If you've written a Python library and you'd like to create a GUI application for it using PyQt (a set of Python bindings for The Qt Company’s Qt application framework), follow these steps:

1. **Set Up Your Environment**:
   - If you haven't already, install PyQt:
     ```bash
     pip install pyqt5 pyqt5-tools
     ```

2. **Design the GUI**:
   - You can use the Qt Designer (which comes with `pyqt5-tools`) to design your GUI. Once you've finished, save the design as a `.ui` file.
   - Convert the `.ui` file to a `.py` file:
     ```bash
     pyuic5 -x your_design.ui -o design.py
     ```

3. **Integrate Your Library**:
   - Import your library and the generated `design.py` file into a new Python script.
   - Create a class (e.g., `AppWindow`) that inherits from the main window class in `design.py` and `QMainWindow`.
   - In this class, connect your library functions to the GUI elements (e.g., buttons, input fields).

4. **Example**:
   Let's assume you've created a library `mylib.py` with a function `compute(x)` and you've created a GUI with an input field, a button, and a label.

   ```python
   import sys
   from PyQt5.QtWidgets import QApplication, QMainWindow
   import design
   import mylib

   class AppWindow(QMainWindow, design.Ui_MainWindow):
       def __init__(self):
           super().__init__()
           self.setupUi(self)
           self.computeButton.clicked.connect(self.on_compute)

       def on_compute(self):
           x = float(self.inputField.text())
           result = mylib.compute(x)
           self.resultLabel.setText(str(result))

   if __name__ == '__main__':
       app = QApplication(sys.argv)
       window = AppWindow()
       window.show()
       sys.exit(app.exec_())
   ```

5. **Run Your Application**:
   - Simply run the script you created in the previous step, and your GUI should appear, with your library's functionality integrated.

Remember that these steps are a general guideline, and the exact implementation might differ based on the specifics of your library and your desired GUI design.

Creating multi-window dynamic GUIs with PyQt involves handling multiple windows, dialogues, and interactions between them. Here's a basic guide to creating a multi-window application with PyQt:

1. **Set Up Your Environment**:
   - If you haven't already, install PyQt:
     ```bash
     pip install pyqt5 pyqt5-tools
     ```

2. **Design Multiple Windows**:
   - Use Qt Designer to design each of your windows. Save each design as a separate `.ui` file.
   - Convert each `.ui` file to a `.py` file using the `pyuic5` tool.

3. **Create Main Application File**:
   - Import the necessary PyQt5 modules and your generated `.py` GUI designs.
   - Create a main window class and initialize other window classes within it or initialize them when certain actions occur, like button clicks.

4. **Example**:
   Let's create a main window with a button that opens a secondary window:

   - Convert your main window `.ui` file and secondary window `.ui` file to `.py` files. Let's call them `main_window.py` and `second_window.py`.

   - Create a new Python script for your application:
     ```python
     import sys
     from PyQt5.QtWidgets import QApplication, QMainWindow, QDialog
     import main_window
     import second_window

     class MainApp(QMainWindow, main_window.Ui_MainWindow):
         def __init__(self):
             super().__init__()
             self.setupUi(self)
             self.openSecondWindowButton.clicked.connect(self.open_second_window)

         def open_second_window(self):
             self.second_window = SecondApp(self)
             self.second_window.show()

     class SecondApp(QDialog, second_window.Ui_Dialog):
         def __init__(self, parent=None):
             super(SecondApp, self).__init__(parent)
             self.setupUi(self)

     if __name__ == '__main__':
         app = QApplication(sys.argv)
         main_win = MainApp()
         main_win.show()
         sys.exit(app.exec_())
     ```

   In this example, the `MainApp` class corresponds to the main window of the application, and the `SecondApp` class corresponds to the secondary window. When the `openSecondWindowButton` button is clicked in the main window, the secondary window is opened.

5. **Dynamically Update Windows**:
   - To dynamically update content on windows, create methods inside your window classes that modify widgets. For example, if you want to update a label on `SecondApp` from `MainApp`, you could define a method in `SecondApp` and call it from `MainApp`.

6. **Inter-Window Communication**:
   - Use signals and slots for more complex interactions. For example, you can emit a signal from the secondary window when data is updated and connect it to a slot in the main window to take an action.

