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from __future__ import annotations
import io
import logging
from typing import Optional, Union
from comfy.utils import common_upscale
from comfy_api.input_impl import VideoFromFile
from comfy_api.util import VideoContainer, VideoCodec
from comfy_api.input.video_types import VideoInput
from comfy_api.input.basic_types import AudioInput
from comfy_api_nodes.apis.client import (
    ApiClient,
    ApiEndpoint,
    HttpMethod,
    SynchronousOperation,
    UploadRequest,
    UploadResponse,
)
from server import PromptServer


import numpy as np
from PIL import Image
import requests
import torch
import math
import base64
import uuid
from io import BytesIO
import av


def download_url_to_video_output(video_url: str, timeout: int = None) -> VideoFromFile:
    """Downloads a video from a URL and returns a `VIDEO` output.



    Args:

        video_url: The URL of the video to download.



    Returns:

        A Comfy node `VIDEO` output.

    """
    video_io = download_url_to_bytesio(video_url, timeout)
    if video_io is None:
        error_msg = f"Failed to download video from {video_url}"
        logging.error(error_msg)
        raise ValueError(error_msg)
    return VideoFromFile(video_io)


def downscale_image_tensor(image, total_pixels=1536 * 1024) -> torch.Tensor:
    """Downscale input image tensor to roughly the specified total pixels."""
    samples = image.movedim(-1, 1)
    total = int(total_pixels)
    scale_by = math.sqrt(total / (samples.shape[3] * samples.shape[2]))
    if scale_by >= 1:
        return image
    width = round(samples.shape[3] * scale_by)
    height = round(samples.shape[2] * scale_by)

    s = common_upscale(samples, width, height, "lanczos", "disabled")
    s = s.movedim(1, -1)
    return s


def validate_and_cast_response(

    response, timeout: int = None, node_id: Union[str, None] = None

) -> torch.Tensor:
    """Validates and casts a response to a torch.Tensor.



    Args:

        response: The response to validate and cast.

        timeout: Request timeout in seconds. Defaults to None (no timeout).



    Returns:

        A torch.Tensor representing the image (1, H, W, C).



    Raises:

        ValueError: If the response is not valid.

    """
    # validate raw JSON response
    data = response.data
    if not data or len(data) == 0:
        raise ValueError("No images returned from API endpoint")

    # Initialize list to store image tensors
    image_tensors: list[torch.Tensor] = []

    # Process each image in the data array
    for image_data in data:
        image_url = image_data.url
        b64_data = image_data.b64_json

        if not image_url and not b64_data:
            raise ValueError("No image was generated in the response")

        if b64_data:
            img_data = base64.b64decode(b64_data)
            img = Image.open(io.BytesIO(img_data))

        elif image_url:
            if node_id:
                PromptServer.instance.send_progress_text(
                    f"Result URL: {image_url}", node_id
                )
            img_response = requests.get(image_url, timeout=timeout)
            if img_response.status_code != 200:
                raise ValueError("Failed to download the image")
            img = Image.open(io.BytesIO(img_response.content))

        img = img.convert("RGBA")

        # Convert to numpy array, normalize to float32 between 0 and 1
        img_array = np.array(img).astype(np.float32) / 255.0
        img_tensor = torch.from_numpy(img_array)

        # Add to list of tensors
        image_tensors.append(img_tensor)

    return torch.stack(image_tensors, dim=0)


def validate_aspect_ratio(

    aspect_ratio: str,

    minimum_ratio: float,

    maximum_ratio: float,

    minimum_ratio_str: str,

    maximum_ratio_str: str,

) -> float:
    """Validates and casts an aspect ratio string to a float.



    Args:

        aspect_ratio: The aspect ratio string to validate.

        minimum_ratio: The minimum aspect ratio.

        maximum_ratio: The maximum aspect ratio.

        minimum_ratio_str: The minimum aspect ratio string.

        maximum_ratio_str: The maximum aspect ratio string.



    Returns:

        The validated and cast aspect ratio.



