// Copyright 2020 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only

import type Quill from '@signalapp/quill-cjs';
import { Delta } from '@signalapp/quill-cjs';
import { deleteRange } from '@signalapp/quill-cjs/modules/keyboard.js';

import {
  FormattingMenu,
  QuillFormattingStyle,
} from '../formatting/menu.dom.js';
import { insertEmojiOps } from '../util.dom.js';
import { createEventHandler } from './util.dom.js';

type ClipboardOptions = Readonly<{
  isDisabled: boolean;
}>;

export class SignalClipboard {
  quill: Quill;
  options: ClipboardOptions;

  constructor(quill: Quill, options: ClipboardOptions) {
    this.quill = quill;
    this.options = options;

    this.quill.root.addEventListener('paste', e => this.onCapturePaste(e));
    this.quill.root.addEventListener('cut', e => this.onCaptureCut(e));
  }

  updateOptions(options: Partial<ClipboardOptions>): void {
    this.options = { ...this.options, ...options };
  }

  onCaptureCut(event: ClipboardEvent): void {
    const [range] = this.quill.selection.getRange();

    // This updates the clipboard with what we want
    const handler = createEventHandler({ deleteSelection: false });
    handler(event);

    // And this updates quill's internal state and the content-editable to reflect the cut
    if (range) {
      deleteRange({ range, quill: this.quill });
    }
  }

  onCapturePaste(event: ClipboardEvent): void {
    if (this.options.isDisabled) {
      return;
    }

    if (event.clipboardData == null) {
      event.preventDefault();
      event.stopPropagation();

      return;
    }

    const { clipboard } = this.quill;
    const selection = this.quill.getSelection();
    const text = event.clipboardData.getData('text/plain');
    const signal = event.clipboardData.getData('text/signal');

    const clipboardContainsFiles = event.clipboardData.files?.length > 0;

    if (clipboardContainsFiles) {
      return;
    }

    event.preventDefault();
    event.stopPropagation();

    if (selection == null) {
      return;
    }

    if (!text && !signal) {
      return;
    }

    const { ops } = this.quill.getContents(selection.index, selection.length);

    // Check if we're selecting all content
    const totalLength = this.quill.getLength();
    const isSelectingAll = selection.length >= totalLength - 1;

    let formats: Record<string, unknown>;
    if (selection.length === 0) {
      formats = this.quill.getFormat(selection.index);
    } else if (isSelectingAll) {
      // No formatting for select-all
      formats = {};
    } else {
      formats = {
        [QuillFormattingStyle.bold]: FormattingMenu.isStyleEnabledForOps(
          ops,
          QuillFormattingStyle.bold
        ),
        [QuillFormattingStyle.italic]: FormattingMenu.isStyleEnabledForOps(
          ops,
          QuillFormattingStyle.italic
        ),
        [QuillFormattingStyle.monospace]: FormattingMenu.isStyleEnabledForOps(
          ops,
          QuillFormattingStyle.monospace
        ),
        [QuillFormattingStyle.spoiler]: FormattingMenu.isStyleEnabledForOps(
          ops,
          QuillFormattingStyle.spoiler
        ),
        [QuillFormattingStyle.strike]: FormattingMenu.isStyleEnabledForOps(
          ops,
          QuillFormattingStyle.strike
        ),
      };
    }
    const clipboardDelta = signal
      ? clipboard.convert({ html: signal }, formats)
      : new Delta(insertEmojiOps(clipboard.convert({ text }, formats).ops, {}));

    this.quill.selection.update('silent');

    if (selection) {
      setTimeout(() => {
        const delta = new Delta()
          .retain(selection.index)
          .delete(selection.length)
          .concat(clipboardDelta);
        this.quill.updateContents(delta, 'user');
        this.quill.setSelection(delta.length() - selection.length, 0, 'silent');
        this.quill.scrollSelectionIntoView();

        this.quill.focus();
      }, 1);
    }
  }
}
