import {IMPLEMENTS, print} from 'angular2/src/facade/lang';
import {UrlResolver} from 'angular2/src/services/url_resolver';
import {isPresent, isBlank, RegExpWrapper, StringWrapper, BaseException} from 'angular2/src/facade/lang';
import {DOM} from 'angular2/src/dom/dom_adapter';
import {Injectable} from 'angular2/di';
import {ReflectionCapabilities} from 'angular2/src/reflection/reflection_capabilities';
import {reflector} from 'angular2/src/reflection/reflection';
import {BrowserDomAdapter} from 'angular2/src/dom/browser_adapter';

export function commonDemoSetup(): void {
  BrowserDomAdapter.makeCurrent();
  reflector.reflectionCapabilities = new ReflectionCapabilities();
}

@Injectable()
@IMPLEMENTS(UrlResolver)
export class DemoUrlResolver {
    static a;

    isInPubServe:boolean;

    constructor() {
        if (isBlank(UrlResolver.a)) {
            UrlResolver.a = DOM.createElement('a');
        }
        this.isInPubServe = _isInPubServe();
    }

    resolve(baseUrl: string, url: string): string {
        if (isBlank(baseUrl)) {
            DOM.resolveAndSetHref(UrlResolver.a, url, null);
            return DOM.getHref(UrlResolver.a);
        }

        if (isBlank(url) || url == '') return baseUrl;

        if (url[0] == '/') {
            throw new BaseException(`Could not resolve the url ${url} from ${baseUrl}`);
        }

        var m = RegExpWrapper.firstMatch(_schemeRe, url);

        if (isPresent(m[1])) {
            return url;
        }

        if (StringWrapper.startsWith(url, './')) {
            return `${baseUrl}/${url}`;
        }

        if (this.isInPubServe) {
            return `/packages/${url}`;
        } else {
            return `/${url}`;
        }
    }
}

var _schemeRe = RegExpWrapper.create('^([^:/?#]+:)?');

// TODO: remove this hack when http://dartbug.com/23128 is fixed
function _isInPubServe():boolean {
  try {
      int.parse('123');
      print('>> Running in Dart');
      return true;
  } catch(_) {
      print('>> Running in JS');
      return false;
  }
}