    Raises:

        Exception: If the aspect ratio is not valid.

    """
    # get ratio values
    numbers = aspect_ratio.split(":")
    if len(numbers) != 2:
        raise TypeError(
            f"Aspect ratio must be in the format X:Y, such as 16:9, but was {aspect_ratio}."
        )
    try:
        numerator = int(numbers[0])
        denominator = int(numbers[1])
    except ValueError as exc:
        raise TypeError(
            f"Aspect ratio must contain numbers separated by ':', such as 16:9, but was {aspect_ratio}."
        ) from exc
    calculated_ratio = numerator / denominator
    # if not close to minimum and maximum, check bounds
    if not math.isclose(calculated_ratio, minimum_ratio) or not math.isclose(
        calculated_ratio, maximum_ratio
    ):
        if calculated_ratio < minimum_ratio:
            raise TypeError(
                f"Aspect ratio cannot reduce to any less than {minimum_ratio_str} ({minimum_ratio}), but was {aspect_ratio} ({calculated_ratio})."
            )
        elif calculated_ratio > maximum_ratio:
            raise TypeError(
                f"Aspect ratio cannot reduce to any greater than {maximum_ratio_str} ({maximum_ratio}), but was {aspect_ratio} ({calculated_ratio})."
            )
    return aspect_ratio


def mimetype_to_extension(mime_type: str) -> str:
    """Converts a MIME type to a file extension."""
    return mime_type.split("/")[-1].lower()


def download_url_to_bytesio(url: str, timeout: int = None) -> BytesIO:
    """Downloads content from a URL using requests and returns it as BytesIO.



    Args:

        url: The URL to download.

        timeout: Request timeout in seconds. Defaults to None (no timeout).



    Returns:

        BytesIO object containing the downloaded content.

    """
    response = requests.get(url, stream=True, timeout=timeout)
    response.raise_for_status()  # Raises HTTPError for bad responses (4XX or 5XX)
    return BytesIO(response.content)


def bytesio_to_image_tensor(image_bytesio: BytesIO, mode: str = "RGBA") -> torch.Tensor:
    """Converts image data from BytesIO to a torch.Tensor.



    Args:

        image_bytesio: BytesIO object containing the image data.

        mode: The PIL mode to convert the image to (e.g., "RGB", "RGBA").



    Returns:

        A torch.Tensor representing the image (1, H, W, C).



    Raises:

        PIL.UnidentifiedImageError: If the image data cannot be identified.

        ValueError: If the specified mode is invalid.

    """
    image = Image.open(image_bytesio)
    image = image.convert(mode)
    image_array = np.array(image).astype(np.float32) / 255.0
    return torch.from_numpy(image_array).unsqueeze(0)


def download_url_to_image_tensor(url: str, timeout: int = None) -> torch.Tensor:
    """Downloads an image from a URL and returns a [B, H, W, C] tensor."""
    image_bytesio = download_url_to_bytesio(url, timeout)
    return bytesio_to_image_tensor(image_bytesio)

def process_image_response(response: requests.Response) -> torch.Tensor:
    """Uses content from a Response object and converts it to a torch.Tensor"""
    return bytesio_to_image_tensor(BytesIO(response.content))


def _tensor_to_pil(image: torch.Tensor, total_pixels: int = 2048 * 2048) -> Image.Image:
    """Converts a single torch.Tensor image [H, W, C] to a PIL Image, optionally downscaling."""
    if len(image.shape) > 3:
        image = image[0]
    # TODO: remove alpha if not allowed and present
    input_tensor = image.cpu()
    input_tensor = downscale_image_tensor(
        input_tensor.unsqueeze(0), total_pixels=total_pixels
    ).squeeze()
    image_np = (input_tensor.numpy() * 255).astype(np.uint8)
    img = Image.fromarray(image_np)
    return img


def _pil_to_bytesio(img: Image.Image, mime_type: str = "image/png") -> BytesIO:
    """Converts a PIL Image to a BytesIO object."""
    if not mime_type:
        mime_type = "image/png"

