index.js

const svgToDataUri = require('mini-svg-data-uri')
const plugin = require('tailwindcss/plugin')
const defaultTheme = require('tailwindcss/defaultTheme')
const colors = require('tailwindcss/colors')
const [baseFontSize, { lineHeight: baseLineHeight }] = defaultTheme.fontSize.base
const { spacing, borderWidth, borderRadius } = defaultTheme

function resolveColor(color, opacityVariableName) {
  return color.replace('<alpha-value>', `var(${opacityVariableName}, 1)`)
}

const forms = plugin.withOptions(function (options = { strategy: undefined }) {
  return function ({ addBase, addComponents, theme }) {
    const strategy = options.strategy === undefined ? ['base', 'class'] : [options.strategy]

    const rules = [
      {
        base: [
          "input:where([type='text'])",
          'input:where(:not([type]))',
          "input:where([type='email'])",
          "input:where([type='url'])",
          "input:where([type='password'])",
          "input:where([type='number'])",
          "input:where([type='date'])",
          "input:where([type='datetime-local'])",
          "input:where([type='month'])",
          "input:where([type='search'])",
          "input:where([type='tel'])",
          "input:where([type='time'])",
          "input:where([type='week'])",
          'select:where([multiple])',
          'textarea',
          'select',
        ],
        class: ['.form-input', '.form-textarea', '.form-select', '.form-multiselect'],
        styles: {
          appearance: 'none',
          'background-color': '#fff',
          'border-color': resolveColor(
            theme('colors.gray.500', colors.gray[500]),
            '--tw-border-opacity'
          ),
          'border-width': borderWidth['DEFAULT'],
          'border-radius': borderRadius.none,
          'padding-top': spacing[2],
          'padding-right': spacing[3],
          'padding-bottom': spacing[2],
          'padding-left': spacing[3],
          'font-size': baseFontSize,
          'line-height': baseLineHeight,
          '--tw-shadow': '0 0 #0000',
          '&:focus': {
            outline: '2px solid transparent',
            'outline-offset': '2px',
            '--tw-ring-inset': 'var(--tw-empty,/*!*/ /*!*/)',
            '--tw-ring-offset-width': '0px',
            '--tw-ring-offset-color': '#fff',
            '--tw-ring-color': resolveColor(
              theme('colors.blue.600', colors.blue[600]),
              '--tw-ring-opacity'
            ),
            '--tw-ring-offset-shadow': `var(--tw-ring-inset) 0 0 0 var(--tw-ring-offset-width) var(--tw-ring-offset-color)`,
            '--tw-ring-shadow': `var(--tw-ring-inset) 0 0 0 calc(1px + var(--tw-ring-offset-width)) var(--tw-ring-color)`,
            'box-shadow': `var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow)`,
            'border-color': resolveColor(
              theme('colors.blue.600', colors.blue[600]),
              '--tw-border-opacity'
            ),
          },
        },
      },
      {
        base: ['input::placeholder', 'textarea::placeholder'],
        class: ['.form-input::placeholder', '.form-textarea::placeholder'],
        styles: {
          color: resolveColor(theme('colors.gray.500', colors.gray[500]), '--tw-text-opacity'),
          opacity: '1',
        },
      },
      {
        base: ['::-webkit-datetime-edit-fields-wrapper'],
        class: ['.form-input::-webkit-datetime-edit-fields-wrapper'],
        styles: {
          padding: '0',
        },
      },
      {
        // Unfortunate hack until https://bugs.webkit.org/show_bug.cgi?id=198959 is fixed.
        // This sucks because users can't change line-height with a utility on date inputs now.
        // Reference: https://github.com/twbs/bootstrap/pull/31993
        base: ['::-webkit-date-and-time-value'],
        class: ['.form-input::-webkit-date-and-time-value'],
        styles: {
          'min-height': '1.5em',
        },
      },
      {
        // In Safari on iOS date and time inputs are centered instead of left-aligned and can't be
        // changed with `text-align` utilities on the input by default. Resetting this to `inherit`
        // makes them left-aligned by default and makes it possible to override the alignment with
        // utility classes without using an arbitrary variant to target the pseudo-elements.
        base: ['::-webkit-date-and-time-value'],
        class: ['.form-input::-webkit-date-and-time-value'],
        styles: {
          'text-align': 'inherit',
        },
      },
      {
        // In Safari on macOS date time inputs that are set to `display: block` have unexpected
        // extra bottom spacing. This can be corrected by setting the `::-webkit-datetime-edit`
        // pseudo-element to `display: inline-flex`, instead of the browser default of
        // `display: inline-block`.
        base: ['::-webkit-datetime-edit'],
        class: ['.form-input::-webkit-datetime-edit'],
        styles: {
          display: 'inline-flex',
        },
      },
      {
        // In Safari on macOS date time inputs are 4px taller than normal inputs
        // This is because there is extra padding on the datetime-edit and datetime-edit-{part}-field pseudo elements
        // See https://github.com/tailwindlabs/tailwindcss-forms/issues/95
        base: [
          '::-webkit-datetime-edit',
          '::-webkit-datetime-edit-year-field',
          '::-webkit-datetime-edit-month-field',
          '::-webkit-datetime-edit-day-field',
          '::-webkit-datetime-edit-hour-field',
          '::-webkit-datetime-edit-minute-field',
          '::-webkit-datetime-edit-second-field',
          '::-webkit-datetime-edit-millisecond-field',
          '::-webkit-datetime-edit-meridiem-field',
        ],
        class: [
          '.form-input::-webkit-datetime-edit',
          '.form-input::-webkit-datetime-edit-year-field',
