// http://www.syntaxsuccess.com/viewarticle/lettable-operators-in-rxjs
// https://codecraft.tv/courses/angular/http/http-with-observables/
// https://blog.sstorie.com/onpush-gotcha-when-using-angular-2-form-control/
// https://stackoverflow.com/questions/43074131/primeng-autocomplete-multiple-preselect-value [wrong!!!]
// https://stackoverflow.com/questions/48663965/primeng-autocomplete-component-with-different-colors-for-each-item-normally-th

import { Component, Injectable, OnInit } from '@angular/core';
import { HttpClient, HttpHeaders, HttpErrorResponse } from '@angular/common/http';
import { FormBuilder, FormGroup, FormControl, Validators} from '@angular/forms';
//import { Observable } from 'rxjs/Observable';
//import { Observable, pipe } from 'rxjs/Rx';
import { debounceTime, distinctUntilChanged, filter, map, pluck, switchMap, tap } from 'rxjs/operators';

import { from } from 'rxjs/observable/from';
//import { pluck } from 'rxjs/operators';


const URL = 'https://my-json-server.typicode.com/spham-xyz/cars/cars';

interface car {
  brand: string;
  year: number;
  color: string;
  vin: string;
}

@Component({
  selector: 'my-app',
  templateUrl: 'app/app.template.html'
})
export class AppComponent implements OnInit{
  
  reForm: FormGroup;
  myForm: FormGroup;

  brands = ["VW","Fiat"];
  initialValues = ["VW","Fiat"];
  allBrands: string[];  // ['Audi','BMW','Fiat','Ford','Honda','Jaguar','Mercedes','Renault','Volvo','VW'];
  filteredBrands: string[];
  private searchField: FormControl;
  
  //private brandSelected = new Subject<string>();

  constructor(private http: HttpClient, private fb: FormBuilder) {}

  ngOnInit() {
    this.reForm = new FormGroup({
      //brand: new FormControl(["VW","Fiat"])
      brand: new FormControl([])
    });    
    this.reForm.setValue({brand: this.initialValues});
    
    /*
    this.myForm = new FormGroup({
      name: new FormControl('Benedict'),
      email: new FormControl(''),
      message: new FormControl('')
    });
    */
    this.myForm = this.fb.group({
      name: ['Benedict', Validators.required],
      email: ['', [Validators.required, Validators.pattern('[a-z0-9.@]*')]],
      message: ['', [Validators.required, Validators.minLength(15)]]
    });    

    //this.getCars()
    this.http.get(URL)
        .pipe(
          //tap(data => console.log(data)),

          map(rows => rows.map(function(el,i,arr) {
            return el['brand'];
          })),            
          /* 2nd (LONG) method
          map(rows => {
            var i, rv = [];
            for (i = 0; i < Object.keys(rows).length; ++i) {
              rv[i] = rows[i]['brand'];
            }
            
            return rv;
          }),    
          */

          //filter(data => data.brand == "VW")
          //pluck('brand')
          tap(data => console.log(data))
        )
        .subscribe( 
          (data) => this.allBrands = data,
          (err: HttpErrorResponse) => {
            if (err.error instanceof Error) {
              console.log("Client-side error occured.");
            } else {
              console.log("Server-side error occured.");
            }
          }          
        )
        
    /*
    this.searchField = new FormControl();
    this.searchField.valueChanges
      .debounceTime(400)
      .distinctUntilChanged()
      //.switchMap( term => this.itunes.search(term))
      .subscribe( value => console.log(value));
    */
/*
    const source = from([{ name: 'Joe', age: 30 }, { name: 'Sarah', age: 35 }]);
    //grab names
    const example = source.pipe(pluck('name'));
    //output: "Joe", "Sarah"
    const subscribe = example.subscribe(val => console.log(val));
*/
  }
  
  
  getCars(): Observable<any[]> {
    return this.http.get(URL);
  }

  filterBrands(event) {
    this.filteredBrands = this.allBrands.filter(function(el) {
      var re = new RegExp(`\^${event.query}`, 'gi');
      if( re.test(el) ) return el;
      //if(el.toLowerCase().startsWith(event.query.toLowerCase())) return el;
    })
  }
  
  onSubmit(form: FormGroup) {
    console.log('Valid?', form.valid); // true or false
    console.log('Name: ', form.value.name);
    console.log('Email: ', form.value.email);
    console.log('Message: ', form.value.message);
  }  

