/**
 * Copyright (c) 2013-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */
'use strict';

const babylon = require('babylon');
const fs = require('fs');
const through = require('through2');
const traverse = require('babel-traverse').default;
const gs = require('glob-stream');

const evalToString = require('./evalToString');

const paths = require('../../gulpfile').paths;


const babylonOptions = {
  sourceType: 'module',
  // As a parser, babylon has its own options and we can't directly
  // import/require a babel preset. It should be kept **the same** as
  // the `babel-plugin-syntax-*` ones specified in
  // https://github.com/facebook/fbjs/blob/master/babel-preset/configure.js
  plugins: [
    'classProperties',
    'flow',
    'jsx',
    'trailingFunctionCommas',
    'objectRestSpread',
  ],
};

const warnings = new Set();

function transform(file, enc, cb) {
  fs.readFile(file.path, 'utf8', function(err, source) {
    if (err) {
      cb(err);
      return;
    }

    const ast = babylon.parse(source, babylonOptions);
    traverse(ast, {
      CallExpression: {
        exit: function(astPath) {
          if (astPath.get('callee').isIdentifier({name: 'warning'})) {
            const node = astPath.node;

            // warning messages can be concatenated (`+`) at runtime, so here's
            // a trivial partial evaluator that interprets the literal value
            const warningMsgLiteral = evalToString(node.arguments[1]);
            warnings.add(JSON.stringify(warningMsgLiteral));
          }
        },
      },
    });

    cb(null);
  });
}

const sourcePaths = [].concat(
  paths.react.src,
  paths.reactDOM.src,
  paths.reactNative.src,
  paths.reactTestRenderer.src
);

gs(sourcePaths)
  .pipe(through.obj(transform, cb => {
    process.stdout.write(Array.from(warnings).sort().join('\n') + '\n');
    cb();
  }));