maputnik/src/components/fields/ZoomSpecField.jsx

import React from 'react'
import Color from 'color'

import Button from '../Button'
import SpecField from './SpecField'
import NumberInput from '../inputs/NumberInput'
import DocLabel from './DocLabel'
import InputBlock from '../inputs/InputBlock'

import AddIcon from 'react-icons/lib/md/add-circle-outline'
import DeleteIcon from 'react-icons/lib/md/delete'
import FunctionIcon from 'react-icons/lib/md/functions'

import capitalize from 'lodash.capitalize'

function isZoomField(value) {
  return typeof value === 'object' && value.stops
}

/** Supports displaying spec field for zoom function objects
 * https://www.mapbox.com/mapbox-gl-style-spec/#types-function-zoom-property
 */
export default class ZoomSpecProperty  extends React.Component {
  static propTypes = {
      onChange: React.PropTypes.func.isRequired,
      fieldName: React.PropTypes.string.isRequired,
      fieldSpec: React.PropTypes.object.isRequired,

      value: React.PropTypes.oneOfType([
      React.PropTypes.object,
      React.PropTypes.string,
      React.PropTypes.number,
      React.PropTypes.bool,
    ]),
  }

  addStop() {
    const stops = this.props.value.stops.slice(0)
    const lastStop = stops[stops.length - 1]
    stops.push([lastStop[0] + 1, lastStop[1]])

    const changedValue = {
      ...this.props.value,
      stops: stops,
    }

    this.props.onChange(this.props.fieldName, changedValue)
  }

  deleteStop(stopIdx) {
    const stops = this.props.value.stops.slice(0)
    stops.splice(stopIdx, 1)

    let changedValue = {
      ...this.props.value,
      stops: stops,
    }

    if(stops.length === 1) {
      changedValue = stops[0][1]
    }

    this.props.onChange(this.props.fieldName, changedValue)
  }

  makeZoomFunction() {
    const zoomFunc = {
      stops: [
        [6, this.props.value],
        [10, this.props.value]
      ]
    }
    this.props.onChange(this.props.fieldName, zoomFunc)
  }

  changeStop(changeIdx, zoomLevel, value) {
    const stops = this.props.value.stops.slice(0)
    stops[changeIdx] = [zoomLevel, value]
    const changedValue = {
      ...this.props.value,
      stops: stops,
    }
    this.props.onChange(this.props.fieldName, changedValue)
  }

  renderZoomProperty() {
    const zoomFields = this.props.value.stops.map((stop, idx) => {
      const zoomLevel = stop[0]
      const value = stop[1]
      const deleteStopBtn= <DeleteStopButton onClick={this.deleteStop.bind(this, idx)} />

      return <InputBlock
        key={zoomLevel}
        doc={this.props.fieldSpec.doc}
        label={labelFromFieldName(this.props.fieldName)}
        action={deleteStopBtn}
      >
        <div>
          <div className="maputnik-zoom-spec-property-stop-edit">
            <NumberInput
              value={zoomLevel}
              onChange={changedStop => this.changeStop(idx, changedStop, value)}
              min={0}
              max={22}
            />
          </div>
          <div className="maputnik-zoom-spec-property-stop-value">
            <SpecField
              fieldName={this.props.fieldName}
              fieldSpec={this.props.fieldSpec}
              value={value}
              onChange={(_, newValue) => this.changeStop(idx, zoomLevel, newValue)}
            />
          </div>
        </div>
      </InputBlock>
    })

    return <div className="maputnik-zoom-spec-property">
      {zoomFields}
      <Button
        className="maputnik-add-stop"
        onClick={this.addStop.bind(this)}
      >
        Add stop
      </Button>
    </div>
  }

  renderProperty() {
    let zoomBtn = null
    if(this.props.fieldSpec['zoom-function']) {
      zoomBtn = <MakeZoomFunctionButton onClick={this.makeZoomFunction.bind(this)} />
    }

    return <InputBlock
      doc={this.props.fieldSpec.doc}
      label={labelFromFieldName(this.props.fieldName)}
      action={zoomBtn}
    >
      <SpecField {...this.props} />
    </InputBlock>
  }

  render() {
    if(isZoomField(this.props.value)) {
      return this.renderZoomProperty();
    } else {
      return this.renderProperty();
    }
  }
}

function MakeZoomFunctionButton(props) {
  return <Button
    className="maputnik-make-zoom-function"
    onClick={props.onClick}
  >
    <DocLabel
      label={<FunctionIcon />}
      cursorTargetStyle={{ cursor: 'pointer' }}
      doc={"Turn property into a zoom function to enable a map feature to change with map's zoom level."}
    />
  </Button>
}

function DeleteStopButton(props) {
  return <Button
    className="maputnik-delete-stop"
    onClick={props.onClick}
  >
    <DocLabel
      label={<DeleteIcon />}
      doc={"Remove zoom level stop."}
    />
  </Button>
}

function labelFromFieldName(fieldName) {
  let label = fieldName.split('-').slice(1).join(' ')
  return capitalize(label)
}