"""gr.File() component"""

from __future__ import annotations

import tempfile
import warnings
from pathlib import Path
from typing import Any, Callable, Literal

import gradio_client.utils as client_utils
from gradio_client import file
from gradio_client.documentation import document

from gradio import processing_utils
from gradio.components.base import Component
from gradio.data_classes import FileData, ListFiles
from gradio.events import Events
from gradio.utils import NamedString


@document()
class File(Component):
    """
    Creates a file component that allows uploading one or more generic files (when used as an input) or displaying generic files or URLs for download (as output).

    Demo: zip_files, zip_to_json
    """

    EVENTS = [Events.change, Events.select, Events.clear, Events.upload]

    def __init__(
        self,
        value: str | list[str] | Callable | None = None,
        *,
        file_count: Literal["single", "multiple", "directory"] = "single",
        file_types: list[str] | None = None,
        type: Literal["filepath", "binary"] = "filepath",
        label: str | None = None,
        every: float | None = None,
        show_label: bool | None = None,
        container: bool = True,
        scale: int | None = None,
        min_width: int = 160,
        height: int | float | None = None,
        interactive: bool | None = None,
        visible: bool = True,
        elem_id: str | None = None,
        elem_classes: list[str] | str | None = None,
        render: bool = True,
    ):
        """
        Parameters:
            value: Default file(s) to display, given as a str file path or URL, or a list of str file paths / URLs. If callable, the function will be called whenever the app loads to set the initial value of the component.
            file_count: if single, allows user to upload one file. If "multiple", user uploads multiple files. If "directory", user uploads all files in selected directory. Return type will be list for each file in case of "multiple" or "directory".
            file_types: List of file extensions or types of files to be uploaded (e.g. ['image', '.json', '.mp4']). "file" allows any file to be uploaded, "image" allows only image files to be uploaded, "audio" allows only audio files to be uploaded, "video" allows only video files to be uploaded, "text" allows only text files to be uploaded.
            type: Type of value to be returned by component. "file" returns a temporary file object with the same base name as the uploaded file, whose full path can be retrieved by file_obj.name, "binary" returns an bytes object.
            label: The label for this component. Appears above the component and is also used as the header if there are a table of examples for this component. If None and used in a `gr.Interface`, the label will be the name of the parameter this component is assigned to.
            every: If `value` is a callable, run the function 'every' number of seconds while the client connection is open. Has no effect otherwise.sed (e.g. to cancel it) via this component's .load_event attribute.
            show_label: if True, will display label.
            container: If True, will place the component in a container - providing some extra padding around the border.
            scale: relative size compared to adjacent Components. For example if Components A and B are in a Row, and A has scale=2, and B has scale=1, A will be twice as wide as B. Should be an integer. scale applies in Rows, and to top-level Components in Blocks where fill_height=True.
            min_width: minimum pixel width, will wrap if not sufficient screen space to satisfy this value. If a certain scale value results in this Component being narrower than min_width, the min_width parameter will be respected first.
            height: The maximum height of the file component, specified in pixels if a number is passed, or in CSS units if a string is passed. If more files are uploaded than can fit in the height, a scrollbar will appear.
            interactive: if True, will allow users to upload a file; if False, can only be used to display files. If not provided, this is inferred based on whether the component is used as an input or output.
            visible: If False, component will be hidden.
            elem_id: An optional string that is assigned as the id of this component in the HTML DOM. Can be used for targeting CSS styles.
            elem_classes: An optional list of strings that are assigned as the classes of this component in the HTML DOM. Can be used for targeting CSS styles.
            render: If False, component will not render be rendered in the Blocks context. Should be used if the intention is to assign event listeners now but render the component later.
        """
        self.file_count = file_count
        if self.file_count in ["multiple", "directory"]:
            self.data_model = ListFiles
        else:
            self.data_model = FileData
        self.file_types = file_types
        if file_types is not None and not isinstance(file_types, list):
            raise ValueError(
                f"Parameter file_types must be a list. Received {file_types.__class__.__name__}"
            )
        valid_types = [
            "filepath",
            "binary",
        ]
        if type not in valid_types:
            raise ValueError(
                f"Invalid value for parameter `type`: {type}. Please choose from one of: {valid_types}"
            )
        if file_count == "directory" and file_types is not None:
            warnings.warn(
                "The `file_types` parameter is ignored when `file_count` is 'directory'."
            )
        super().__init__(
            label=label,
            every=every,
            show_label=show_label,
            container=container,
            scale=scale,
            min_width=min_width,
            interactive=interactive,
            visible=visible,
            elem_id=elem_id,
            elem_classes=elem_classes,
            render=render,
            value=value,
        )
        self.type = type
        self.height = height

