import React from 'react'
import { Line, Bar } from 'react-chartjs-2'
import debounceRender from 'react-debounce-render'
import platform from 'platform'

import { downloadAsJson } from '../../../lib/json-download/index.js'

import { datasetNames } from '../data/index.js'
import { datasetTemplates, genOptions, beautifyLabels } from './chartOptions.js'

export class Chart extends React.Component {
  render() {
    let { formState, stats, nodeData } = this.props
    let { tolRange, chart } = formState
    tolRange = tolRange || []
    let labels = beautifyLabels(tolRange)
    // let labels = tolRange.map(x => Math.round(x * 1000) / 1000)
    let datasets = Object.keys(stats).map(name => ({
      ...datasetTemplates[name],
      data: stats[name]
    }))
    datasets.push({ ...datasetTemplates.numberOfNodes, data: nodeData })
    let data = { datasets, labels }
    addLegendEntry(data, `High quality mode: ${formState.highQual}`)
    addLegendEntry(data, `Platform: ${platform.description}`)
    return (
      <div className="component chartComponent">
        <h2>Chart</h2>
        {chart === 'wasmVsJs' && <WasmVsJsChart data={data} />}
        {chart === 'wasmStack' && <WasmStackChart data={data} />}
        {chart === 'simplifyJSStack' && <JsStackChart data={data} />}
      </div>
    )
  }
}

class WasmVsJsChart extends React.Component {
  constructor(props) {
    super(props)
    this.state = {
      scaleY: 'linear',
      values: 'mean'
    }
  }
  convertDataToHz(data) {
    let datasets = data.datasets
    for (let dataset of datasets.filter(d => d.id !== 'numberOfNodes')) {
      dataset.data = dataset.data.map(mean => 1000 / mean)
    }
  }

  render() {
    let data = JSON.parse(JSON.stringify(this.props.data)) // deep copy
    let options = genOptions(
      'Simplify.wasm vs. Simplify.js',
      false,
      this.state.scaleY,
      this.state.values
    )
    if (this.state.values === 'hz') this.convertDataToHz(data)
    return (
      <>
        <Line
          ref={ref => (this.ref = ref)}
          height={400}
          width={400}
          data={data}
          options={options}
        />
        <label>Scale Y-Axis</label>
        <select
          name="scaleY"
          value={this.state.scaleY}
          onChange={e => this.setState({ scaleY: e.target.value })}
        >
          <option value="linear">Linear</option>
          <option value="logarithmic">Logarithmic</option>
        </select>

        <label>Values: </label>
        <select
          name="values"
          value={this.state.values}
          onChange={e => this.setState({ values: e.target.value })}
        >
          <option value="mean">ms per operation (mean)</option>
          <option value="hz">Operations per second (hz)</option>
        </select>
        <button onClick={() => saveChart(this.ref)}>Save chart</button>
      </>
    )
  }
}

/**
 * Returns the dataset specified by label
 */
function getDataset(data, id) {
  return data.datasets.filter(d => d.id === id)[0]
}

/**
 * Takes three data arrays. Subtracts the values of arr1 and arr2 from whole.
 * This is used for calculating the time of execution in cases where the data
 * transformation is part of the whole operation.
 * Example: subtract storeCoords and loadResult from the whole simplifyWASM
 * operation to get execution time of wasm code.
 */
function calculateTimeDelta(whole, arr1, arr2) {
  const safeGet = (arr, idx) => (idx < arr.length ? arr[idx] : 0)
  return whole.map((val, i) => val - (safeGet(arr1, i) + safeGet(arr2, i)))
}

function modifyDataArrays(data, exec, pre, after, newDatasetLabel) {
  if (getDataset(data, exec) && getDataset(data, pre)) {
    data.datasets.splice(1, 0, {
      id: 'execution',
      backgroundColor: 'red',
      borderColor: 'red',
      label: newDatasetLabel,
      data: calculateTimeDelta(
        getDataset(data, exec).data,
        getDataset(data, pre).data,
        getDataset(data, after).data
      ),
      stack: 'a'
    })
    for (let dataset of data.datasets) {
      if (dataset.id === exec) {
        dataset.label = 'Total execution time'
        dataset.stack = 'b'
        dataset.backgroundColor = '#ff7a6b'
        dataset.borderColor = '#ff7a6b'
      }
    }
  }
}

class WasmStackChart extends React.Component {
  render() {
    const data = this.props.data
    modifyDataArrays(
      data,
      'simplifyWASM',
      'storeCoords',
      'loadResult',
      'Simplification'
    )
    const options = genOptions('Simplify.wasm runtime insights', true)
    return (
      <>
        <Bar
          ref={ref => (this.ref = ref)}
          height={400}
          width={400}
          data={data}
          options={options}
        />
        <button onClick={() => saveChart(this.ref)}>Save chart</button>
      </>
    )
  }
}

class JsStackChart extends React.Component {
  render() {
    const data = this.props.data
    const options = genOptions(
      'Simplify.js with coordinates transformation',
      true
    )
    modifyDataArrays(
      data,
      'origSimplifyWithTransformCase',
      'transformToObjectFormCase',
      'transformToArrayFormCase',
      'Simplification'
    )
    return (
      <>
        <Bar
          ref={ref => (this.ref = ref)}
          height={400}
          width={400}
          data={data}
          options={options}
        />
        <button onClick={() => saveChart(this.ref)}>Save chart</button>
      </>
    )
  }
}

export const DebouncedChart = debounceRender(Chart, 300)

/**
 * Downloads the chart config as json
 */
function saveChart(chartRef) {
  let myChart = chartRef.chartInstance.config
  let config = JSON.stringify(myChart, (key, val) =>
    key === '_meta' ? undefined : val
  )
  downloadAsJson(config, 'config.json')
}

/**
 * Adds an empty dataset to attach info to legend
 * @param {} data
 * @param {*} label
 */
function addLegendEntry(data, label) {
  data.datasets.push({ label, data: [] })
}