import {Observable} from 'rxjs';
import {Component, Injectable, Input, OnInit} from '@angular/core';
import {Store} from '@ngrx/store';
import * as mapReducers from '../../reducers/map.reducer';
import {commonReducers, IItem, IListItem, ItemService, ItemTypeService} from '@farmmaps/common';
import {ForItemType} from '../for-item/for-itemtype.decorator';
import {ForSourceTask} from '../for-item/for-sourcetask.decorator';
import {AbstractItemListItemComponent} from '../item-list-item/item-list-item.component'
import {map} from "rxjs/operators";

@ForItemType("vnd.farmmaps.itemtype.geotiff.processed")
@ForSourceTask("vnd.farmmaps.task.shadow")
@Injectable()
@Component({
  selector: 'item-list-item-shadow',
  templateUrl: './item-list-item-shadow.component.html',
  styleUrls: ['./item-list-item-shadow.component.scss']
})
export class ItemListItemShadowComponent extends AbstractItemListItemComponent implements OnInit {
  @Input() item: IListItem;
  selectedItem: Observable<IItem>;

  public sunCenter = {x: 235.9, y: 259.4};
  public sunStart = {x: 0, y: 0};
  public sunEndRelative = {x: 0, y: 0};
  public largeArc = 0;
  public radius = 120;

  public sunColor = '#ffcc00';

  constructor(store: Store<mapReducers.State | commonReducers.State>, itemTypeService: ItemTypeService,
              private itemService$: ItemService) {
    super(store, itemTypeService);
  }

  ngOnInit() {
    this.selectedItem = this.itemService$.getItem(this.item.code)
      .pipe(map(item => {
        const shadowIndex = this.getMeanShadowValue(item);
        this.calculateSunValues(shadowIndex);
        return item;
      }));
  }

  calculateSunValues(shadowIndex) {
    const dotProduct = shadowIndex * 2 - 1;
    this.largeArc = dotProduct > 0 ? 1 : 0;

    const angle = Math.acos(dotProduct);
    const yRadius = this.radius * Math.sin(-angle);

    this.sunStart.x = this.sunCenter.x + this.radius * dotProduct;
    this.sunStart.y = this.sunCenter.y + yRadius;
    this.sunEndRelative.x = this.sunStart.x;
    this.sunEndRelative.y = this.sunCenter.y - yRadius;
  }

  getSunShadowPath() {
    return `M${this.sunStart.x} ${this.sunStart.y} A${this.radius},${this.radius} 0 ${this.largeArc},0 ${this.sunEndRelative.x} ${this.sunEndRelative.y}z`;
  }

  getMeanShadowValue(item): number {
    return item.data.layers[0].renderer.band.histogram.mean;
  }
}