"""
Music Generation Studio - HuggingFace Spaces Deployment
Main application file for Gradio interface
"""
import os
import sys
import gradio as gr
import logging
from pathlib import Path
import shutil
import subprocess

# Run DiffRhythm2 source setup if needed
setup_script = Path(__file__).parent / "setup_diffrhythm2_src.sh"
if setup_script.exists():
    try:
        subprocess.run(["bash", str(setup_script)], check=True)
    except Exception as e:
        print(f"Warning: Failed to run setup script: {e}")

# Configure environment for HuggingFace Spaces (espeak-ng paths, etc.)
import hf_config

# Setup paths for HuggingFace Spaces
SPACE_DIR = Path(__file__).parent
sys.path.insert(0, str(SPACE_DIR / 'backend'))

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)

# Import services
try:
    from services.diffrhythm_service import DiffRhythmService
    from services.lyricmind_service import LyricMindService
    from services.timeline_service import TimelineService
    from services.export_service import ExportService
    from config.settings import Config
    from utils.prompt_analyzer import PromptAnalyzer
except ImportError as e:
    logger.error(f"Import error: {e}")
    raise

# Initialize configuration
config = Config()

# Create necessary directories
os.makedirs("outputs", exist_ok=True)
os.makedirs("outputs/music", exist_ok=True)
os.makedirs("outputs/mixed", exist_ok=True)
os.makedirs("models", exist_ok=True)
os.makedirs("logs", exist_ok=True)

# Initialize services
timeline_service = TimelineService()
export_service = ExportService()

# Lazy-load AI services (heavy models)
diffrhythm_service = None
lyricmind_service = None

def get_diffrhythm_service():
    """Lazy load DiffRhythm service"""
    global diffrhythm_service
    if diffrhythm_service is None:
        logger.info("Loading DiffRhythm2 model...")
        diffrhythm_service = DiffRhythmService(model_path=config.DIFFRHYTHM_MODEL_PATH)
        logger.info("DiffRhythm2 model loaded")
    return diffrhythm_service

def get_lyricmind_service():
    """Lazy load LyricMind service"""
    global lyricmind_service
    if lyricmind_service is None:
        logger.info("Loading LyricMind model...")
        lyricmind_service = LyricMindService(model_path=config.LYRICMIND_MODEL_PATH)
        logger.info("LyricMind model loaded")
    return lyricmind_service

def generate_lyrics(prompt: str, duration: int, progress=gr.Progress()):
    """Generate lyrics from prompt using analysis"""
    try:
        if not prompt or not prompt.strip():
            return "❌ Please enter a prompt"
        
        progress(0, desc="🔍 Analyzing prompt...")
        logger.info(f"Generating lyrics for: {prompt}")
        
        # Analyze prompt
        analysis = PromptAnalyzer.analyze(prompt)
        genre = analysis.get('genres', ['general'])[0] if analysis.get('genres') else 'general'
        mood = analysis.get('mood', 'unknown')
        
        logger.info(f"Analysis - Genre: {genre}, Mood: {mood}")
        
        progress(0.3, desc=f"✍️ Generating {genre} lyrics...")
        
        service = get_lyricmind_service()
        lyrics = service.generate(
            prompt=prompt,
            duration=duration,
            prompt_analysis=analysis
        )
        
        progress(1.0, desc="✅ Lyrics generated!")
        return lyrics
        
    except Exception as e:
        logger.error(f"Error generating lyrics: {e}", exc_info=True)
        return f"❌ Error: {str(e)}"

def generate_music(prompt: str, lyrics: str, lyrics_mode: str, duration: int, position: str, progress=gr.Progress()):
    """Generate music clip and add to timeline"""
    try:
        if not prompt or not prompt.strip():
            return "❌ Please enter a music prompt", get_timeline_display(), None
        
        # Estimate time (CPU on HF Spaces)
        est_time = int(duration * 4)  # Conservative estimate for CPU
        
        progress(0, desc=f"🔍 Analyzing prompt... (Est. {est_time}s)")
        logger.info(f"Generating music: {prompt}, mode={lyrics_mode}, duration={duration}s")
        
