app.py

import os
import html
import math
import re
import struct
import wave
import numpy as np
import gradio as gr
import time
from pathlib import Path

from tts import (
    cancel_pregeneration,
    generate_audio_stream,
    get_pregeneration_status,
    pregenerate_story_audio,
    split_into_chunks,
)
from inference import transcribe_audio, answer_story_question
from inference_lfm import answer_question_audio
from qa_flow import build_qa_response, claim_audio_submission, release_audio_submission
from runtime_config import SAMPLE_SOUNDS_DIR, gradio_allowed_paths
from voice_clone import load_default_profile, list_saved_profiles

# Generate relaxing audio chime waveforms procedurally
# This runs fully client/server-side with standard Python, eliminating mock limits or Torch wait times
def generate_chimes_wav(filename, duration=120, melody_type="lullaby"):
    sample_rate = 16000
    n_samples = int(duration * sample_rate)

    with wave.open(str(filename), 'wb') as wav_file:
        wav_file.setnchannels(1)
        wav_file.setsampwidth(2)
        wav_file.setframerate(sample_rate)

        # Pentatonic cozy scales
        if melody_type == "lullaby":
            notes = [261.63, 293.66, 329.63, 392.00, 440.00] # C4, D4, E4, G4, A4
        elif melody_type == "adventure":
            notes = [196.00, 246.94, 293.63, 329.63, 392.00] # G3, B3, D4, E4, G4
        else:
            notes = [220.00, 261.63, 293.66, 329.63, 392.00] # A3, C4, D4, E4, G4

        for i in range(n_samples):
            # cycle notes based on melody speed
            note_speed = sample_rate * 1.5 if melody_type == "lullaby" else sample_rate * 1.2
            note_idx = int((i / note_speed) % len(notes))
            freq = notes[note_idx]

            # envelope to prevent crackles
            sample_in_note = i % int(note_speed)
            envelope = 1.0
            if sample_in_note < 1200: # attack
                envelope = sample_in_note / 1200
            else: # decay
                decay_length = note_speed - 1200
                envelope = max(0.0, 1.0 - (sample_in_note - 1200) / decay_length)

            # Synthesize voice-harmonic chime
            val = math.sin(2 * math.pi * freq * i / sample_rate)
            val += 0.45 * math.sin(2 * math.pi * (freq * 1.5) * i / sample_rate)
            val += 0.25 * math.sin(2 * math.pi * (freq * 2.0) * i / sample_rate)
            val = val / 1.7 * envelope

            packed_val = struct.pack('<h', int(val * 16384))
            wav_file.writeframes(packed_val)

# Generate a short placeholder chime for the preview widget's initial value
_preview_chime_path = SAMPLE_SOUNDS_DIR / "cloned_preview.wav"
if not _preview_chime_path.exists():
    generate_chimes_wav(_preview_chime_path, duration=15, melody_type="lullaby")

COVERS_DIR = Path(__file__).parent / "assets" / "covers"

def cover_path(slug: str) -> str:
    p = COVERS_DIR / f"{slug}.png"
    return f"/gradio_api/file={p.resolve().as_posix()}"

def load_books_from_stories(stories_dir="stories"):
    books = []
    story_files = sorted(
        f for f in os.listdir(stories_dir) if f.endswith(".txt")
    ) if os.path.isdir(stories_dir) else []

    for i, filename in enumerate(story_files):
        title = filename.replace(".txt", "").replace("_", " ")
        slug = filename.replace(".txt", "")
        synopsis = ""
        try:
            with open(os.path.join(stories_dir, filename), encoding="utf-8") as f:
                lines = [l.strip() for l in f.readlines() if l.strip()]
                synopsis = " ".join(lines[1:4]) if len(lines) > 1 else lines[0] if lines else ""
        except Exception:
            pass

        books.append({
            "id": str(i + 1),
            "title": title,
            "author": "Public Domain",
            "cover_url": cover_path(slug),
            "voice_name": "Mom's Voice",
            "duration": 0,
            "elapsed_time": 0,
            "synopsis": synopsis,
            "category": "Children's Story",
            "is_cloned": False,
            "percentage": 0,
            "audio_path": None,
            "story_path": os.path.join(stories_dir, filename),
        })
    return books

mock_books = load_books_from_stories()

mock_voices = [
    {
        "id": "v1",
        "name": "Mom's Voice",
        "avatar_url": "👩‍🦳",
        "description": "Warm, soft, with a natural soothing cadence. Best for bedtime stories.",
        "gender": "Female",
        "created_date": "2026-06-01",
        "status": "ready"
    },
    {
        "id": "v2",
        "name": "Grandpa Joseph",
        "avatar_url": "👴",
        "description": "Deep, resonant, with an occasional comforting chuckle. Perfect for classic adventure stories.",
        "gender": "Male",
        "created_date": "2026-06-03",
        "status": "ready"
    },
    {
        "id": "v3",
        "name": "Aunt Sarah",
        "avatar_url": "👩",
        "description": "Bubbly, expressive, brilliant at acting out funny character voices.",
        "gender": "Female",
        "created_date": "2026-06-06",
        "status": "processing"
    }
]

with open(os.path.join(os.path.dirname(__file__), "static", "style.css"), encoding="utf-8") as _f:
    css_code = _f.read()

def generate_dashboard_html(books_list):
    if not books_list:
        return "<div style='padding:40px;text-align:center;color:#FAF7F2;'>No stories found. Add .txt files to the stories/ folder.</div>"
    featured = books_list[0]
    others = books_list[1:]
    featured_js_title = featured['title'].replace("'", "\\'").replace('"', '\\"')

    html = f"""
    <div style="margin-bottom: 24px;">
        <span style="font-size: 11px; text-transform: uppercase; letter-spacing: 2px; color: #f5841f; font-weight: 600;">Welcome Back, Sarah</span>
        <h2 class="serif-header" style="font-size: 28px; margin-top: 4px; margin-bottom: 16px;">Explore Your Warm Audiobook Shelves</h2>
    </div>

    <!-- Hero Spotlight Section -->
    <div class="hero-spotlight" style="display: flex; flex-direction: row; gap: 32px; align-items: center; margin-bottom: 32px; flex-wrap: wrap; cursor: pointer;" onclick="
        var tabs = document.querySelectorAll('button[role=tab]');
        if (tabs.length > 1) {{ tabs[1].click(); }}
        setTimeout(function() {{
            var radios = document.querySelectorAll('.library-book-selector input[type=radio]');
            radios.forEach(function(r) {{
                if(r.value === '{featured_js_title}') {{
                    r.checked = true;
                    r.dispatchEvent(new Event('input', {{bubbles: true}}));
                    r.dispatchEvent(new Event('change', {{bubbles: true}}));
                }}
            }});
        }}, 300);
    ">
        <div style="flex: 1; min-width: 200px; max-width: 280px; text-align: center;">
            <img src="{featured['cover_url']}" style="width: 180px; height: 260px; object-fit: cover; border-radius: 16px; box-shadow: 0 8px 24px rgba(0,0,0,0.3); transform: rotate(-2deg);" referrerPolicy="no-referrer" />
        </div>
        <div style="flex: 2; min-width: 300px; display: flex; flex-direction: column; justify-content: space-between; gap: 16px;">
            <div>
                <span class="badge-featured" style="margin-bottom: 8px;">Featured Clone</span>
                <h3 class="serif-header" style="color: white !important; font-size: 28px; margin: 4px 0;">{featured['title']}</h3>
                <p style="color: #6f6257;">by <span style="font-style: italic; color: #ddc1b0;">{featured['author']}</span></p>
                <p style="color: #cbd5e1; font-size: 13.5px; line-height: 1.6; margin-top: 8px;">{featured['synopsis']}</p>
            </div>

