<?php

namespace app\service;

use app\model\UploadFile;

/**
 * 短剧确定性配音：不再依赖 H3 原生音频猜测语言。
 */
class VideoDubService
{
    public const LANG_MANDARIN = 'zh-CN';
    public const LANG_NONE = 'none';
    public const LANG_NATIVE = 'native';
    public const AUDIO_CHARACTER = 'character_dialogue';
    public const AUDIO_NARRATION = 'narration';
    public const AUDIO_SCENE = 'scene_sound';
    public const AUDIO_AMBIENT = 'ambient_only';
    public const AUDIO_POST_TTS = 'post_tts_narration';
    public const POLICY_VERSION = 'h3-joint-av-v5';

    public static function normalizeLanguage(?string $language): string
    {
        return in_array($language, [self::LANG_MANDARIN, self::LANG_NONE, self::LANG_NATIVE], true)
            ? (string) $language
            : self::LANG_MANDARIN;
    }

    public static function label(string $language): string
    {
        return match (self::normalizeLanguage($language)) {
            self::LANG_NONE => '无配音',
            self::LANG_NATIVE => 'H3 原生音轨',
            default => '普通话（H3 原生口型同步）',
        };
    }

    public static function normalizeAudioMode(?string $mode): string
    {
        return in_array($mode, [
            self::AUDIO_CHARACTER,
            self::AUDIO_NARRATION,
            self::AUDIO_SCENE,
            self::AUDIO_AMBIENT,
            self::AUDIO_POST_TTS,
        ], true) ? (string) $mode : self::AUDIO_AMBIENT;
    }

    /**
     * @return array{id:int,processed:bool,language:string}
     */
    public static function replaceVoice(
        int $videoUploadId,
        int $userId,
        string $dialogue,
        string $language,
        int $durationSeconds = 5,
        string $placement = 'start',
        array $audioPolicy = []
    ): array {
        $language = self::normalizeLanguage($language);
        $audioMode = self::normalizeAudioMode((string) ($audioPolicy['audio_mode'] ?? self::AUDIO_AMBIENT));
        if ($language === self::LANG_NATIVE) {
            return [
                'id' => $videoUploadId,
                'processed' => false,
                'language' => $language,
                'source' => 'h3_native',
                'policy_version' => self::POLICY_VERSION,
            ];
        }
        if ($language === self::LANG_MANDARIN && $audioMode === self::AUDIO_CHARACTER) {
            // 只有画面角色对白保留 H3 联合采样原声，确保人物性别、声音和口型来自同一次生成。
            return [
                'id' => $videoUploadId,
                'processed' => false,
                'language' => $language,
                'source' => 'h3_native',
                'policy_version' => self::POLICY_VERSION,
            ];
        }
        if ($language === self::LANG_MANDARIN && $audioMode === self::AUDIO_SCENE) {
            // 场景音由 H3 与画面同次联合生成，才能让撞击、脚步、发动机等声音
            // 精确跟随动作；规划器已明确禁止该类镜头产生任何人物声音。
            return [
                'id' => $videoUploadId,
                'processed' => false,
                'language' => $language,
                'source' => 'h3_scene_sound',
                'policy_version' => self::POLICY_VERSION,
            ];
        }
        if ($language === self::LANG_MANDARIN && $audioMode === self::AUDIO_AMBIENT) {
            // H3 已经在同一次联合采样里生成与画面同步的空间底噪、动作声和
            // 环境声。旧版用极低音量粉红噪声覆盖它，最终成片约 -71dB，
            // 听感接近静音；保留原声既有声音，也不会破坏动作同步。
            return [
                'id' => $videoUploadId,
                'processed' => false,
                'language' => $language,
                'source' => 'h3_ambient',
                'policy_version' => self::POLICY_VERSION,
            ];
        }

        $video = UploadFile::where('id', $videoUploadId)
            ->where('user_id', $userId)
            ->where('file_type', 'video')
            ->find();
        if (!$video) {
            throw new \RuntimeException('无法读取待配音视频');
        }
        $videoPath = self::uploadPath($video);
        if (!is_file($videoPath)) {
            throw new \RuntimeException('待配音视频文件不存在');
        }

