import { ui } from '../ui';
import { createContainer, removeSelection } from './actions';
import type { EditorState } from './state';
import { groupShapes, ungroupShapes } from './vectorart/grouping';

export interface ShortcutActions {
  play(): void;
  stop(): void;
  togglePause(): void;
  /**
   * Copy and paste of what the visible tab edits: keys (#102), objects and graph pieces (#240).
   * False when there is nothing to do, so the key falls through.
   */
  copy(): boolean;
  paste(): boolean;
  /**
   * Delete on a point the visible tab has picked inside the selection (#288) – a corner of a polygon
   * collider or of an outline, a point of a shape or a curve. False while none is, so the key takes
   * the selection itself.
   */
  removePoint(): boolean;
}

/**
 * Global keyboard shortcuts (see the wiki page "Keyboard"). Text fields keep their own key handling;
 * these only run when no focused widget consumed the key. Returns the call that takes them away
 * again – signing out tears the editor down while the page stays up (#177).
 */
export function installShortcuts(state: EditorState, actions: ShortcutActions): () => void {
  return ui().focus.onGlobalKey((event) => {
    const mod = event.ctrlKey || event.metaKey;
    const key = event.key.toLowerCase();
    // The eyedropper's two keys come first (#276): Enter writes its candidate, Escape leaves without.
    if (state.objectPick && !mod && (event.key === 'Enter' || event.key === 'Escape')) {
      state.endObjectPick(event.key === 'Enter' ? 'take' : 'cancel');
      return true;
    }
    if (event.key === 'Escape' && state.mode === 'play') {
      actions.stop();
      return true;
    }
    if (mod && key === 'z') {
      if (event.shiftKey) state.redo();
      else state.undo();
      return true;
    }
    if (mod && key === 'y') {
      state.redo();
      return true;
    }
    if (mod && key === 'c') return actions.copy();
    if (mod && key === 'v') return actions.paste();
    if (mod && key === 'g') {
      const s = state.selection;
      if (s?.kind === 'object') createContainer(state, s.holderId, s.objectIds);
      // On the shapes of a vector drawing it groups them, and with Shift takes the group away (#190).
      else if (s?.kind === 'shape') (event.shiftKey ? ungroupShapes : groupShapes)(state, s.assetId);
      return true;
    }
    if (event.key === 'Delete' || event.key === 'Backspace')
      return actions.removePoint() || removeSelection(state);
    // Ctrl+Enter starts play and then holds/resumes it. A plain letter would be taken away from
    // the game, which owns the keyboard while playing.
    if (mod && event.key === 'Enter') {
      if (state.mode === 'edit') actions.play();
      else actions.togglePause();
      return true;
    }
    return false;
  });
}