            <div style="display: flex; gap: 12px; flex-wrap: wrap; font-size: 12px; color: #e2e8f0;">
                <span style="background: rgba(255,255,255,0.1); padding: 4px 10px; border-radius: 8px;">⏱️ 20 Min Remaining</span>
                <span style="background: rgba(255,255,255,0.1); padding: 4px 10px; border-radius: 8px; font-weight: 600; color: #ffd3a6;">🎙️ Narrator: {featured['voice_name']}</span>
                <span style="background: rgba(255,255,255,0.1); padding: 4px 10px; border-radius: 8px;">⭐ Editorial Spotlight</span>
            </div>
        </div>
    </div>

    <div>
        <h4 class="serif-header" style="font-size: 20px; margin-bottom: 16px;">Continue Reading with Channeled Voices</h4>
        <div class="book-shelf-grid">
    """

    for bk in books_list:
        js_safe_title = bk['title'].replace("'", "\\'").replace('"', '\\"')
        html += f"""
        <div class="shelf-card" style="cursor: pointer;" onclick="
            // Switch to My Library tab (2nd tab button)
            var tabs = document.querySelectorAll('button[role=tab]');
            if (tabs.length > 1) {{ tabs[1].click(); }}
            // Select book in hidden radio
            setTimeout(function() {{
                var radios = document.querySelectorAll('.library-book-selector input[type=radio]');
                radios.forEach(function(r) {{
                    if(r.value === '{js_safe_title}') {{
                        r.checked = true;
                        r.dispatchEvent(new Event('input', {{bubbles: true}}));
                        r.dispatchEvent(new Event('change', {{bubbles: true}}));
                    }}
                }});
            }}, 300);
        ">
            <div>
                <img src="{bk['cover_url']}" class="cover-image" referrerPolicy="no-referrer" />
            </div>
            <div style="display: flex; flex-direction: column; justify-content: space-between; flex: 1; min-width: 0;">
                <div>
                    <div style="display: flex; justify-content: space-between; font-size: 10px; font-weight: 700; color: #f5841f;">
                        <span>{bk['category']}</span>
                        <span>{bk['percentage']}%</span>
                    </div>
                    <h5 class="serif-header" style="font-size: 14px; margin: 4px 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;">{bk['title']}</h5>
                    <p style="font-size: 11.5px; color: #6f6257; margin-bottom: 8px;">by {bk['author']}</p>
                </div>
                <div>
                    <div class="progress-bar-bg" style="margin-bottom: 6px;">
                        <div class="progress-bar-fill" style="width: {bk['percentage']}%"></div>
                    </div>
                    <div style="display: flex; justify-content: space-between; font-size: 11px; color: #6f6257;">
                        <span style="overflow: hidden; text-overflow: ellipsis; white-space: nowrap;">🎙️ {bk['voice_name']}</span>
                    </div>
                </div>
            </div>
        </div>
        """

    html += """
        </div>
    </div>
    """
    return html


def generate_library_html(books_list, query="", category_filt="All", empty_mode=False):
    if empty_mode:
        return """
        <div style="display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 64px 16px; text-align: center; max-width: 440px; margin: 0 auto;">
            <div style="position: relative; width: 90px; height: 90px; border-radius: 50%; background: #ede8e3; border: 1px dashed #ddc1b0; display: flex; align-items: center; justify-content: center; margin-bottom: 24px;">
                <span style="font-size: 32px;">📚</span>
                <span style="position: absolute; font-size: 20px; bottom: -4px; right: -4px;">🎙️</span>
            </div>
            <h3 class="serif-header" style="font-size: 22px; margin-bottom: 8px;">Your Bookshelf is Waiting to be Voiced</h3>
            <p style="font-size: 13.5px; color: #6f6257; line-height: 1.5; margin-bottom: 24px;">
                Choose a comforting companion, clone their warm voice, and hear any classical or modern tale come to life immediately.
            </p>
            <div style="display: flex; gap: 12px; width: 100%;">
                <span style="flex: 1; padding: 12px; background: #944a00; color: white; border-radius: 12px; font-weight: 700; font-size: 13px;">Use 'Clone Voice' tab to craft a companion</span>
            </div>
        </div>
        """

    filtered = []
    for bk in books_list:
        match_query = (query.lower() in bk["title"].lower()) or (query.lower() in bk["author"].lower()) or (query.lower() in bk["voice_name"].lower())
        match_cat = True

        if category_filt == "In Progress":
            match_cat = 0 < bk["percentage"] < 100
        elif category_filt == "Completed":
            match_cat = bk["percentage"] == 100

        if match_query and match_cat:
            filtered.append(bk)

    if len(filtered) == 0:
        return """
        <div style="text-align: center; padding: 48px; border: 1px dashed #ebdccb; border-radius: 16px;">
            <span style="font-size: 28px;">🔍</span>
            <p style="font-size: 14px; color: #6f6257; margin-top: 8px;">No audiobooks match your search criteria.</p>
        </div>
        """

    html_out = """<div class="book-shelf-grid">"""
    for bk in filtered:
        safe_title = html.escape(bk['title'])
        js_safe_title = bk['title'].replace("'", "\\'").replace('"', '\\"')
        html_out += f"""
        <div class="shelf-card group" style="flex-direction: column; gap: 0; padding: 0; overflow: hidden; cursor: pointer;" onclick="
            var radios = document.querySelectorAll('.library-book-selector input[type=radio]');
            radios.forEach(function(r) {{
                if(r.value === '{js_safe_title}') {{
                    r.checked = true;
                    r.dispatchEvent(new Event('input', {{bubbles: true}}));
                    r.dispatchEvent(new Event('change', {{bubbles: true}}));
                }}
            }});
        ">
            <div style="position: relative; aspect-ratio: 3/4; overflow: hidden; height: 200px;">
                <img src="{bk['cover_url']}" style="width: 100%; height: 100%; object-fit: cover;" referrerPolicy="no-referrer" />
                <div style="position: absolute; top: 12px; right: 12px; background: rgba(255,255,255,0.95); padding: 4px 10px; border-radius: 8px; font-weight: 700; font-size: 11px; border: 1px solid #ebdccb; color: #1c1c19;">
                    {bk['percentage']}%
                </div>
                <div style="position: absolute; bottom: 0; left: 0; right: 0; background: linear-gradient(0deg, rgba(0,0,0,0.85) 0%, rgba(0,0,0,0) 100%); padding: 12px; color: white;">
                    <span style="font-size: 9px; text-transform: uppercase; letter-spacing: 1.5px; font-weight: 700; color: #f5841f;">{bk['category']}</span>
                    <h5 class="serif-header" style="color: white !important; font-size: 15px; margin: 2px 0 0 0; text-overflow: ellipsis; white-space: nowrap; overflow: hidden;">{safe_title}</h5>
                </div>
            </div>
            <div style="padding: 16px; display: flex; flex-direction: column; gap: 10px;">
                <div style="display: flex; justify-content: space-between; font-size: 11px; align-items: center;">
                    <span style="color: #6f6257;">Narrator:</span>
                    <span style="font-weight: 600; color: #944a00;">🌟 {bk['voice_name']}</span>
                </div>
                <div class="progress-bar-bg">
                    <div class="progress-bar-fill" style="width: {bk['percentage']}%"></div>
                </div>
                <div style="text-align: center; padding: 6px 0; font-size: 12px; font-weight: 700; color: #944a00;">
                    ▶️ Tap to Play
                </div>
            </div>
        </div>
        """
    html_out += "</div>"
    return html_out

