# All files / components Axes.tsx

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     import React, {
      CSSProperties,
      FunctionComponent,
      RefObject,
      useLayoutEffect,
    } from 'react'

    import {TICK_PADDING_RIGHT, TICK_PADDING_TOP} from '../constants'
    import {clearCanvas} from '../utils/clearCanvas'
    import {Margins, Scale, SizedConfig, Formatter, ColumnType} from '../types'

    import {PlotEnv} from '../utils/PlotEnv'

    interface Props {
      canvasRef: RefObject<HTMLCanvasElement>
      env: PlotEnv
      style: CSSProperties
    }

    // A grid line must be at least this many pixels away from both parallel axes
    // in order to be drawn
    const GRID_LINE_MIN_DIST = 5

    interface DrawAxesOptions {
      canvas: HTMLCanvasElement
      innerWidth: number
      innerHeight: number
      margins: Margins
      xDomain: number[]
      yDomain: number[]
      xTicks: number[]
      yTicks: Array<number | string>
      xTickFormatter: Formatter
      yTickFormatter: Formatter
      xScale: Scale<number, number>
      yScale: Scale<number, number>
      config: SizedConfig
      yColumnType?: ColumnType
    }

    export const drawAxes = ({
      canvas,
      innerWidth,
      innerHeight,
      margins,
      xDomain,
      yDomain,
      xTicks,
      yTicks,
      xTickFormatter,
      yTickFormatter,
      xScale,
      yScale,
      config: {
        width,
        height,
        axisColor,
        axisOpacity,
        gridColor,
        gridOpacity,
        tickFont,
        tickFontColor,
        xAxisLabel,
        yAxisLabel,
      },
    }: DrawAxesOptions) => {
      clearCanvas(canvas, width, height)

      const context = canvas.getContext('2d')
      const xAxisY = height - margins.bottom
      const xDomainWidth = Math.abs(xDomain[1] - xDomain[0])

      // Draw and label each tick on the x axis

      context.font = tickFont
      context.textAlign = 'center'
      context.textBaseline = 'top'

      for (const xTick of xTicks) {
        const x = xScale(xTick) + margins.left

        if (
          Math.abs(x - margins.left) > GRID_LINE_MIN_DIST &&
          Math.abs(x - (width - margins.right)) > GRID_LINE_MIN_DIST
        ) {
          context.strokeStyle = gridColor
          context.globalAlpha = gridOpacity
          context.beginPath()
          context.moveTo(x, xAxisY)
          context.lineTo(x, margins.top)
          context.stroke()
        }

        context.globalAlpha = 1
        context.fillStyle = tickFontColor
        context.fillText(
          xTickFormatter(xTick, {domainWidth: xDomainWidth}),
          x,
          xAxisY + TICK_PADDING_TOP
        )
      }

      // Draw and label each tick on the y axis
      context.textAlign = 'end'
      context.textBaseline = 'middle'
      const yDomainWidth = yDomain[1] - yDomain[0]
      let count = 0
      for (const yTick of yTicks) {
        let y
        if (typeof yTick === 'string') {
          y = yScale(count) + margins.top - height / (yTicks.length * 2)
          context.globalAlpha = 1
          context.fillStyle = tickFontColor

          context.fillText(
            yTickFormatter(yTick, {domainWidth: yDomainWidth}),
            margins.left - TICK_PADDING_RIGHT,
            y
          )
          count += 1
        } else {
          y = yScale(yTick) + margins.top
          if (
            Math.abs(y - margins.top) > GRID_LINE_MIN_DIST &&
            Math.abs(y - (height - margins.bottom)) > GRID_LINE_MIN_DIST
          ) {
            context.strokeStyle = gridColor
            context.globalAlpha = gridOpacity
            context.beginPath()
            context.moveTo(margins.left, y)
            context.lineTo(width - margins.right, y)
            context.stroke()
          }

          context.globalAlpha = 1
          context.fillStyle = tickFontColor
          context.fillText(
            yTickFormatter(yTick, {domainWidth: yDomainWidth}),
            margins.left - TICK_PADDING_RIGHT,
            y
          )
        }
      }

      // Draw x and y axis lines

      context.globalAlpha = axisOpacity
      context.strokeStyle = axisColor

      context.beginPath()
      context.moveTo(margins.left, xAxisY)
      context.lineTo(width - margins.right, xAxisY)
      context.stroke()

      context.beginPath()
      context.moveTo(margins.left, margins.top)
      context.lineTo(width - margins.right, margins.top)
      context.stroke()

      context.beginPath()
      context.moveTo(margins.left, xAxisY)
      context.lineTo(margins.left, margins.top)
      context.stroke()

      context.beginPath()
      context.moveTo(width - margins.right, xAxisY)
      context.lineTo(width - margins.right, margins.top)
      context.stroke()

      context.globalAlpha = 1

      // Draw the x axis label
      if (xAxisLabel) {
        context.textAlign = 'center'
        context.textBaseline = 'bottom'
        context.fillText(xAxisLabel, margins.left + innerWidth / 2, height)
      }

      // Draw the y axis label
      if (yAxisLabel) {
        const x = 0
        const y = margins.top + innerHeight / 2

        context.save()
        context.translate(x, y)
        context.rotate(-Math.PI / 2)
        context.textAlign = 'center'
        context.textBaseline = 'top'
        context.fillText(yAxisLabel, 0, 0)
        context.restore()
      }
    }

    export const Axes: FunctionComponent<Props> = ({canvasRef, env, style}) => {
      const {
        innerWidth,
        innerHeight,
        margins,
        xDomain,
        yDomain,
        xTicks,
        yTicks,
        xTickFormatter,
        yTickFormatter,
        xScale,
        yScale,
        config,
        yColumnType,
      } = env

      useLayoutEffect(() => {
        drawAxes({
          canvas: canvasRef.current,
          innerWidth,
          innerHeight,
          margins,
          xDomain,
          yDomain,
          xTicks,
          yTicks,
          xTickFormatter,
          yTickFormatter,
          xScale,
          yScale,
          config,
          yColumnType,
        })
      }, [
        canvasRef.current,
        innerWidth,
        innerHeight,
        margins,
        xDomain,
        yDomain,
        xTicks,
        yTicks,
        xTickFormatter,
        yTickFormatter,
        xScale,
        yScale,
        config,
        yColumnType,
      ])
      return (
        <canvas
          className="giraffe-axes"
          ref={canvasRef}
          style={style}
          data-testid="giraffe-axes"
        />
      )
    }

    Axes.displayName = 'Axes'