import { observable, computed } from 'mobx'
import { asyncComputed } from 'computed-async-mobx'

import algorithms from './algorithms/index.js'

class State {
  @observable tileLayer = 'osmDE'
  @observable originalActive = true
  @observable simplifiedActive = true

  @observable algorithmId = 'nth_point'
  @observable topoJSON = false
  @computed
  get selectedAlgorithm() {
    return algorithms.filter(algo => algo.id === this.algorithmId)[0]
  }
  @computed
  get algoParams() {
    return this.selectedAlgorithm.fields.map(f => f.value)
  }

  @observable originalText = '{"type": "FeatureCollection", "features": []}'
  @observable originalName = ''
  @computed
  get original() {
    return JSON.parse(this.originalText)
  }

  simplifiedPromise = asyncComputed(this.original, 500, async () => {
    return await this.selectedAlgorithm.simplifyGeoJSON(
      this.original,
      this.algoParams
    )
  })

  @computed
  get simplified() {
    return this.simplifiedPromise.get()
  }
  @computed
  get simplifiedText() {
    return JSON.stringify(this.simplified)
  }
}

export default new State()