#!/usr/bin/env python3
"""Compose an instrumental score with ElevenLabs Music, section by section, timed to the edit.

  python3 music.py score.json --out music/ [--seeds 11,29]      one take per seed (max 2 run at once)
  python3 music.py --plan "prompt" --seconds 61                  print the plan ElevenLabs suggests

score.json:
  {"name": "cinematic", "bpm": 120, "model": "music_v2_5",
   "negative": ["vocals", "singing", "lyrics", "lo-fi", "muddy mix"],
   "sections": [{"tag": "[Intro]", "seconds": 6.5, "styles": ["staccato strings on eighth notes", "building momentum"]},
                {"tag": "[Impact and Breath]", "seconds": 3.0, "styles": ["huge hit on the downbeat", "sudden quiet"]}, ...]}

Each section is a composition-plan chunk with duration_ms = its seconds (min 3 s, max 120 s), so the
music changes where the film changes. "<bpm> BPM" is added to every section's styles. The total
should equal the film's length. Needs ELEVENLABS_API_KEY with the Music Generation permission
(a key without it fails with "missing the permission music_generation"); plans allow ~2 requests at once.
"""
import argparse, concurrent.futures, json, os, sys
from common import key, http_json, http_bytes

ap = argparse.ArgumentParser()
ap.add_argument("score", nargs="?"); ap.add_argument("--out", default="music"); ap.add_argument("--seeds", default="")
ap.add_argument("--plan"); ap.add_argument("--seconds", type=float, default=60); ap.add_argument("--format", default="mp3_44100_192")
a = ap.parse_args()
K = key("ELEVENLABS_API_KEY")
H = {"xi-api-key": K}

if a.plan:
    print(json.dumps(http_json("https://api.elevenlabs.io/v1/music/plan",
                               {"prompt": a.plan, "music_length_ms": int(a.seconds * 1000), "model_id": "music_v2_5"}, H), indent=1))
    sys.exit()

S = json.load(open(a.score))
os.makedirs(a.out, exist_ok=True)
total = sum(s["seconds"] for s in S["sections"])
chunks = [{"text": s["tag"], "duration_ms": int(round(s["seconds"] * 1000)),
           "positive_styles": [f"{S.get('bpm', 120)} BPM"] + s["styles"],
           "negative_styles": S.get("negative", []), "context_adherence": "high"} for s in S["sections"]]
bad = [c["text"] for c in chunks if not 3000 <= c["duration_ms"] <= 120000]
if bad:
    sys.exit(f"sections must be 3-120 s long: {bad}. Merge a short section into its neighbour and shape it in the mix.")


def take(seed):
    name = f"{S.get('name', 'score')}{'-' + str(seed) if seed else ''}"
    out = f"{a.out}/{name}.mp3"
    if os.path.exists(out): return f"{name}: exists"
    body = {"composition_plan": {"chunks": chunks}, "model_id": S.get("model", "music_v2_5"), "respect_sections_durations": True}
    if seed: body["seed"] = int(seed)
    try:
        data = http_bytes(f"https://api.elevenlabs.io/v1/music?output_format={a.format}", body, H, timeout=600)
    except RuntimeError as e:
        return f"{name}: {e}"
    open(out, "wb").write(data)
    return f"{name}: ok {len(data) // 1024} KB ({total:.1f} s planned)"


seeds = [s for s in a.seeds.split(",") if s] or [None]
with concurrent.futures.ThreadPoolExecutor(2) as ex:
    for r in ex.map(take, seeds):
        print(r, flush=True)