// functions.js

var express = require('express'),
    Parse = require('parse/node').Parse;

import PromiseRouter from '../PromiseRouter';

export class FunctionsRouter extends PromiseRouter {
  
  mountRoutes() {
    this.route('POST', '/functions/:functionName', FunctionsRouter.handleCloudFunction);
  }
  
  static createResponseObject(resolve, reject) {
    return {
      success: function(result) {
        resolve({
          response: {
            result: Parse._encode(result)
          }
        });
      },
      error: function(error) {
        reject(new Parse.Error(Parse.Error.SCRIPT_FAILED, error));
      }
    }
  }
  
  static handleCloudFunction(req) {
    if (Parse.Cloud.Functions[req.params.functionName]) {

      var request = {
        params: Object.assign({}, req.body, req.query),
        master: req.auth && req.auth.isMaster,
        user: req.auth && req.auth.user,
        installationId: req.info.installationId
      };

      if (Parse.Cloud.Validators[req.params.functionName]) {
        var result = Parse.Cloud.Validators[req.params.functionName](request);
        if (!result) {
          throw new Parse.Error(Parse.Error.SCRIPT_FAILED, 'Validation failed.');
        }
      }

      return new Promise(function (resolve, reject) {
        var response = FunctionsRouter.createResponseObject(resolve, reject);
        Parse.Cloud.Functions[req.params.functionName](request, response);
      });
    } else {
      throw new Parse.Error(Parse.Error.SCRIPT_FAILED, 'Invalid function.');
    }
  }
}