    img_byte_arr = io.BytesIO()
    # Derive PIL format from MIME type (e.g., 'image/png' -> 'PNG')
    pil_format = mime_type.split("/")[-1].upper()
    if pil_format == "JPG":
        pil_format = "JPEG"
    img.save(img_byte_arr, format=pil_format)
    img_byte_arr.seek(0)
    return img_byte_arr


def tensor_to_bytesio(

    image: torch.Tensor,

    name: Optional[str] = None,

    total_pixels: int = 2048 * 2048,

    mime_type: str = "image/png",

) -> BytesIO:
    """Converts a torch.Tensor image to a named BytesIO object.



    Args:

        image: Input torch.Tensor image.

        name: Optional filename for the BytesIO object.

        total_pixels: Maximum total pixels for potential downscaling.

        mime_type: Target image MIME type (e.g., 'image/png', 'image/jpeg', 'image/webp', 'video/mp4').



    Returns:

        Named BytesIO object containing the image data.

    """
    if not mime_type:
        mime_type = "image/png"

    pil_image = _tensor_to_pil(image, total_pixels=total_pixels)
    img_binary = _pil_to_bytesio(pil_image, mime_type=mime_type)
    img_binary.name = (
        f"{name if name else uuid.uuid4()}.{mimetype_to_extension(mime_type)}"
    )
    return img_binary


def tensor_to_base64_string(

    image_tensor: torch.Tensor,

    total_pixels: int = 2048 * 2048,

    mime_type: str = "image/png",

) -> str:
    """Convert [B, H, W, C] or [H, W, C] tensor to a base64 string.



    Args:

        image_tensor: Input torch.Tensor image.

        total_pixels: Maximum total pixels for potential downscaling.

        mime_type: Target image MIME type (e.g., 'image/png', 'image/jpeg', 'image/webp', 'video/mp4').



    Returns:

        Base64 encoded string of the image.

    """
    pil_image = _tensor_to_pil(image_tensor, total_pixels=total_pixels)
    img_byte_arr = _pil_to_bytesio(pil_image, mime_type=mime_type)
    img_bytes = img_byte_arr.getvalue()
    # Encode bytes to base64 string
    base64_encoded_string = base64.b64encode(img_bytes).decode("utf-8")
    return base64_encoded_string


def tensor_to_data_uri(

    image_tensor: torch.Tensor,

    total_pixels: int = 2048 * 2048,

    mime_type: str = "image/png",

) -> str:
    """Converts a tensor image to a Data URI string.



    Args:

        image_tensor: Input torch.Tensor image.

        total_pixels: Maximum total pixels for potential downscaling.

        mime_type: Target image MIME type (e.g., 'image/png', 'image/jpeg', 'image/webp').



    Returns:

        Data URI string (e.g., 'data:image/png;base64,...').

    """
    base64_string = tensor_to_base64_string(image_tensor, total_pixels, mime_type)
    return f"data:{mime_type};base64,{base64_string}"


def upload_file_to_comfyapi(

    file_bytes_io: BytesIO,

    filename: str,

    upload_mime_type: str,

    auth_kwargs: Optional[dict[str,str]] = None,

) -> str:
    """

    Uploads a single file to ComfyUI API and returns its download URL.



    Args:

        file_bytes_io: BytesIO object containing the file data.

        filename: The filename of the file.

        upload_mime_type: MIME type of the file.

        auth_kwargs: Optional authentication token(s).



    Returns:

        The download URL for the uploaded file.

    """
    request_object = UploadRequest(file_name=filename, content_type=upload_mime_type)
    operation = SynchronousOperation(
        endpoint=ApiEndpoint(
            path="/customers/storage",
            method=HttpMethod.POST,
            request_model=UploadRequest,
            response_model=UploadResponse,
        ),
        request=request_object,
        auth_kwargs=auth_kwargs,
    )

    response: UploadResponse = operation.execute()
    upload_response = ApiClient.upload_file(
        response.upload_url, file_bytes_io, content_type=upload_mime_type
    )
    upload_response.raise_for_status()

    return response.download_url


def upload_video_to_comfyapi(

    video: VideoInput,

    auth_kwargs: Optional[dict[str,str]] = None,

    container: VideoContainer = VideoContainer.MP4,

    codec: VideoCodec = VideoCodec.H264,

    max_duration: Optional[int] = None,

) -> str:
    """

    Uploads a single video to ComfyUI API and returns its download URL.

