import { toast } from '@blocksuite/affine-components/toast';
import {
  type AttachmentBlockModel,
  type AttachmentBlockProps,
  AttachmentBlockSchema,
} from '@blocksuite/affine-model';
import {
  EMBED_CARD_HEIGHT,
  EMBED_CARD_WIDTH,
} from '@blocksuite/affine-shared/consts';
import {
  type AttachmentUploadedEvent,
  FileSizeLimitProvider,
  TelemetryProvider,
} from '@blocksuite/affine-shared/services';
import { humanFileSize } from '@blocksuite/affine-shared/utils';
import { Bound, type IVec, Vec } from '@blocksuite/global/gfx';
import type { BlockStdScope } from '@blocksuite/std';
import { GfxControllerIdentifier } from '@blocksuite/std/gfx';
import type { BlockModel } from '@blocksuite/store';

import type { AttachmentBlockComponent } from './attachment-block';

export async function getAttachmentBlob(model: AttachmentBlockModel) {
  const { sourceId$, type$ } = model.props;
  const sourceId = sourceId$.peek();
  const type = type$.peek();
  if (!sourceId) return null;

  const doc = model.doc;
  const blob = await doc.blobSync.get(sourceId);
  if (!blob) return null;

  return new Blob([blob], { type });
}

/**
 * Since the size of the attachment may be very large,
 * the download process may take a long time!
 */
export function downloadAttachmentBlob(block: AttachmentBlockComponent) {
  const { host, model, blobUrl, resourceController } = block;

  if (resourceController.state$.peek().downloading) {
    toast(host, 'Download in progress...');
    return;
  }

  const name = model.props.name;
  const shortName = name.length < 20 ? name : name.slice(0, 20) + '...';

  if (!blobUrl) {
    toast(host, `Failed to download ${shortName}!`);
    return;
  }

  resourceController.updateState({ downloading: true });

  toast(host, `Downloading ${shortName}`);

  const tmpLink = document.createElement('a');
  const event = new MouseEvent('click');
  tmpLink.download = name;
  tmpLink.href = blobUrl;
  tmpLink.dispatchEvent(event);
  tmpLink.remove();

  resourceController.updateState({ downloading: false });
}

export async function refreshData(block: AttachmentBlockComponent) {
  const model = block.model;
  const type = model.props.type$.peek();

  await block.resourceController.refreshUrlWith(type);
}

export async function getFileType(file: File) {
  if (file.type) return file.type;

  // If the file type is not available, try to get it from the buffer.
  const buffer = await file.arrayBuffer();
  const FileType = await import('file-type');
  const fileType = await FileType.fileTypeFromBuffer(buffer);
  return fileType?.mime ?? '';
}

function hasExceeded(
  std: BlockStdScope,
  files: File[],
  maxFileSize = std.get(FileSizeLimitProvider).maxFileSize
) {
  const exceeded = files.some(file => file.size > maxFileSize);

  if (exceeded) {
    const size = humanFileSize(maxFileSize, true, 0);
    toast(std.host, `You can only upload files less than ${size}`);
  }

  return exceeded;
}

async function buildPropsWith(
  std: BlockStdScope,
  file: File,
  embed?: boolean,
  mode: 'doc' | 'whiteboard' = 'doc'
) {
  let type = file.type;
  let category: AttachmentUploadedEvent['category'] = 'success';

  try {
    const { name, size } = file;
    // TODO(@fundon): should re-upload when upload timeout
    const sourceId = await std.store.blobSync.set(file);
    type = await getFileType(file);

    return {
      name,
      size,
      type,
      sourceId,
      embed,
    } satisfies Partial<AttachmentBlockProps>;
  } catch (err) {
    category = 'failure';
    throw err;
  } finally {
    // TODO(@fundon): should change event name because this is just a local operation.
    std.getOptional(TelemetryProvider)?.track('AttachmentUploadedEvent', {
      page: `${mode} editor`,
      module: 'attachment',
      segment: 'attachment',
      control: 'uploader',
      type,
      category,
    });
  }
}

/**
 * Add a new attachment block before / after the specified block.
 */
export async function addSiblingAttachmentBlocks(
  std: BlockStdScope,
  files: File[],
  targetModel: BlockModel,
  placement: 'before' | 'after' = 'after',
  embed?: boolean
) {
  if (!files.length) return [];

  if (hasExceeded(std, files)) return [];

  const flavour = AttachmentBlockSchema.model.flavour;

  const propsArray = await Promise.all(
    files.map(file => buildPropsWith(std, file, embed))
  );

  const blockIds = std.store.addSiblingBlocks(
    targetModel,
    propsArray.map(props => ({ ...props, flavour })),
    placement
  );

  return blockIds;
}

export async function addAttachments(
  std: BlockStdScope,
  files: File[],
  point?: IVec,
  shouldTransformPoint?: boolean // determines whether we should use `toModelCoord` to convert the point
): Promise<string[]> {
  if (!files.length) return [];

  if (hasExceeded(std, files)) return [];

  const propsArray = await Promise.all(
    files.map(file => buildPropsWith(std, file, undefined, 'whiteboard'))
  );

  const gfx = std.get(GfxControllerIdentifier);
  let { x, y } = gfx.viewport.center;
  if (point) {
    shouldTransformPoint = shouldTransformPoint ?? true;
    if (shouldTransformPoint) {
      [x, y] = gfx.viewport.toModelCoord(...point);
    } else {
      [x, y] = point;
    }
  }

  const xy = [x, y];
  const style = 'cubeThick';
  const gap = 32;
  const width = EMBED_CARD_WIDTH.cubeThick;
  const height = EMBED_CARD_HEIGHT.cubeThick;
  const flavour = AttachmentBlockSchema.model.flavour;

  const blocks = propsArray.map((props, index) => {
    const center = Vec.addScalar(xy, index * gap);
    const xywh = Bound.fromCenter(center, width, height).serialize();
    return { flavour, blockProps: { ...props, style, xywh } };
  });

  const blockIds = std.store.addBlocks(blocks, gfx.surface);

  gfx.selection.set({
    elements: blockIds,
    editing: false,
  });

  return blockIds;
}