        # Analyze prompt
        analysis = PromptAnalyzer.analyze(prompt)
        genre = analysis.get('genres', ['general'])[0] if analysis.get('genres') else 'general'
        bpm = analysis.get('bpm', 120)
        mood = analysis.get('mood', 'neutral')
        
        logger.info(f"Analysis - Genre: {genre}, BPM: {bpm}, Mood: {mood}")
        
        # Determine lyrics based on mode
        lyrics_to_use = None
        
        if lyrics_mode == "Instrumental":
            logger.info("Generating instrumental (no vocals)")
            progress(0.1, desc=f"🎹 Preparing instrumental generation... ({est_time}s)")
            
        elif lyrics_mode == "User Lyrics":
            if not lyrics or not lyrics.strip():
                return "❌ Please enter lyrics or switch mode", get_timeline_display(), None
            lyrics_to_use = lyrics.strip()
            logger.info("Using user-provided lyrics")
            progress(0.1, desc=f"🎤 Preparing vocal generation... ({est_time}s)")
            
        elif lyrics_mode == "Auto Lyrics":
            if lyrics and lyrics.strip():
                lyrics_to_use = lyrics.strip()
                logger.info("Using existing lyrics from textbox")
                progress(0.1, desc=f"🎤 Using provided lyrics... ({est_time}s)")
            else:
                progress(0.1, desc="✍️ Generating lyrics...")
                logger.info("Auto-generating lyrics...")
                lyric_service = get_lyricmind_service()
                lyrics_to_use = lyric_service.generate(
                    prompt=prompt,
                    duration=duration,
                    prompt_analysis=analysis
                )
                logger.info(f"Generated {len(lyrics_to_use)} characters of lyrics")
                progress(0.25, desc=f"🎵 Lyrics ready, generating music... ({est_time}s)")
        
        # Generate music
        progress(0.3, desc=f"🎼 Generating {genre} at {bpm} BPM... ({est_time}s)")
        service = get_diffrhythm_service()
        
        final_path = service.generate(
            prompt=prompt,
            duration=duration,
            lyrics=lyrics_to_use
        )
        
        # Add to timeline
        progress(0.9, desc="📊 Adding to timeline...")
        clip_id = os.path.basename(final_path).split('.')[0]
        
        from models.schemas import ClipPosition
        clip_info = timeline_service.add_clip(
            clip_id=clip_id,
            file_path=final_path,
            duration=float(duration),
            position=ClipPosition(position)
        )
        
        logger.info(f"Music added to timeline at position {clip_info['timeline_position']}")
        
        # Build status message
        progress(1.0, desc="✅ Complete!")
        status_msg = f"✅ Music generated successfully!\n"
        status_msg += f"🎸 Genre: {genre} | 🥁 BPM: {bpm} | 🎭 Mood: {mood}\n"
        status_msg += f"🎤 Mode: {lyrics_mode} | 📍 Position: {position}\n"
        
        if lyrics_mode == "Auto Lyrics" and lyrics_to_use and not lyrics:
            status_msg += "✍️ (Lyrics auto-generated)"
        
        return status_msg, get_timeline_display(), final_path
        
    except Exception as e:
        logger.error(f"Error generating music: {e}", exc_info=True)
        return f"❌ Error: {str(e)}", get_timeline_display(), None

def get_timeline_display():
    """Get timeline clips as formatted text"""
    clips = timeline_service.get_all_clips()
    
    if not clips:
        return "📭 Timeline is empty. Generate clips to get started!"
    
