import { Injectable } from '@angular/core';
import { HttpConfig } from '../types';
import { map, take, tap } from 'rxjs/operators';
import { MwHttpConfigService } from './config.service';
import { forkJoin, Observable, of } from 'rxjs';
import { UrlPlaceholderModel } from '../models';

@Injectable()
export class MwUrlService {
  private httpConfig?: HttpConfig;
  constructor(private httpConfigService: MwHttpConfigService) {
    this.httpConfigService.getConfig().subscribe((t) => (this.httpConfig = t));
  }

  getBaseUrl(): string | null {
    return this.httpConfig?.baseUrl || null;
  }

  replacePlaceholders(url: string): Observable<string> {
    if (url.startsWith('/')) {
      url = this.getBaseUrl() + url;
    }
    const placeholders = this.getPlaceholders(url);

    if (placeholders.length > 0) {
      const placeholdersArray$ = placeholders.map((t) =>
        t.value.pipe(
          take(1),
          map((value) => ({
            value,
            placeholder: t.name,
          }))
        )
      );
      return forkJoin(placeholdersArray$).pipe(
        map((placeholdersArray) => {
          placeholdersArray.forEach(
            (t) =>
              (url = url.replace(
                new RegExp(`{${t.placeholder}}`, 'g'),
                t.value
              ))
          );
          return url;
        })
      );
    }

    return of(url);
  }

  private getPlaceholders(url: string): UrlPlaceholderModel[] {
    const len = this.httpConfig?.urlPlaceholders?.length || 0;

    if (len > 0) {
      return (
        this.httpConfig?.urlPlaceholders?.filter((t) =>
          new RegExp(`{${t.name}}`, 'g').test(url)
        ) || []
      );
    }
    return [];
  }
}