# SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
#
# 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
# limitations under the License.

import argparse
import importlib
from contextlib import contextmanager
from typing import List, NamedTuple, Optional, Tuple

import einops
import imageio
import numpy as np
import torch
import torchvision.transforms.functional as transforms_F

from cosmos_predict1.diffusion.model.model_t2w import DiffusionT2WModel
from cosmos_predict1.diffusion.model.model_v2w import DiffusionV2WModel
from cosmos_predict1.diffusion.model.model_v2w_multiview import DiffusionMultiviewV2WModel
from cosmos_predict1.utils import log
from cosmos_predict1.utils.config_helper import get_config_module, override
from cosmos_predict1.utils.io import load_from_fileobj

TORCH_VERSION: Tuple[int, ...] = tuple(int(x) for x in torch.__version__.split(".")[:2])
if TORCH_VERSION >= (1, 11):
    from torch.ao import quantization
    from torch.ao.quantization import FakeQuantizeBase, ObserverBase
elif (
    TORCH_VERSION >= (1, 8)
    and hasattr(torch.quantization, "FakeQuantizeBase")
    and hasattr(torch.quantization, "ObserverBase")
):
    from torch import quantization
    from torch.quantization import FakeQuantizeBase, ObserverBase

DEFAULT_AUGMENT_SIGMA = 0.001


def add_common_arguments(parser):
    """Add common command line arguments for text2world and video2world generation.

    Args:
        parser (ArgumentParser): Argument parser to add arguments to

    The arguments include:
    - checkpoint_dir: Base directory containing model weights
    - tokenizer_dir: Directory containing tokenizer weights
    - video_save_name: Output video filename for single video generation
    - video_save_folder: Output directory for batch video generation
    - prompt: Text prompt for single video generation
    - batch_input_path: Path to JSONL file with input prompts for batch video generation
    - negative_prompt: Text prompt describing undesired attributes
    - num_steps: Number of diffusion sampling steps
    - guidance: Classifier-free guidance scale
    - num_video_frames: Number of frames to generate
    - height/width: Output video dimensions
    - fps: Output video frame rate
    - seed: Random seed for reproducibility
    - Various model offloading flags
    """
    parser.add_argument(
        "--checkpoint_dir", type=str, default="checkpoints", help="Base directory containing model checkpoints"
    )
    parser.add_argument(
        "--tokenizer_dir",
        type=str,
        default="Cosmos-Tokenize1-CV8x8x8-720p",
        help="Tokenizer weights directory relative to checkpoint_dir",
    )
    parser.add_argument(
        "--video_save_name",
        type=str,
        default="output",
        help="Output filename for generating a single video",
    )
    parser.add_argument(
        "--video_save_folder",
        type=str,
        default="outputs/",
        help="Output folder for generating a batch of videos",
    )
    parser.add_argument(
        "--prompt",
        type=str,
        help="Text prompt for generating a single video",
    )
    parser.add_argument(
        "--batch_input_path",
        type=str,
        help="Path to a JSONL file of input prompts for generating a batch of videos",
    )
    parser.add_argument(
        "--negative_prompt",
        type=str,
        default="The video captures a series of frames showing ugly scenes, static with no motion, motion blur, "
        "over-saturation, shaky footage, low resolution, grainy texture, pixelated images, poorly lit areas, "
        "underexposed and overexposed scenes, poor color balance, washed out colors, choppy sequences, "
        "jerky movements, low frame rate, artifacting, color banding, unnatural transitions, outdated special "
        "effects, fake elements, unconvincing visuals, poorly edited content, jump cuts, visual noise, and "
        "flickering. Overall, the video is of poor quality.",
        help="Negative prompt for the video",
    )
    parser.add_argument("--num_steps", type=int, default=35, help="Number of diffusion sampling steps")
    parser.add_argument("--guidance", type=float, default=7, help="Guidance scale value")
    parser.add_argument(
        "--num_video_frames", type=int, default=121, choices=[121], help="Number of video frames to sample"
    )
    parser.add_argument("--height", type=int, default=704, help="Height of video to sample")
    parser.add_argument("--width", type=int, default=1280, help="Width of video to sample")
    parser.add_argument("--fps", type=int, default=24, help="FPS of the sampled video")
    parser.add_argument("--seed", type=int, default=1, help="Random seed")
    parser.add_argument("--num_gpus", type=int, default=1, help="Number of GPUs used to run inference in parallel.")
    parser.add_argument(
        "--disable_prompt_upsampler",
        action="store_true",
        help="Disable prompt upsampling",
    )
    parser.add_argument(
        "--offload_diffusion_transformer",
        action="store_true",
        help="Offload DiT after inference",
    )
    parser.add_argument(
        "--offload_tokenizer",
        action="store_true",
        help="Offload tokenizer after inference",
    )
    parser.add_argument(
        "--offload_text_encoder_model",
        action="store_true",
        help="Offload text encoder model after inference",
    )
    parser.add_argument(
        "--offload_prompt_upsampler",
        action="store_true",
        help="Offload prompt upsampler after inference",
    )
    parser.add_argument(
        "--offload_guardrail_models",
        action="store_true",
        help="Offload guardrail models after inference",
    )
    parser.add_argument(
        "--disable_guardrail",
        action="store_true",
        help="Disable guardrail models",
    )


