const { wrapIn, setBlockType, chainCommands, newlineInCode, toggleMark } = require('prosemirror-commands');
const { selectNextCell, selectPreviousCell } = require('prosemirror-schema-table');
const { wrapInList, splitListItem, liftListItem, sinkListItem } = require('prosemirror-schema-list');
const { undo, redo } = require('prosemirror-history');

const mac = typeof navigator != 'undefined' ? /Mac/.test(navigator.platform) : false;

// :: (Schema, ?Object) → Object
// Inspect the given schema looking for marks and nodes from the
// basic schema, and if found, add key bindings related to them.
// This will add:
//
// * **Mod-b** for toggling [strong](#schema-basic.StrongMark)
// * **Mod-i** for toggling [emphasis](#schema-basic.EmMark)
// * **Mod-`** for toggling [code font](#schema-basic.CodeMark)
// * **Ctrl-Shift-0** for making the current textblock a paragraph
// * **Ctrl-Shift-1** to **Ctrl-Shift-Digit6** for making the current
//   textblock a heading of the corresponding level
// * **Ctrl-Shift-Backslash** to make the current textblock a code block
// * **Ctrl-Shift-8** to wrap the selection in an ordered list
// * **Ctrl-Shift-9** to wrap the selection in a bullet list
// * **Ctrl->** to wrap the selection in a block quote
// * **Enter** to split a non-empty textblock in a list item while at
//   the same time splitting the list item
// * **Mod-Enter** to insert a hard break
// * **Mod-_** to insert a horizontal rule
//
// You can suppress or map these bindings by passing a `mapKeys`
// argument, which maps key names (say `"Mod-B"` to either `false`, to
// remove the binding, or a new key name string.
function buildKeymap(schema, mapKeys) {
  let keys = {}, type;
  function bind(key, cmd) {
    if (mapKeys) {
      const mapped = mapKeys[key];
      if (mapped === false) return;
      if (mapped) key = mapped;
    }
    keys[key] = cmd;
  }

  bind('Mod-z', undo);
  bind('Mod-y', redo);

  if (type = schema.marks.strong)
    bind('Mod-b', toggleMark(type));
  if (type = schema.marks.em)
    bind('Mod-i', toggleMark(type));
  if (type = schema.marks.code)
    bind('Mod-`', toggleMark(type));

  if (type = schema.nodes.bullet_list)
    bind('Shift-Ctrl-8', wrapInList(type));
  if (type = schema.nodes.ordered_list)
    bind('Shift-Ctrl-9', wrapInList(type));
  if (type = schema.nodes.blockquote)
    bind('Ctrl->', wrapIn(type));
  if (type = schema.nodes.hard_break) {
    let br = type, cmd = chainCommands(newlineInCode, (state, onAction) => {
        onAction(state.tr.replaceSelection(br.create()).scrollAction());
        return true;
      });
    bind('Mod-Enter', cmd);
    bind('Shift-Enter', cmd);
    if (mac) bind('Ctrl-Enter', cmd);
  }
  if (type = schema.nodes.list_item) {
    bind('Enter', splitListItem(type));
    bind('Mod-[', liftListItem(type));
    bind('Mod-]', sinkListItem(type));
  }
  if (type = schema.nodes.paragraph)
    bind('Shift-Ctrl-0', setBlockType(type));
  if (type = schema.nodes.code_block)
    bind('Shift-Ctrl-\\', setBlockType(type));
  if (type = schema.nodes.heading)
    for (let i = 1; i <= 6; i++) bind(`Shift-Ctrl-${ i }`, setBlockType(type, { level: i }));
  if (type = schema.nodes.horizontal_rule) {
    const hr = type;
    bind('Mod-_', (state, onAction) => {
      onAction(state.tr.replaceSelection(hr.create()).scrollAction());
      return true;
    });
  }

  if (schema.nodes.table_row) {
    bind('Tab', selectNextCell);
    bind('Shift-Tab', selectPreviousCell);
  }
  return keys;
}
exports.buildKeymap = buildKeymap;