app.py

#!/usr/bin/env python3
"""
GhostAI Music Generator – ZeroGPU Edition
• Streams facebook/musicgen-medium from the Hub using your HF_TOKEN
• Runs on a transient GPU provided by the ZeroGPU scheduler
• Keeps your genre prompt builders, EQ / fade FX, neon Gradio UI
"""

# ── ZeroGPU decorator must be imported *before* torch/CUDA ──────────
import spaces                                  # 👈 FIRST import

# ── Standard libs ───────────────────────────────────────────────────
import os, sys, gc, time, random, warnings, tempfile
import numpy as np, psutil

# ── Torch (CPU wheels; ZeroGPU moves tensors to the temp GPU) ───────
import torch, torchaudio

# ── Other deps ──────────────────────────────────────────────────────
import gradio as gr
from pydub import AudioSegment
from audiocraft.models import MusicGen
from huggingface_hub import login
from torch.cuda.amp import autocast

# ── Torch <2.3 shim (transformers 4.35 calls get_default_device) ───
if not hasattr(torch, "get_default_device"):
    torch.get_default_device = lambda: torch.device(
        "cuda" if torch.cuda.is_available() else "cpu"
    )

warnings.filterwarnings("ignore")
os.environ["PYTORCH_CUDA_ALLOC_CONF"] = "max_split_size_mb:128"

# ────────────────────────── HF authentication ──────────────────────
HF_TOKEN = os.getenv("HF_TOKEN")
if not HF_TOKEN:
    sys.exit("ERROR: add HF_TOKEN as a secret in your Space settings.")
login(HF_TOKEN)

print("🔄  Loading facebook/musicgen-medium (first build ≈ 6 GB)…")
musicgen = MusicGen.get_pretrained("facebook/musicgen-medium")
musicgen.to(torch.get_default_device())            # move entire model
musicgen.set_generation_params(duration=10, two_step_cfg=False)
SR = musicgen.sample_rate

# ────────────────────────── Prompt helpers ─────────────────────────
def _p(base,bpm,dr,syn,st,bass,gtr,db,dg,flow):
    step = f" with {st}" if st!="none" else flow.format(bpm=bpm)
    return (f"{base}"
            f"{', '+bass if bass!='none' else db}"
            f"{', '+gtr+' guitar riffs' if gtr!='none' else dg}"
            f"{', '+dr+' drums' if dr!='none' else ''}"
            f"{', '+syn+' accents' if syn!='none' else ''}"
            f"{step} at {bpm} BPM.")

def set_red_hot_chili_peppers_prompt(bpm,dr,syn,st,bass,gtr):
    return _p("Instrumental funk rock",bpm,dr,syn,st,bass,gtr,
              ", groovy basslines",", syncopated guitar riffs",
              "{bpm} BPM funky flow" if bpm>120 else "groovy rhythmic flow")
def set_nirvana_grunge_prompt(bpm,dr,syn,st,bass,gtr):
    return _p("Instrumental grunge",bpm,dr,syn,st,bass,gtr,
              ", melodic basslines",", raw distorted guitar riffs",
              "{bpm} BPM grungy pulse" if bpm>120 else "grungy rhythmic pulse")
# 👉 add your other genre prompt functions here exactly as before …

# ────────────────────────── Audio FX helpers ───────────────────────
def apply_eq(s):   return s.low_pass_filter(8000).high_pass_filter(80)
def apply_fade(s): return s.fade_in(1000).fade_out(1000)

def log(stage=""):
    if stage: print(f"── {stage} ──")
    if torch.cuda.is_available():
        a = torch.cuda.memory_allocated()/1024**3
        r = torch.cuda.memory_reserved()/1024**3
        print(f"GPU mem alloc {a:.2f} GB  reserved {r:.2f} GB")
    print(f"CPU mem {psutil.virtual_memory().percent}% used")

# ──────────────────────── Core generator API ───────────────────────
@spaces.GPU                     # 🟢 ZeroGPU will allocate a GPU per call
def generate_music(prompt,cfg,k,p,temp,
                   total_len,chunk_len,xfade,
                   bpm,dr,syn,step,bass,gtr):

    if not prompt.strip():
        return None, "⚠️ Prompt is empty."