}
import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule, ReactiveFormsModule }    from '@angular/forms';
import { HttpClientModule } from '@angular/common/http';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';

import { AppComponent }   from './app.component';

// Import PrimeNG modules
import {AccordionModule} from 'primeng/primeng';
import {AutoCompleteModule} from 'primeng/primeng';
import {BreadcrumbModule} from 'primeng/primeng';
import {ButtonModule} from 'primeng/primeng';
import {CalendarModule} from 'primeng/primeng';
import {CarouselModule} from 'primeng/primeng';
import {ChartModule} from 'primeng/primeng';
import {CheckboxModule} from 'primeng/primeng';
import {ChipsModule} from 'primeng/primeng';
import {CodeHighlighterModule} from 'primeng/primeng';
import {ConfirmDialogModule} from 'primeng/primeng';
import {SharedModule} from 'primeng/primeng';
import {ContextMenuModule} from 'primeng/primeng';
import {DataGridModule} from 'primeng/primeng';
import {DataListModule} from 'primeng/primeng';
import {DataScrollerModule} from 'primeng/primeng';
import {DataTableModule} from 'primeng/primeng';
import {DialogModule} from 'primeng/primeng';
import {DragDropModule} from 'primeng/primeng';
import {DropdownModule} from 'primeng/primeng';
import {EditorModule} from 'primeng/primeng';
import {FieldsetModule} from 'primeng/primeng';
import {FileUploadModule} from 'primeng/primeng';
import {GalleriaModule} from 'primeng/primeng';
import {GMapModule} from 'primeng/primeng';
import {GrowlModule} from 'primeng/primeng';
import {InputMaskModule} from 'primeng/primeng';
import {InputSwitchModule} from 'primeng/primeng';
import {InputTextModule} from 'primeng/primeng';
import {InputTextareaModule} from 'primeng/primeng';
import {LightboxModule} from 'primeng/primeng';
import {ListboxModule} from 'primeng/primeng';
import {MegaMenuModule} from 'primeng/primeng';
import {MenuModule} from 'primeng/primeng';
import {MenubarModule} from 'primeng/primeng';
import {MessagesModule} from 'primeng/primeng';
import {MultiSelectModule} from 'primeng/primeng';
import {OrderListModule} from 'primeng/primeng';
import {OverlayPanelModule} from 'primeng/primeng';
import {PaginatorModule} from 'primeng/primeng';
import {PanelModule} from 'primeng/primeng';
import {PanelMenuModule} from 'primeng/primeng';
import {PasswordModule} from 'primeng/primeng';
import {PickListModule} from 'primeng/primeng';
import {ProgressBarModule} from 'primeng/primeng';
import {RadioButtonModule} from 'primeng/primeng';
import {RatingModule} from 'primeng/primeng';
import {ScheduleModule} from 'primeng/primeng';
import {SelectButtonModule} from 'primeng/primeng';
import {SlideMenuModule} from 'primeng/primeng';
import {SliderModule} from 'primeng/primeng';
import {SpinnerModule} from 'primeng/primeng';
import {SplitButtonModule} from 'primeng/primeng';
import {StepsModule} from 'primeng/primeng';
import {TabMenuModule} from 'primeng/primeng';
import {TabViewModule} from 'primeng/primeng';
import {TerminalModule} from 'primeng/primeng';
import {TieredMenuModule} from 'primeng/primeng';
import {ToggleButtonModule} from 'primeng/primeng';
import {ToolbarModule} from 'primeng/primeng';
import {TooltipModule} from 'primeng/primeng';
import {TreeModule} from 'primeng/primeng';
import {TreeTableModule} from 'primeng/primeng';

