#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""voice 资产尾部静默审计（2026-09 句尾剪字排查的固化工具）。

用途：量化每个 voice 文件「最后一段人声能量 → 文件末尾」的静默长度，观察
生产管线的尾部裁剪松紧、发现异常文件（如 0 静默且能量戛然而止的可疑样本）。

⚠ 判读口径（2026-09 排查结论，勿推翻）：
  - 本项目 TTS 管线峰值归一 + 静音尾裁剪很紧，**绝大多数文件尾部静默 <120ms
    属预期**，不等于剪字。tail 静默长度不能单独作为「句尾被剪」的证据。
  - 「句子是否读完」的验收在**引擎层**（voice 自然结束以源消耗位置判定 +
    300ms 管线排空，见 web/engine/audio.js _finishVoice 与
    web/harness/engine-voice.test.mjs），不在资产层。
  - 资产侧怀疑剪字时，用 SenseVoice ASR 抽查可疑文件并核对末字/语气词
    （管线：.venv-asr/bin/python，参照 research/new8 排查记录）。

用法：
  .venv-tts/bin/python tools/audit_voice_tails.py            # 全部 8 游戏
  .venv-tts/bin/python tools/audit_voice_tails.py --tail-min 0.08
"""
import argparse
import array
import os
import subprocess

ROOT = os.environ.get(
    "SG_ROOT",
    os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__)))),
)
FF = os.path.join(ROOT, "tools", "bin", "ffmpeg")
WEB = os.path.join(ROOT, "web")
GAMES = ["storyline", "escape", "simon", "rhythm", "space", "rpg", "radio", "dungeon"]

ap = argparse.ArgumentParser(description="voice 资产尾部静默审计")
ap.add_argument("--tail-min", type=float, default=0.120,
                help="尾部静默阈值（秒），低于此列入报告（默认 0.120）")
TAIL_MIN = ap.parse_args().tail_min


def profile(path):
    """解码 16k mono pcm_s16le，返回 (dur, head_sil, tail_sil) 秒。"""
    p = subprocess.run([FF, "-v", "error", "-i", path, "-ac", "1", "-ar", "16000",
                        "-f", "s16le", "-"], capture_output=True)
    data = p.stdout
    if len(data) < 3200:
        return None
    a = array.array('h')
    a.frombytes(data)
    n = len(a)
    win = 320  # 20ms @16k

    def rms(i):
        seg = a[i:i + win]
        return (sum(x * x for x in seg) / win) ** 0.5

    last, first = -1, -1
    for i in range(0, n - win, win):
        if rms(i) > 500:  # ≈ -30dBFS 记为有人声
            if first < 0:
                first = i
            last = i
    if last < 0:
        return None
    dur = n / 16000.0
    tail = (n - (last + win)) / 16000.0
    head = first / 16000.0
    return dur, head, tail


def main():
    bad, total = [], 0
    for g in GAMES:
        vdir = os.path.join(WEB, g, "audio", "voice")
        for dp, _dn, fs in os.walk(vdir):
            for f in fs:
                if not f.endswith((".ogg", ".m4a")):
                    continue
                total += 1
                r = profile(os.path.join(dp, f))
                if not r:
                    continue
                dur, _head, tail = r
                if tail < TAIL_MIN:
                    bad.append((os.path.relpath(os.path.join(dp, f), WEB), dur, tail))
    print(f"scanned {total} voice files")
    print(f"tail silence < {int(TAIL_MIN*1000)}ms: {len(bad)}（判读口径见文件头注）")
    for rel, dur, tail in sorted(bad, key=lambda x: x[2])[:40]:
        print(f"  tail={int(tail*1000):4d}ms dur={dur:5.2f}s {rel}")


if __name__ == "__main__":
    main()