def load_paragraphs(story_path: str) -> list:
    try:
        with open(story_path, encoding="utf-8") as f:
            raw = f.read()
        paras = [p.strip() for p in raw.split("\n\n") if p.strip()]
        return paras
    except Exception:
        return []

def render_story_text(paragraphs: list, current_idx: int) -> str:
    if not paragraphs:
        return ""
    result = """<div style="max-height: 420px; overflow-y: auto; padding: 4px 2px; margin-top: 12px;">"""
    for i, para in enumerate(paragraphs):
        safe_para = html.escape(para)
        if i == current_idx:
            result += f"""<p style="font-family: 'Playfair Display', Georgia, serif; font-size: 13px; line-height: 1.8; color: #FAF7F2; background: rgba(245,132,31,0.18); border-left: 3px solid #f5841f; padding: 8px 12px; border-radius: 6px; margin: 6px 0;">{safe_para}</p>"""
        else:
            result += f"""<p style="font-family: 'Playfair Display', Georgia, serif; font-size: 13px; line-height: 1.8; color: #94a3b8; padding: 4px 12px; margin: 4px 0;">{safe_para}</p>"""
    result += "</div>"
    return result

def render_cloned_voices_html(voices_list):
    markup = """<div class="book-shelf-grid">"""
    for v in voices_list:
        status_color = "#16a34a" if v["status"] == "ready" else "#d97706"
        status_bg = "#f0fdf4" if v["status"] == "ready" else "#fef3c7"
        safe_name = html.escape(v['name'])
        safe_desc = html.escape(v['description'])
        voice_id = html.escape(v.get('profile_id', v['id']))

        onclick = f"""onclick="
            const sel = document.querySelector('#voice_selector textarea, #voice_selector input');
            if (sel) {{
                sel.value = '{voice_id}';
                sel.dispatchEvent(new Event('input', {{bubbles: true}}));
                sel.dispatchEvent(new Event('change', {{bubbles: true}}));
            }}
            document.querySelectorAll('.voice-card-selected').forEach(c => c.classList.remove('voice-card-selected'));
            this.classList.add('voice-card-selected');
        " """

        markup += f"""
        <div class="shelf-card" style="align-items: center; cursor: pointer;" {onclick}>
            <div style="width: 48px; height: 48px; border-radius: 50%; background: #ede8e3; border: 1px solid #ddc1b0; font-size: 24px; display: flex; align-items: center; justify-content: center; shrink-0: 0;">
                {v['avatar_url']}
            </div>
            <div style="min-width: 0; flex: 1;">
                <div style="display: flex; justify-content: space-between; align-items: center; gap: 6px;">
                    <h5 class="serif-header" style="font-size: 14.5px; margin: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;">{safe_name}</h5>
                    <span style="font-size: 9px; font-weight: 700; text-transform: uppercase; padding: 2px 6px; border-radius: 4px; color: {status_color}; background: {status_bg};">
                        {v['status']}
                    </span>
                </div>
                <p style="font-size: 11.5px; color: #6f6257; margin: 4px 0 0 0; clamp: 2; overflow: hidden; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical;">
                    {safe_desc}
                </p>
                <div style="border-top: 1px solid rgba(148,74,0,0.08); padding-top: 6px; margin-top: 6px; display: flex; justify-content: space-between; font-size: 10px; color: #6f6257;">
                    <span>Gender: {v['gender']}</span>
                    <span>Created: {v['created_date']}</span>
                </div>
            </div>
        </div>
        """
    markup += "</div>"
    return markup


# Load default voice profile from Voice_Profile/ (if any saved from previous sessions)
_default_profile_id = load_default_profile()
_saved_profiles = list_saved_profiles()
if _default_profile_id:
    _default_voice_name = next(
        (p["voice_name"] for p in _saved_profiles if p["profile_id"] == _default_profile_id),
        "Cloned Voice"
    )
    print(f"[MomsVoice] Default voice profile loaded: {_default_profile_id} ({_default_voice_name})")
else:
    _default_voice_name = None
    print("[MomsVoice] No saved voice profile — using stock voice as default.")

# Preload models at startup for fast response
print("[MomsVoice] Preloading Qwen3-TTS 1.7B Base model (cloning + stock voice)...")
from voice_clone import get_qwen_tts, _ensure_stock_voice_profile
get_qwen_tts()
print("[MomsVoice] TTS model ready.")

# Pre-create stock voice profile so Play works immediately
print("[MomsVoice] Creating stock voice profile (vivian)...")
_ensure_stock_voice_profile()
print("[MomsVoice] Stock voice profile ready.")

# Load LFM Q&A model asynchronously — users typically start with Play tab,
# so LFM can load in the background while they browse stories.
import threading

def _load_lfm_background():
    from inference_lfm import get_lfm_model, warmup_lfm
    print("[MomsVoice] (background) Loading LFM2.5-Audio-1.5B Q&A model...")
    get_lfm_model()
    print("[MomsVoice] (background) LFM loaded. Running warmup generation...")
    warmup_lfm()
    print("[MomsVoice] (background) LFM Q&A model ready (compiled + warmed up).")

_lfm_thread = threading.Thread(target=_load_lfm_background, daemon=True)
_lfm_thread.start()
print("[MomsVoice] LFM loading in background thread. App starting now.")


# Gradio Application Core setup
with gr.Blocks(title="MomsVoice", css=css_code) as demo:

    books_state = gr.State(mock_books)
    voices_state = gr.State(mock_voices)
    paragraphs_state = gr.State([])
    tts_chunks_state = gr.State([])
    voice_profile_state = gr.State(_default_profile_id)

    gr.HTML("""
    <div style="display: flex; align-items: center; justify-content: space-between; padding: 16px 0; border-bottom: 1px solid #ebdccb; margin-bottom: 24px; flex-wrap: wrap; gap: 16px;">
        <div style="display: flex; align-items: center; gap: 12px;">
            <div style="width: 42px; height: 42px; background-color: #944a00; border-radius: 12px; display: flex; align-items: center; justify-content: center; color: white; font-weight: bold; font-size: 20px;">
                💿
            </div>
            <div>
                <h1 class="serif-header" style="font-size: 22px; margin: 0; line-height: 1;">VoiceBook</h1>
                <span style="font-size: 10px; color: #f5841f; font-weight: 700; text-transform: uppercase; letter-spacing: 1.5px;">AI Bedtime Story Narrator</span>
            </div>
        </div>
        <div style="display: flex; align-items: center; gap: 6px; font-size: 11.5px; color: #6f6257; font-family: monospace;">
            <span>Hugging Face Space Node:</span>
            <span style="color: #16a34a; font-weight: 700;">● Active</span>
        </div>
    </div>
    """)

    with gr.Tabs() as main_tabs:

