ltx_manager_helpers.py

# ltx_manager_helpers.py
# Copyright (C) 4 de Agosto de 2025  Carlos Rodrigues dos Santos
#
# Este programa é software livre: você pode redistribuí-lo e/ou modificá-lo
# sob os termos da Licença Pública Geral Affero GNU...
# AVISO DE PATENTE PENDENTE: Consulte NOTICE.md.

import torch
import gc
import os
import yaml
import logging
import huggingface_hub
import time
import threading
import json
from typing import Optional, List

from optimization import optimize_ltx_worker, can_optimize_fp8
from hardware_manager import hardware_manager
from inference import create_ltx_video_pipeline, calculate_padding
from ltx_video.pipelines.pipeline_ltx_video import LatentConditioningItem, LTXMultiScalePipeline

logger = logging.getLogger(__name__)

class LtxWorker:
    """
    Representa uma única instância da pipeline LTX-Video em um dispositivo específico.
    Gerencia o carregamento do modelo para a CPU e a movimentação de/para a GPU.
    """
    def __init__(self, device_id, ltx_config_file):
        self.cpu_device = torch.device('cpu')
        self.device = torch.device(device_id if torch.cuda.is_available() else 'cpu')
        logger.info(f"LTX Worker ({self.device}): Inicializando com config '{ltx_config_file}'...")
        
        with open(ltx_config_file, "r") as file:
            self.config = yaml.safe_load(file)
        
        self.is_distilled = "distilled" in self.config.get("checkpoint_path", "")

        models_dir = "downloaded_models_gradio"
        
        logger.info(f"LTX Worker ({self.device}): Carregando modelo para a CPU...")
        model_path = os.path.join(models_dir, self.config["checkpoint_path"])
        if not os.path.exists(model_path):
             model_path = huggingface_hub.hf_hub_download(
                repo_id="Lightricks/LTX-Video", filename=self.config["checkpoint_path"],
                local_dir=models_dir, local_dir_use_symlinks=False
            )
        
        self.pipeline = create_ltx_video_pipeline(
            ckpt_path=model_path, precision=self.config["precision"],
            text_encoder_model_name_or_path=self.config["text_encoder_model_name_or_path"],
            sampler=self.config["sampler"], device='cpu'
        )
        logger.info(f"LTX Worker ({self.device}): Modelo pronto na CPU. É um modelo destilado? {self.is_distilled}")

    def to_gpu(self):
        """Move o pipeline para a GPU designada E OTIMIZA SE POSSÍVEL."""
        if self.device.type == 'cpu': return
        logger.info(f"LTX Worker: Movendo pipeline para a GPU {self.device}...")
        self.pipeline.to(self.device)
        
        if self.device.type == 'cuda' and can_optimize_fp8():
            logger.info(f"LTX Worker ({self.device}): GPU com suporte a FP8 detectada. Iniciando otimização...")
            optimize_ltx_worker(self)
            logger.info(f"LTX Worker ({self.device}): Otimização concluída.")
        elif self.device.type == 'cuda':
            logger.info(f"LTX Worker ({self.device}): Otimização FP8 não suportada ou desativada.")

    def to_cpu(self):
        """Move o pipeline de volta para a CPU e libera a memória da GPU."""
        if self.device.type == 'cpu': return
        logger.info(f"LTX Worker: Descarregando pipeline da GPU {self.device}...")
        self.pipeline.to('cpu')
        gc.collect()
        if torch.cuda.is_available(): torch.cuda.empty_cache()

    def generate_video_fragment_internal(self, **kwargs):
        """Invoca a pipeline de geração."""
        return self.pipeline(**kwargs).images

class LtxPoolManager:
    """
    Gerencia um pool de LtxWorkers para otimizar o uso de múltiplas GPUs.
    MODO "HOT START": Mantém todos os modelos carregados na VRAM para latência mínima.
    """
    def __init__(self, device_ids, ltx_config_file):
        logger.info(f"LTX POOL MANAGER: Criando workers para os dispositivos: {device_ids}")
        self.workers = [LtxWorker(dev_id, ltx_config_file) for dev_id in device_ids]
        self.current_worker_index = 0
        self.lock = threading.Lock()

        if all(w.device.type == 'cuda' for w in self.workers):
            logger.info("LTX POOL MANAGER: MODO HOT START ATIVADO. Pré-aquecendo todas as GPUs...")
            for worker in self.workers:
                worker.to_gpu()
            logger.info("LTX POOL MANAGER: Todas as GPUs estão quentes e prontas.")
        else:
            logger.info("LTX POOL MANAGER: Operando em modo CPU ou misto. O pré-aquecimento de GPU foi ignorado.")

    def _get_next_worker(self):
        with self.lock:
            worker = self.workers[self.current_worker_index]
            self.current_worker_index = (self.current_worker_index + 1) % len(self.workers)
            return worker
    
    def _prepare_pipeline_params(self, worker: LtxWorker, **kwargs) -> dict:
        """Prepara o dicionário de parâmetros para a pipeline, tratando casos especiais como modelos destilados."""
        pipeline_params = {
            "height": kwargs['height'], "width": kwargs['width'], "num_frames": kwargs['video_total_frames'],
            "frame_rate": kwargs.get('video_fps', 24),
            "generator": torch.Generator(device=worker.device).manual_seed(int(time.time()) + kwargs.get('current_fragment_index', 0)),
            "is_video": True, "vae_per_channel_normalize": True,
            "prompt": kwargs.get('motion_prompt', ""), "negative_prompt": kwargs.get('negative_prompt', "blurry, distorted, static, bad quality"),
            "guidance_scale": kwargs.get('guidance_scale', 1.0), "stg_scale": kwargs.get('stg_scale', 0.0),
            "rescaling_scale": kwargs.get('rescaling_scale', 0.15), "num_inference_steps": kwargs.get('num_inference_steps', 20),
            "output_type": "latent"
        }