This guide gives you a basic structure to start with. As you develop more complex multi-window applications, you'll get into more advanced features of PyQt like layouts, model/view programming, custom widgets, etc.

To create an interactive window in PyQt that allows the user to write and modify text, you can use `QTextEdit`. Here's a simple example:

1. **Set Up Your Environment**:
   - If you haven't already, install PyQt:
     ```bash
     pip install pyqt5 pyqt5-tools
     ```

2. **Create the GUI**:
   - We'll create a window with a `QTextEdit` where users can type and modify text. We'll also add a button that when clicked, modifies the text in the `QTextEdit` to demonstrate programmatically changing the text.

Here's the code:

```python
import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QTextEdit, QPushButton, QVBoxLayout, QWidget

class TextApp(QMainWindow):
    def __init__(self):
        super().__init__()

        # Initialize the QTextEdit
        self.text_edit = QTextEdit(self)

        # Button to change text
        self.btn = QPushButton("Change Text", self)
        self.btn.clicked.connect(self.change_text)

        # Set layout
        layout = QVBoxLayout()
        layout.addWidget(self.text_edit)
        layout.addWidget(self.btn)

        container = QWidget()
        container.setLayout(layout)

        self.setCentralWidget(container)

        self.setWindowTitle("Interactive Text Window")
        self.setGeometry(100, 100, 400, 300)

    def change_text(self):
        """Change the text of the QTextEdit when the button is clicked"""
        self.text_edit.setText("The text has been changed!")

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = TextApp()
    window.show()
    sys.exit(app.exec_())
```

Run the above code. You'll see a window with a text area where you can write and modify text. Below the text area, there's a button that when clicked, changes the text in the text area.

This example demonstrates the basics. You can expand this further by adding more widgets and functionalities as per your requirements.

When building a larger PyQt application, a structured folder hierarchy can help manage complexity and improve readability. Here's a typical folder structure for a moderately complex PyQt application:

```
my_app/
│
├── main.py                 # The main script to start the application
│
├── ui/                     # Folder containing all GUI related .ui files created using Qt Designer
│   ├── main_window.ui
│   ├── settings_window.ui
│   ├── about_dialog.ui
│   └── ...
│
├── resources/              # Folder containing icons, images, and other resources
│   ├── icons/
│   │   ├── app_icon.png
│   │   └── ...
│   ├── images/
│   └── ...
│
├── generated/              # Folder containing generated .py files from .ui files
│   ├── ui_main_window.py
│   ├── ui_settings_window.py
│   ├── ui_about_dialog.py
│   └── ...
│
├── widgets/                # Custom widgets if any
│   ├── custom_widget1.py
│   └── custom_widget2.py
│
├── models/                 # MVC model components, database models, etc.
│   ├── data_model.py
│   └── ...
│
├── controllers/            # Logic to link UI and models
│   ├── main_controller.py
│   └── settings_controller.py
│
├── utilities/              # Any utility scripts or modules
│   ├── file_parser.py
│   ├── network_utils.py
│   └── ...
│
└── README.md
```

**Notes**:
- `main.py` is the main application file where the application is initialized and run.
- The `ui` folder stores the `.ui` files created using the Qt Designer. These are XML-like files describing the GUI layout.
- `resources` folder holds images, icons, or other assets that your application uses.
- The `generated` folder contains `.py` files that are the result of using the `pyuic5` tool to convert `.ui` files to Python code.
- `widgets` contains custom PyQt widgets that might be reused in different parts of the application.
- In an MVC (Model-View-Controller) architecture:
  - `models` would contain database models or data structures.
  - `controllers` would contain the application's logic.
- `utilities` could store any utility scripts or helper functions.

## Main Window

Below are the steps to create a main window in Qt Designer with a dash (`-`) and pipe (`|`) layout:

### Steps:

1. **Install Qt Designer**:
   If you haven't already, install `pyqt5-tools` which provides Qt Designer:
   ```bash
   pip install pyqt5-tools
   ```

   After installing, you can find the `designer.exe` executable in the directory like `site-packages/pyqt5_tools/`.

2. **Open Qt Designer**:
   Run `designer.exe` to launch Qt Designer.

3. **Create a New MainWindow**:
   - Click on `File` > `New`.
   - Choose `Main Window` and click `Create`.