# Function to fully remove an argument
def remove_argument(parser, arg_name):
    # Get a list of actions to remove
    actions_to_remove = [action for action in parser._actions if action.dest == arg_name]

    for action in actions_to_remove:
        # Remove action from parser._actions
        parser._actions.remove(action)

        # Remove option strings
        for option_string in action.option_strings:
            parser._option_string_actions.pop(option_string, None)


def validate_args(args: argparse.Namespace, inference_type: str) -> None:
    """Validate command line arguments for text2world and video2world generation."""
    assert inference_type in [
        "text2world",
        "video2world",
    ], "Invalid inference_type, must be 'text2world' or 'video2world'"

    # Validate prompt/image/video args for single or batch generation
    if inference_type == "text2world" or (inference_type == "video2world" and args.disable_prompt_upsampler):
        assert args.prompt or args.batch_input_path, "--prompt or --batch_input_path must be provided."
    if inference_type == "video2world" and not args.batch_input_path:
        assert (
            args.input_image_or_video_path
        ), "--input_image_or_video_path must be provided for single video generation."


class _IncompatibleKeys(
    NamedTuple(
        "IncompatibleKeys",
        [
            ("missing_keys", List[str]),
            ("unexpected_keys", List[str]),
            ("incorrect_shapes", List[Tuple[str, Tuple[int], Tuple[int]]]),
        ],
    )
):
    pass


def non_strict_load_model(model: torch.nn.Module, checkpoint_state_dict: dict) -> _IncompatibleKeys:
    """Load a model checkpoint with non-strict matching, handling shape mismatches.

    Args:
        model (torch.nn.Module): Model to load weights into
        checkpoint_state_dict (dict): State dict from checkpoint

    Returns:
        _IncompatibleKeys: Named tuple containing:
            - missing_keys: Keys present in model but missing from checkpoint
            - unexpected_keys: Keys present in checkpoint but not in model
            - incorrect_shapes: Keys with mismatched tensor shapes

    The function handles special cases like:
    - Uninitialized parameters
    - Quantization observers
    - TransformerEngine FP8 states
    """
    # workaround https://github.com/pytorch/pytorch/issues/24139
    model_state_dict = model.state_dict()
    incorrect_shapes = []
    for k in list(checkpoint_state_dict.keys()):
        if k in model_state_dict:
            if "_extra_state" in k:  # Key introduced by TransformerEngine for FP8
                log.debug(f"Skipping key {k} introduced by TransformerEngine for FP8 in the checkpoint.")
                continue
            model_param = model_state_dict[k]
            # Allow mismatch for uninitialized parameters
            if TORCH_VERSION >= (1, 8) and isinstance(model_param, torch.nn.parameter.UninitializedParameter):
                continue
            if not isinstance(model_param, torch.Tensor):
                raise ValueError(
                    f"Find non-tensor parameter {k} in the model. type: {type(model_param)} {type(checkpoint_state_dict[k])}, please check if this key is safe to skip or not."
                )

            shape_model = tuple(model_param.shape)
            shape_checkpoint = tuple(checkpoint_state_dict[k].shape)
            if shape_model != shape_checkpoint:
                has_observer_base_classes = (
                    TORCH_VERSION >= (1, 8)
                    and hasattr(quantization, "ObserverBase")
                    and hasattr(quantization, "FakeQuantizeBase")
                )
                if has_observer_base_classes:
                    # Handle the special case of quantization per channel observers,
                    # where buffer shape mismatches are expected.
                    def _get_module_for_key(model: torch.nn.Module, key: str) -> torch.nn.Module:
                        # foo.bar.param_or_buffer_name -> [foo, bar]
                        key_parts = key.split(".")[:-1]
                        cur_module = model
                        for key_part in key_parts:
                            cur_module = getattr(cur_module, key_part)
                        return cur_module

