id, priority, project, status, updated_at, sort_order, notes, parent_task_id FROM tasks ORDER BY sort_order ASC, created_at DESC")
             .fetch_all(pool)
             .await
             .map_err(|e| KonError::StorageError(format!("List tasks failed: {e}")))?;
@@ -303,7 +303,7 @@ pub async fn list_tasks_by_status(
     limit: i64,
 ) -> Result<Vec<TaskRow>> {
     let rows = sqlx::query(
-        "SELECT id, text, bucket, list_id, effort, done, done_at, created_at, source_transcript_id, priority, project, status, updated_at, sort_order, notes
+        "SELECT id, text, bucket, list_id, effort, done, done_at, created_at, source_transcript_id, priority, project, status, updated_at, sort_order, notes, parent_task_id
          FROM tasks WHERE status = ?
          ORDER BY sort_order ASC, created_at DESC
          LIMIT ?",
@@ -317,6 +317,49 @@ pub async fn list_tasks_by_status(
     Ok(rows.into_iter().map(task_row_from).collect())
 }
 
+// --- Subtask (micro-step) queries ---
+
+/// List subtasks (children) of a parent task, ordered by sort_order.
+pub async fn list_subtasks(pool: &SqlitePool, parent_task_id: &str) -> Result<Vec<TaskRow>> {
+    let rows = sqlx::query(
+        "SELECT id, text, bucket, list_id, effort, done, done_at, created_at, source_transcript_id, priority, project, status, updated_at, sort_order, notes, parent_task_id
+         FROM tasks WHERE parent_task_id = ?
+         ORDER BY sort_order ASC",
+    )
+    .bind(parent_task_id)
+    .fetch_all(pool)
+    .await
+    .map_err(|e| KonError::StorageError(format!("List subtasks failed: {e}")))?;
+
+    Ok(rows.into_iter().map(task_row_from).collect())
+}
+
+/// Check whether all subtasks of a parent are done.
+pub async fn all_subtasks_done(pool: &SqlitePool, parent_task_id: &str) -> Result<bool> {
+    let count: i64 = sqlx::query_scalar(
+        "SELECT COUNT(*) FROM tasks WHERE parent_task_id = ? AND done = 0",
+    )
+    .bind(parent_task_id)
+    .fetch_one(pool)
+    .await
+    .map_err(|e| KonError::StorageError(format!("Check subtasks failed: {e}")))?;
+
+    Ok(count == 0)
+}
+
+/// Check whether a task has any subtasks.
+pub async fn has_subtasks(pool: &SqlitePool, task_id: &str) -> Result<bool> {
+    let count: i64 = sqlx::query_scalar(
+        "SELECT COUNT(*) FROM tasks WHERE parent_task_id = ?",
+    )
+    .bind(task_id)
+    .fetch_one(pool)
+    .await
+    .map_err(|e| KonError::StorageError(format!("Check has subtasks failed: {e}")))?;
+
+    Ok(count > 0)
+}
+
 // --- FTS5 Search ---
 
 /// Full-text search across transcripts using the FTS5 virtual table.
@@ -455,6 +498,8 @@ pub struct TaskRow {
     pub updated_at: String,
     pub sort_order: i64,
     pub notes: String,
+    // v3 field
+    pub parent_task_id: Option<String>,
 }
 
 #[derive(Debug, Clone)]
@@ -484,6 +529,7 @@ fn task_row_from(r: sqlx::sqlite::SqliteRow) -> TaskRow {
         updated_at: r.get("updated_at"),
         sort_order: r.get("sort_order"),
         notes: r.get("notes"),
+        parent_task_id: r.get("parent_task_id"),
     }
 }
 

crates/storage/src/lib.rs

@@ -3,10 +3,11 @@ pub mod file_storage;
 pub mod migrations;
 
 pub use database::{
-    clear_timer_state, complete_task, delete_task, delete_transcript, get_segments,
-    get_setting, get_timer_state, get_transcript, init, insert_segments, insert_task,
-    insert_task_v2, insert_transcript, list_tasks, list_tasks_by_status, list_transcripts,
-    log_error, reorder_tasks, save_timer_state, search_transcripts, set_setting,
-    update_task_v2, InsertTranscriptParams, SegmentRow, TaskRow, TimerStateRow, TranscriptRow,
+    all_subtasks_done, clear_timer_state, complete_task, delete_task, delete_transcript,
+    get_segments, get_setting, get_timer_state, get_transcript, has_subtasks, init,
+    insert_segments, insert_task, insert_task_v2, insert_transcript, list_subtasks, list_tasks,
+    list_tasks_by_status, list_transcripts, log_error, reorder_tasks, save_timer_state,
+    search_transcripts, set_setting, update_task_v2, InsertTranscriptParams, SegmentRow,
+    TaskRow, TimerStateRow, TranscriptRow,
 };
 pub use file_storage::{app_data_dir, database_path, recordings_dir};

crates/storage/src/migrations.rs

@@ -118,6 +118,10 @@ const MIGRATIONS: &[(i64, &str, &str)] = &[
         CREATE INDEX IF NOT EXISTS idx_tasks_priority ON tasks(priority);
         CREATE INDEX IF NOT EXISTS idx_tasks_project ON tasks(project)
     "#),
+    (3, "phase 2b — parent_task_id for micro-stepping", r#"
+        ALTER TABLE tasks ADD COLUMN parent_task_id TEXT;
+        CREATE INDEX IF NOT EXISTS idx_tasks_parent ON tasks(parent_task_id)
+    "#),
 ];
 
 /// Split SQL text into individual statements, respecting BEGIN...END blocks
@@ -236,7 +240,7 @@ mod tests {
             .fetch_one(&pool)
             .await
             .unwrap();
-        assert_eq!(count, 2);
+        assert_eq!(count, 3);
 
         sqlx::query("INSERT INTO settings (key, value) VALUES ('test', 'value')")
             .execute(&pool)
@@ -279,6 +283,6 @@ mod tests {
             .fetch_one(&pool)
             .await
             .unwrap();
-        assert_eq!(count, 2);
+        assert_eq!(count, 3);
     }
 }