import { ImmutableNotebook } from "@nteract/commutable";
import Html2Canvas from "html2canvas";
import { Dropdown, IDropdownProps, ITextFieldProps, Stack, Text, TextField } from "office-ui-fabric-react";
import React, { FunctionComponent, useState } from "react";
import { GalleryCardComponent } from "../../Controls/NotebookGallery/Cards/GalleryCardComponent";
import * as FileSystemUtil from "../../Notebook/FileSystemUtil";
import { NotebookUtil } from "../../Notebook/NotebookUtil";
import "./styled.less";

export interface PublishNotebookPaneProps {
  notebookName: string;
  notebookAuthor: string;
  notebookTags: string;
  imageSrc: string;
  notebookDescription: string;
  notebookCreatedDate: string;
  notebookObject: ImmutableNotebook;
  notebookParentDomElement?: HTMLElement;
  onError: (formError: string, formErrorDetail: string, area: string) => void;
  clearFormError: () => void;
  setNotebookName: (newValue: string) => void;
  setNotebookDescription: (newValue: string) => void;
  setNotebookTags: (newValue: string) => void;
  setImageSrc: (newValue: string) => void;
}

enum ImageTypes {
  Url = "URL",
  CustomImage = "Custom Image",
  TakeScreenshot = "Take Screenshot",
  UseFirstDisplayOutput = "Use First Display Output",
}

export const PublishNotebookPaneComponent: FunctionComponent<PublishNotebookPaneProps> = ({
  notebookName,
  notebookTags,
  imageSrc,
  notebookDescription,
  notebookAuthor,
  notebookCreatedDate,
  notebookObject,
  notebookParentDomElement,
  onError,
  clearFormError,
  setNotebookName,
  setNotebookDescription,
  setNotebookTags,
  setImageSrc,
}: PublishNotebookPaneProps) => {
  const [type, setType] = useState<string>(ImageTypes.CustomImage);
  const CARD_WIDTH = 256;
  const cardImageHeight = 144;
  const cardHeightToWidthRatio = cardImageHeight / CARD_WIDTH;

  const maxImageSizeInMib = 1.5;

  const descriptionPara1 =
    "When published, this notebook will appear in the Azure Cosmos DB notebooks public gallery. Make sure you have removed any sensitive data or output before publishing.";

  const descriptionPara2 = `Would you like to publish and share "${FileSystemUtil.stripExtension(
    notebookName,
    "ipynb"
  )}" to the gallery?`;

  const options: ImageTypes[] = [ImageTypes.CustomImage, ImageTypes.Url];
  const thumbnailSelectorProps: IDropdownProps = {
    label: "Cover image",
    defaultSelectedKey: ImageTypes.CustomImage,
    ariaLabel: "Cover image",
    options: options.map((value: string) => ({ text: value, key: value })),
    onChange: async (event, options) => {
      setImageSrc("");
      clearFormError();
      if (options.text === ImageTypes.TakeScreenshot) {
        try {
          await takeScreenshot(notebookParentDomElement, screenshotErrorHandler);
        } catch (error) {
          screenshotErrorHandler(error);
        }
      } else if (options.text === ImageTypes.UseFirstDisplayOutput) {
        try {
          await takeScreenshot(findFirstOutput(), firstOutputErrorHandler);
        } catch (error) {
          firstOutputErrorHandler(error);
        }
      }
      setType(options.text);
    },
  };

  const thumbnailUrlProps: ITextFieldProps = {
    label: "Cover image url",
    ariaLabel: "Cover image url",
    required: true,
    onChange: (event, newValue) => {
      setImageSrc(newValue);
    },
  };

  const screenshotErrorHandler = (error: Error) => {
    const formError = "Failed to take screen shot";
    const formErrorDetail = `${error}`;
    const area = "PublishNotebookPaneComponent/takeScreenshot";
    onError(formError, formErrorDetail, area);
  };

  const firstOutputErrorHandler = (error: Error) => {
    const formError = "Failed to capture first output";
    const formErrorDetail = `${error}`;
    const area = "PublishNotebookPaneComponent/UseFirstOutput";
    onError(formError, formErrorDetail, area);
  };

  if (notebookParentDomElement) {
    options.push(ImageTypes.TakeScreenshot);
    if (notebookObject) {
      options.push(ImageTypes.UseFirstDisplayOutput);
    }
  }

  const imageToBase64 = (file: File, updateImageSrc: (result: string) => void) => {
    const reader = new FileReader();
    reader.readAsDataURL(file);
    reader.onload = () => {
      updateImageSrc(reader.result.toString());
    };

    reader.onerror = (error) => {
      const formError = `Failed to convert ${file.name} to base64 format`;
      const formErrorDetail = `${error}`;
      const area = "PublishNotebookPaneComponent/selectImageFile";
      onError(formError, formErrorDetail, area);
    };
  };