        # TAB 1: Explore Dashboard
        with gr.TabItem("🏛️ Explore Space") as explore_tab:
            dashboard_container = gr.HTML(value=generate_dashboard_html(mock_books))
            gr.HTML("""<div style="margin-top: 24px; text-align: center;"><span style="font-size: 12px; color:#6f6257;">🎧 Head over to <b>My Library</b> and tap any book to start listening!</span></div>""")

        # TAB 2: Library + Player (통합)
        with gr.TabItem("📚 My Library") as library_tab:
            with gr.Row():
                # Left: book grid
                with gr.Column(scale=3):
                    with gr.Row():
                        with gr.Column(scale=3):
                            search_input = gr.Textbox(placeholder="Search by title, author, or voice...", label="Filter", show_label=False)
                        with gr.Column(scale=1):
                            category_filter = gr.Radio(["All", "In Progress", "Completed"], value="All", label="Progress", show_label=False)

                    shelf_grid = gr.HTML(value=generate_library_html(mock_books))

                    # Hidden radio — book cards click this via JS onclick
                    book_titles_list = [b["title"] for b in mock_books]
                    book_selector = gr.Radio(
                        choices=book_titles_list,
                        value=None,
                        label="",
                        show_label=False,
                        elem_classes="library-book-selector",
                        visible=False,
                    )

                # Right: player panel
                with gr.Column(scale=2, elem_classes="dark-card-container"):
                    gr.HTML("""
                        <div style="display: flex; justify-content: space-between; align-items: center; border-bottom: 1px dashed rgba(255,255,255,0.15); padding-bottom: 12px; margin-bottom: 16px;">
                            <span style="font-size: 10px; text-transform: uppercase; letter-spacing: 2px; color: #f5841f; font-weight: 700;">Now Playing</span>
                            <span style="background: rgba(22, 163, 74, 0.2); padding: 2px 6px; border-radius: 6px; font-size: 9px; font-family: monospace; color: #4ade80;">SYNCHRONIZED PITCH</span>
                        </div>
                    """)

                    player_title_info = gr.HTML("""
                        <div style="text-align: center; margin-bottom: 24px; margin-top: 16px; padding: 32px 0;">
                            <span style="font-size: 48px;">📖</span>
                            <h3 style="font-family: 'Playfair Display', Georgia, serif; font-size: 18px; margin: 12px 0 4px; color:#FAF7F2;">Select a story</h3>
                            <p style="font-size: 12px; color: #94a3b8; font-style: italic;">Tap any book on the left to begin</p>
                        </div>
                    """)

                    player_audio_control = gr.Audio(
                        visible=False, interactive=False,
                        label="Audio Stream",
                        type="numpy",
                        streaming=True,
                        autoplay=True,
                    )

                    player_status_bar = gr.HTML("""
                        <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                            <span style="width: 8px; height: 8px; border-radius: 50%; background: #94a3b8; display: inline-block;"></span>
                            <span style="font-size: 11px; color: #94a3b8; font-family: monospace;">SELECT A STORY</span>
                        </div>
                    """)

                    with gr.Row():
                        play_btn   = gr.Button("▶️ Play",          variant="primary",   scale=1, visible=False)
                        pause_btn  = gr.Button("⏸ Pause",          variant="secondary",  scale=1, visible=False)
                        resume_btn = gr.Button("↩️ Resume Story",   variant="secondary",  scale=2, visible=False)

                    chunk_status = gr.HTML("""
                        <div style="margin-top: 8px; font-size: 10px; color: #64748b; font-family: monospace; text-align: center;">
                            Chunk 0 / 0
                        </div>
                    """)

                    story_finished_panel = gr.HTML("""
                        <div style="margin-top: 12px; padding: 16px; background: rgba(245,132,31,0.1); border: 1px solid rgba(245,132,31,0.3); border-radius: 14px; text-align: center;">
                            <span style="font-size: 28px;">🎉</span>
                            <h4 style="font-family: 'Playfair Display', Georgia, serif; color: #ffd3a6; margin: 8px 0 4px;">Story Complete!</h4>
                            <p style="font-size: 12px; color: #94a3b8; margin-bottom: 12px;">Tap another book to start a new story.</p>
                        </div>
                    """, visible=False)

                    # Story text display + slider
                    story_text_display = gr.HTML(visible=False)
                    timeline_slider = gr.Slider(minimum=0, maximum=100, step=1, value=0, label="📍 Story position (paragraph)", visible=False)

                    # Q&A Panel — always visible
                    qa_panel = gr.HTML("""
                        <div style="margin-top: 20px; border-top: 1px solid rgba(255,255,255,0.1); padding-top: 16px;">
                            <h4 style="font-family: 'Playfair Display', Georgia, serif; font-size: 14px; margin-bottom: 12px; color: #FAF7F2;">❓ Ask About the Story</h4>
                        </div>
                    """)

                    with gr.Group() as qa_input_group:
                        question_audio = gr.Audio(
                            sources=["microphone"], type="filepath",
                            label="🎤 Ask your question — answer generates when you stop recording",
                            show_label=True, streaming=False,
                            format="wav",
                            elem_id="qa_audio_input",
                        )
                        question_text = gr.Textbox(
                            placeholder="…or type a question here",
                            label="Question (text fallback)",
                        )
                        submit_question_btn = gr.Button("🔍 Get Answer", variant="primary", elem_id="qa_submit_btn")

                    answer_display = gr.HTML()
                    answer_audio = gr.Audio(label="Answer Audio", interactive=False, autoplay=True, show_download_button=False)

                    with gr.Row():
                        ask_btn = gr.Button("❓ Ask a Question", variant="primary", scale=2, visible=False)

        # TAB 3: Clone Voice Studio
        with gr.TabItem("🎙️ Clone Voice Studio") as clone_tab:
            with gr.Row():
                with gr.Column(scale=1, elem_classes="card-container"):
                    gr.HTML("""
                        <h3 class="serif-header" style="font-size: 18px; margin-bottom: 4px; display: flex; align-items: center; gap: 8px;">🧙 Voice Details Form</h3>
                        <p style="font-size: 12px; color: #6f6257; margin-bottom: 20px;">Provide a comforting nickname and details below to prepare vocal weights matching.</p>
                    """)

                    new_voice_name = gr.Textbox(placeholder="Enter a descriptive nickname (e.g., Grandma Judy, Dad)...", label="Voice Nickname")
                    new_voice_gender = gr.Radio(["Female", "Male"], value="Female", label="Voice Gender Avatar")