        if 'latents' in kwargs:
            pipeline_params["latents"] = kwargs['latents'].to(worker.device, dtype=worker.pipeline.transformer.dtype)
        if 'strength' in kwargs:
            pipeline_params["strength"] = kwargs['strength']
        if 'conditioning_items_data' in kwargs:
            final_conditioning_items = []
            for item in kwargs['conditioning_items_data']:
                item.latent_tensor = item.latent_tensor.to(worker.device)
                final_conditioning_items.append(item)
            pipeline_params["conditioning_items"] = final_conditioning_items

        if worker.is_distilled:
            logger.info(f"Worker {worker.device} está usando um modelo destilado. Usando timesteps fixos.")
            fixed_timesteps = worker.config.get("first_pass", {}).get("timesteps")
            pipeline_params["timesteps"] = fixed_timesteps
            if fixed_timesteps:
                pipeline_params["num_inference_steps"] = len(fixed_timesteps)
        
        return pipeline_params

    def generate_latent_fragment(self, **kwargs) -> (torch.Tensor, tuple):
        worker_to_use = self._get_next_worker()
        try:
            # [CORREÇÃO] A lógica de padding é específica para a geração do zero.
            height, width = kwargs['height'], kwargs['width']
            padded_h, padded_w = ((height - 1) // 32 + 1) * 32, ((width - 1) // 32 + 1) * 32
            padding_vals = calculate_padding(height, width, padded_h, padded_w)
            kwargs['height'], kwargs['width'] = padded_h, padded_w

            pipeline_params = self._prepare_pipeline_params(worker_to_use, **kwargs)
            
            logger.info(f"Iniciando GERAÇÃO em {worker_to_use.device} com shape {padded_w}x{padded_h}")

            if isinstance(worker_to_use.pipeline, LTXMultiScalePipeline):
                result = worker_to_use.pipeline.video_pipeline(**pipeline_params).images
            else:
                result = worker_to_use.generate_video_fragment_internal(**pipeline_params)
            
            return result, padding_vals
        except Exception as e:
            logger.error(f"LTX POOL MANAGER: Erro durante a geração em {worker_to_use.device}: {e}", exc_info=True)
            raise e
        finally:
            if worker_to_use and worker_to_use.device.type == 'cuda':
                with torch.cuda.device(worker_to_use.device):
                    gc.collect(); torch.cuda.empty_cache()

    def refine_latents(self, latents_to_refine: torch.Tensor, **kwargs) -> (torch.Tensor, tuple):
        worker_to_use = self._get_next_worker()
        try:
            # [CORREÇÃO] A lógica de dimensionamento para refinamento deriva da forma do latente.
            _b, _c, _f, latent_h, latent_w = latents_to_refine.shape
            vae_scale_factor = worker_to_use.pipeline.vae_scale_factor
            
            # Garante que as dimensões correspondam EXATAMENTE ao latente fornecido.
            kwargs['height'] = latent_h * vae_scale_factor
            kwargs['width'] = latent_w * vae_scale_factor
            kwargs['video_total_frames'] = kwargs.get('video_total_frames', _f * worker_to_use.pipeline.video_scale_factor)
            kwargs['latents'] = latents_to_refine
            kwargs['strength'] = kwargs.get('denoise_strength', 0.4)
            kwargs['num_inference_steps'] = int(kwargs.get('refine_steps', 10))
            
            pipeline_params = self._prepare_pipeline_params(worker_to_use, **kwargs)

            logger.info(f"Iniciando REFINAMENTO em {worker_to_use.device} com shape {kwargs['width']}x{kwargs['height']}")
            
            pipeline_to_call = worker_to_use.pipeline.video_pipeline if isinstance(worker_to_use.pipeline, LTXMultiScalePipeline) else worker_to_use.pipeline
            result = pipeline_to_call(**pipeline_params).images
            return result, None
        
        except torch.cuda.OutOfMemoryError as e:
            logger.error(f"FALHA DE MEMÓRIA DURANTE O REFINAMENTO em {worker_to_use.device}: {e}")
            logger.warning("Limpando VRAM e retornando None para sinalizar a falha.")
            gc.collect(); torch.cuda.empty_cache()
            return None, None
        except Exception as e:
            logger.error(f"LTX POOL MANAGER: Erro inesperado durante o refinamento em {worker_to_use.device}: {e}", exc_info=True)
            raise e
        finally:
            if worker_to_use and worker_to_use.device.type == 'cuda':
                with torch.cuda.device(worker_to_use.device):
                    gc.collect(); torch.cuda.empty_cache()

# --- Instanciação Singleton ---
logger.info("Lendo config.yaml para inicializar o LTX Pool Manager...")
with open("config.yaml", 'r') as f:
    config = yaml.safe_load(f)
ltx_gpus_required = config['specialists']['ltx']['gpus_required']
ltx_device_ids = hardware_manager.allocate_gpus('LTX', ltx_gpus_required)
ltx_config_path = config['specialists']['ltx']['config_file']
ltx_manager_singleton = LtxPoolManager(device_ids=ltx_device_ids, ltx_config_file=ltx_config_path)
logger.info("Especialista de Vídeo (LTX) pronto.")