                    cls_to_skip = (
                        ObserverBase,
                        FakeQuantizeBase,
                    )
                    target_module = _get_module_for_key(model, k)
                    if isinstance(target_module, cls_to_skip):
                        # Do not remove modules with expected shape mismatches
                        # them from the state_dict loading. They have special logic
                        # in _load_from_state_dict to handle the mismatches.
                        continue

                incorrect_shapes.append((k, shape_checkpoint, shape_model))
                checkpoint_state_dict.pop(k)
    incompatible = model.load_state_dict(checkpoint_state_dict, strict=False)
    # Remove keys with "_extra_state" suffix, which are non-parameter items introduced by TransformerEngine for FP8 handling
    missing_keys = [k for k in incompatible.missing_keys if "_extra_state" not in k]
    unexpected_keys = [k for k in incompatible.unexpected_keys if "_extra_state" not in k]
    return _IncompatibleKeys(
        missing_keys=missing_keys,
        unexpected_keys=unexpected_keys,
        incorrect_shapes=incorrect_shapes,
    )


@contextmanager
def skip_init_linear():
    # skip init of nn.Linear
    orig_reset_parameters = torch.nn.Linear.reset_parameters
    torch.nn.Linear.reset_parameters = lambda x: x
    xavier_uniform_ = torch.nn.init.xavier_uniform_
    torch.nn.init.xavier_uniform_ = lambda x: x
    yield
    torch.nn.Linear.reset_parameters = orig_reset_parameters
    torch.nn.init.xavier_uniform_ = xavier_uniform_


def load_model_by_config(
    config_job_name,
    config_file="projects/cosmos_video/config/config.py",
    model_class=DiffusionT2WModel,
):
    config_module = get_config_module(config_file)
    config = importlib.import_module(config_module).make_config()

    config = override(config, ["--", f"experiment={config_job_name}"])

    # Check that the config is valid
    config.validate()
    # Freeze the config so developers don't change it during training.
    config.freeze()  # type: ignore

    # Initialize model
    with skip_init_linear():
        model = model_class(config.model)
    return model


def load_network_model(model: DiffusionT2WModel, ckpt_path: str):
    with skip_init_linear():
        model.set_up_model()
    try:
        net_state_dict = torch.load(ckpt_path, map_location="cpu", weights_only=True)
    except Exception:
        # Posttrained models can be loaded with weights_only=False
        net_state_dict = torch.load(ckpt_path, map_location="cpu", weights_only=False)
    log.debug(non_strict_load_model(model.model, net_state_dict))
    model.cuda()


def load_tokenizer_model(model: DiffusionT2WModel, tokenizer_dir: str):
    with skip_init_linear():
        model.set_up_tokenizer(tokenizer_dir)
    model.cuda()


def prepare_data_batch(
    height: int,
    width: int,
    num_frames: int,
    fps: int,
    prompt_embedding: torch.Tensor,
    negative_prompt_embedding: Optional[torch.Tensor] = None,
):
    """Prepare input batch tensors for video generation.

    Args:
        height (int): Height of video frames
        width (int): Width of video frames
        num_frames (int): Number of frames to generate
        fps (int): Frames per second
        prompt_embedding (torch.Tensor): Encoded text prompt embeddings
        negative_prompt_embedding (torch.Tensor, optional): Encoded negative prompt embeddings

    Returns:
        dict: Batch dictionary containing:
            - video: Zero tensor of target video shape
            - t5_text_mask: Attention mask for text embeddings
            - image_size: Target frame dimensions
            - fps: Target frame rate
            - num_frames: Number of frames
            - padding_mask: Frame padding mask
            - t5_text_embeddings: Prompt embeddings
            - neg_t5_text_embeddings: Negative prompt embeddings (if provided)
            - neg_t5_text_mask: Mask for negative embeddings (if provided)
    """
    # Create base data batch
    data_batch = {
        "video": torch.zeros((1, 3, num_frames, height, width), dtype=torch.uint8).cuda(),
        "t5_text_mask": torch.ones(1, 512, dtype=torch.bfloat16).cuda(),
        "image_size": torch.tensor([[height, width, height, width]] * 1, dtype=torch.bfloat16).cuda(),
        "fps": torch.tensor([fps] * 1, dtype=torch.bfloat16).cuda(),
        "num_frames": torch.tensor([num_frames] * 1, dtype=torch.bfloat16).cuda(),
        "padding_mask": torch.zeros((1, 1, height, width), dtype=torch.bfloat16).cuda(),
    }

