app.py

import gradio as gr
import os
import asyncio
from openai import AsyncOpenAI
from functools import partial # For handle_script_processing

# Import UI creation functions and constants
from ui_layout import (
    create_main_input_components, create_speaker_config_components,
    create_action_and_output_components, create_examples_ui,
    TTS_MODELS_AVAILABLE, MODEL_DEFAULT_ENV
)

# Import event handler functions
from event_handlers import (
    handle_script_processing, handle_calculate_cost,
    update_model_controls_visibility, update_speaker_config_method_visibility,
    load_refresh_per_speaker_ui
)

# --- Application Secrets and Global Client ---
OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
NSFW_API_URL_TEMPLATE = os.getenv("NSFW_API_URL_TEMPLATE")
MODEL_DEFAULT_FROM_ENV = os.getenv("MODEL_DEFAULT", MODEL_DEFAULT_ENV)

# Validate MODEL_DEFAULT_FROM_ENV or use hardcoded default
EFFECTIVE_MODEL_DEFAULT = MODEL_DEFAULT_FROM_ENV if MODEL_DEFAULT_FROM_ENV in TTS_MODELS_AVAILABLE else MODEL_DEFAULT_ENV

async_openai_client = None
if not OPENAI_API_KEY:
    try:
        # Attempt to load from Hugging Face Hub secrets if not in env
        from huggingface_hub import HfApi
        api = HfApi()
        space_id = os.getenv("SPACE_ID") # Provided by HF Spaces
        if space_id:
            secrets = api.get_space_secrets(repo_id=space_id)
            OPENAI_API_KEY = secrets.get("OPENAI_API_KEY")
            NSFW_API_URL_TEMPLATE = secrets.get("NSFW_API_URL_TEMPLATE", NSFW_API_URL_TEMPLATE)
            MODEL_DEFAULT_FROM_HUB = secrets.get("MODEL_DEFAULT", EFFECTIVE_MODEL_DEFAULT)
            EFFECTIVE_MODEL_DEFAULT = MODEL_DEFAULT_FROM_HUB if MODEL_DEFAULT_FROM_HUB in TTS_MODELS_AVAILABLE else EFFECTIVE_MODEL_DEFAULT
            print("Loaded secrets from Hugging Face Hub.")
    except Exception as e:
        print(f"Could not retrieve secrets from Hugging Face Hub: {e}. OPENAI_API_KEY might be missing.")

if OPENAI_API_KEY:
    async_openai_client = AsyncOpenAI(api_key=OPENAI_API_KEY)
else:
    print("CRITICAL ERROR: OPENAI_API_KEY secret is not set. The application will not function properly.")


# --- Gradio Application UI and Logic ---
with gr.Blocks(theme=gr.themes.Soft()) as demo:
    gr.Markdown("# Dialogue Script to Speech (OpenAI TTS) - Refactored")
    if not OPENAI_API_KEY or not async_openai_client:
        gr.Markdown("<h3 style='color:red;'>⚠️ Warning: OPENAI_API_KEY not set or invalid. Audio generation will fail. Please configure it in your Space settings.</h3>")

    # Central state for detailed speaker configurations
    speaker_configs_state = gr.State({}) # This is crucial for dynamic UI

    # --- Define UI Components by calling layout functions ---
    (script_input, tts_model_dropdown, pause_input,
     global_speed_input, global_instructions_input) = create_main_input_components(EFFECTIVE_MODEL_DEFAULT)

    (speaker_config_method_dropdown, single_voice_group, global_voice_dropdown,
     detailed_per_speaker_ui_group, load_per_speaker_ui_button,
     dynamic_speaker_ui_area) = create_speaker_config_components()

    (calculate_cost_button, generate_button, cost_output,
     individual_lines_zip_output, merged_dialogue_mp3_output,
     status_output) = create_action_and_output_components()

    # --- Event Wiring ---

    # When TTS model changes, update visibility of global speed/instructions & refresh dynamic UI
    tts_model_dropdown.change(
        fn=update_model_controls_visibility,
        inputs=[tts_model_dropdown, script_input, speaker_configs_state, speaker_configs_state],
        outputs=[global_speed_input, global_instructions_input, dynamic_speaker_ui_area, speaker_configs_state]
    )

    # When speaker config method changes, update visibility of relevant UI groups
    speaker_config_method_dropdown.change(
        fn=update_speaker_config_method_visibility,
        inputs=[speaker_config_method_dropdown],
        outputs=[single_voice_group, detailed_per_speaker_ui_group]
    )
    
    # Button to load/refresh the detailed per-speaker UI configurations
    load_per_speaker_ui_button.click(
        fn=load_refresh_per_speaker_ui,
        inputs=[script_input, speaker_configs_state, tts_model_dropdown, speaker_configs_state], 
        outputs=[dynamic_speaker_ui_area, speaker_configs_state]
    )
    
    # Calculate cost button
    calculate_cost_button.click(
        fn=handle_calculate_cost,
        inputs=[script_input, tts_model_dropdown],
        outputs=[cost_output]
    )
    
    # Generate audio button
    # Use functools.partial to pass fixed arguments like API key and client to the handler
    # Gradio inputs will be appended to these fixed arguments when the handler is called.
    generate_button_fn = partial(handle_script_processing, OPENAI_API_KEY, async_openai_client, NSFW_API_URL_TEMPLATE)
    generate_button.click(
        fn=generate_button_fn,
        inputs=[
            script_input, tts_model_dropdown, pause_input,
            speaker_config_method_dropdown, global_voice_dropdown,
            speaker_configs_state, # The gr.State object itself
            global_speed_input, global_instructions_input
        ],
        outputs=[individual_lines_zip_output, merged_dialogue_mp3_output, status_output]
    )

    # --- Examples UI ---
    example_inputs_list = [
        script_input, tts_model_dropdown, pause_input,
        speaker_config_method_dropdown, global_voice_dropdown,
        speaker_configs_state, 
        global_speed_input, global_instructions_input
    ]
    
    example_outputs_list = [individual_lines_zip_output, merged_dialogue_mp3_output, status_output]
    
    # Make examples runnable
    example_process_fn = partial(handle_script_processing, OPENAI_API_KEY, async_openai_client, NSFW_API_URL_TEMPLATE)
    
    _ = create_examples_ui(
        inputs_for_examples=example_inputs_list,
        process_fn=example_process_fn if OPENAI_API_KEY else None, # Only make runnable if API key exists
        outputs_for_examples=example_outputs_list if OPENAI_API_KEY else None
    )


# --- Launch ---
if __name__ == "__main__":
    if os.name == 'nt':
        asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
    demo.queue().launch(debug=True, share=False)