/********************************************************************************
 * 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 { Component, ViewChild, Input, OnChanges, SimpleChanges } from '@angular/core';

import { LazyLoadEvent, Column } from 'primeng/primeng';
import { Table } from 'primeng/table';

import { Node } from '../../../navigator/node';
import { ChartViewerDataService, getDataArray } from '../../services/chart-viewer-data.service';
import { MeasuredValues } from '../../model/chartviewer.model';

@Component({
  selector: 'mdm5-dataTable',
  templateUrl: 'data-table.component.html',
  providers: []
})
export class DataTableComponent implements OnChanges {
  @ViewChild('datatable')
  private table: Table;

  @Input()
  channelGroup = new Node();
  @Input()
  channels = [new Node()];

  tableLoading = false;
  cols: Column[] = [];
  totalRecords = 0;
  recordsPerPage = 10;
  datapoints = [];

  constructor(private chartviewerService: ChartViewerDataService) {
  }

  ngOnChanges(changes: SimpleChanges) {
    for (let propName in changes) {
      if (propName === 'channelGroup' || propName === 'channels') {
        this.table.reset();
      }
    }
  }

  load(mv: MeasuredValues[]) {
    let zip = (rows => rows[0].map((_, c) => rows.map(row => row[c])));

    this.cols = mv.map((m, i) => Object.assign(new Column(), { header: m.name, field: i }));
    this.datapoints = zip(mv.map(m => getDataArray(m).values));
  }

  loadLazy(event: LazyLoadEvent) {
    if (this.channelGroup === undefined) {
      return;
    }

    setTimeout(() => {
      this.tableLoading = true;
      this.totalRecords = this.chartviewerService.getNumberOfRows(this.channelGroup);
      this.chartviewerService.loadMeasuredValues(this.channelGroup, this.channels, event.first, event.rows).subscribe(mv => {
        this.load(mv);
        this.tableLoading = false;
      },
      () => this.tableLoading = false);
    }, 0);
  }
}