“use strict”; const definitions = require(“../../lib/definitions”);

const has = Function.call.bind(Object.prototype.hasOwnProperty);

function joinComparisons(leftArr, right) {

return (
  leftArr.map(JSON.stringify).join(` === ${right} || `) + ` === ${right}`
);

}

function addIsHelper(type, aliasKeys, deprecated) {

const targetType = JSON.stringify(type);
let aliasSource = "";
if (aliasKeys) {
  aliasSource = " || " + joinComparisons(aliasKeys, "nodeType");
}

let placeholderSource = "";
const placeholderTypes = [];
if (
  definitions.PLACEHOLDERS.includes(type) &&
  has(definitions.FLIPPED_ALIAS_KEYS, type)
) {
  placeholderTypes.push(type);
}
if (has(definitions.PLACEHOLDERS_FLIPPED_ALIAS, type)) {
  placeholderTypes.push(...definitions.PLACEHOLDERS_FLIPPED_ALIAS[type]);
}
if (placeholderTypes.length > 0) {
  placeholderSource =
    ' || nodeType === "Placeholder" && (' +
    joinComparisons(placeholderTypes, "node.expectedNode") +
    ")";
}

return `export function is${type}(node: ?Object, opts?: Object): boolean {
  ${deprecated || ""}
  if (!node) return false;

  const nodeType = node.type;
  if (nodeType === ${targetType}${aliasSource}${placeholderSource}) {
    if (typeof opts === "undefined") {
      return true;
    } else {
      return shallowEqual(node, opts);
    }
  }

  return false;
}
`;

}

module.exports = function generateValidators() {

let output = `// @flow

/*

* This file is auto-generated! Do not modify it directly.
* To re-generate run 'make build'
*/

import shallowEqual from “../../utils/shallowEqual”;nn`;

Object.keys(definitions.VISITOR_KEYS).forEach(type => {
  output += addIsHelper(type);
});

Object.keys(definitions.FLIPPED_ALIAS_KEYS).forEach(type => {
  output += addIsHelper(type, definitions.FLIPPED_ALIAS_KEYS[type]);
});

Object.keys(definitions.DEPRECATED_KEYS).forEach(type => {
  const newType = definitions.DEPRECATED_KEYS[type];
  const deprecated = `console.trace("The node type ${type} has been renamed to ${newType}");`;
  output += addIsHelper(type, null, deprecated);
});

return output;

};