/**
 * @license
 * Copyright 2023 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

import {RenderedWorkspaceComment} from '../comments/rendered_workspace_comment.js';
import {EventType} from '../events/type.js';
import * as eventUtils from '../events/utils.js';
import {getFocusManager} from '../focus_manager.js';
import {ICopyData} from '../interfaces/i_copyable.js';
import {IPaster} from '../interfaces/i_paster.js';
import * as commentSerialiation from '../serialization/workspace_comments.js';
import {Coordinate} from '../utils/coordinate.js';
import {WorkspaceSvg} from '../workspace_svg.js';
import * as registry from './registry.js';

export class WorkspaceCommentPaster
  implements IPaster<WorkspaceCommentCopyData, RenderedWorkspaceComment>
{
  static TYPE = 'workspace-comment';

  paste(
    copyData: WorkspaceCommentCopyData,
    workspace: WorkspaceSvg,
    coordinate?: Coordinate,
  ): RenderedWorkspaceComment | null {
    const state = copyData.commentState;

    if (coordinate) {
      state['x'] = coordinate.x;
      state['y'] = coordinate.y;
    }

    eventUtils.disable();
    let comment;
    try {
      comment = commentSerialiation.append(
        state,
        workspace,
      ) as RenderedWorkspaceComment;
      moveCommentToNotConflict(comment);
    } finally {
      eventUtils.enable();
    }

    if (!comment) return null;

    if (eventUtils.isEnabled()) {
      eventUtils.fire(new (eventUtils.get(EventType.COMMENT_CREATE))(comment));
    }
    getFocusManager().focusNode(comment);
    return comment;
  }
}

function moveCommentToNotConflict(comment: RenderedWorkspaceComment) {
  const workspace = comment.workspace;
  const translateDistance = 30;
  const coord = comment.getRelativeToSurfaceXY();
  const offset = new Coordinate(0, 0);
  // getRelativeToSurfaceXY is really expensive, so we want to cache this.
  const otherCoords = workspace
    .getTopComments(false)
    .filter((otherComment) => otherComment.id !== comment.id)
    .map((c) => c.getRelativeToSurfaceXY());

  while (
    commentOverlapsOtherExactly(Coordinate.sum(coord, offset), otherCoords)
  ) {
    offset.translate(
      workspace.RTL ? -translateDistance : translateDistance,
      translateDistance,
    );
  }

  comment.moveTo(Coordinate.sum(coord, offset));
}

function commentOverlapsOtherExactly(
  coord: Coordinate,
  otherCoords: Coordinate[],
): boolean {
  return otherCoords.some(
    (otherCoord) =>
      Math.abs(otherCoord.x - coord.x) <= 1 &&
      Math.abs(otherCoord.y - coord.y) <= 1,
  );
}

export interface WorkspaceCommentCopyData extends ICopyData {
  commentState: commentSerialiation.State;
}

registry.register(WorkspaceCommentPaster.TYPE, new WorkspaceCommentPaster());