    # Handle text embeddings

    t5_embed = prompt_embedding.to(dtype=torch.bfloat16).cuda()
    data_batch["t5_text_embeddings"] = t5_embed

    if negative_prompt_embedding is not None:
        neg_t5_embed = negative_prompt_embedding.to(dtype=torch.bfloat16).cuda()
        data_batch["neg_t5_text_embeddings"] = neg_t5_embed
        data_batch["neg_t5_text_mask"] = torch.ones(1, 512, dtype=torch.bfloat16).cuda()

    return data_batch


def get_video_batch(model, prompt_embedding, negative_prompt_embedding, height, width, fps, num_video_frames):
    """Prepare complete input batch for video generation including latent dimensions.

    Args:
        model: Diffusion model instance
        prompt_embedding (torch.Tensor): Text prompt embeddings
        negative_prompt_embedding (torch.Tensor): Negative prompt embeddings
        height (int): Output video height
        width (int): Output video width
        fps (int): Output video frame rate
        num_video_frames (int): Number of frames to generate

    Returns:
        tuple:
            - data_batch (dict): Complete model input batch
            - state_shape (list): Shape of latent state [C,T,H,W] accounting for VAE compression
    """
    raw_video_batch = prepare_data_batch(
        height=height,
        width=width,
        num_frames=num_video_frames,
        fps=fps,
        prompt_embedding=prompt_embedding,
        negative_prompt_embedding=negative_prompt_embedding,
    )
    state_shape = [
        model.tokenizer.channel,
        model.tokenizer.get_latent_num_frames(num_video_frames),
        height // model.tokenizer.spatial_compression_factor,
        width // model.tokenizer.spatial_compression_factor,
    ]
    return raw_video_batch, state_shape


def get_video_batch_for_multiview_model(
    model, prompt_embedding, height, width, fps, num_video_frames, frame_repeat_negative_condition
):
    """Prepare complete input batch for video generation including latent dimensions.

    Args:
        model: Diffusion model instance
        prompt_embedding (torch.Tensor): Text prompt embeddings
        height (int): Output video height
        width (int): Output video width
        fps (int): Output video frame rate
        num_video_frames (int): Number of frames to generate
        frame_repeat_negative_condition (int): Number of frames to generate

    Returns:
        tuple:
            - data_batch (dict): Complete model input batch
            - state_shape (list): Shape of latent state [C,T,H,W] accounting for VAE compression
    """
    n_views = len(prompt_embedding)
    prompt_embedding = einops.rearrange(torch.cat(prompt_embedding), "n t d -> (n t) d").unsqueeze(0)
    raw_video_batch = prepare_data_batch(
        height=height,
        width=width,
        num_frames=num_video_frames,
        fps=fps,
        prompt_embedding=prompt_embedding,
    )
    if frame_repeat_negative_condition != -1:
        frame_repeat = torch.zeros(n_views)
        frame_repeat[-1] = frame_repeat_negative_condition
        frame_repeat[-2] = frame_repeat_negative_condition
        raw_video_batch["frame_repeat"] = frame_repeat.unsqueeze(0).to(dtype=torch.bfloat16).cuda()
    state_shape = [
        model.tokenizer.channel,
        model.tokenizer.get_latent_num_frames(int(num_video_frames / n_views)) * n_views,
        height // model.tokenizer.spatial_compression_factor,
        width // model.tokenizer.spatial_compression_factor,
    ]
    return raw_video_batch, state_shape


def generate_world_from_text(
    model: DiffusionT2WModel,
    state_shape: list[int],
    is_negative_prompt: bool,
    data_batch: dict,
    guidance: float,
    num_steps: int,
    seed: int,
):
    """Generate video from text prompt using diffusion model.