@NgModule({
  imports: [ 
        BrowserModule, 
        FormsModule,
        ReactiveFormsModule,
        HttpClientModule,
        BrowserAnimationsModule,
        AccordionModule,
        AutoCompleteModule,
        BreadcrumbModule,
        ButtonModule,
        CalendarModule,
        CarouselModule,
        ChartModule,
        CheckboxModule,
        ChipsModule,
        CodeHighlighterModule,
        ConfirmDialogModule,
        SharedModule,
        ContextMenuModule,
        DataGridModule,
        DataListModule,
        DataScrollerModule,
        DataTableModule,
        DialogModule,
        DragDropModule,
        DropdownModule,
        EditorModule,
        FieldsetModule,
        FileUploadModule,
        GalleriaModule,
        GMapModule,
        GrowlModule,
        InputMaskModule,
        InputSwitchModule,
        InputTextModule,
        InputTextareaModule,
        LightboxModule,
        ListboxModule,
        MegaMenuModule,
        MenuModule,
        MenubarModule,
        MessagesModule,
        MultiSelectModule,
        OrderListModule,
        OverlayPanelModule,
        PaginatorModule,
        PanelModule,
        PanelMenuModule,
        PasswordModule,
        PickListModule,
        ProgressBarModule,
        RadioButtonModule,
        RatingModule,
        ScheduleModule,
        SelectButtonModule,
        SlideMenuModule,
        SliderModule,
        SpinnerModule,
        SplitButtonModule,
        StepsModule,
        TabMenuModule,
        TabViewModule,
        TerminalModule,
        TieredMenuModule,
        ToggleButtonModule,
        ToolbarModule,
        TooltipModule,
        TreeModule,
        TreeTableModule ],
  declarations: [ AppComponent ],
  bootstrap:    [ AppComponent ]
})

export class AppModule { }


/*
Copyright 2016 Google Inc. All Rights Reserved.
Use of this source code is governed by an MIT-style license that
can be found in the LICENSE file at http://angular.io/license
*/
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';

import { AppModule } from './app.module';

const platform = platformBrowserDynamic();
platform.bootstrapModule(AppModule);
body {
  padding: 2em;
  font-family: Arial, Helvetica, sans-serif;
}
<!DOCTYPE html>
<html>
  <head>
    <title>Angular QuickStart</title>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="styles.css">
    
    <!-- PrimeNG style dependencies -->
    <link rel="stylesheet" href="https://unpkg.com/primeng@5.2.4/resources/themes/omega/theme.css" />
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" />
    <link rel="stylesheet" href="https://unpkg.com/primeng@5.2.4/resources/primeng.min.css" />

    <!-- 1. Load libraries -->
    <!-- Polyfill for older browsers -->
    <script src="https://unpkg.com/core-js/client/shim.min.js"></script>

    <script src="https://unpkg.com/zone.js@0.8.4?main=browser"></script>
    <script src="https://unpkg.com/reflect-metadata@0.1.8"></script>
    <script src="https://unpkg.com/systemjs@0.19.39/dist/system.src.js"></script>

    <!-- 2. Configure SystemJS -->
    <script src="systemjs.config.js"></script>
    
  </head>

  <!-- 3. Display the application -->
  <body>
    <my-app>Loading...</my-app>
  </body>
</html>


<!-- 
Copyright 2016 Google Inc. All Rights Reserved.
Use of this source code is governed by an MIT-style license that
can be found in the LICENSE file at http://angular.io/license
-->
/**
 * WEB ANGULAR VERSION
 * (based on systemjs.config.js in angular.io)
 * System configuration for Angular samples
 * Adjust as necessary for your application needs.
 */
(function (global) {
  System.config({
    // DEMO ONLY! REAL CODE SHOULD NOT TRANSPILE IN THE BROWSER
    transpiler: 'ts',
    typescriptOptions: {
      // Copy of compiler options in standard tsconfig.json
      "target": "es5",
      "module": "system",
      "moduleResolution": "node",
      "sourceMap": true,
      "emitDecoratorMetadata": true,
      "experimentalDecorators": true,
      "noImplicitAny": true,
      "suppressImplicitAnyIndexErrors": true
    },
    meta: {
      'typescript': {
        "exports": "ts"
      }
    },
    paths: {
      // paths serve as alias
      'npm:': 'https://unpkg.com/'
    },
    // map tells the System loader where to look for things
    map: {
      // our app is within the app folder
      app: 'app',

     // angular bundles
      '@angular/animations': 'npm:@angular/animations@5.2.9/bundles/animations.umd.js',
      '@angular/animations/browser': 'npm:@angular/animations@5.2.9/bundles/animations-browser.umd.js',
      '@angular/core': 'npm:@angular/core@5.2.9/bundles/core.umd.js',
      '@angular/common': 'npm:@angular/common@5.2.9/bundles/common.umd.js',
      '@angular/compiler': 'npm:@angular/compiler@5.2.9/bundles/compiler.umd.js',
      '@angular/platform-browser': 'npm:@angular/platform-browser@5.2.9/bundles/platform-browser.umd.js',
      '@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic@5.2.9/bundles/platform-browser-dynamic.umd.js',
      '@angular/platform-browser/animations': 'npm:@angular/platform-browser@5.2.9/bundles/platform-browser-animations.umd.js',
      '@angular/common/http': 'npm:@angular/common@5.2.9/bundles/common-http.umd.js',
      '@angular/router': 'npm:@angular/router@5.2.9/bundles/router.umd.js',
      '@angular/forms': 'npm:@angular/forms@5.2.9/bundles/forms.umd.js',
      '@angular/upgrade': 'npm:@angular/upgrade@5.2.9/bundles/upgrade.umd.js',
      '@angular/upgrade/static': 'npm:@angular/upgrade@5.2.9/bundles/upgrade-static.umd.js',

