mousedown()

in packages/ketcher-react/src/script/editor/tool/select/select.ts [109:206]

• 88 lines of code
• 26 McCabe index (conditional complexity)

  mousedown(event: PointerEvent) {
    this.isMouseDown = true;
    const rnd = this.editor.render;
    const ctab = rnd.ctab;
    const molecule = ctab.molecule;

    const map = getMapsForClosestItem(
      this.#lassoHelper.fragment || event.altKey,
    );
    const ci = this.editor.findItem(event, map, null);

    const selected = {
      ...(ci?.map === 'atoms' && { atoms: [ci.id] }),
      ...(ci?.map === 'bonds' && { bonds: [ci.id] }),
    };
    const selectedSgroups = ci
      ? getGroupIdsFromItemArrays(molecule, selected)
      : [];
    const newSelected = getNewSelectedItems(this.editor, selectedSgroups);
    if (newSelected.atoms?.length || newSelected.bonds?.length) {
      this.editor.selection(newSelected);
    }
    const currentPosition = CoordinateTransformation.pageToModel(
      event,
      this.editor.render,
    );

    if (!ci) {
      onSelectionStart(event, this.editor, this.#lassoHelper);
      return true;
    }

    if (ci.map === MULTITAIL_ARROW_KEY && ci.ref) {
      this.dragCtx = this.multitailArrowMoveTool.mousedown(
        event,
        ci as MultitailArrowClosestItem,
      );
    } else if (ci.map === 'rxnArrows' && ci.ref) {
      this.dragCtx = this.reactionArrowMoveTool.mousedown(
        event,
        ci as ReactionArrowClosestItem,
      );
    } else {
      this.dragCtx = {
        item: ci,
        xy0: currentPosition,
      };
    }

    if (!ci || (ci.map === 'atoms' && !event.ctrlKey)) {
      atomLongtapEvent(this, rnd);
    }

    let sel = closestToSel(ci);
    const sgroups = ctab.sgroups.get(ci.id);
    const selection = this.editor.selection();
    if (ci.map === 'frags') {
      const frag = ctab.frags.get(ci.id);
      sel = {
        atoms: frag.fragGetAtoms(ctab, ci.id),
        bonds: frag.fragGetBonds(ctab, ci.id),
      };
    } else if (
      (ci.map === 'sgroups' || ci.map === 'functionalGroups') &&
      sgroups
    ) {
      const sgroup = sgroups.item;
      sel = {
        atoms: SGroup.getAtoms(molecule, sgroup),
        bonds: SGroup.getBonds(molecule, sgroup),
      };
    } else if (ci.map === 'rgroups') {
      const rgroup = ctab.rgroups.get(ci.id);
      sel = {
        atoms: rgroup.getAtoms(rnd),
        bonds: rgroup.getBonds(rnd),
      };
    } else if (ci.map === 'sgroupData') {
      if (isSelected(selection, ci)) return true;
    }

    if (event.shiftKey) {
      this.editor.selection(selMerge(sel, selection, true));
    } else {
      this.editor.selection(null);
      this.editor.selection(isSelected(selection, ci) ? selection : sel);
    }

    this.handleMoveCloseToEdgeOfCanvas();

    this.isReadyForCopy = false;
    this.isCopied = false;
    if (isControlKey(event) && this.dragCtx) {
      this.isReadyForCopy = true;
    }

    return true;
  }