“use strict”;

var util = _interopRequireWildcard(require(“./util”));

function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) { var desc = Object.defineProperty && Object.getOwnPropertyDescriptor ? Object.getOwnPropertyDescriptor(obj, key) : {}; if (desc.get || desc.set) { Object.defineProperty(newObj, key, desc); } else { newObj = obj; } } } } newObj = obj; return newObj; } }

/**

* Copyright (c) 2014-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/

var hasOwn = Object.prototype.hasOwnProperty; // The hoist function takes a FunctionExpression or FunctionDeclaration // and replaces any Declaration nodes in its body with assignments, then // returns a VariableDeclaration containing just the names of the removed // declarations.

exports.hoist = function (funPath) {

var t = util.getTypes();
t.assertFunction(funPath.node);
var vars = {};

function varDeclToExpr(_ref, includeIdentifiers) {
  var vdec = _ref.node,
      scope = _ref.scope;
  t.assertVariableDeclaration(vdec); // TODO assert.equal(vdec.kind, "var");

  var exprs = [];
  vdec.declarations.forEach(function (dec) {
    // Note: We duplicate 'dec.id' here to ensure that the variable declaration IDs don't
    // have the same 'loc' value, since that can make sourcemaps and retainLines behave poorly.
    vars[dec.id.name] = t.identifier(dec.id.name); // Remove the binding, to avoid "duplicate declaration" errors when it will
    // be injected again.

    scope.removeBinding(dec.id.name);

    if (dec.init) {
      exprs.push(t.assignmentExpression("=", dec.id, dec.init));
    } else if (includeIdentifiers) {
      exprs.push(dec.id);
    }
  });
  if (exprs.length === 0) return null;
  if (exprs.length === 1) return exprs[0];
  return t.sequenceExpression(exprs);
}

funPath.get("body").traverse({
  VariableDeclaration: {
    exit: function exit(path) {
      var expr = varDeclToExpr(path, false);

      if (expr === null) {
        path.remove();
      } else {
        // We don't need to traverse this expression any further because
        // there can't be any new declarations inside an expression.
        util.replaceWithOrRemove(path, t.expressionStatement(expr));
      } // Since the original node has been either removed or replaced,
      // avoid traversing it any further.

      path.skip();
    }
  },
  ForStatement: function ForStatement(path) {
    var init = path.get("init");

    if (init.isVariableDeclaration()) {
      util.replaceWithOrRemove(init, varDeclToExpr(init, false));
    }
  },
  ForXStatement: function ForXStatement(path) {
    var left = path.get("left");

    if (left.isVariableDeclaration()) {
      util.replaceWithOrRemove(left, varDeclToExpr(left, true));
    }
  },
  FunctionDeclaration: function FunctionDeclaration(path) {
    var node = path.node;
    vars[node.id.name] = node.id;
    var assignment = t.expressionStatement(t.assignmentExpression("=", t.clone(node.id), t.functionExpression(path.scope.generateUidIdentifierBasedOnNode(node), node.params, node.body, node.generator, node.expression)));

    if (path.parentPath.isBlockStatement()) {
      // Insert the assignment form before the first statement in the
      // enclosing block.
      path.parentPath.unshiftContainer("body", assignment); // Remove the function declaration now that we've inserted the
      // equivalent assignment form at the beginning of the block.

      path.remove();
    } else {
      // If the parent node is not a block statement, then we can just
      // replace the declaration with the equivalent assignment form
      // without worrying about hoisting it.
      util.replaceWithOrRemove(path, assignment);
    } // Remove the binding, to avoid "duplicate declaration" errors when it will
    // be injected again.

    path.scope.removeBinding(node.id.name); // Don't hoist variables out of inner functions.

    path.skip();
  },
  FunctionExpression: function FunctionExpression(path) {
    // Don't descend into nested function expressions.
    path.skip();
  },
  ArrowFunctionExpression: function ArrowFunctionExpression(path) {
    // Don't descend into nested function expressions.
    path.skip();
  }
});
var paramNames = {};
funPath.get("params").forEach(function (paramPath) {
  var param = paramPath.node;

  if (t.isIdentifier(param)) {
    paramNames[param.name] = param;
  } else {// Variables declared by destructuring parameter patterns will be
    // harmlessly re-declared.
  }
});
var declarations = [];
Object.keys(vars).forEach(function (name) {
  if (!hasOwn.call(paramNames, name)) {
    declarations.push(t.variableDeclarator(vars[name], null));
  }
});

if (declarations.length === 0) {
  return null; // Be sure to handle this case!
}

return t.variableDeclaration("var", declarations);

};