import React, { Component } from 'react'
// import { Link } from 'react-router-dom'
// import { bindActionCreators } from 'redux'
import { connect } from 'react-redux'

import actions from '../../../actions'
// import * as uploadActions from './upload.actions'

import Ticks from './ticks.component'

import { DEFAULT_HEIGHT, WAVEFORM_HEIGHT, ZOOM_STEPS, ZOOM_LABEL_STEPS, ZOOM_TICK_STEPS } from '../constants'

class Timeline extends Component {
  constructor(props){
    super(props)
    this.canvasRef = React.createRef()
    this.handleKeydown = this.handleKeydown.bind(this)
  }
  componentDidMount() {
    this.bind()
    this.resize()
    this.draw()
  }
  componentDidUpdate() {
    this.draw()
  }
  componentWillUnmount() {
    this.unbind()
  }
  bind() {
    document.addEventListener('keydown', this.handleKeydown)
  }
  unbind() {
    document.removeEventListener('keydown', this.handleKeydown)
  }
  handleKeydown(e) {
    // console.log(e.shiftKey, e.keyCode)
  }
  resize() {
    const canvas = this.canvasRef.current
    canvas.width = window.innerWidth
    canvas.height = DEFAULT_HEIGHT
  }
  draw() {
    const canvas = this.canvasRef.current
    const ctx = canvas.getContext('2d')
    const w = window.innerWidth
    this.clearCanvas(ctx, w)
    this.drawCurve(ctx, w)
  }
  clearCanvas(ctx, w) {  
    const h = WAVEFORM_HEIGHT
    ctx.clearRect(0, 0, w, h)
    ctx.fillStyle = 'rgba(0,0,0,0.5)'
    ctx.fillRect(0, 0, w, h)
    ctx.fillStyle = 'rgba(64,128,192,0.5)'
  }
  drawCurve(ctx, w) {
    let { peaks, timeline } = this.props
    let { start_ts, zoom, duration } = timeline
    let stepsPerPixel = ZOOM_STEPS[zoom] // 0.1 sec / step
    let indexesPerPixel = stepsPerPixel * 2
    let stepMin = start_ts * 10
    let stepDuration = duration * 10 / stepsPerPixel
    let stepMax = stepDuration - stepMin
    let stepWidth = Math.min(stepMax, w)
    stepWidth += 2 + (stepWidth % 2)
    let i = 0
    let step = stepMin
    let waveformPeak = WAVEFORM_HEIGHT / 2
    let origin = (1 - peaks[step]) * waveformPeak
    let y = origin
    let peak
    ctx.beginPath()
    ctx.moveTo(0, y)
    for (i = 0; i < stepWidth; i++) {
      step = i * indexesPerPixel + stepMin
      peak = peaks[step]
      y = (1 - peak) * waveformPeak
      ctx.lineTo(i, y)
    }
    for (i = stepWidth - 1; i > 0; i--) {
      step = i * indexesPerPixel + stepMin
      peak = peaks[step]
      y = (1 + peaks[step]) * waveformPeak
      ctx.lineTo(i, y)
    }
    ctx.lineTo(0, origin)
    ctx.fillStyle = 'rgba(255,255,255,0.8)'
    ctx.fill()
  }
  render() {
    return (
      <div className='timeline'>
        <canvas ref={this.canvasRef} />
        <Ticks timeline={this.props.timeline} />
      </div>
    )
  }
}

const mapStateToProps = state => ({
  timeline: state.align.timeline,
  peaks: state.site.peaks,
})

const mapDispatchToProps = dispatch => ({
  // uploadActions: bindActionCreators({ ...uploadActions }, dispatch),
})

export default connect(mapStateToProps, mapDispatchToProps)(Timeline)