        $durationSeconds = max(1, min(30, $durationSeconds));
        $pcmPath = null;
        $speechTempoFilter = '';
        $voiceDelayMs = 200;
        if ($language === self::LANG_MANDARIN && $audioMode === self::AUDIO_NARRATION) {
            $spokenText = self::spokenText($dialogue);
            if ($spokenText !== '') {
                $pcmPath = tempnam(sys_get_temp_dir(), 'short_drama_tts_');
                if ($pcmPath === false) {
                    throw new \RuntimeException('无法创建普通话配音任务');
                }
                $pcm = self::synthesizeMandarin($spokenText);
                if (file_put_contents($pcmPath, $pcm) === false) {
                    @unlink($pcmPath);
                    throw new \RuntimeException('无法保存普通话配音数据');
                }
                // 24 kHz、16 bit、单声道 PCM：48000 bytes/s。超过镜头时长时加速，避免截断台词。
                $pcmDuration = strlen($pcm) / 48000;
                $targetDuration = max(0.8, $durationSeconds - 0.4);
                $tempo = max(1.0, $pcmDuration / $targetDuration);
                $speechTempoFilter = self::tempoFilter($tempo);
                $speechDuration = $pcmDuration / $tempo;
                if ($placement === 'end') {
                    $voiceDelayMs = max(200, (int) round(
                        max(0.0, $durationSeconds - $speechDuration - 0.3) * 1000
                    ));
                }
            }
        }

        $subdir = date('Y/m/d');
        $storedBase = 'dub_' . str_replace('-', '_', $language) . '_' . uniqid('', true) . '.mp4';
        $relativePath = $subdir . '/' . $storedBase;
        $fullDir = rtrim(config('upload.path'), '/\\') . DIRECTORY_SEPARATOR
            . str_replace('/', DIRECTORY_SEPARATOR, $subdir);
        if (!is_dir($fullDir) && !mkdir($fullDir, 0755, true) && !is_dir($fullDir)) {
            if ($pcmPath) {
                @unlink($pcmPath);
            }
            throw new \RuntimeException('无法创建配音视频目录');
        }
        $outputPath = $fullDir . DIRECTORY_SEPARATOR . $storedBase;

        try {
            $command = $audioMode === self::AUDIO_AMBIENT && $language !== self::LANG_NONE
                ? [
                    'ffmpeg', '-y', '-i', $videoPath,
                    '-f', 'lavfi', '-i', 'anoisesrc=color=pink:amplitude=0.006:r=48000',
                    '-filter_complex', '[1:a]highpass=f=80,lowpass=f=4800,volume=0.35,apad,atrim=0:' . $durationSeconds . '[amb]',
                    '-map', '0:v:0', '-map', '[amb]',
                    '-t', (string) $durationSeconds,
                    '-c:v', 'copy', '-c:a', 'aac', '-b:a', '128k',
                    '-movflags', '+faststart', $outputPath,
                ]
                : ($language === self::LANG_NONE || $pcmPath === null
                ? [
                    'ffmpeg', '-y', '-i', $videoPath,
                    '-f', 'lavfi', '-i', 'anullsrc=r=48000:cl=mono',
                    '-map', '0:v:0', '-map', '1:a:0',
                    '-t', (string) $durationSeconds,
                    '-c:v', 'copy', '-c:a', 'aac', '-b:a', '128k',
                    '-movflags', '+faststart', $outputPath,
                ]
                : [
                    'ffmpeg', '-y', '-i', $videoPath,
                    '-f', 's16le', '-ar', '24000', '-ac', '1', '-i', (string) $pcmPath,
                    '-filter_complex', "[1:a]aresample=48000{$speechTempoFilter},volume=2.0,alimiter=limit=0.90:level=false,adelay={$voiceDelayMs},apad,atrim=0:{$durationSeconds}[dub]",
                    '-map', '0:v:0', '-map', '[dub]',
                    '-c:v', 'copy', '-c:a', 'aac', '-b:a', '160k',
                    '-movflags', '+faststart', '-shortest', $outputPath,
                ]);
            [$exitCode, $error] = self::run($command);
            if ($exitCode !== 0 || !is_file($outputPath) || filesize($outputPath) === 0) {
                @unlink($outputPath);
                throw new \RuntimeException('普通话音轨合成失败: ' . mb_substr(trim($error), -500));
            }
        } finally {
            if ($pcmPath) {
                @unlink($pcmPath);
            }
        }