    total_duration = timeline_service.get_total_duration()
    
    display = f"**📊 Timeline ({len(clips)} clips, {format_duration(total_duration)} total)**\n\n"
    
    for i, clip in enumerate(clips, 1):
        display += f"**{i}.** `{clip['clip_id'][:12]}...` | "
        display += f"⏱️ {format_duration(clip['duration'])} | "
        display += f"▶️ {format_duration(clip['start_time'])}\n"
    
    return display

def remove_clip(clip_number: int):
    """Remove a clip from timeline"""
    try:
        clips = timeline_service.get_all_clips()
        
        if not clips:
            return "📭 Timeline is empty", get_timeline_display()
        
        if clip_number < 1 or clip_number > len(clips):
            return f"❌ Invalid clip number. Choose 1-{len(clips)}", get_timeline_display()
        
        clip_id = clips[clip_number - 1]['clip_id']
        timeline_service.remove_clip(clip_id)
        
        return f"✅ Clip {clip_number} removed", get_timeline_display()
        
    except Exception as e:
        logger.error(f"Error removing clip: {e}", exc_info=True)
        return f"❌ Error: {str(e)}", get_timeline_display()

def clear_timeline():
    """Clear all clips from timeline"""
    try:
        timeline_service.clear()
        return "✅ Timeline cleared", get_timeline_display()
    except Exception as e:
        logger.error(f"Error clearing timeline: {e}", exc_info=True)
        return f"❌ Error: {str(e)}", get_timeline_display()

def export_timeline(filename: str, export_format: str, progress=gr.Progress()):
    """Export timeline to audio file"""
    try:
        clips = timeline_service.get_all_clips()
        
        if not clips:
            return "❌ No clips to export", None
        
        if not filename or not filename.strip():
            filename = "output"
        
        progress(0, desc="🔄 Merging clips...")
        logger.info(f"Exporting timeline: {filename}.{export_format}")
        
        export_service.timeline_service = timeline_service
        
        progress(0.5, desc="💾 Encoding audio...")
        output_path = export_service.merge_clips(
            filename=filename,
            export_format=export_format
        )
        
        if output_path:
            progress(1.0, desc="✅ Export complete!")
            return f"✅ Exported: {os.path.basename(output_path)}", output_path
        else:
            return "❌ Export failed", None
            
    except Exception as e:
        logger.error(f"Error exporting: {e}", exc_info=True)
        return f"❌ Error: {str(e)}", None

def format_duration(seconds: float) -> str:
    """Format duration as MM:SS"""
    mins = int(seconds // 60)
    secs = int(seconds % 60)
    return f"{mins}:{secs:02d}"

# Create Gradio interface
with gr.Blocks(
    title="🎵 Music Generation Studio",
    theme=gr.themes.Soft(primary_hue="purple", secondary_hue="pink")
) as app:
    
    gr.Markdown(
        """
        # 🎵 Music Generation Studio
        
        Create AI-powered music with DiffRhythm2 and LyricMind AI
        
        💡 **Tip**: Start with 10-20 second clips for faster generation on HuggingFace Spaces
        """
    )
    
    with gr.Row():
        # Left Column - Generation
        with gr.Column(scale=2):
            gr.Markdown("### 🎼 Music Generation")
            
            prompt_input = gr.Textbox(
                label="🎯 Music Prompt",
                placeholder="energetic rock song with electric guitar at 140 BPM",
                lines=3,
                info="Describe the music style, instruments, tempo, and mood"
            )
            
            lyrics_mode = gr.Radio(
                choices=["Instrumental", "User Lyrics", "Auto Lyrics"],
                value="Instrumental",
                label="🎤 Vocal Mode",
                info="Instrumental: no vocals | User: provide lyrics | Auto: AI-generated"
            )
            
            with gr.Row():
                auto_gen_btn = gr.Button("✍️ Generate Lyrics", size="sm")
            
            lyrics_input = gr.Textbox(
                label="📝 Lyrics",
                placeholder="Enter lyrics or click 'Generate Lyrics'...",
                lines=6
            )
            
            with gr.Row():
                duration_input = gr.Slider(
                    minimum=10,
                    maximum=60,
                    value=20,
                    step=5,
                    label="⏱️ Duration (seconds)",
                    info="Shorter = faster generation"
                )
                position_input = gr.Radio(
                    choices=["intro", "previous", "next", "outro"],
                    value="next",
                    label="📍 Position"
                )
            
            generate_btn = gr.Button(
                "✨ Generate Music Clip",
                variant="primary",
                size="lg"
            )
            
            gen_status = gr.Textbox(label="📊 Status", lines=3, interactive=False)
            audio_output = gr.Audio(label="🎧 Preview", type="filepath")
        