    Args:
        model (DiffusionT2WModel): Text-to-video diffusion model
        state_shape (list[int]): Latent state dimensions [C,T,H,W]
        is_negative_prompt (bool): Whether negative prompt is provided
        data_batch (dict): Model input batch with embeddings
        guidance (float): Classifier-free guidance scale
        num_steps (int): Number of diffusion sampling steps
        seed (int): Random seed for reproducibility

    Returns:
        np.ndarray: Generated video frames [T,H,W,C], range [0,255]

    The function:
    1. Initializes random latent with maximum noise
    2. Performs guided diffusion sampling
    3. Decodes latents to pixel space
    """

    # Generate video
    sample = model.generate_samples_from_batch(
        data_batch,
        guidance=guidance,
        state_shape=state_shape,
        num_steps=num_steps,
        is_negative_prompt=is_negative_prompt,
        seed=seed,
    )

    return sample


def generate_world_from_video(
    model: DiffusionV2WModel,
    state_shape: list[int],
    is_negative_prompt: bool,
    data_batch: dict,
    guidance: float,
    num_steps: int,
    seed: int,
    condition_latent: torch.Tensor,
    num_input_frames: int,
) -> Tuple[np.array, list, list]:
    """Generate video using a conditioning video/image input.

    Args:
        model (DiffusionV2WModel): The diffusion model instance
        state_shape (list[int]): Shape of the latent state [C,T,H,W]
        is_negative_prompt (bool): Whether negative prompt is provided
        data_batch (dict): Batch containing model inputs including text embeddings
        guidance (float): Classifier-free guidance scale for sampling
        num_steps (int): Number of diffusion sampling steps
        seed (int): Random seed for generation
        condition_latent (torch.Tensor): Latent tensor from conditioning video/image file
        num_input_frames (int): Number of input frames

    Returns:
        np.array: Generated video frames in shape [T,H,W,C], range [0,255]
    """
    assert not model.config.conditioner.video_cond_bool.sample_tokens_start_from_p_or_i, "not supported"
    augment_sigma = DEFAULT_AUGMENT_SIGMA

    if condition_latent.shape[2] < state_shape[1]:
        # Padding condition latent to state shape
        b, c, t, h, w = condition_latent.shape
        condition_latent = torch.cat(
            [
                condition_latent,
                condition_latent.new_zeros(b, c, state_shape[1] - t, h, w),
            ],
            dim=2,
        ).contiguous()
    num_of_latent_condition = compute_num_latent_frames(model, num_input_frames)

    sample = model.generate_samples_from_batch(
        data_batch,
        guidance=guidance,
        state_shape=state_shape,
        num_steps=num_steps,
        is_negative_prompt=is_negative_prompt,
        seed=seed,
        condition_latent=condition_latent,
        num_condition_t=num_of_latent_condition,
        condition_augment_sigma=augment_sigma,
    )
    return sample


def read_video_or_image_into_frames_BCTHW(
    input_path: str,
    input_path_format: str = "mp4",
    H: int = None,
    W: int = None,
    normalize: bool = True,
    max_frames: int = -1,
    also_return_fps: bool = False,
) -> torch.Tensor:
    """Read video or image file and convert to tensor format.

    Args:
        input_path (str): Path to input video/image file
        input_path_format (str): Format of input file (default: "mp4")
        H (int, optional): Height to resize frames to
        W (int, optional): Width to resize frames to
        normalize (bool): Whether to normalize pixel values to [-1,1] (default: True)
        max_frames (int): Maximum number of frames to read (-1 for all frames)
        also_return_fps (bool): Whether to return fps along with frames

    Returns:
        torch.Tensor | tuple: Video tensor in shape [B,C,T,H,W], optionally with fps if requested
    """
    log.debug(f"Reading video from {input_path}")

    loaded_data = load_from_fileobj(input_path, format=input_path_format)
    frames, meta_data = loaded_data
    if input_path.endswith(".png") or input_path.endswith(".jpg") or input_path.endswith(".jpeg"):
        frames = np.array(frames[0])  # HWC, [0,255]
        if frames.shape[-1] > 3:  # RGBA, set the transparent to white
            # Separate the RGB and Alpha channels
            rgb_channels = frames[..., :3]
            alpha_channel = frames[..., 3] / 255.0  # Normalize alpha channel to [0, 1]