4. **Set Up the Dash and Pipe Layout**:
   Imagine the layout as a grid where you want horizontal (`-`) separators and vertical (`|`) separators:

   ```
   +-------------------+
   |       Widget      |
   +-------------------+
   |       Widget      |
   +-------------------+
   |       Widget      |
   +-------------------+
   ```

   For this layout:

   a. Add a `QVBoxLayout` from the left-hand pane to the main window.
   b. Within the QVBoxLayout, drag and drop the widgets you want (like `QLabel`, `QTextEdit`, etc.).
   c. Between each widget, you can add horizontal spacers to simulate the `-` layout.
   d. For the `|` layout, within the QVBoxLayout, you can add a `QHBoxLayout` and place widgets side-by-side, separating them with vertical spacers.

5. **Adjust the Appearance**:
   - Adjust widget properties via the right-hand `Property Editor`. For example, change the text of a label or set the minimum size for a widget.

6. **Save Your Design**:
   - Click `File` > `Save` to save your design. This will save a `.ui` file which you can then convert to Python code using `pyuic5`.

7. **Convert the .ui File to .py**:
   After saving the design, use the following command to convert the `.ui` file to Python code:
   ```bash
   pyuic5 -x your_saved_file.ui -o output_file.py
   ```

8. **Integrate and Run in Python**:
   You can then integrate this generated Python code into your main application or run it as a standalone window.

This basic layout gives you a structure to work from. Qt Designer offers many tools and widgets for customization, allowing you to design complex and interactive GUIs as per your application's requirements.

Of course! Let's expand the functionality of the main window created in Qt Designer. For this example, we'll add:

1. A `QLineEdit` to enter text.
2. A `QPushButton` which, when clicked, updates a `QLabel` with the text entered in the `QLineEdit`.
3. A `QListWidget` that will store a history of all entered texts.

### Steps:

1. **Open Your .ui File in Qt Designer**:
   Load your previously created `.ui` file in Qt Designer.

2. **Add QLineEdit**:
   - Drag and drop a `QLineEdit` widget onto your main window. This will be used for text input.

3. **Add QPushButton**:
   - Drag and drop a `QPushButton` below the `QLineEdit`.
   - In the `Property Editor` on the right, set its text property to "Update".

4. **Add QLabel**:
   - Drag and drop a `QLabel` below the `QPushButton`.
   - This label will display the text entered in the `QLineEdit` when the button is pressed.

5. **Add QListWidget**:
   - Drag and drop a `QListWidget` below the `QLabel`.
   - This will store a history of all the texts that were entered and the button was pressed.

6. **Save the Design**:
   Save your updated design as a `.ui` file.

7. **Convert the .ui File to .py**:
   Convert the `.ui` file to Python code using:
   ```bash
   pyuic5 -x updated_file.ui -o updated_output.py
   ```

8. **Write the Logic in Python**:
   Open `updated_output.py` in your favorite editor and add the following functionality:

   ```python
   # ... (Other imports)
   from PyQt5.QtWidgets import QApplication

   # Assuming your class name is Ui_MainWindow, change if it's different
   class MainApp(QMainWindow, Ui_MainWindow):
       def __init__(self):
           super().__init__()
           self.setupUi(self)

           # Connect the button's click signal to our custom slot
           self.pushButton.clicked.connect(self.update_label_and_list)

       def update_label_and_list(self):
           # Get the text from QLineEdit
           entered_text = self.lineEdit.text()

           # Update the QLabel
           self.label.setText(entered_text)

           # Add the entered text to the QListWidget
           self.listWidget.addItem(entered_text)

   if __name__ == '__main__':
       app = QApplication(sys.argv)
       window = MainApp()
       window.show()
       sys.exit(app.exec_())
   ```

When you run this, you'll have an interactive window where you can type text into a `QLineEdit`, press a button to update a `QLabel` with that text, and also see a history of all entered texts in the `QListWidget`. This is just the beginning; you can continue to expand and customize the functionality and appearance based on your needs.

Absolutely! The top bar you're referring to is commonly known as a "menu bar". In PyQt, you can use the `QMenuBar` to create this functionality.

Let's expand the application by adding a menu bar with some dropdown menus:

### Steps:

1. **Open Your .ui File in Qt Designer**:

   Load your previously updated `.ui` file in Qt Designer.