      // other libraries
      'rxjs':                      'npm:rxjs',
      'tslib':                     'npm:tslib/tslib.js',
      'angular-in-memory-web-api': 'npm:angular-in-memory-web-api/bundles/in-memory-web-api.umd.js',
      'ts':                        'npm:plugin-typescript@4.0.10/lib/plugin.js',
      'typescript':                'npm:typescript@2.8.1/lib/typescript.js',
      'primeng':                   'npm:primeng@5.2.4'

    },
    // packages tells the System loader how to load when no filename and/or no extension
    packages: {
      app: {
        main: './main.ts',
        defaultExtension: 'ts'
      },
      rxjs: {
        defaultExtension: 'js'
      },
      primeng: {
        defaultExtension: 'js'
      }
    }
  });

  if (!global.noBootstrap) { bootstrap(); }

  // Bootstrap the `AppModule`(skip the `app/main.ts` that normally does this)
  function bootstrap() {
    console.log('Auto-bootstrapping');

    // Stub out `app/main.ts` so System.import('app') doesn't fail if called in the index.html
    System.set(System.normalizeSync('app/main.ts'), System.newModule({ }));

    // bootstrap and launch the app (equivalent to standard main.ts)
    Promise.all([
      System.import('@angular/platform-browser-dynamic'),
      getAppModule()
    ])
    .then(function (imports) {
      var platform = imports[0];
      var app      = imports[1];
      platform.platformBrowserDynamic().bootstrapModule(app.AppModule);
    })
    .catch(function(err){ console.error(err); });
  }

  // Import AppModule or make the default AppModule if there isn't one
  // returns a promise for the AppModule
  function getAppModule() {
    if (global.noAppModule) {
      return makeAppModule();
    }
    return System.import('app/app.module').catch(makeAppModule)
  }

  function makeAppModule() {
    console.log('No AppModule; making a bare-bones, default AppModule');

    return Promise.all([
      System.import('@angular/core'),
      System.import('@angular/platform-browser'),
      System.import('app/app.component')
    ])
    .then(function (imports) {

      var core    = imports[0];
      var browser = imports[1];
      var appComp = imports[2].AppComponent;

      var AppModule = function() {}

      AppModule.annotations = [
        new core.NgModule({
          imports:      [ browser.BrowserModule ],
          declarations: [ appComp ],
          bootstrap:    [ appComp ]
        })
      ]
      return {AppModule: AppModule};
    })
  }
})(this);
Template
<br />
<p-autoComplete placeholder="Car Brands" [(ngModel)]="brands" [suggestions]="filteredBrands" (completeMethod)="filterBrands($event)" [multiple]="true">
</p-autoComplete>
<br />
Reactive
<form [formGroup]="reForm">
  <p-autoComplete placeholder="Car Brands" formControlName="brand" [suggestions]="filteredBrands" (completeMethod)="filterBrands($event)" [multiple]="true">
  </p-autoComplete>

  <!--
  <input type="search" placeholder="Enter search string" [formControl]="searchField">
  -->
</form>

<br />
<br />

<form [formGroup]="myForm" (ngSubmit)="onSubmit(myForm)">
  <input formControlName="name" placeholder="Your name">

  <p>Your choosen name: {{ myForm.get('name').value }} / {{ myForm.controls.name.value }} / {{ myForm.value.name }}</p>
  <div *ngIf="myForm.get('name').hasError('required')">
    Oops, please provide a name!
  </div>

  <input formControlName="email" placeholder="Your email">

  <div *ngIf="myForm.controls.email.hasError('pattern')">
    Oops, wrong pattern buddy!
  </div>

  <input formControlName="message" placeholder="Your message">

  <div *ngIf="myForm.controls.message.errors?.minlength">
    Write something longer please!
  </div>

  <button type="submit" [disabled]="myForm.invalid">
    Send
  </button>
</form>