feat: client cascade delete with dependency counts

src-tauri/src/commands.rs

@@ -110,11 +110,66 @@ pub fn update_client(state: State<AppState>, client: Client) -> Result<(), Strin
     Ok(())
 }
 
+#[tauri::command]
+pub fn get_client_dependents(state: State<AppState>, client_id: i64) -> Result<serde_json::Value, String> {
+    let conn = state.db.lock().map_err(|e| e.to_string())?;
+    let project_count: i64 = conn.query_row(
+        "SELECT COUNT(*) FROM projects WHERE client_id = ?1", params![client_id], |row| row.get(0)
+    ).map_err(|e| e.to_string())?;
+    let invoice_count: i64 = conn.query_row(
+        "SELECT COUNT(*) FROM invoices WHERE client_id = ?1", params![client_id], |row| row.get(0)
+    ).map_err(|e| e.to_string())?;
+    let expense_count: i64 = conn.query_row(
+        "SELECT COUNT(*) FROM expenses WHERE client_id = ?1", params![client_id], |row| row.get(0)
+    ).map_err(|e| e.to_string())?;
+    Ok(serde_json::json!({
+        "projects": project_count,
+        "invoices": invoice_count,
+        "expenses": expense_count
+    }))
+}
+
 #[tauri::command]
 pub fn delete_client(state: State<AppState>, id: i64) -> Result<(), String> {
     let conn = state.db.lock().map_err(|e| e.to_string())?;
-    conn.execute("DELETE FROM clients WHERE id = ?1", params![id]).map_err(|e| e.to_string())?;
-    Ok(())
+
+    conn.execute_batch("BEGIN TRANSACTION").map_err(|e| e.to_string())?;
+
+    let result = (|| -> Result<(), rusqlite::Error> {
+        let project_ids: Vec<i64> = {
+            let mut stmt = conn.prepare("SELECT id FROM projects WHERE client_id = ?1")?;
+            let rows = stmt.query_map(params![id], |row| row.get(0))?;
+            rows.filter_map(|r| r.ok()).collect()
+        };
+
+        for pid in &project_ids {
+            conn.execute("DELETE FROM entry_tags WHERE entry_id IN (SELECT id FROM time_entries WHERE project_id = ?1)", params![pid])?;
+            conn.execute("DELETE FROM time_entries WHERE project_id = ?1", params![pid])?;
+            conn.execute("DELETE FROM tasks WHERE project_id = ?1", params![pid])?;
+            conn.execute("DELETE FROM tracked_apps WHERE project_id = ?1", params![pid])?;
+            conn.execute("DELETE FROM favorites WHERE project_id = ?1", params![pid])?;
+            conn.execute("DELETE FROM recurring_entries WHERE project_id = ?1", params![pid])?;
+            conn.execute("DELETE FROM timeline_events WHERE project_id = ?1", params![pid])?;
+        }
+
+        conn.execute("DELETE FROM expenses WHERE client_id = ?1", params![id])?;
+        conn.execute("DELETE FROM invoice_items WHERE invoice_id IN (SELECT id FROM invoices WHERE client_id = ?1)", params![id])?;
+        conn.execute("DELETE FROM invoices WHERE client_id = ?1", params![id])?;
+        conn.execute("DELETE FROM projects WHERE client_id = ?1", params![id])?;
+        conn.execute("DELETE FROM clients WHERE id = ?1", params![id])?;
+        Ok(())
+    })();
+
+    match result {
+        Ok(()) => {
+            conn.execute_batch("COMMIT").map_err(|e| e.to_string())?;
+            Ok(())
+        }
+        Err(e) => {
+            conn.execute_batch("ROLLBACK").ok();
+            Err(e.to_string())
+        }
+    }
 }
 
 // Project commands

src-tauri/src/lib.rs

@@ -45,6 +45,7 @@ pub fn run() {
             commands::create_client,
             commands::update_client,
             commands::delete_client,
+            commands::get_client_dependents,
             commands::get_projects,
             commands::create_project,
             commands::update_project,