/**
 * PubScript keyboard map — the shortcuts the writing surface exposes to the
 * user, plus the ProseMirror keymap additions. Kept separate from the editor
 * instance so the command palette and toolbar can render the same bindings.
 *
 * The TipTap/StarterKit keymap (bold/italic/lists/undo/redo) is registered by
 * the extensions themselves; this module documents the PubScript-level
 * shortcuts and provides the heading-cycle helper.
 */
import type { Editor as TipTapEditor } from "@tiptap/core";

import { SCENE_BREAK } from "./schema.js";

export interface ShortcutDef {
  id: string;
  label: string;
  /** Human-readable binding, platform-aware. */
  binding: string;
  /** Execute the shortcut on the given editor. */
  run: (editor: TipTapEditor) => boolean | void;
}

const MOD = typeof navigator !== "undefined" && navigator.platform.toLowerCase().includes("mac")
  ? "⌘"
  : "Ctrl";

/**
 * Cycle the paragraph at the cursor through Heading 3 → Heading 2 → Heading 1
 * → Normal. Used by the writing surface's "cycle heading" shortcut.
 */
export function cycleHeading(editor: TipTapEditor): boolean {
  const { state } = editor;
  const { from } = state.selection;
  const parent = state.doc.resolve(from).parent;

  // Only cycle paragraph / heading blocks.
  if (parent.type.name !== "paragraph" && parent.type.name !== "heading") {
    return false;
  }

  const level = editor.isActive("heading") ? (editor.getAttributes("heading") as { level: number }).level : 0;
  // 0 == paragraph. Cycle paragraph -> H3 -> H2 -> H1 -> paragraph.
  const next = level === 0 ? 3 : level === 3 ? 0 : level - 1;

  if (next === 0) {
    editor.commands.setNode("paragraph");
  } else {
    editor.commands.toggleMark("heading", { level: next });
  }
  return true;
}

/**
 * The documented PubScript shortcuts. The toolbar and command palette render
 * these so the UI and the actual bindings never drift.
 */
export const pubScriptShortcuts: ShortcutDef[] = [
  {
    id: "cycle-heading",
    label: "Cycle heading",
    binding: `${MOD}⇧H`,
    run: (editor) => cycleHeading(editor),
  },
  {
    id: "scene-break",
    label: "Insert scene break",
    binding: `${MOD}⇧⏎`,
    run: (editor) => {
      editor.commands.insertContent({ type: SCENE_BREAK });
      return true;
    },
  },
  {
    id: "bold",
    label: "Bold",
    binding: `${MOD}B`,
    run: (editor) => editor.commands.toggleMark("bold"),
  },
  {
    id: "italic",
    label: "Italic",
    binding: `${MOD}I`,
    run: (editor) => editor.commands.toggleMark("italic"),
  },
  {
    id: "strike",
    label: "Strikethrough",
    binding: `${MOD}S`,
    run: (editor) => editor.commands.toggleMark("strike"),
  },
  {
    id: "undo",
    label: "Undo",
    binding: `${MOD}Z`,
    run: (editor) => editor.commands.undo(),
  },
  {
    id: "redo",
    label: "Redo",
    binding: `${MOD}⇧Z`,
    run: (editor) => editor.commands.redo(),
  },
];