                    gr.HTML("""
                        <div style="margin: 16px 0; padding: 12px; background: white; border-radius: 12px; border: 1px solid #ebdccb; font-size: 12px;">
                            <strong style="color: #6f6257; text-transform: uppercase; font-size: 10px; display: block; margin-bottom: 4px;">Story Script to read aloud:</strong>
                            <p style="font-family: Georgia, serif; font-style: italic; color: #1c1c19; margin: 0; line-height: 1.4;">
                                "Deep within the ancient forest, the giant oak tree stood. Its roots whispered stories of forgotten eras. 'Close your eyes,' the wind hummed softly, 'for our beautiful journey begins tonight.'"
                            </p>
                        </div>
                    """)

                    mic_recorder = gr.Audio(sources=["microphone"], type="filepath", label="Record speaking story prompt (Min 10 seconds sample)")
                    extract_btn = gr.Button("🪄 Analyze & Synthesize Customized Vocal Profile", variant="primary")

                with gr.Column(scale=1, elem_classes="card-container"):
                    gr.HTML("""
                        <h3 class="serif-header" style="font-size: 18px; margin-bottom: 4px;">Status Pipeline Visualizer</h3>
                        <p style="font-size: 12px; color: #6f6257; margin-bottom: 16px;">Track extraction, de-noising, and pitch tuning.</p>
                    """)

                    cloning_progress_msg = gr.HTML("""
                        <div style="text-align: center; padding: 32px 0;">
                            <span style="font-size: 42px;">🎙️</span>
                            <p style="margin-top: 12px; font-size: 14px; color: #6f6257;">Fill parameters on the left and read the story script aloud to begin extraction.</p>
                        </div>
                    """)

                    voice_cloning_success_panel = gr.HTML(visible=False)
                    voice_sample_preview_widget = gr.Audio(value=str(_preview_chime_path), visible=False, label="Pre-listening synthesized vocal pitch weights match preview", interactive=False)
                    add_to_library_btn = gr.Button("✨ Synced successfully! Bind Companion Voice to Inventory", visible=False)

            gr.HTML("""
                <div style="margin-top: 32px; border-top: 1px solid #ebdccb; padding-top: 24px;">
                    <h4 class="serif-header" style="font-size: 18px; margin-bottom: 16px;">Currently Available Voices</h4>
                    <p style="font-size: 11px; color: #6f6257; margin-bottom: 12px;">Click a voice card to select it as the narrator.</p>
                </div>
            """)
            cloned_voices_list_grid = gr.HTML(value=render_cloned_voices_html(mock_voices))
            voice_selector = gr.Textbox(visible=False, elem_id="voice_selector")

        # TAB 4: Profile
        with gr.TabItem("⚙️ Profile") as profile_tab:
            with gr.Row():
                with gr.Column(scale=1, elem_classes="card-container"):
                    gr.HTML("""
                        <div style="text-align: center; margin-bottom: 24px;">
                            <div style="width: 72px; height: 72px; border-radius: 50%; background: #944a00; color: white; font-size: 36px; display: flex; align-items: center; justify-content: center; margin: 0 auto 12px auto;">
                                👩‍💻
                            </div>
                            <h3 class="serif-header" style="font-size: 18px; margin: 0;">Your Profile</h3>
                            <p style="font-size: 11.5px; color: #6f6257; margin-top: 2px;">ReadBookMom — Hugging Face Hackathon 2026</p>
                        </div>
                    """)

                    gr.HTML("""
                        <div style="display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 8px; text-align: center;">
                            <div style="background: white; border: 1px solid #ebdccb; border-radius: 12px; padding: 10px;">
                                <span style="font-size: 18px; display: block;">📚</span>
                                <strong style="font-size: 15px; display: block; color: #1c1c19;">10</strong>
                                <span style="font-size: 9px; text-transform: uppercase; color: #6f6257;">Stories</span>
                            </div>
                            <div style="background: white; border: 1px solid #ebdccb; border-radius: 12px; padding: 10px;">
                                <span style="font-size: 18px; display: block;">🧠</span>
                                <strong style="font-size: 15px; display: block; color: #1c1c19;">2</strong>
                                <span style="font-size: 9px; text-transform: uppercase; color: #6f6257;">Models</span>
                            </div>
                            <div style="background: white; border: 1px solid #ebdccb; border-radius: 12px; padding: 10px;">
                                <span style="font-size: 18px; display: block;">🎙️</span>
                                <strong style="font-size: 15px; display: block; color: #1c1c19;">Base 1.7B</strong>
                                <span style="font-size: 9px; text-transform: uppercase; color: #6f6257;">TTS Engine</span>
                            </div>
                        </div>
                    """)

                with gr.Column(scale=1, elem_classes="card-container"):
                    gr.HTML("""
                        <h3 class="serif-header" style="font-size: 18px; margin-bottom: 4px;">Model Pipeline</h3>
                        <p style="font-size: 12px; color: #6f6257; margin-bottom: 16px;">Active AI models powering the app.</p>
                    """)

                    gr.HTML("""
                        <div style="padding: 12px; background: white; border-radius: 12px; border: 1px solid #ebdccb;">
                            <div style="font-size: 11.5px; color: #1c1c19; line-height: 2;">
                                🎙️ <strong>TTS + Cloning:</strong> Qwen3-TTS-1.7B-Base (single model)<br>
                                🗣️ <strong>Stock Voice:</strong> Vivian (via reference audio)<br>
                                🧠 <strong>Q&A (end-to-end):</strong> LFM2.5-Audio-1.5B (LiquidAI)
                            </div>
                        </div>
                    """)

    # REACTIVE LOGIC

    # 1. Search / filter shelf
    def filter_books_shelf(query, category, current_books):
        return generate_library_html(current_books, query=query, category_filt=category)

    search_input.change(filter_books_shelf, inputs=[search_input, category_filter, books_state], outputs=shelf_grid)
    category_filter.change(filter_books_shelf, inputs=[search_input, category_filter, books_state], outputs=shelf_grid)

    # 2. Book card click → load into player
    def handle_book_select(title_chosen, current_inventory, profile_id):
        if not title_chosen:
            return [gr.update()] * 12
        selected = next((b for b in current_inventory if b["title"] == title_chosen), current_inventory[0])

        # Show cloned voice name if profile exists
        from voice_clone import has_profile, list_saved_profiles as _list_profiles
        if profile_id and has_profile(profile_id):
            saved = _list_profiles()
            voice_label = next(
                (p["voice_name"] for p in saved if p["profile_id"] == profile_id),
                "Cloned Voice"
            )
            narrator_label = f"🎙️ {voice_label}"
            narrator_color = "#4ade80"
        else:
            narrator_label = f"🔊 {selected['voice_name']} (stock)"
            narrator_color = "#ffd3a6"

        safe_title = html.escape(selected['title'])
        safe_author = html.escape(selected['author'])
        player_html = f"""
        <div style="text-align: center; margin-bottom: 16px; margin-top: 8px;">
            <img src="{selected['cover_url']}" style="width: 110px; height: 155px; object-fit: cover; border-radius: 12px; box-shadow: 0 4px 16px rgba(0,0,0,0.4); margin-bottom: 12px;" />
            <h3 style="font-family: 'Playfair Display', Georgia, serif; font-size: 20px; margin:0; color:#FAF7F2;">{safe_title}</h3>
            <p style="font-size: 12px; color: #94a3b8; font-style: italic; margin-top:2px;">by {safe_author}</p>
            <span style="display: inline-block; background: rgba(245, 132, 31, 0.15); color: {narrator_color}; font-size: 10.5px; font-weight: 700; padding: 3px 8px; border-radius: 999px; margin-top: 6px;">Active Narrator: {narrator_label}</span>
        </div>
        """
        paras = load_paragraphs(selected["story_path"])
        total = max(len(paras) - 1, 0)
        tts_chunks = split_into_chunks("\n\n".join(paras))
        