            # Create a white background
            white_bg = np.ones_like(rgb_channels) * 255  # White background in RGB

            # Blend the RGB channels with the white background based on the alpha channel
            frames = (rgb_channels * alpha_channel[..., None] + white_bg * (1 - alpha_channel[..., None])).astype(
                np.uint8
            )
        frames = [frames]
        fps = 0
    else:
        fps = int(meta_data.get("fps"))
    if max_frames != -1:
        frames = frames[:max_frames]
    input_tensor = np.stack(frames, axis=0)
    input_tensor = einops.rearrange(input_tensor, "t h w c -> t c h w")
    if normalize:
        input_tensor = input_tensor / 128.0 - 1.0
        input_tensor = torch.from_numpy(input_tensor).bfloat16()  # TCHW
        log.debug(f"Raw data shape: {input_tensor.shape}")
        if H is not None and W is not None:
            input_tensor = transforms_F.resize(
                input_tensor,
                size=(H, W),  # type: ignore
                interpolation=transforms_F.InterpolationMode.BICUBIC,
                antialias=True,
            )
    input_tensor = einops.rearrange(input_tensor, "(b t) c h w -> b c t h w", b=1)
    if normalize:
        input_tensor = input_tensor.to("cuda")
    log.debug(f"Load shape {input_tensor.shape} value {input_tensor.min()}, {input_tensor.max()}")
    if also_return_fps:
        return input_tensor, fps
    return input_tensor


def compute_num_latent_frames(model: DiffusionV2WModel, num_input_frames: int, downsample_factor=8) -> int:
    """This function computes the number of latent frames given the number of input frames.
    Args:
        model (DiffusionV2WModel): video generation model
        num_input_frames (int): number of input frames
        downsample_factor (int): downsample factor for temporal reduce
    Returns:
        int: number of latent frames
    """
    num_latent_frames = (
        num_input_frames
        // model.tokenizer.video_vae.pixel_chunk_duration
        * model.tokenizer.video_vae.latent_chunk_duration
    )
    if num_input_frames % model.tokenizer.video_vae.latent_chunk_duration == 1:
        num_latent_frames += 1
    elif num_input_frames % model.tokenizer.video_vae.latent_chunk_duration > 1:
        assert (
            num_input_frames % model.tokenizer.video_vae.pixel_chunk_duration - 1
        ) % downsample_factor == 0, f"num_input_frames % model.tokenizer.video_vae.pixel_chunk_duration - 1 must be divisible by {downsample_factor}"
        num_latent_frames += (
            1 + (num_input_frames % model.tokenizer.video_vae.pixel_chunk_duration - 1) // downsample_factor
        )

    return num_latent_frames


def create_condition_latent_from_input_frames(
    model: DiffusionV2WModel,
    input_frames: torch.Tensor,
    num_frames_condition: int = 25,
):
    """Create condition latent for video generation from input frames.

    Takes the last num_frames_condition frames from input as conditioning.

    Args:
        model (DiffusionV2WModel): Video generation model
        input_frames (torch.Tensor): Input video tensor [B,C,T,H,W], range [-1,1]
        num_frames_condition (int): Number of frames to use for conditioning

    Returns:
        tuple: (condition_latent, encode_input_frames) where:
            - condition_latent (torch.Tensor): Encoded latent condition [B,C,T,H,W]
            - encode_input_frames (torch.Tensor): Padded input frames used for encoding
    """
    B, C, T, H, W = input_frames.shape
    num_frames_encode = (
        model.tokenizer.pixel_chunk_duration
    )  # (model.state_shape[1] - 1) / model.vae.pixel_chunk_duration + 1
    log.debug(
        f"num_frames_encode not set, set it based on pixel chunk duration and model state shape: {num_frames_encode}"
    )

    log.debug(
        f"Create condition latent from input frames {input_frames.shape}, value {input_frames.min()}, {input_frames.max()}, dtype {input_frames.dtype}"
    )

    assert (
        input_frames.shape[2] >= num_frames_condition
    ), f"input_frames not enough for condition, require at least {num_frames_condition}, get {input_frames.shape[2]}, {input_frames.shape}"
    assert (
        num_frames_encode >= num_frames_condition
    ), f"num_frames_encode should be larger than num_frames_condition, get {num_frames_encode}, {num_frames_condition}"