2. **Add QMenuBar**:

   - In Qt Designer, the main window already comes with a menu bar by default. It's right at the top of the window.
   - Click on it and you will see `Type Here` placeholders.

3. **Create Menus**:

   - Click on the first `Type Here` on the menu bar, and type "File" to create a "File" menu.
   - A new `Type Here` appears below "File". Click on it and type "Open" to create an "Open" action.
   - Below "Open", type "Save" to create a "Save" action.
   - Click on the second `Type Here` on the menu bar and type "Edit" to create an "Edit" menu. Similarly, you can add items like "Copy", "Paste", etc.
   - Continue with this pattern to add any other menus or actions you need.

4. **Save the Design**:

   Save your updated design as a `.ui` file.

5. **Convert the .ui File to .py**:

   Convert the `.ui` file to Python code using:
   ```bash
   pyuic5 -x updated_file.ui -o updated_output.py
   ```

6. **Write the Logic in Python**:

   Open `updated_output.py` in your favorite editor and add functionality for the menu actions:

   ```python
   # ... (Other imports and previous code)

   class MainApp(QMainWindow, Ui_MainWindow):
       def __init__(self):
           super().__init__()
           self.setupUi(self)

           # Connect the button's click signal and previous functionalities
           self.pushButton.clicked.connect(self.update_label_and_list)

           # Connect the menu actions
           self.actionOpen.triggered.connect(self.open_file)
           self.actionSave.triggered.connect(self.save_file)
           # Add connections for other actions similarly...

       def update_label_and_list(self):
           # ... (Previous code)

       def open_file(self):
           # Here you can add code to handle file opening, e.g., using QFileDialog
           pass

       def save_file(self):
           # Here you can add code to handle file saving
           pass

       # Define other methods for the other actions similarly...

   if __name__ == '__main__':
       # ... (Previous code)
   ```

When you run the updated application, you'll have a top menu bar with dropdown menus and actions. You can connect each action to its corresponding slot (function/method) to perform the desired operations, such as opening or saving files, editing content, etc.

The use of Qt Designer makes it simple to visually design your UI and expand its functionality, while PyQt allows for easy integration of these designs with Python for adding logic and interactivity.

Certainly! Building an expandable sidebar with settings for configuring plain text to SSML using the Azure Speech API can be quite an extensive task. To simplify things, I'll outline the process and provide details on how to build some key components.

### Steps:

1. **Open Your .ui File in Qt Designer**:

   Load your previously updated `.ui` file in Qt Designer.

2. **Add QDockWidget**:

   A `QDockWidget` provides a floating or dockable window to host widgets, which can be great for sidebars.

   - Drag and drop a `QDockWidget` to your main window.
   - Set its title to "SSML Configuration".

3. **Add QTreeWidget to QDockWidget**:

   To create an expandable settings list, we'll use a `QTreeWidget`.

   - Drag and drop a `QTreeWidget` inside the `QDockWidget`.
   - Using the `QTreeWidget` editor (right-click on it), create tree items for configurations like "Neural Voice", "Pitch", "Speaking Rate", etc. For some items, you may want to add child items. For instance, under "Pitch", you might have options like "High", "Medium", and "Low".

4. **Create Widgets for Configuration**:

   Depending on what type of setting a user clicks on, you might want to show different widgets, like `QComboBox` for dropdown selections or `QSlider` for adjusting values. These can be added to the main window and made visible or hidden based on user selections.

5. **Save & Convert**:

   Save the updated design and convert it to Python code.

6. **Python Logic**:

   In your Python code, handle the sidebar interactions:

   - When a user clicks on a `QTreeWidget` item, show the appropriate widget to adjust the setting.
   - For instance, if they click on "Neural Voice", show a `QComboBox` populated with neural voice options.
   - When the user adjusts settings, construct or modify the SSML string accordingly.

