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#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
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import torch
from typing import Optional

from inference.common import MagiConfig, print_rank_0, set_random_seed
from inference.infra.distributed import dist_init
from inference.model.dit import get_dit

from .prompt_process import get_txt_embeddings
from .video_generate import generate_per_chunk
from .video_process import post_chunk_process, process_image, process_prefix_video, save_video_to_disk


class MagiPipeline:
    def __init__(self, config_path, residual_stats_path: Optional[str] = None, l1_rel_stats_path: Optional[str] = None):
        self.config = MagiConfig.from_json(config_path)
        self.residual_stats_path = residual_stats_path
        self.l1_rel_stats_path = l1_rel_stats_path
        set_random_seed(self.config.runtime_config.seed)
        dist_init(self.config)
        print_rank_0(self.config)

    def run_text_to_video(self, prompt: str, output_path: str):
        self._run(prompt, None, output_path)

    def run_image_to_video(self, prompt: str, image_path: str, output_path: str):
        prefix_video = process_image(image_path, self.config)
        self._run(prompt, prefix_video, output_path)

    def run_video_to_video(self, prompt: str, prefix_video_path: str, output_path: str):
        prefix_video = process_prefix_video(prefix_video_path, self.config)
        self._run(prompt, prefix_video, output_path)

    def _run(self, prompt: str, prefix_video: torch.Tensor, output_path: str):
        caption_embs, emb_masks = get_txt_embeddings(prompt, self.config) # caption_embs: [1, 1, 800, 4096], emb_masks: [1, 800]
        dit = get_dit(self.config)
        videos = torch.cat(
            [
                post_chunk_process(chunk, self.config)
                for chunk in generate_per_chunk(
                    model=dit,
                    prefix_video=prefix_video,
                    caption_embs=caption_embs,
                    emb_masks=emb_masks,
                    residual_stats_path=self.residual_stats_path,
                    l1_rel_stats_path=self.l1_rel_stats_path,
                )
            ],
            dim=0,
        )
        save_video_to_disk(videos, output_path, fps=self.config.runtime_config.fps)

        mem_allocated_gb = torch.cuda.max_memory_allocated() / 1024**3
        mem_reserved_gb = torch.cuda.max_memory_reserved() / 1024**3
        print_rank_0(
            f"Finish MagiPipeline, max memory allocated: {mem_allocated_gb:.2f} GB, max memory reserved: {mem_reserved_gb:.2f} GB"
        )