        # Pre-generate only the first few chunks in background for fast start.
        cancel_pregeneration()
        pregenerate_story_audio(tts_chunks, voice_profile_id=profile_id)

        pregen = get_pregeneration_status(tts_chunks, voice_profile_id=profile_id)
        warmed = int(pregen["cached"])
        total_chunks = int(pregen["total"])
        target_chunks = int(pregen.get("target", min(total_chunks, 3)))
        errors = int(pregen.get("errors", 0))
        if pregen["complete"]:
            chunk_text = f"{warmed} / {total_chunks} chunks cached — ready"
            chunk_color = "#4ade80"
            status_label = "READY"
            status_color = "#94a3b8"
        elif warmed >= target_chunks and errors == 0:
            chunk_text = f"First {target_chunks} chunks cached — tap Play"
            chunk_color = "#4ade80"
            status_label = "READY — FIRST CHUNKS CACHED"
            status_color = "#4ade80"
        elif errors:
            chunk_text = f"Warmup hit {errors} error(s); Play will generate on demand"
            chunk_color = "#ef4444"
            status_label = "READY — ON-DEMAND AUDIO"
            status_color = "#f59e0b"
        else:
            chunk_text = f"Warming first {target_chunks} chunks: {warmed} / {target_chunks} cached — tap Play anytime"
            chunk_color = "#f59e0b"
            status_label = "WARMING AUDIO"
            status_color = "#f59e0b"
        chunk_html = f"""<div style="margin-top: 8px; font-size: 10px; color: {chunk_color}; font-family: monospace; text-align: center;">{chunk_text}</div>"""
        status_html = f"""
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: {status_color}; display: inline-block;"></span>
                <span style="font-size: 11px; color: {status_color}; font-family: monospace;">{status_label}</span>
            </div>
        """
        story_html = render_story_text(paras, 0)
        return (
            player_html,
            gr.Audio(visible=True),
            status_html,
            chunk_html,
            gr.Button(visible=True),   # play_btn
            gr.Button(visible=False),  # pause_btn
            gr.Button(visible=False),  # ask_btn
            gr.HTML(visible=False),    # story_finished_panel
            paras,                     # paragraphs_state
            tts_chunks,                # tts_chunks_state
            gr.HTML(value=story_html, visible=True),   # story_text_display
            gr.Slider(minimum=0, maximum=total, step=1, value=0, visible=True),  # timeline_slider
        )

    book_selector.change(
        handle_book_select,
        inputs=[book_selector, books_state, voice_profile_state],
        outputs=[player_title_info, player_audio_control, player_status_bar, chunk_status,
                 play_btn, pause_btn, ask_btn, story_finished_panel,
                 paragraphs_state, tts_chunks_state, story_text_display, timeline_slider]
    )

    # 3. Extract vocal weights trigger
    def animate_cloning_pipeline(v_name, v_gender, recorder_data, progress=gr.Progress()):
        if not v_name.strip():
            return (
                """<div style="padding: 12px; background: #fef2f2; border: 1px solid #fecaca; color: #991b1b; border-radius: 12px; font-size: 12px; font-weight: 600;">
                    Please provide a comforting nickname for your cloning candidate.
                   </div>""",
                gr.HTML(visible=False),
                gr.Audio(visible=False),
                gr.Button(visible=False),
                None,
            )
        if recorder_data is None:
            return (
                """<div style="padding: 12px; background: #fef2f2; border: 1px solid #fecaca; color: #991b1b; border-radius: 12px; font-size: 12px; font-weight: 600;">
                    Microphone recording sample missing. Speak some script lines!
                   </div>""",
                gr.HTML(visible=False),
                gr.Audio(visible=False),
                gr.Button(visible=False),
                None,
            )

        from voice_clone import create_voice_profile, synthesize_cloned_preview
        import soundfile as sf

        progress(0.1, desc="Extracting speaker embedding from recording...")
        try:
            profile_id = create_voice_profile(recorder_data, voice_name=v_name.strip())
        except Exception as e:
            import logging, traceback
            logging.getLogger(__name__).exception("Voice cloning failed")
            return (
                f"""<div style="padding: 12px; background: #fef2f2; border: 1px solid #fecaca; color: #991b1b; border-radius: 12px; font-size: 12px; font-weight: 600;">
                    Voice cloning failed: {html.escape(str(e))}
                   </div>""",
                gr.HTML(visible=False),
                gr.Audio(visible=False),
                gr.Button(visible=False),
                None,
            )

        progress(0.7, desc="Generating voice preview...")
        try:
            preview_wav, preview_sr = synthesize_cloned_preview(profile_id)
            preview_path = SAMPLE_SOUNDS_DIR / f"clone_preview_{profile_id}.wav"
            sf.write(str(preview_path), preview_wav, preview_sr)
        except Exception as e:
            import logging
            logging.getLogger(__name__).exception("Preview synthesis failed")
            preview_path = None

        progress(1.0, desc="Voice cloned successfully!")

        safe_name = html.escape(v_name)
        avatar = "👩" if v_gender == "Female" else "👨"

        cloned_card_html = f"""
        <div style="background: white; border: 1px solid #ebdccb; padding: 24px; border-radius: 16px; margin: 16px 0;">
            <div style="display: flex; gap: 16px; align-items: center; margin-bottom: 12px;">
                <div style="width: 48px; height: 48px; border-radius: 50%; background: #944a00; color: white; display: flex; align-items: center; justify-content: center; font-size: 24px;">
                    {avatar}
                </div>
                <div>
                    <h4 class="serif-header" style="font-size: 16px; margin: 0;">{safe_name} <span style="font-size: 9px; background: #f0fdf4; color: #16a34a; padding: 2px 6px; border-radius: 4px; font-weight:700;">Cloned successfully</span></h4>
                    <p style="font-size: 11px; color:#6f6257; margin-top:2px;">Synthesized today using Qwen3-TTS voice cloning</p>
                </div>
            </div>
            <div style="background:#FAF7F2; border-left: 3px solid #f5841f; padding: 10px; font-family: Georgia, serif; font-style: italic; font-size: 12px; color: #1c1c19;">
                Voice profile ready. Select a story and tap Play to hear narration in this voice.
            </div>
        </div>
        """

        return (
            gr.HTML(visible=False),
            gr.HTML(value=cloned_card_html, visible=True),
            gr.Audio(value=str(preview_path) if preview_path else None, visible=preview_path is not None),
            gr.Button(visible=True),
            profile_id,
        )

    extract_btn.click(
        animate_cloning_pipeline,
        inputs=[new_voice_name, new_voice_gender, mic_recorder],
        outputs=[cloning_progress_msg, voice_cloning_success_panel, voice_sample_preview_widget, add_to_library_btn, voice_profile_state]
    )