    def _process_single_file(self, f: FileData) -> NamedString | bytes:
        file_name = f.path
        if self.type == "filepath":
            file = tempfile.NamedTemporaryFile(delete=False, dir=self.GRADIO_CACHE)
            file.name = file_name
            return NamedString(file_name)
        elif self.type == "binary":
            with open(file_name, "rb") as file_data:
                return file_data.read()
        else:
            raise ValueError(
                "Unknown type: "
                + str(type)
                + ". Please choose from: 'filepath', 'binary'."
            )

    def preprocess(
        self, payload: ListFiles | FileData | None
    ) -> bytes | str | list[bytes] | list[str] | None:
        """
        Parameters:
            payload: File information as a FileData object, or a list of FileData objects.
        Returns:
            Passes the file as a `str` or `bytes` object, or a list of `str` or list of `bytes` objects, depending on `type` and `file_count`.
        """
        if payload is None:
            return None

        if self.file_count == "single":
            if isinstance(payload, ListFiles):
                return self._process_single_file(payload[0])
            return self._process_single_file(payload)
        if isinstance(payload, ListFiles):
            return [self._process_single_file(f) for f in payload]  # type: ignore
        return [self._process_single_file(payload)]  # type: ignore

    def _download_files(self, value: str | list[str]) -> str | list[str]:
        downloaded_files = []
        if isinstance(value, list):
            for file in value:
                if client_utils.is_http_url_like(file):
                    downloaded_file = processing_utils.save_url_to_cache(
                        file, self.GRADIO_CACHE
                    )
                    downloaded_files.append(downloaded_file)
                else:
                    downloaded_files.append(file)
            return downloaded_files
        if client_utils.is_http_url_like(value):
            downloaded_file = processing_utils.save_url_to_cache(
                value, self.GRADIO_CACHE
            )
            return downloaded_file
        else:
            return value

    def postprocess(self, value: str | list[str] | None) -> ListFiles | FileData | None:
        """
        Parameters:
            value: Expects a `str` filepath or URL, or a `list[str]` of filepaths/URLs.
        Returns:
            File information as a FileData object, or a list of FileData objects.
        """
        if value is None:
            return None
        value = self._download_files(value)
        if isinstance(value, list):
            return ListFiles(
                root=[
                    FileData(
                        path=file,
                        orig_name=Path(file).name,
                        size=Path(file).stat().st_size,
                    )
                    for file in value
                ]
            )
        else:
            return FileData(
                path=value,
                orig_name=Path(value).name,
                size=Path(value).stat().st_size,
            )

    def process_example(self, input_data: str | list | None) -> str:
        if input_data is None:
            return ""
        elif isinstance(input_data, list):
            return ", ".join([Path(file).name for file in input_data])
        else:
            return Path(input_data).name

    def example_payload(self) -> Any:
        if self.file_count == "single":
            return file(
                "https://github.com/gradio-app/gradio/raw/main/test/test_files/sample_file.pdf"
            )
        else:
            return [
                file(
                    "https://github.com/gradio-app/gradio/raw/main/test/test_files/sample_file.pdf"
                )
            ]

    def example_value(self) -> Any:
        if self.file_count == "single":
            return "https://github.com/gradio-app/gradio/raw/main/test/test_files/sample_file.pdf"
        else:
            return [
                "https://github.com/gradio-app/gradio/raw/main/test/test_files/sample_file.pdf"
            ]