7. **Azure Speech API Integration**:

   Assuming you have set up Azure Speech SDK for Python:

   ```bash
   pip install azure-cognitiveservices-speech
   ```

   Use the SDK to send the constructed SSML string to Azure for conversion to speech:

   ```python
   import azure.cognitiveservices.speech as speechsdk

   def text_to_speech(ssml_string):
       speech_config = speechsdk.SpeechConfig(subscription="YourAzureSubscriptionKey", region="YourAzureRegion")
       audio_config = speechsdk.AudioConfig(filename="output_audio.mp3")
       synthesizer = speechsdk.SpeechSynthesizer(speech_config=speech_config, audio_config=audio_config)
       result = synthesizer.speak_ssml_async(ssml_string).get()

       # Handle the result (e.g., check if the synthesis was successful)
   ```

8. **Connect Sidebar to Azure Integration**:

   As the user adjusts settings and finalizes the SSML configuration, add a "Convert to Speech" button. When pressed, this will convert the constructed SSML string to speech using the Azure Speech API.

This is a high-level guide and doesn't cover every detailed aspect (like error handling with the Azure API, detailed SSML construction, etc.). However, it should give you a clear direction on how to build the expandable sidebar for SSML configuration and integrate it with Azure Speech API.

Absolutely. To better structure this, let's outline a couple of key functionalities and work through them step by step:

1. **SSML Preview**:

   Add a `QTextEdit` that provides a live SSML preview based on the sidebar configurations.

2. **Play Audio**:

   Allow users to play the generated speech audio directly within the application.

### Steps:

1. **Open Your .ui File in Qt Designer**:

   Load your updated `.ui` file in Qt Designer.

2. **Add SSML Preview**:

   - Drag and drop a `QTextEdit` to a suitable area on your main window.
   - Set its `readOnly` property to `True` so users can't edit it directly.
   - Label it "SSML Preview".

3. **Add Play Audio Button**:

   - Drag and drop a `QPushButton` below the SSML preview or in another appropriate location.
   - Label it "Play Audio".

4. **Save & Convert**:

   Save the updated design and convert it to Python code.

5. **Python Logic**:

   Extend your Python application with these new functionalities:

   ```python
   # ... (Previous imports and code)

   class MainApp(QMainWindow, Ui_MainWindow):
       def __init__(self):
           # ... (Previous initializations)

           # Connect the play audio button
           self.playAudioButton.clicked.connect(self.play_audio)

           # Also, whenever a user adjusts SSML settings on the sidebar,
           # update the SSML preview. This will be custom based on how you've set up your sidebar.
           # self.update_ssml_preview()

       def update_ssml_preview(self):
           # Construct the SSML based on user configurations.
           ssml_string = "<speak version='1.0' ...>"  # Construct it dynamically
           self.ssmlPreviewTextEdit.setPlainText(ssml_string)

       def play_audio(self):
           # Use the Azure SDK to convert SSML to audio, then play it.
           # Assuming you saved the audio to "output_audio.mp3":
           import os
           os.system("start output_audio.mp3")

   # ... (Rest of the code)
   ```

   Note: The `os.system` command will work for playing audio on most systems, but for more advanced audio playback controls (like pause, stop, volume control), consider using a library like `pygame`.

6. **Advanced Audio Controls (Optional)**:

   If you want to add advanced audio controls (play, pause, stop, volume), you can use the `pygame` library:

   ```bash
   pip install pygame
   ```

   Then, extend your app's functionality:

   ```python
   import pygame

   class MainApp(QMainWindow, Ui_MainWindow):
       # ...

       def play_audio(self):
           pygame.mixer.init()
           pygame.mixer.music.load("output_audio.mp3")
           pygame.mixer.music.play()

       def pause_audio(self):
           pygame.mixer.music.pause()

       def stop_audio(self):
           pygame.mixer.music.stop()
   ```

   Remember to add corresponding buttons for pause and stop, and connect their signals to these methods.

This enhancement provides users with a live preview of the SSML they're configuring, and lets them play the resulting speech audio directly within the application, enhancing the overall user experience.

Adding a second window to an application usually implies a distinct or advanced set of functionalities that wouldn't fit appropriately on the main window or would clutter it. Given the context of your application, which involves configuring SSML for Azure's Speech API, here are some ideas for a secondary window:

1. **Advanced SSML Editor**:
   - A detailed SSML editor where users can manually edit and format SSML tags.
   - Syntax highlighting for SSML.
   - Validate the SSML to ensure it's correctly formatted.

2. **Speech Configurations**:
   - Set specific Azure Speech API settings.
   - Authentication configurations: Allow users to input and save their Azure API keys or other credentials.
   - Speech settings like region, endpoint, etc.