    total_len  = int(total_len)
    chunk_len  = max(5, min(int(chunk_len), 15))
    n_chunks   = max(1, total_len // chunk_len)
    chunk_len  = total_len / n_chunks
    overlap    = min(1.0, xfade / 1000.0)
    render_len = chunk_len + overlap
    pieces     = []

    torch.manual_seed(42); np.random.seed(42)
    t0 = time.time()

    for i in range(n_chunks):
        log(f"before chunk {i+1}")
        musicgen.set_generation_params(
            duration=render_len, use_sampling=True,
            top_k=k, top_p=p, temperature=temp, cfg_coef=cfg
        )
        with torch.no_grad(), autocast():
            audio = musicgen.generate([prompt], progress=False)[0]

        audio = audio.cpu().float()
        if audio.dim()==1 or audio.shape[0]==1:
            audio = audio.repeat(2,1)
        with tempfile.NamedTemporaryFile(suffix=".wav", delete=False) as tmp:
            torchaudio.save(tmp.name, audio, SR)
            seg = AudioSegment.from_wav(tmp.name)
        os.unlink(tmp.name)
        pieces.append(seg)

        torch.cuda.empty_cache(); gc.collect()
        log(f"after chunk {i+1}")

    track = pieces[0]
    for seg in pieces[1:]:
        track = track.append(seg, crossfade=xfade)
    track = track[: total_len*1000]
    track = apply_fade(apply_eq(track).normalize(headroom=-9.0))

    out_path = "output_cleaned.mp3"
    track.export(out_path, format="mp3", bitrate="128k",
                 tags={"title":"GhostAI Track","artist":"GhostAI"})
    log("final"); print(f"⏱  {time.time()-t0:.1f}s total")
    return out_path, "✅ Done!"

def clear_inputs():
    return ("",3.0,250,0.9,1.0,30,10,1000,
            120,"none","none","none","none","none")

# ────────────────────────── Gradio UI ──────────────────────────────
css = "body{background:#0A0A0A;color:#E0E0E0;font-family:'Orbitron',sans-serif}"

with gr.Blocks(css=css) as demo:
    gr.HTML("<h1 style='text-align:center'>👻 GhostAI Music Generator</h1>")
    prompt = gr.Textbox(lines=4, label="Instrumental Prompt")
    with gr.Row():
        gr.Button("RHCP 🌶️").click(set_red_hot_chili_peppers_prompt,
            inputs=[gr.State(120),"none","none","none","none","none"],
            outputs=prompt)
        gr.Button("Nirvana 🎸").click(set_nirvana_grunge_prompt,
            inputs=[gr.State(120),"none","none","none","none","none"],
            outputs=prompt)
        # 📌 add remaining genre buttons here …

    cfg   = gr.Slider(1,10,3,label="CFG Scale")
    top_k = gr.Slider(10,500,250,step=10,label="Top-K")
    top_p = gr.Slider(0,1,0.9,step=0.05,label="Top-P")
    temp  = gr.Slider(0.1,2,1,step=0.1,label="Temperature")
    length= gr.Radio([30,60,90,120], value=30, label="Length (s)")
    chunk = gr.Slider(5,15,10,step=1,label="Chunk (s)")
    xfade = gr.Slider(100,2000,1000,step=100,label="Cross-fade (ms)")

    bpm   = gr.Slider(60,180,120,label="BPM")
    drum  = gr.Dropdown(["none","standard rock","funk groove","techno kick","jazz swing"],"none","Drum")
    synth = gr.Dropdown(["none","analog synth","digital pad","arpeggiated synth"],"none","Synth")
    steps = gr.Dropdown(["none","syncopated steps","steady steps","complex steps"],"none","Steps")
    bass  = gr.Dropdown(["none","slap bass","deep bass","melodic bass"],"none","Bass")
    gtr   = gr.Dropdown(["none","distorted","clean","jangle"],"none","Guitar")

    gen = gr.Button("Generate 🚀")
    clr = gr.Button("Clear 🧹")
    audio_out = gr.Audio(type="filepath")
    status    = gr.Textbox(interactive=False)

    gen.click(generate_music,
              inputs=[prompt,cfg,top_k,top_p,temp,length,chunk,xfade,
                      bpm,drum,synth,steps,bass,gtr],
              outputs=[audio_out,status])
    clr.click(clear_inputs,None,
              [prompt,cfg,top_k,top_p,temp,length,chunk,xfade,
               bpm,drum,synth,steps,bass,gtr])

demo.launch(share=False)