        # Right Column - Timeline
        with gr.Column(scale=1):
            gr.Markdown("### 📊 Timeline")
            
            timeline_display = gr.Textbox(
                label="Clips",
                value=get_timeline_display(),
                lines=12,
                interactive=False
            )
            
            with gr.Row():
                clip_number_input = gr.Number(
                    label="Clip #",
                    precision=0,
                    minimum=1,
                    scale=1
                )
                remove_btn = gr.Button("🗑️ Remove", size="sm", scale=1)
            
            clear_btn = gr.Button("🗑️ Clear All", variant="stop")
            timeline_status = gr.Textbox(label="Status", lines=1, interactive=False)
    
    # Export Section
    gr.Markdown("---")
    gr.Markdown("### 💾 Export")
    
    with gr.Row():
        export_filename = gr.Textbox(
            label="Filename",
            value="my_song",
            scale=2
        )
        export_format = gr.Dropdown(
            choices=["wav", "mp3"],
            value="wav",
            label="Format",
            scale=1
        )
        export_btn = gr.Button("💾 Export", variant="primary", scale=1)
    
    export_status = gr.Textbox(label="Status", lines=1, interactive=False)
    export_audio = gr.Audio(label="📥 Download", type="filepath")
    
    # Event handlers
    auto_gen_btn.click(
        fn=generate_lyrics,
        inputs=[prompt_input, duration_input],
        outputs=lyrics_input
    )
    
    generate_btn.click(
        fn=generate_music,
        inputs=[prompt_input, lyrics_input, lyrics_mode, duration_input, position_input],
        outputs=[gen_status, timeline_display, audio_output]
    )
    
    remove_btn.click(
        fn=remove_clip,
        inputs=clip_number_input,
        outputs=[timeline_status, timeline_display]
    )
    
    clear_btn.click(
        fn=clear_timeline,
        outputs=[timeline_status, timeline_display]
    )
    
    export_btn.click(
        fn=export_timeline,
        inputs=[export_filename, export_format],
        outputs=[export_status, export_audio]
    )
    
    # Help section
    with gr.Accordion("ℹ️ Help & Tips", open=False):
        gr.Markdown(
            """
            ## 🚀 Quick Start
            
            1. **Enter a prompt**: "upbeat pop song with synth at 128 BPM"
            2. **Choose mode**: Instrumental (fastest) or with vocals
            3. **Set duration**: Start with 10-20s for quick results
            4. **Generate**: Click the button and wait ~2-4 minutes
            5. **Export**: Download your complete song
            
            ## ⚡ Performance Tips
            
            - **Shorter clips = faster**: 10-20s clips generate in ~1-2 minutes
            - **Instrumental mode**: ~30% faster than with vocals
            - **HF Spaces uses CPU**: Expect 2-4 minutes per 30s clip
            - **Build incrementally**: Generate short clips, then combine
            
            ## 🎯 Prompt Tips
            
            - **Be specific**: "energetic rock with distorted guitar" > "rock song"
            - **Include BPM**: "at 140 BPM" helps set tempo
            - **Mention instruments**: "with piano and drums"
            - **Describe mood**: "melancholic", "upbeat", "aggressive"
            
            ## 🎤 Vocal Modes
            
            - **Instrumental**: Pure music, no vocals (fastest)
            - **User Lyrics**: Provide your own lyrics
            - **Auto Lyrics**: AI generates lyrics based on prompt
            
            ## 📊 Timeline
            
            - Clips are arranged sequentially
            - Remove or clear clips as needed
            - Export combines all clips into one file
            
            ---
            
            ⏱️ **Average Generation Time**: 2-4 minutes per 30-second clip on CPU
            
            🎵 **Models**: DiffRhythm2 + MuQ-MuLan + LyricMind AI
            """
        )

# Configure and launch
if __name__ == "__main__":
    logger.info("🎵 Starting Music Generation Studio on HuggingFace Spaces...")
    
    app.queue(
        default_concurrency_limit=1,
        max_size=5
    )
    
    app.launch()