3. **Speech History and Cache**:
   - Display a history of past SSML-to-speech conversions.
   - Cache certain SSML settings and speech outputs for quick access.
   - Allow users to quickly replay or re-export past conversions.

4. **Feedback & Analysis**:
   - Visualizations of speech properties (like pitch, frequency, etc.).
   - Allow users to provide feedback on generated speech and store/save feedback.

5. **Tutorials & Help**:
   - A window with guides, FAQ, or even video tutorials on SSML, Azure Speech API, and how to use your application effectively.

6. **Bulk Processing**:
   - Allow users to batch convert multiple texts to speech.
   - Configure different settings for each text or apply a common setting to all.

### How to Implement the Secondary Window:

1. **Design the Window in Qt Designer**:
   - Create a new window form in Qt Designer.
   - Add widgets and layouts as per the chosen functionality.
   - Save this design as a separate `.ui` file, e.g., `secondary_window.ui`.

2. **Convert .ui to .py**:
   ```bash
   pyuic5 -x secondary_window.ui -o secondary_window.py
   ```

3. **Integration**:
   In your main application's Python code:

   ```python
   from secondary_window import Ui_SecondaryWindow

   class SecondaryApp(QMainWindow, Ui_SecondaryWindow):
       def __init__(self):
           super().__init__()
           self.setupUi(self)
           # Add logic for the widgets on this secondary window

   class MainApp(QMainWindow, Ui_MainWindow):
       def __init__(self):
           # ... (previous initializations)

           # Add a button or menu action to open the secondary window
           self.openSecondaryWindowButton.clicked.connect(self.open_secondary)

       def open_secondary(self):
           self.secondary_window = SecondaryApp()
           self.secondary_window.show()
   ```

This modular approach keeps the main functionality separated from the advanced or additional features, resulting in a cleaner and more intuitive user experience.

Creating a cryptographically secure section, especially when dealing with API keys and credentials, is of utmost importance. Here's how you can build and ensure this section's security:

### 1. Design the Configuration Window in Qt Designer:

- Start a new form in Qt Designer.
- Add input fields (`QLineEdit` widgets) for:
  - Azure API keys
  - Region
  - Endpoint, etc.
- For the API keys, use the `QLineEdit` property `echoMode` and set it to `Password` to hide input.
- Save this design as `config_window.ui`.

### 2. Convert .ui to .py:

```bash
pyuic5 -x config_window.ui -o config_window.py
```

### 3. Implement Cryptographic Security:

We'll use the `cryptography` library for Python:

```bash
pip install cryptography
```

Use Fernet symmetric encryption to securely encrypt and store sensitive data:

```python
from cryptography.fernet import Fernet

# Generate a key. Store this securely! If you lose it, you can't decrypt your data.
key = Fernet.generate_key()

cipher = Fernet(key)

# Encrypting data
def encrypt_data(data):
    encrypted_data = cipher.encrypt(data.encode())
    return encrypted_data

# Decrypting data
def decrypt_data(encrypted_data):
    decrypted_data = cipher.decrypt(encrypted_data).decode()
    return decrypted_data
```

### 4. Integrate with Your Application:

```python
from config_window import Ui_ConfigWindow
from PyQt5.QtWidgets import QMainWindow, QMessageBox

class ConfigApp(QMainWindow, Ui_ConfigWindow):
    def __init__(self):
        super().__init__()
        self.setupUi(self)

        # Load saved settings (if they exist) and decrypt them for display
        self.load_saved_settings()

        # Connect save button
        self.saveButton.clicked.connect(self.save_settings)

    def load_saved_settings(self):
        # Load encrypted data from file or database
        # For this example, let's assume a simple file-based storage
        try:
            with open("encrypted_settings.dat", "rb") as file:
                encrypted_data = file.read()
                decrypted_data = decrypt_data(encrypted_data)

                # Split the decrypted data and populate the fields (for simplicity, using ':' delimiter)
                api_key, region, endpoint = decrypted_data.split(':')
                self.apiKeyLineEdit.setText(api_key)
                self.regionLineEdit.setText(region)
                self.endpointLineEdit.setText(endpoint)
        except:
            pass  # Handle exception (e.g., file not found, decryption error, etc.)

    def save_settings(self):
        # Fetch input from line edits, then encrypt and save
        api_key = self.apiKeyLineEdit.text()
        region = self.regionLineEdit.text()
        endpoint = self.endpointLineEdit.text()

        combined_data = f"{api_key}:{region}:{endpoint}"
        encrypted_data = encrypt_data(combined_data)

        with open("encrypted_settings.dat", "wb") as file:
            file.write(encrypted_data)

        QMessageBox.information(self, "Success", "Settings saved securely!")

# In your main application, create an instance of ConfigApp and show it when required.
```