    Uses the specified container and codec for saving the video before upload.



    Args:

        video: VideoInput object (Comfy VIDEO type).

        auth_kwargs: Optional authentication token(s).

        container: The video container format to use (default: MP4).

        codec: The video codec to use (default: H264).

        max_duration: Optional maximum duration of the video in seconds. If the video is longer than this, an error will be raised.



    Returns:

        The download URL for the uploaded video file.

    """
    if max_duration is not None:
        try:
            actual_duration = video.duration_seconds
            if actual_duration is not None and actual_duration > max_duration:
                raise ValueError(
                    f"Video duration ({actual_duration:.2f}s) exceeds the maximum allowed ({max_duration}s)."
                )
        except Exception as e:
            logging.error(f"Error getting video duration: {e}")
            raise ValueError(f"Could not verify video duration from source: {e}") from e

    upload_mime_type = f"video/{container.value.lower()}"
    filename = f"uploaded_video.{container.value.lower()}"

    # Convert VideoInput to BytesIO using specified container/codec
    video_bytes_io = io.BytesIO()
    video.save_to(video_bytes_io, format=container, codec=codec)
    video_bytes_io.seek(0)

    return upload_file_to_comfyapi(
        video_bytes_io, filename, upload_mime_type, auth_kwargs
    )


def audio_tensor_to_contiguous_ndarray(waveform: torch.Tensor) -> np.ndarray:
    """

    Prepares audio waveform for av library by converting to a contiguous numpy array.



    Args:

        waveform: a tensor of shape (1, channels, samples) derived from a Comfy `AUDIO` type.



    Returns:

        Contiguous numpy array of the audio waveform. If the audio was batched,

            the first item is taken.

    """
    if waveform.ndim != 3 or waveform.shape[0] != 1:
        raise ValueError("Expected waveform tensor shape (1, channels, samples)")

    # If batch is > 1, take first item
    if waveform.shape[0] > 1:
        waveform = waveform[0]

    # Prepare for av: remove batch dim, move to CPU, make contiguous, convert to numpy array
    audio_data_np = waveform.squeeze(0).cpu().contiguous().numpy()
    if audio_data_np.dtype != np.float32:
        audio_data_np = audio_data_np.astype(np.float32)

    return audio_data_np


def audio_ndarray_to_bytesio(

    audio_data_np: np.ndarray,

    sample_rate: int,

    container_format: str = "mp4",

    codec_name: str = "aac",

) -> BytesIO:
    """

    Encodes a numpy array of audio data into a BytesIO object.

    """
    audio_bytes_io = io.BytesIO()
    with av.open(audio_bytes_io, mode="w", format=container_format) as output_container:
        audio_stream = output_container.add_stream(codec_name, rate=sample_rate)
        frame = av.AudioFrame.from_ndarray(
            audio_data_np,
            format="fltp",
            layout="stereo" if audio_data_np.shape[0] > 1 else "mono",
        )
        frame.sample_rate = sample_rate
        frame.pts = 0

        for packet in audio_stream.encode(frame):
            output_container.mux(packet)

        # Flush stream
        for packet in audio_stream.encode(None):
            output_container.mux(packet)

    audio_bytes_io.seek(0)
    return audio_bytes_io


def upload_audio_to_comfyapi(

    audio: AudioInput,

    auth_kwargs: Optional[dict[str,str]] = None,

    container_format: str = "mp4",

    codec_name: str = "aac",

    mime_type: str = "audio/mp4",

    filename: str = "uploaded_audio.mp4",

) -> str:
    """

    Uploads a single audio input to ComfyUI API and returns its download URL.