        $upload = UploadFile::create([
            'user_id' => $userId,
            'original_name' => 'short_drama_' . $language . '.mp4',
            'stored_name' => $storedBase,
            'file_path' => $relativePath,
            'mime_type' => 'video/mp4',
            'file_size' => (int) filesize($outputPath),
            'file_type' => 'video',
        ]);

        return [
            'id' => (int) $upload->id,
            'processed' => true,
            'language' => $language,
            'source' => match (true) {
                $language === self::LANG_NONE => 'silence',
                $audioMode === self::AUDIO_AMBIENT => 'clean_ambient',
                default => 'cosyvoice',
            },
            'policy_version' => self::POLICY_VERSION,
        ];
    }

    private static function tempoFilter(float $tempo): string
    {
        if ($tempo <= 1.0) {
            return '';
        }
        $filters = [];
        while ($tempo > 2.0) {
            $filters[] = 'atempo=2.0';
            $tempo /= 2.0;
        }
        $filters[] = 'atempo=' . number_format(max(1.0, $tempo), 4, '.', '');
        return ',' . implode(',', $filters);
    }

    private static function synthesizeMandarin(string $text): string
    {
        $baseUrl = rtrim((string) config('short_drama.tts_base_url'), '/');
        $promptWav = (string) config('short_drama.tts_prompt_wav');
        $promptText = (string) config('short_drama.tts_prompt_text');
        if ($baseUrl === '' || !is_file($promptWav)) {
            throw new \RuntimeException('普通话配音服务尚未配置');
        }

        $ch = curl_init($baseUrl . '/inference_zero_shot');
        curl_setopt_array($ch, [
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => [
                'tts_text' => $text,
                'prompt_text' => $promptText,
                'prompt_wav' => new \CURLFile($promptWav, 'audio/wav', 'mandarin_reference.wav'),
            ],
            CURLOPT_HTTPHEADER => ['Accept: application/octet-stream'],
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_TIMEOUT => 90,
            CURLOPT_CONNECTTIMEOUT => 5,
            CURLOPT_SSL_VERIFYPEER => false,
        ]);
        $pcm = curl_exec($ch);
        $httpCode = (int) curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $error = curl_error($ch);
        curl_close($ch);
        if ($pcm === false || $httpCode < 200 || $httpCode >= 300) {
            throw new \RuntimeException('普通话配音服务调用失败: ' . ($error ?: 'HTTP ' . $httpCode));
        }
        if (strlen((string) $pcm) < 4800) {
            throw new \RuntimeException('普通话配音服务返回空音频');
        }
        if (strlen($pcm) % 2 !== 0) {
            $pcm = substr($pcm, 0, -1);
        }
        return $pcm;
    }

    private static function spokenText(string $dialogue): string
    {
        $dialogue = trim($dialogue);
        $dialogue = preg_replace('/^[^：:]{1,16}[：:]/u', '', $dialogue) ?? $dialogue;
        return mb_substr(trim($dialogue), 0, 80);
    }

    private static function uploadPath(UploadFile $upload): string
    {
        return rtrim(config('upload.path'), '/\\') . DIRECTORY_SEPARATOR
            . str_replace('/', DIRECTORY_SEPARATOR, (string) $upload->file_path);
    }

    /** @return array{int,string} */
    private static function run(array $command): array
    {
        $pipes = [];
        $process = @proc_open($command, [
            0 => ['pipe', 'r'],
            1 => ['pipe', 'w'],
            2 => ['pipe', 'w'],
        ], $pipes);
        if (!is_resource($process)) {
            throw new \RuntimeException('服务器无法启动 FFmpeg');
        }
        fclose($pipes[0]);
        stream_get_contents($pipes[1]);
        fclose($pipes[1]);
        $error = (string) stream_get_contents($pipes[2]);
        fclose($pipes[2]);
        return [proc_close($process), $error];
    }
}