    # 4. Add cloned voice to inventory
    def save_new_cloned_voice(v_name, v_gender, list_voices, current_profile_id):
        avatar = "👩" if v_gender == "Female" else "👨"
        new_voice_item = {
            "id": f"v-{time.time()}",
            "name": v_name,
            "avatar_url": avatar,
            "description": f"Custom cloned {v_gender.lower()} companion voice. Highly optimized.",
            "gender": v_gender,
            "created_date": "2026-06-06",
            "status": "ready",
            "profile_id": current_profile_id,
        }
        updated = [new_voice_item] + list_voices
        return (
            updated,
            render_cloned_voices_html(updated),
            gr.HTML(visible=True, value="""<div style="text-align: center; padding: 32px 0;"><span style="font-size:42px;">🎙️</span><p style="margin-top:12px; font-size:14px; color:#6f6257;">Vocal profile saved successfully!</p></div>"""),
            gr.HTML(visible=False),
            gr.Audio(visible=False),
            gr.Button(visible=False),
            gr.Textbox(value="")
        )

    add_to_library_btn.click(
        save_new_cloned_voice,
        inputs=[new_voice_name, new_voice_gender, voices_state, voice_profile_state],
        outputs=[voices_state, cloned_voices_list_grid, cloning_progress_msg, voice_cloning_success_panel, voice_sample_preview_widget, add_to_library_btn, new_voice_name]
    )

    # Voice card selection — update voice_profile_state when a card is clicked
    def handle_voice_select(selected_id, voices):
        """Map selected voice ID to profile_id for TTS."""
        if not selected_id:
            return gr.update()
        # Check if it matches a saved profile ID directly
        from voice_clone import has_profile
        if has_profile(selected_id):
            return selected_id
        # Check if it matches a voice in the list with a profile_id
        for v in voices:
            if v.get('profile_id') == selected_id or v.get('id') == selected_id:
                pid = v.get('profile_id')
                if pid and has_profile(pid):
                    return pid
        # No valid profile — use stock voice (None)
        return None

    voice_selector.change(
        handle_voice_select,
        inputs=[voice_selector, voices_state],
        outputs=[voice_profile_state]
    )

    # 5. Play button — streams TTS audio chunk by chunk
    def stream_tts(tts_chunks, paras, profile_id):
        import logging as _log
        _log.getLogger(__name__).info("stream_tts called with profile_id=%s", profile_id)

        voice_mode = "🎙️ Cloned Voice" if profile_id else "🔊 Stock Voice"
        _status_playing = f"""
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: #4ade80; display: inline-block;"></span>
                <span style="font-size: 11px; color: #4ade80; font-family: monospace;">PLAYING — {voice_mode}</span>
            </div>
        """
        _status_done = """
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: #94a3b8; display: inline-block;"></span>
                <span style="font-size: 11px; color: #94a3b8; font-family: monospace;">DONE</span>
            </div>
        """

        n_paras = len(paras) if paras else 1

        if not tts_chunks:
            yield (gr.update(), _status_done,
                   "<div style='text-align:center;font-size:10px;color:#64748b;font-family:monospace;margin-top:8px;'>No content loaded</div>",
                   gr.Button(visible=True), gr.Button(visible=False), gr.Button(visible=False),
                   gr.Slider(value=0), render_story_text(paras, 0) if paras else "",
                   gr.HTML(visible=False), gr.Button(visible=False))
            return

        n = len(tts_chunks)
        yield (gr.update(), _status_playing,
               f"<div style='text-align:center;font-size:10px;color:#4ade80;font-family:monospace;margin-top:8px;'>▶ Paragraph 1 / {n_paras}</div>",
               gr.Button(visible=False), gr.Button(visible=True), gr.Button(visible=False),
               gr.Slider(value=0), render_story_text(paras, 0) if paras else "",
               gr.HTML(visible=False), gr.Button(visible=False))

        for sample_rate, wav, i, total, err in generate_audio_stream(tts_chunks, voice_profile_id=profile_id):
            para_idx = min(int(i * n_paras / total), n_paras - 1) if total > 0 else 0
            if err:
                yield (gr.update(), f"<div style='color:#ef4444;font-size:11px;'>Something went wrong. Try again.</div>", "",
                       gr.Button(visible=True), gr.Button(visible=False), gr.Button(visible=False),
                       gr.Slider(value=para_idx), gr.update(), gr.HTML(visible=False),
                       gr.Button(visible=False))
                return
            para_idx = min(int(i * n_paras / total), n_paras - 1) if total > 0 else 0
            is_last = (i + 1 >= total)
            para_status = f"<div style='text-align:center;font-size:10px;color:#4ade80;font-family:monospace;margin-top:8px;'>▶ Paragraph {para_idx + 1} / {n_paras}</div>"
            yield ((sample_rate, wav.astype(np.float32) if hasattr(wav, 'astype') else wav), _status_playing, para_status,
                   gr.Button(visible=False), gr.Button(visible=True), gr.Button(visible=True),
                   gr.Slider(value=para_idx), render_story_text(paras, para_idx),
                   gr.HTML(visible=is_last), gr.Button(visible=True))

        yield (gr.update(), _status_done, f"<div style='text-align:center;font-size:10px;color:#94a3b8;font-family:monospace;margin-top:8px;'>✅ Story complete</div>",
               gr.Button(visible=True), gr.Button(visible=False), gr.Button(visible=False),
               gr.Slider(value=max(n_paras - 1, 0)), render_story_text(paras, max(n_paras - 1, 0)),
               gr.HTML(visible=True), gr.Button(visible=True))

    play_event = play_btn.click(
        stream_tts,
        inputs=[tts_chunks_state, paragraphs_state, voice_profile_state],
        outputs=[player_audio_control, player_status_bar, chunk_status, play_btn, pause_btn, ask_btn,
                 timeline_slider, story_text_display, story_finished_panel, resume_btn]
    )

    # 6. Pause button — PAUSED state
    def enter_paused_state(slider_val, paras):
        total = len(paras) if paras else 1
        chunk_html = f"""<div style="margin-top: 8px; font-size: 10px; color: #f59e0b; font-family: monospace; text-align: center;">Paragraph {int(slider_val) + 1} / {total} — paused</div>"""
        status_html = """
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: #f59e0b; display: inline-block;"></span>
                <span style="font-size: 11px; color: #f59e0b; font-family: monospace;">PAUSED</span>
            </div>
        """
        return (
            status_html,
            chunk_html,
            gr.Button(visible=True),
            gr.Button(visible=False),
        )

    pause_btn.click(
        enter_paused_state,
        inputs=[timeline_slider, paragraphs_state],
        outputs=[player_status_bar, chunk_status, play_btn, pause_btn],
        cancels=[play_event]
    )

    # 7. Timeline slider → highlight current paragraph
    def update_story_highlight(slider_val, paras):
        idx = int(slider_val)
        total = len(paras)
        chunk_html = f"""<div style="margin-top: 8px; font-size: 10px; color: #64748b; font-family: monospace; text-align: center;">Paragraph {idx + 1} / {total}</div>"""
        return render_story_text(paras, idx), chunk_html

    timeline_slider.change(update_story_highlight, inputs=[timeline_slider, paragraphs_state], outputs=[story_text_display, chunk_status])

