# GUI Feature Enhancement Plan

**Overall Goal:** Modify the GUI (`gui/main_window.py`, `gui/prediction_handler.py`) to make the output path configurable, improve UI responsiveness during preview generation, and add a toggle to switch between detailed file preview and a simple input path list.

**Detailed Plan:**

1.  **Feature: Configurable Output Path**
    *   **File:** `gui/main_window.py`
    *   **Changes:**
        *   **UI Addition:**
            *   Below the `preset_combo` layout, add a new `QHBoxLayout`.
            *   Inside this layout, add:
                *   A `QLabel` with text "Output Directory:".
                *   A `QLineEdit` (e.g., `self.output_path_edit`) to display/edit the path. Make it read-only initially if preferred, or editable.
                *   A `QPushButton` (e.g., `self.browse_output_button`) with text "Browse...".
        *   **Initialization (`__init__` or `setup_main_panel_ui`):**
            *   Read the default `OUTPUT_BASE_DIR` from `core_config`.
            *   Resolve this path relative to the project root (`project_root / output_base_dir_config`).
            *   Set the initial text of `self.output_path_edit` to this resolved default path.
        *   **Browse Button Logic:**
            *   Connect the `clicked` signal of `self.browse_output_button` to a new method (e.g., `_browse_for_output_directory`).
            *   Implement `_browse_for_output_directory`:
                *   Use `QFileDialog.getExistingDirectory` to let the user select a folder.
                *   If a directory is selected, update the text of `self.output_path_edit`.
        *   **Processing Logic (`start_processing`):**
            *   Instead of reading/resolving the path from `core_config`, get the path string directly from `self.output_path_edit.text()`.
            *   Convert this string to a `Path` object.
            *   **Add Validation:** Before passing the path to the handler, check if the directory exists. If not, attempt to create it using `output_dir.mkdir(parents=True, exist_ok=True)`. Handle potential `OSError` exceptions during creation and show an error message if it fails. Also, consider adding a basic writability check if possible.
            *   Pass the validated `output_dir_str` to `self.processing_handler.run_processing`.

2.  **Feature: Responsive UI (Address Prediction Bottleneck)**
    *   **File:** `gui/prediction_handler.py`
    *   **Changes:**
        *   **Import:** Add `from concurrent.futures import ThreadPoolExecutor, as_completed`.
        *   **Modify `run_prediction`:**
            *   Inside the `try` block (after loading `config`), create a `ThreadPoolExecutor` (e.g., `with ThreadPoolExecutor(max_workers=...) as executor:`). Determine a reasonable `max_workers` count (e.g., `os.cpu_count() // 2` or a fixed number like 4 or 8).
            *   Instead of iterating through `input_paths` sequentially, submit a task to the executor for each `input_path_str`.
            *   The task submitted should be a helper method (e.g., `_predict_single_asset`) that takes `input_path_str` and the loaded `config` object as arguments.
            *   `_predict_single_asset` will contain the logic currently inside the loop: instantiate `AssetProcessor`, call `get_detailed_file_predictions`, handle exceptions, and return the list of prediction dictionaries for that *single* asset (or an error dictionary).
            *   Store the `Future` objects returned by `executor.submit`.
            *   Use `as_completed(futures)` to process results as they become available.
            *   Append the results from each completed future to the `all_file_results` list.
            *   Emit `prediction_results_ready` once at the very end with the complete `all_file_results` list.
    *   **File:** `gui/main_window.py`
    *   **Changes:**
        *   No changes needed in the `on_prediction_results_ready` slot itself, as the handler will still emit the full list at the end.

3.  **Feature: Preview Toggle**
    *   **File:** `gui/main_window.py`
    *   **Changes:**
        *   **UI Addition:**
            *   Add a `QCheckBox` (e.g., `self.disable_preview_checkbox`) with text "Disable Detailed Preview". Place it logically, perhaps near the `overwrite_checkbox` or above the `preview_table`. Set its default state to unchecked.
        *   **Modify `update_preview`:**
            *   At the beginning of the method, check `self.disable_preview_checkbox.isChecked()`.
            *   **If Checked (Simple View):**
                *   Clear the `preview_table`.
                *   Set simplified table headers (e.g., `self.preview_table.setColumnCount(1); self.preview_table.setHorizontalHeaderLabels(["Input Path"])`). Adjust column resize modes.
                *   Iterate through `self.current_asset_paths`. For each path, add a row to the table containing just the path string.
                *   Set status bar message (e.g., "Preview disabled. Showing input list.").
                *   **Crucially:** `return` from the method here to prevent the `PredictionHandler` from being started.
            *   **If Unchecked (Detailed View):**
                *   Ensure the table headers and column count are set back to the detailed view configuration (Status, Original Path, Predicted Name, Details).
                *   Continue with the rest of the existing `update_preview` logic to start the `PredictionHandler`.
        *   **Connect Signal:** In `__init__` or `setup_main_panel_ui`, connect the `toggled` signal of `self.disable_preview_checkbox` to the `self.update_preview` slot.
        *   **Initial State:** Ensure the first call to `update_preview` (if any) respects the initial unchecked state of the checkbox.

**Mermaid Diagram:**

```mermaid
graph TD
    subgraph MainWindow
        A[User Action: Add Asset / Change Preset / Toggle Preview] --> B{Update Preview Triggered};
        B --> C{Is 'Disable Preview' Checked?};
        C -- Yes --> D[Show Simple List View in Table];
        C -- No --> E[Set Detailed Table Headers];
        E --> F[Start PredictionHandler Thread];
        F --> G[PredictionHandler Runs];
        G --> H[Slot: Populate Table with Detailed Results];

        I[User Clicks Start Processing] --> J{Get Output Path from UI LineEdit};
        J --> K[Validate/Create Output Path];
        K -- Path OK --> L[Start ProcessingHandler Thread];
        K -- Path Error --> M[Show Error Message];
        L --> N[ProcessingHandler Runs];
        N --> O[Update UI (Progress, Status)];

        P[User Clicks Browse...] --> Q[Show QFileDialog];
        Q --> R[Update Output Path LineEdit];
    end

    subgraph PredictionHandler [Background Thread]
        style PredictionHandler fill:#f9f,stroke:#333,stroke-width:2px
        F --> S{Use ThreadPoolExecutor};
        S --> T[Run _predict_single_asset Concurrently];
        T --> U[Collect Results];
        U --> V[Emit prediction_results_ready (Full List)];
        V --> H;
    end

    subgraph ProcessingHandler [Background Thread]
         style ProcessingHandler fill:#ccf,stroke:#333,stroke-width:2px
         L --> N;
    end