/********************************************************************************
 * Copyright (c) 2015-2018 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 ********************************************************************************/


import { Injectable } from '@angular/core';
import { Http, Response, Headers, RequestOptions } from '@angular/http';

import { PropertyService } from '../core/property.service';

import { plainToClass } from 'class-transformer';
import { HttpErrorHandler } from '../core/http-error-handler';
import { throwError as observableThrowError,  Observable } from 'rxjs';
import { map, catchError } from 'rxjs/operators';
import { Node } from '../navigator/node';

@Injectable()
export class ExtSystemService {

  private prefEndpoint: string;

  constructor(private http: Http,
              private httpErrorHandler: HttpErrorHandler,
              private _prop: PropertyService) {
    this.prefEndpoint = _prop.getUrl('mdm/administration/');
  }

  getExtSystemForScope(scope: string, key?: string): Observable<Node[]> {
      if (key == null) {
          key = '';
      }

    return this.http.get(this.prefEndpoint + scope + '/externalsystems').pipe(
      map(response => plainToClass(Node, response.json().data)),
          catchError(this.handleError));
  }

  getExtSystemAttributesForScope(scope: string, id: string, key?: string): Observable<Node[]> {
      if (key == null) {
          key = '';
      }

    return this.http.get(this.prefEndpoint + scope + '/externalsystems/attributes/' + id).pipe(
      map(response => plainToClass(Node, response.json().data)),
          catchError(this.handleError));
  }

  getExtSystem(key?: string) {
      if (key == null) {
          key = '';
      }
      return this.http.get(this.prefEndpoint + '?key=' + key).pipe(
        map(response => plainToClass(Node, response.json().data)),
          catchError(this.handleError));
  }

  getAttributeValueFromNode(node: Node, attribute: string) {
    if (node.attributes !== undefined) {
      for (let i in node.attributes) {
        if (node.attributes[i].name === attribute) {
          return node.attributes[i].value;
        }
      }
    }
    return '';
  }

  saveExtSystemAttr(scope: string, extSystemAttr: Node, extSystem: Node) {
    let headers = new Headers({ 'Content-Type': 'application/json' });
    let options = new RequestOptions({ headers: headers });

    let structure = {};
    structure['Name'] = extSystemAttr.name;

    if (parseInt(extSystemAttr.id, 10) > 0) {
      structure['Description'] = this.getAttributeValueFromNode(extSystemAttr, 'Description');
      // update
      return this.http.put(this.prefEndpoint + scope + '/externalsystems/attribute/' + extSystemAttr.id,
        JSON.stringify(structure), options).pipe(
          catchError(this.handleError)
        );
    } else {
      structure['ExtSystemAttribute'] = extSystemAttr;
      // only provide the ID as the backend will evaluate the whole json string
      structure['ExtSystem'] = extSystem.id;
      // create
      return this.http.post(this.prefEndpoint + scope + '/externalsystems/attribute', JSON.stringify(structure), options).pipe(
        catchError(this.handleError));
    }
  }

  saveExtSystemMDMAttr(scope: string, extSystemMDMAttr: Node, extSystemAttr: Node) {
    let headers = new Headers({ 'Content-Type': 'application/json' });
    let options = new RequestOptions({ headers: headers });

    let structure = {};
    structure['Name'] = extSystemMDMAttr.name;

    if (parseInt(extSystemMDMAttr.id, 10) > 0) {
      structure['CompType'] = this.getAttributeValueFromNode(extSystemMDMAttr, 'CompType');
      structure['CompName'] = this.getAttributeValueFromNode(extSystemMDMAttr, 'CompName');
      structure['AttrName'] = this.getAttributeValueFromNode(extSystemMDMAttr, 'AttrName');
      // update
      return this.http.put(this.prefEndpoint + scope + '/externalsystems/mdmattribute/' + extSystemMDMAttr.id,
        JSON.stringify(structure), options).pipe(
          catchError(this.handleError)
        );
    } else {
      structure['MDMAttribute'] = extSystemMDMAttr;
      structure['ExtSystemAttribute'] = extSystemAttr.id;
      // create
      return this.http.post(this.prefEndpoint + scope + '/externalsystems/mdmattribute', JSON.stringify(structure), options).pipe(
        catchError(this.handleError));
    }
  }

  saveExtSystem(scope: string, extSystem: Node) {
    let headers = new Headers({ 'Content-Type': 'application/json' });
    let options = new RequestOptions({ headers: headers });

    let structure = {};
    structure['Name'] = extSystem.name;

    if (parseInt(extSystem.id, 10) > 0) {
      // update
      structure['Description'] = this.getAttributeValueFromNode(extSystem, 'Description');
      return this.http.put(this.prefEndpoint + scope + '/externalsystems/' + extSystem.id, JSON.stringify(structure), options).pipe(
        catchError(this.handleError));
    } else {
      structure['ExtSystem'] = extSystem;
      // create
      return this.http.post(this.prefEndpoint + scope + '/externalsystems', JSON.stringify(structure), options).pipe(
        catchError(this.handleError));
    }
  }

  deleteExtSystem(scope: string, id: string) {
    return this.http.delete(this.prefEndpoint + scope + '/externalsystems/' + id).pipe(
      catchError(this.handleError));
  }
  deleteExtSystemAttr(scope: string, id: string) {
    return this.http.delete(this.prefEndpoint + scope + '/externalsystems/attribute/' + id).pipe(
      catchError(this.handleError));
  }
  deleteExtSystemMDMAttr(scope: string, id: string) {
    return this.http.delete(this.prefEndpoint + scope + '/externalsystems/mdmattribute/' + id).pipe(
      catchError(this.handleError));
  }

  private handleError(e: Error | any) {
    if (e instanceof Response) {
      let response = <Response> e;
      if (response.status !== 200) {
        return observableThrowError('Could not request extSystems! '
          + 'Please check if application server is running and extSystem database is configured correctly.');
      }
    }
    return this.httpErrorHandler.handleError(e);
  }
}