import React from 'react'
import sanitize from 'html-react-parser'

const style = { fill: 'none', stroke: 'currentColor' }

const StackDefs = ({ stacks }) =>
  Object.keys(stacks).map((stackName) => {
    const part = stacks[stackName].parts[0]
    let anchor = { x: 0, y: 0 }
    if (typeof part.points.gridAnchor !== 'undefined') anchor = part.points.gridAnchor
    else if (typeof part.points.anchor !== 'undefined') anchor = part.points.anchor

    if (isNaN(anchor.x)) anchor.x = 0
    if (isNaN(anchor.y)) anchor.y = 0

    return (
      <pattern
        id={`grid-${stackName}`}
        key={`grid-${stackName}`}
        xlinkHref="#grid"
        x={anchor.x}
        y={anchor.y}
      />
    )
  })

const MetricPaperlessDefs = ({ stacks }) => (
  <>
    <pattern id="grid" height="100" width="100" patternUnits="userSpaceOnUse" key="grid">
      <path style={style} className="gridline lg metric" d="M 0 0 L 0 100 L 100 100" />
      <path style={style} className="gridline metric" d="M 50 0 L 50 100 M 0 50 L 100 50" />
      <path
        style={style}
        className="gridline sm metric"
        d="M 10 0 L 10 100 M 20 0 L 20 100 M 30 0 L 30 100 M 40 0 L 40 100 M 60 0 L 60 100 M 70 0 L 70 100 M 80 0 L 80 100 M 90 0 L 90 100"
      />
      <path
        style={style}
        className="gridline sm metric"
        d="M 0 10 L 100 10 M 0 20 L 100 20 M 0 30 L 100 30 M 0 40 L 100 40 M 0 60 L 100 60 M 0 70 L 100 70 M 0 80 L 100 80 M 0 90 L 100 90"
      />
      <path
        style={style}
        className="gridline xs metric"
        d="M 5 0 L 5 100 M 15 0 L 15 100 M 25 0 L 25 100 M 35 0 L 35 100 M 45 0 L 45 100 M 55 0 L 55 100 M 65 0 L 65 100 M 75 0 L 75 100 M 85 0 L 85 100 M 95 0 L 95 100"
      />
      <path
        style={style}
        className="gridline xs metric"
        d="M 0 5 L 100 5 M 0 15 L 100 15 M 0 25 L 100 25 M 0 35 L 100 35 M 0 45 L 100 45 M 0 55 L 100 55 M 0 65 L 100 65 M 0 75 L 100 75 M 0 85 L 100 85 M 0 95 L 100 95"
      />
    </pattern>
    <StackDefs stacks={stacks} />
  </>
)

const ImperialPaperlessDefs = ({ stacks }) => (
  <>
    <pattern id="grid" height="25.4" width="25.4" patternUnits="userSpaceOnUse" key="grid">
      <path style={style} className="gridline lg imperial" d="M 0 0 L 0 25.4 L 25.4 25.4" />
      <path
        style={style}
        className="gridline lg imperial"
        d="M 12.7 0 L 12.7 25.4 M 0 12.7 L 25.4 12.7"
      />
      <path
        style={style}
        className="gridline sm imperial"
        d="M 3.175 0 L 3.175 25.4 M 6.32 0 L 6.35 25.4 M 9.525 0 L 9.525 25.4 M 15.875 0 L 15.875 25.4 M 19.05 0 L 19.05 25.4 M 22.225 0 L 22.225 25.4"
      />
      <path
        style={style}
        className="gridline sm imperial"
        d="M 0 3.175 L 25.4 3.175 M 0 6.32 L 25.4 6.35 M 0 9.525 L 25.4 9.525 M 0 15.875 L 25.4 15.875 M 0 19.05 L 25.4 19.05 M 0 22.225 L 25.4 22.225"
      />
    </pattern>
    <StackDefs stacks={stacks} />
  </>
)

const PaperlessDefs = ({ units = 'metric', stacks }) =>
  units === 'imperial' ? (
    <ImperialPaperlessDefs stacks={stacks} />
  ) : (
    <MetricPaperlessDefs stacks={stacks} />
  )

/**
 * A component to render the defs section of an SVG element inside a FreeSewing pattern
 *
 * @component
 * @param {object} props - All component props
 * @param {Svg} props.svg - The FreeSewing Svg object for the pattern
 * @param {object} props.settings - The settings for the pattern
 * @param {object} props.stacks - The pattern stacks
 * @returns {JSX.Element}
 */
export const Defs = ({ svg, stacks, settings = {} }) =>
  svg ? (
    <defs>
      {svg.defs.list ? sanitize(Object.values(svg.defs.list).join('')) : null}
      {settings[0]?.paperless ? <PaperlessDefs units={settings[0].units} stacks={stacks} /> : null}
    </defs>
  ) : null