    # 8. Ask button — PAUSED-ASKING state
    def enter_asking_state():
        cancel_pregeneration()
        status_html = """
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: #f59e0b; display: inline-block; animation: pulse 1s infinite;"></span>
                <span style="font-size: 11px; color: #f59e0b; font-family: monospace;">PAUSED — ASKING</span>
            </div>
        """
        return (
            status_html,
            gr.Button(visible=False),  # play_btn
            gr.Button(visible=False),  # pause_btn
            gr.Button(visible=False),  # ask_btn
            gr.Button(visible=True),   # resume_btn
            gr.HTML(value=""),         # answer_display — clear previous answer
            gr.Audio(visible=False),   # answer_audio
        )

    ask_btn.click(
        enter_asking_state,
        inputs=[],
        outputs=[player_status_bar, play_btn, pause_btn, ask_btn, resume_btn, answer_display, answer_audio],
        cancels=[play_event],
    )

    # 9. Submit question — LFM2.5-Audio end-to-end (single model: audio-in → audio+text-out)
    _GENERATING_HTML = """
        <div style="margin-top: 12px; padding: 20px 16px; background: rgba(245,132,31,0.08); border: 1px solid rgba(245,132,31,0.25); border-radius: 14px; text-align: center;">
            <div style="font-size: 28px; margin-bottom: 10px;">🎧</div>
            <div style="font-size: 11px; color: #f5841f; font-family: monospace; font-weight: 700; letter-spacing: 1px;">GENERATING ANSWER...</div>
            <div style="margin-top: 10px; display: flex; justify-content: center; gap: 6px;">
                <span style="width: 7px; height: 7px; border-radius: 50%; background: #f5841f; display: inline-block; animation: pulse 1.2s ease-in-out infinite;"></span>
                <span style="width: 7px; height: 7px; border-radius: 50%; background: #f5841f; display: inline-block; animation: pulse 1.2s ease-in-out 0.3s infinite;"></span>
                <span style="width: 7px; height: 7px; border-radius: 50%; background: #f5841f; display: inline-block; animation: pulse 1.2s ease-in-out 0.6s infinite;"></span>
            </div>
        </div>
    """

    def _build_answer_outputs(result):
        if not result["ok"]:
            error_html = """
                <div style="padding: 10px; background: #fef2f2; border: 1px solid #fecaca; border-radius: 10px; font-size: 12px; color: #991b1b;">
                    Please type a question or record one with the microphone.
                </div>
            """
            return gr.HTML(value=error_html, visible=True), gr.Audio(visible=False)

        safe_answer = html.escape(str(result["answer_text"]))
        safe_question = html.escape(str(result["display_question"]))
        answer_html = f"""
            <div style="margin-top: 12px; padding: 16px; background: rgba(240,253,244,0.1); border: 1px solid rgba(187,247,208,0.3); border-radius: 14px;">
                <div style="font-size: 10px; font-weight: 700; text-transform: uppercase; color: #4ade80; margin-bottom: 6px;">Answer (LFM2.5-Audio)</div>
                <div style="font-family: 'Playfair Display', Georgia, serif; font-style: italic; color: #FAF7F2; font-size: 13px; line-height: 1.6;">
                    &ldquo;{safe_answer}&rdquo;
                </div>
                <div style="margin-top: 8px; font-size: 10px; color: #94a3b8;">
                    Q: <em>{safe_question}</em>
                </div>
            </div>
        """
        answer_audio_path_out = result["audio_path"]
        if answer_audio_path_out:
            return gr.HTML(value=answer_html, visible=True), gr.Audio(value=str(answer_audio_path_out), visible=True, autoplay=True)
        return gr.HTML(value=answer_html, visible=True), gr.Audio(visible=False)

    def handle_question_submit(question_txt, question_audio_path, paragraphs, slider_val, profile_id):
        q_txt = (question_txt or "").strip()
        has_audio = question_audio_path is not None and question_audio_path != ""

        yield gr.HTML(value=_GENERATING_HTML, visible=True), gr.Audio(visible=False)

        result = build_qa_response(
            question_text=q_txt,
            question_audio_path=question_audio_path if has_audio else None,
            paragraphs=paragraphs,
            output_dir=SAMPLE_SOUNDS_DIR,
            answer_fn=answer_question_audio,
            max_new_tokens=512,
        )
        yield _build_answer_outputs(result)

    submit_question_btn.click(
        handle_question_submit,
        inputs=[question_text, question_audio, paragraphs_state, timeline_slider, voice_profile_state],
        outputs=[answer_display, answer_audio]
    )

    # Auto-submit immediately when recording stops — show waiting UI then run inference
    def auto_submit_on_stop(audio_path, question_txt, paragraphs, slider_val, profile_id):
        if not audio_path:
            return
        if not claim_audio_submission(audio_path):
            return

        yield gr.HTML(value=_GENERATING_HTML, visible=True), gr.Audio(visible=False)

        result = build_qa_response(
            question_text=(question_txt or "").strip(),
            question_audio_path=audio_path,
            paragraphs=paragraphs,
            output_dir=SAMPLE_SOUNDS_DIR,
            answer_fn=answer_question_audio,
            max_new_tokens=512,
        )
        yield _build_answer_outputs(result)

    question_audio.stop_recording(
        auto_submit_on_stop,
        inputs=[question_audio, question_text, paragraphs_state, timeline_slider, voice_profile_state],
        outputs=[answer_display, answer_audio],
    )

    # 10. Resume button — dismiss Q&A panel, show Play to continue
    def enter_resume_state():
        status_html = """
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: #94a3b8; display: inline-block;"></span>
                <span style="font-size: 11px; color: #94a3b8; font-family: monospace;">READY — Tap Play to continue</span>
            </div>
        """
        return (
            status_html,
            gr.Button(visible=True),   # play_btn
            gr.Button(visible=False),  # pause_btn
            gr.Button(visible=True),   # ask_btn
            gr.Button(visible=False),  # resume_btn
            gr.Textbox(value=""),      # question_text — clear previous question
            None,                      # question_audio — clear previous recording
        )

    resume_btn.click(
        enter_resume_state,
        inputs=[],
        outputs=[player_status_bar, play_btn, pause_btn, ask_btn, resume_btn, question_text, question_audio]
    )

    # 11. Pause playback when switching to other tabs
    def pause_on_tab_switch():
        status_html = """
            <div style="margin-top: 12px; display: flex; align-items: center; gap: 10px; justify-content: center;">
                <span style="width: 8px; height: 8px; border-radius: 50%; background: #f59e0b; display: inline-block;"></span>
                <span style="font-size: 11px; color: #f59e0b; font-family: monospace;">PAUSED</span>
            </div>
        """
        return status_html, gr.Button(visible=True), gr.Button(visible=False)

    explore_tab.select(
        pause_on_tab_switch,
        inputs=[],
        outputs=[player_status_bar, play_btn, pause_btn],
        cancels=[play_event]
    )
    clone_tab.select(
        pause_on_tab_switch,
        inputs=[],
        outputs=[player_status_bar, play_btn, pause_btn],
        cancels=[play_event]
    )

if __name__ == "__main__":
    demo.queue(max_size=8).launch(allowed_paths=gradio_allowed_paths())