### Security Considerations:

1. **Key Storage**: The encryption key is crucial. If you lose it, you can't recover your data. Don't hard-code it. Consider using secure key management solutions or services like Azure Key Vault.

2. **Local Storage**: Even with encryption, avoid storing sensitive data (like API keys) locally if possible. If you have to, ensure the storage is as secure as possible.

3. **Updates & Rotation**: Allow users to update keys, and consider key rotation strategies for added security.

4. **Transit Security**: Always use HTTPS/SSL when sending/retrieving sensitive data over the network.

5. **Input Validation**: Always validate user inputs to prevent any form of malicious input.

6. **Warning**: The simple file-based storage used in the example is for demonstration purposes. For a production application, consider a more secure storage mechanism, such as a secured database or cloud-based storage with encryption at rest.

To implement a bulk processing feature on the secondary window, you'll have to consider both the GUI design and the backend logic for processing.

### 1. Design in Qt Designer:

**On the secondary window**:

- Add a `QTableWidget` for users to add multiple texts. You can have columns like `Text`, `Voice`, `Speed`, `Volume`, etc.
- Add a `QPushButton` for users to add a new row (text entry) to the table.
- Add another `QPushButton` for starting the batch conversion process.
- Optional: Add a `QGroupBox` with common settings that, when set, can be applied to all entries.

Save the UI design as `bulk_processing.ui`.

### 2. Convert .ui to .py:

```bash
pyuic5 -x bulk_processing.ui -o bulk_processing.py
```

### 3. Python Backend Integration:

```python
from bulk_processing import Ui_BulkProcessing
from PyQt5.QtWidgets import QMainWindow, QTableWidgetItem

class BulkProcessingApp(QMainWindow, Ui_BulkProcessing):
    def __init__(self):
        super().__init__()
        self.setupUi(self)

        # Connect buttons
        self.addRowButton.clicked.connect(self.add_row)
        self.startProcessingButton.clicked.connect(self.process_texts)

    def add_row(self):
        row_position = self.tableWidget.rowCount()
        self.tableWidget.insertRow(row_position)

        # Example: Initializing a row with default values
        self.tableWidget.setItem(row_position, 0, QTableWidgetItem("Text Here"))
        self.tableWidget.setItem(row_position, 1, QTableWidgetItem("Default Voice"))

    def process_texts(self):
        total_rows = self.tableWidget.rowCount()

        for row in range(total_rows):
            text = self.tableWidget.item(row, 0).text()
            voice = self.tableWidget.item(row, 1).text()
            # Fetch other settings similarly

            # Use the Azure Speech API to process each text
            # You can choose to apply individual settings or common settings as needed

            # Save or play the generated audio

```

### 4. Integrate with Main Application:

Assuming your main application has a button or an option to open the bulk processing window:

```python
class MainApp(QMainWindow, Ui_MainWindow):
    # ... other initializations ...

    def open_bulk_processing(self):
        self.bulk_window = BulkProcessingApp()
        self.bulk_window.show()

    # Connect the function to a button or menu action in your main application.
    # Example:
    # self.bulkProcessingButton.clicked.connect(self.open_bulk_processing)
```

### Considerations:

1. **Progress Feedback**: If processing many texts, it may take some time. Consider adding a `QProgressBar` or similar feedback mechanism to inform users of the progress.

2. **Error Handling**: Implement error handling, especially for potential API issues or if user input is invalid.

3. **Storage**: Decide on how you want to save or present the generated audio. Options include saving to files, playing immediately, or caching for later use.

4. **Concurrency**: If the processing is slow and you want to improve performance, consider using threads or Python's `asyncio` to handle multiple conversions concurrently. However, remember to ensure GUI operations remain on the main thread. Use signals/slots mechanism in PyQt to communicate between threads and the main GUI.