  const takeScreenshot = (target: HTMLElement, onError: (error: Error) => void): void => {
    const updateImageSrcWithScreenshot = (canvasUrl: string): void => {
      setImageSrc(canvasUrl);
    };

    target.scrollIntoView();
    Html2Canvas(target, {
      useCORS: true,
      allowTaint: true,
      scale: 1,
      logging: true,
    })
      .then((canvas) => {
        //redraw canvas to fit Card Cover Image dimensions
        const originalImageData = canvas.toDataURL();
        const requiredHeight = parseInt(canvas.style.width.split("px")[0]) * cardHeightToWidthRatio;
        canvas.height = requiredHeight;
        const context = canvas.getContext("2d");
        const image = new Image();
        image.src = originalImageData;
        image.onload = () => {
          context.drawImage(image, 0, 0);
          updateImageSrcWithScreenshot(canvas.toDataURL());
        };
      })
      .catch((error) => {
        onError(error);
      });
  };

  const renderThumbnailSelectors = (type: string) => {
    switch (type) {
      case ImageTypes.Url:
        return <TextField {...thumbnailUrlProps} />;
      case ImageTypes.CustomImage:
        return (
          <input
            id="selectImageFile"
            type="file"
            accept="image/*"
            onChange={(event) => {
              const file = event.target.files[0];
              if (file.size / 1024 ** 2 > maxImageSizeInMib) {
                event.target.value = "";
                const formError = `Failed to upload ${file.name}`;
                const formErrorDetail = `Image is larger than ${maxImageSizeInMib} MiB. Please Choose a different image.`;
                const area = "PublishNotebookPaneComponent/selectImageFile";

                onError(formError, formErrorDetail, area);
                setImageSrc("");
                return;
              } else {
                clearFormError();
              }
              imageToBase64(file, (result: string) => {
                setImageSrc(result);
              });
            }}
          />
        );
      default:
        return <></>;
    }
  };

  const findFirstOutput = (): HTMLElement => {
    const indexOfFirstCodeCellWithDisplay = NotebookUtil.findFirstCodeCellWithDisplay(notebookObject);
    const cellOutputDomElements = notebookParentDomElement.querySelectorAll<HTMLElement>(".nteract-cell-outputs");
    return cellOutputDomElements[indexOfFirstCodeCellWithDisplay];
  };

  return (
    <div className="publishNotebookPanelContent">
      <Stack className="panelMainContent" tokens={{ childrenGap: 20 }}>
        <Stack.Item>
          <Text>{descriptionPara1}</Text>
        </Stack.Item>

        <Stack.Item>
          <Text>{descriptionPara2}</Text>
        </Stack.Item>

        <Stack.Item>
          <TextField
            label="Name"
            ariaLabel="Name"
            defaultValue={FileSystemUtil.stripExtension(notebookName, "ipynb")}
            required
            onChange={(event, newValue) => {
              const notebookName = newValue + ".ipynb";
              setNotebookName(notebookName);
            }}
          />
        </Stack.Item>

        <Stack.Item>
          <TextField
            label="Description"
            ariaLabel="Description"
            multiline
            rows={3}
            required
            onChange={(event, newValue) => {
              setNotebookDescription(newValue);
            }}
          />
        </Stack.Item>

        <Stack.Item>
          <TextField
            label="Tags"
            ariaLabel="Tags"
            placeholder="Optional tag 1, Optional tag 2"
            onChange={(event, newValue) => {
              setNotebookTags(newValue);
            }}
          />
        </Stack.Item>

        <Stack.Item>
          <Dropdown {...thumbnailSelectorProps} />
        </Stack.Item>

        <Stack.Item>{renderThumbnailSelectors(type)}</Stack.Item>

        <Stack.Item>
          <Text>Preview</Text>
        </Stack.Item>
        <Stack.Item>
          <GalleryCardComponent
            data={{
              id: undefined,
              name: notebookName,
              description: notebookDescription,
              gitSha: undefined,
              tags: notebookTags.split(","),
              author: notebookAuthor,
              thumbnailUrl: imageSrc,
              created: notebookCreatedDate,
              isSample: false,
              downloads: undefined,
              favorites: undefined,
              views: undefined,
              newCellId: undefined,
              policyViolations: undefined,
              pendingScanJobIds: undefined,
            }}
            isFavorite={undefined}
            showDownload={false}
            showDelete={false}
            onClick={() => undefined}
            onTagClick={undefined}
            onFavoriteClick={undefined}
            onUnfavoriteClick={undefined}
            onDownloadClick={undefined}
            onDeleteClick={undefined}
          />
        </Stack.Item>
      </Stack>
    </div>
  );
};