import ApiRequest                                                   from '../models/ApiRequest';
import Config                                                       from '../config/Config';
import { StatusCodes }                                              from 'http-status-codes';
import { CustomValidator, ErrorMessage, FieldMessageFactory, Meta } from 'express-validator/src/base';
import { BailOptions, ValidationChain }                             from 'express-validator/src/chain';
import GitlabManager                                                from '../managers/GitlabManager';


declare type DojoMeta = Meta & {
    req: ApiRequest
};

declare type DojoCustomValidator = (input: any, meta: DojoMeta) => any;


class DojoValidators {
    private static _instance: DojoValidators;

    private constructor() { }

    public static get instance(): DojoValidators {
        if ( !DojoValidators._instance ) {
            DojoValidators._instance = new DojoValidators();
        }

        return DojoValidators._instance;
    }

    private toValidatorSchemaOptions(arg: { errorMessage?: FieldMessageFactory | ErrorMessage, negated?: boolean, bail?: boolean | BailOptions, if?: DojoCustomValidator | ValidationChain, options?: DojoCustomValidator }) {
        // This is a hack to make the types work with req arg as ApiRequest instead of Request
        return arg as unknown as { errorMessage?: FieldMessageFactory | ErrorMessage, negated?: boolean, bail?: boolean | BailOptions, if?: CustomValidator | ValidationChain, options?: CustomValidator };
    }

    private getParamValue(req: ApiRequest, path: string): any {
        return 'body' in req && path in req.body ? req.body[path] : req.query[path];
    }

    readonly nullSanitizer = this.toValidatorSchemaOptions({
                                                               options: (value, {
                                                                   req,
                                                                   location,
                                                                   path
                                                               }) => {
                                                                   try {
                                                                       return value == 'null' || value == 'undefined' || value == '' ? null : value;
                                                                   } catch ( e ) {
                                                                       return value;
                                                                   }
                                                               }
                                                           });

    readonly arraySanitizer = this.toValidatorSchemaOptions({
                                                                options: (value, {
                                                                    req,
                                                                    location,
                                                                    path
                                                                }) => {
                                                                    try {
                                                                        return JSON.parse(value);
                                                                    } catch ( e ) {
                                                                        return value;
                                                                    }
                                                                }
                                                            });

    readonly templateUrlValidator = this.toValidatorSchemaOptions({
                                                                      bail        : true,
                                                                      errorMessage: 'Template doesn\'t exist or you don\'t have access to it',
                                                                      options     : (value, {
                                                                          req,
                                                                          location,
                                                                          path
                                                                      }) => {
                                                                          return new Promise((resolve, reject) => {
                                                                              const template = this.getParamValue(req, path);
                                                                              if ( template ) {
                                                                                  GitlabManager.checkTemplateAccess(template, req).then((templateAccess) => {
                                                                                      templateAccess !== StatusCodes.OK ? reject() : resolve(true);
                                                                                  });
                                                                              }
                                                                              resolve(true);
                                                                          });
                                                                      }
                                                                  });

    readonly templateUrlSanitizer = this.toValidatorSchemaOptions({
                                                                      options: (value, {
                                                                          req,
                                                                          location,
                                                                          path
                                                                      }) => {
                                                                          try {
                                                                              const template = this.getParamValue(req, path);
                                                                              if ( template ) {
                                                                                  return `${ Config.gitlab.urls[0].replace(/^([a-z]{3,5}:\/{2})?(.*)/, `$1${ Config.gitlab.account.username }:${ Config.gitlab.account.token }@$2`) }${ template }.git`;
                                                                              } else {
                                                                                  return Config.enonce.default.template;
                                                                              }
                                                                          } catch ( e ) { }

                                                                          return value;
                                                                      }
                                                                  });
}


export default DojoValidators.instance;