/*
 * decaffeinate suggestions:
 * DS205: Consider reworking code to avoid use of IIFEs
 * DS207: Consider shorter variations of null checks
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
const _ = require('underscore');

const ItemSpecificities = new WeakMap();

var merge = function(menu, item, itemSpecificity) {
  let matchingItem;
  if (itemSpecificity == null) {
    itemSpecificity = Infinity;
  }
  item = cloneMenuItem(item);
  if (itemSpecificity) {
    ItemSpecificities.set(item, itemSpecificity);
  }
  const matchingItemIndex = findMatchingItemIndex(menu, item);
  if (matchingItemIndex !== -1) {
    matchingItem = menu[matchingItemIndex];
  }

  if (matchingItem != null) {
    if (item.submenu != null) {
      return item.submenu.map(submenuItem =>
        merge(matchingItem.submenu, submenuItem, itemSpecificity)
      );
    } else if (itemSpecificity) {
      if (!(itemSpecificity < ItemSpecificities.get(matchingItem))) {
        return (menu[matchingItemIndex] = item);
      }
    }
  } else if (item.type !== 'separator' || (_.last(menu) || {}).type !== 'separator') {
    return menu.push(item);
  }
};

var unmerge = function(menu, item) {
  let matchingItem;
  const matchingItemIndex = findMatchingItemIndex(menu, item);
  if (matchingItemIndex !== -1) {
    matchingItem = menu[matchingItemIndex];
  }

  if (matchingItem != null) {
    if (item.submenu != null) {
      for (let submenuItem of Array.from(item.submenu)) {
        unmerge(matchingItem.submenu, submenuItem);
      }
    }

    if (
      (matchingItem.submenu != null ? matchingItem.submenu : []).length === 0 ||
      matchingItem.isOptional
    ) {
      return menu.splice(matchingItemIndex, 1);
    }
  }
};

var findMatchingItemIndex = function(menu, { type, label, submenu }) {
  if (type === 'separator') {
    return -1;
  }
  for (let index = 0; index < menu.length; index++) {
    const item = menu[index];
    if (
      normalizeLabel(item.label) === normalizeLabel(label) &&
      (item.submenu != null) === (submenu != null)
    ) {
      return index;
    }
  }
  return -1;
};

var normalizeLabel = function(label) {
  if (label == null) {
    return undefined;
  }

  if (process.platform === 'darwin') {
    return label;
  } else {
    return label.replace(/&/g, '');
  }
};

var cloneMenuItem = function(item) {
  item = Object.assign({}, item);
  if (item.submenu != null) {
    item.submenu = item.submenu.map(submenuItem => cloneMenuItem(submenuItem));
  }
  return item;
};

var forEachMenuItem = (menu, callback) =>
  (() => {
    const result = [];
    for (let item of Array.from(menu)) {
      if (item.submenu != null) {
        forEachMenuItem(item.submenu, callback);
      }
      result.push(callback(item));
    }
    return result;
  })();

module.exports = { merge, unmerge, normalizeLabel, cloneMenuItem, forEachMenuItem };