    Encodes the raw waveform into the specified format before uploading.



    Args:

        audio: a Comfy `AUDIO` type (contains waveform tensor and sample_rate)

        auth_kwargs: Optional authentication token(s).



    Returns:

        The download URL for the uploaded audio file.

    """
    sample_rate: int = audio["sample_rate"]
    waveform: torch.Tensor = audio["waveform"]
    audio_data_np = audio_tensor_to_contiguous_ndarray(waveform)
    audio_bytes_io = audio_ndarray_to_bytesio(
        audio_data_np, sample_rate, container_format, codec_name
    )

    return upload_file_to_comfyapi(audio_bytes_io, filename, mime_type, auth_kwargs)


def upload_images_to_comfyapi(

    image: torch.Tensor, max_images=8, auth_kwargs: Optional[dict[str,str]] = None, mime_type: Optional[str] = None

) -> list[str]:
    """

    Uploads images to ComfyUI API and returns download URLs.

    To upload multiple images, stack them in the batch dimension first.



    Args:

        image: Input torch.Tensor image.

        max_images: Maximum number of images to upload.

        auth_kwargs: Optional authentication token(s).

        mime_type: Optional MIME type for the image.

    """
    # if batch, try to upload each file if max_images is greater than 0
    idx_image = 0
    download_urls: list[str] = []
    is_batch = len(image.shape) > 3
    batch_length = 1
    if is_batch:
        batch_length = image.shape[0]
    while True:
        curr_image = image
        if len(image.shape) > 3:
            curr_image = image[idx_image]
        # get BytesIO version of image
        img_binary = tensor_to_bytesio(curr_image, mime_type=mime_type)
        # first, request upload/download urls from comfy API
        if not mime_type:
            request_object = UploadRequest(file_name=img_binary.name)
        else:
            request_object = UploadRequest(
                file_name=img_binary.name, content_type=mime_type
            )
        operation = SynchronousOperation(
            endpoint=ApiEndpoint(
                path="/customers/storage",
                method=HttpMethod.POST,
                request_model=UploadRequest,
                response_model=UploadResponse,
            ),
            request=request_object,
            auth_kwargs=auth_kwargs,
        )
        response = operation.execute()

        upload_response = ApiClient.upload_file(
            response.upload_url, img_binary, content_type=mime_type
        )
        # verify success
        try:
            upload_response.raise_for_status()
        except requests.exceptions.HTTPError as e:
            raise ValueError(f"Could not upload one or more images: {e}") from e
        # add download_url to list
        download_urls.append(response.download_url)

        idx_image += 1
        # stop uploading additional files if done
        if is_batch and max_images > 0:
            if idx_image >= max_images:
                break
            if idx_image >= batch_length:
                break
    return download_urls


def resize_mask_to_image(mask: torch.Tensor, image: torch.Tensor,

                         upscale_method="nearest-exact", crop="disabled",

                         allow_gradient=True, add_channel_dim=False):
    """

    Resize mask to be the same dimensions as an image, while maintaining proper format for API calls.

    """
    _, H, W, _ = image.shape
    mask = mask.unsqueeze(-1)
    mask = mask.movedim(-1,1)
    mask = common_upscale(mask, width=W, height=H, upscale_method=upscale_method, crop=crop)
    mask = mask.movedim(1,-1)
    if not add_channel_dim:
        mask = mask.squeeze(-1)
    if not allow_gradient:
        mask = (mask > 0.5).float()
    return mask


def validate_string(string: str, strip_whitespace=True, field_name="prompt", min_length=None, max_length=None):
    if strip_whitespace:
        string = string.strip()
    if min_length and len(string) < min_length:
        raise Exception(f"Field '{field_name}' cannot be shorter than {min_length} characters; was {len(string)} characters long.")
    if max_length and len(string) > max_length:
        raise Exception(f" Field '{field_name} cannot be longer than {max_length} characters; was {len(string)} characters long.")
    if not string:
        raise Exception(f"Field '{field_name}' cannot be empty.")