"""Shared helpers for the optional media scripts (footage, music, sound effects, voices).

Keys come from the environment and are never printed:
  GEMINI_API_KEY (or GOOGLE_API_KEY)  Google AI Studio key, for Nano Banana images and Veo video
  ELEVENLABS_API_KEY                  ElevenLabs key with Music, Sound Effects, Text to Speech
                                      and Speech to Text permissions (only the ones you use)
ffmpeg comes from ffmpeg-static in this folder (`npm install` once), or from $FFMPEG.
"""
import json
import os
import subprocess
import sys
import time
import urllib.error
import urllib.request

HERE = os.path.dirname(os.path.abspath(__file__))


def ffmpeg():
    if os.environ.get("FFMPEG"):
        return os.environ["FFMPEG"]
    try:
        return subprocess.run(["node", "-e", "console.log(require('ffmpeg-static'))"], cwd=HERE,
                              capture_output=True, text=True, check=True).stdout.strip()
    except Exception:
        sys.exit("ffmpeg not found: run `npm install` in the skill's scripts/ folder, or set FFMPEG")


def key(*names):
    for n in names:
        if os.environ.get(n):
            return os.environ[n]
    sys.exit(f"missing API key: set {' or '.join(names)} (it is read from the environment, never printed)")


def http_json(url, body=None, headers=None, timeout=300, retries=4, retry_on=(429, 500, 503), wait=20):
    """POST (or GET when body is None) and return parsed JSON, retrying on rate limits and outages."""
    data = json.dumps(body).encode() if body is not None else None
    h = {"Content-Type": "application/json", **(headers or {})}
    for attempt in range(retries + 1):
        try:
            with urllib.request.urlopen(urllib.request.Request(url, data=data, headers=h), timeout=timeout) as r:
                return json.load(r)
        except urllib.error.HTTPError as e:
            msg = e.read().decode()[:600]
            if e.code in retry_on and attempt < retries:
                print(f"  HTTP {e.code}, retrying in {wait}s", flush=True)
                time.sleep(wait)
                continue
            raise RuntimeError(f"HTTP {e.code}: {msg}") from None


def http_bytes(url, body=None, headers=None, timeout=600):
    data = json.dumps(body).encode() if body is not None else None
    h = {"Content-Type": "application/json", **(headers or {})}
    try:
        with urllib.request.urlopen(urllib.request.Request(url, data=data, headers=h), timeout=timeout) as r:
            return r.read()
    except urllib.error.HTTPError as e:
        raise RuntimeError(f"HTTP {e.code}: {e.read().decode()[:600]}") from None


def decode(path, sr=44100, mono=True, af=None):
    """Decode any audio/video file to float32 samples with numpy."""
    import numpy as np
    args = [ffmpeg(), "-v", "error", "-i", path]
    if af:
        args += ["-af", af]
    args += ["-ac", "1" if mono else "2", "-ar", str(sr), "-f", "f32le", "-"]
    return np.frombuffer(subprocess.run(args, capture_output=True, check=True).stdout, np.float32)


def lufs(path):
    import re
    err = subprocess.run([ffmpeg(), "-hide_banner", "-i", path, "-af", "apad=pad_dur=1,ebur128", "-f", "null", "-"],
                         capture_output=True, text=True).stderr
    return float(re.findall(r"I:\s+(-?[\d.]+) LUFS", err)[-1])