    # Put the conditioal frames to the begining of the video, and pad the end with zero
    condition_frames = input_frames[:, :, -num_frames_condition:]
    padding_frames = condition_frames.new_zeros(B, C, num_frames_encode - num_frames_condition, H, W)
    encode_input_frames = torch.cat([condition_frames, padding_frames], dim=2)

    log.debug(
        f"create latent with input shape {encode_input_frames.shape} including padding {num_frames_encode - num_frames_condition} at the end"
    )
    if hasattr(model, "n_views"):
        encode_input_frames = einops.rearrange(encode_input_frames, "(B V) C T H W -> B C (V T) H W", V=model.n_views)
    latent = model.encode(encode_input_frames)
    return latent, encode_input_frames


def get_condition_latent(
    model: DiffusionV2WModel,
    input_image_or_video_path: str,
    num_input_frames: int = 1,
    state_shape: list[int] = None,
):
    """Get condition latent from input image/video file.

    Args:
        model (DiffusionV2WModel): Video generation model
        input_image_or_video_path (str): Path to conditioning image/video
        num_input_frames (int): Number of input frames for video2world prediction

    Returns:
        tuple: (condition_latent, input_frames) where:
            - condition_latent (torch.Tensor): Encoded latent condition [B,C,T,H,W]
            - input_frames (torch.Tensor): Input frames tensor [B,C,T,H,W]
    """
    if state_shape is None:
        state_shape = model.state_shape
    assert num_input_frames > 0, "num_input_frames must be greater than 0"

    H, W = (
        state_shape[-2] * model.tokenizer.spatial_compression_factor,
        state_shape[-1] * model.tokenizer.spatial_compression_factor,
    )

    input_path_format = input_image_or_video_path.split(".")[-1]
    input_frames = read_video_or_image_into_frames_BCTHW(
        input_image_or_video_path,
        input_path_format=input_path_format,
        H=H,
        W=W,
    )

    condition_latent, _ = create_condition_latent_from_input_frames(model, input_frames, num_input_frames)
    condition_latent = condition_latent.to(torch.bfloat16)

    return condition_latent


def get_condition_latent_multiview(
    model: DiffusionMultiviewV2WModel,
    input_image_or_video_path: str,
    num_input_frames: int = 1,
    state_shape: list[int] = None,
):
    """Get condition latent from input image/video file. This is the function for the multi-view model where each view has one latent condition frame.

    Args:
        model (DiffusionMultiviewV2WModel): Video generation model
        input_image_or_video_path (str): Path to conditioning image/video
        num_input_frames (int): Number of input frames for video2world prediction

    Returns:
        tuple: (condition_latent, input_frames) where:
            - condition_latent (torch.Tensor): Encoded latent condition [B,C,T,H,W]
            - input_frames (torch.Tensor): Input frames tensor [B,C,T,H,W]
    """
    if state_shape is None:
        state_shape = model.state_shape
    assert num_input_frames > 0, "num_input_frames must be greater than 0"

    H, W = (
        state_shape[-2] * model.tokenizer.spatial_compression_factor,
        state_shape[-1] * model.tokenizer.spatial_compression_factor,
    )
    input_path_format = input_image_or_video_path.split(".")[-1]
    input_frames = read_video_or_image_into_frames_BCTHW(
        input_image_or_video_path,
        input_path_format=input_path_format,
        H=H,
        W=W,
    )
    input_frames = einops.rearrange(input_frames, "B C (V T) H W -> (B V) C T H W", V=model.n_views)
    condition_latent, _ = create_condition_latent_from_input_frames(model, input_frames, num_input_frames)
    condition_latent = condition_latent.to(torch.bfloat16)

    return condition_latent, einops.rearrange(input_frames, "(B V) C T H W -> B C (V T) H W", V=model.n_views)[0]


def check_input_frames(input_path: str, required_frames: int) -> bool:
    """Check if input video/image has sufficient frames.

    Args:
        input_path: Path to input video or image
        required_frames: Number of required frames

    Returns:
        np.ndarray of frames if valid, None if invalid
    """
    if input_path.endswith((".jpg", ".jpeg", ".png")):
        if required_frames > 1:
            log.error(f"Input ({input_path}) is an image but {required_frames} frames are required")
            return False
        return True  # Let the pipeline handle image loading
    # For video input
    try:
        vid = imageio.get_reader(input_path, "ffmpeg")
        frame_count = vid.count_frames()

        if frame_count < required_frames:
            log.error(f"Input video has {frame_count} frames but {required_frames} frames are required")
            return False
        else:
            return True
    except Exception as e:
        log.error(f"Error reading video file {input_path}: {e}")
        return False