          '.form-input::-webkit-datetime-edit-month-field',
          '.form-input::-webkit-datetime-edit-day-field',
          '.form-input::-webkit-datetime-edit-hour-field',
          '.form-input::-webkit-datetime-edit-minute-field',
          '.form-input::-webkit-datetime-edit-second-field',
          '.form-input::-webkit-datetime-edit-millisecond-field',
          '.form-input::-webkit-datetime-edit-meridiem-field',
        ],
        styles: {
          'padding-top': 0,
          'padding-bottom': 0,
        },
      },
      {
        base: ['select'],
        class: ['.form-select'],
        styles: {
          'background-image': `url("${svgToDataUri(
            `<svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 20 20"><path stroke="${resolveColor(
              theme('colors.gray.500', colors.gray[500]),
              '--tw-stroke-opacity'
            )}" stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M6 8l4 4 4-4"/></svg>`
          )}")`,
          'background-position': `right ${spacing[2]} center`,
          'background-repeat': `no-repeat`,
          'background-size': `1.5em 1.5em`,
          'padding-right': spacing[10],
          'print-color-adjust': `exact`,
        },
      },
      {
        base: ['select:where([multiple])', 'select:where([size]:not([size="1"]))'],
        class: ['.form-select:where([size]:not([size="1"]))'],
        styles: {
          'background-image': 'initial',
          'background-position': 'initial',
          'background-repeat': 'unset',
          'background-size': 'initial',
          'padding-right': spacing[3],
          'print-color-adjust': 'unset',
        },
      },
      {
        base: [`input:where([type='checkbox'])`, `input:where([type='radio'])`],
        class: ['.form-checkbox', '.form-radio'],
        styles: {
          appearance: 'none',
          padding: '0',
          'print-color-adjust': 'exact',
          display: 'inline-block',
          'vertical-align': 'middle',
          'background-origin': 'border-box',
          'user-select': 'none',
          'flex-shrink': '0',
          height: spacing[4],
          width: spacing[4],
          color: resolveColor(theme('colors.blue.600', colors.blue[600]), '--tw-text-opacity'),
          'background-color': '#fff',
          'border-color': resolveColor(
            theme('colors.gray.500', colors.gray[500]),
            '--tw-border-opacity'
          ),
          'border-width': borderWidth['DEFAULT'],
          '--tw-shadow': '0 0 #0000',
        },
      },
      {
        base: [`input:where([type='checkbox'])`],
        class: ['.form-checkbox'],
        styles: {
          'border-radius': borderRadius['none'],
        },
      },
      {
        base: [`input:where([type='radio'])`],
        class: ['.form-radio'],
        styles: {
          'border-radius': '100%',
        },
      },
      {
        base: [`input:where([type='checkbox']):focus`, `input:where([type='radio']):focus`],
        class: ['.form-checkbox:focus', '.form-radio:focus'],
        styles: {
          outline: '2px solid transparent',
          'outline-offset': '2px',
          '--tw-ring-inset': 'var(--tw-empty,/*!*/ /*!*/)',
          '--tw-ring-offset-width': '2px',
          '--tw-ring-offset-color': '#fff',
          '--tw-ring-color': resolveColor(
            theme('colors.blue.600', colors.blue[600]),
            '--tw-ring-opacity'
          ),
          '--tw-ring-offset-shadow': `var(--tw-ring-inset) 0 0 0 var(--tw-ring-offset-width) var(--tw-ring-offset-color)`,
          '--tw-ring-shadow': `var(--tw-ring-inset) 0 0 0 calc(2px + var(--tw-ring-offset-width)) var(--tw-ring-color)`,
          'box-shadow': `var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow)`,
        },
      },
      {
        base: [`input:where([type='checkbox']):checked`, `input:where([type='radio']):checked`],
        class: ['.form-checkbox:checked', '.form-radio:checked'],
        styles: {
          'border-color': `transparent`,
          'background-color': `currentColor`,
          'background-size': `100% 100%`,
          'background-position': `center`,
          'background-repeat': `no-repeat`,
        },
      },
      {
        base: [`input:where([type='checkbox']):checked`],
        class: ['.form-checkbox:checked'],
        styles: {
          'background-image': `url("${svgToDataUri(
            `<svg viewBox="0 0 16 16" fill="white" xmlns="http://www.w3.org/2000/svg"><path d="M12.207 4.793a1 1 0 010 1.414l-5 5a1 1 0 01-1.414 0l-2-2a1 1 0 011.414-1.414L6.5 9.086l4.293-4.293a1 1 0 011.414 0z"/></svg>`
          )}")`,

          '@media (forced-colors: active) ': {
            appearance: 'auto',
          },
        },
      },
      {
        base: [`input:where([type='radio']):checked`],
        class: ['.form-radio:checked'],
        styles: {
          'background-image': `url("${svgToDataUri(
            `<svg viewBox="0 0 16 16" fill="white" xmlns="http://www.w3.org/2000/svg"><circle cx="8" cy="8" r="3"/></svg>`
          )}")`,

          '@media (forced-colors: active) ': {
            appearance: 'auto',
          },
        },
      },
      {
        base: [
          `input:where([type='checkbox']):checked:hover`,
          `input:where([type='checkbox']):checked:focus`,
          `input:where([type='radio']):checked:hover`,
          `input:where([type='radio']):checked:focus`,
        ],
        class: [
          '.form-checkbox:checked:hover',
          '.form-checkbox:checked:focus',
          '.form-radio:checked:hover',
          '.form-radio:checked:focus',
        ],
        styles: {
          'border-color': 'transparent',
          'background-color': 'currentColor',
        },
      },
      {
        base: [`input:where([type='checkbox']):indeterminate`],
        class: ['.form-checkbox:indeterminate'],
        styles: {
          'background-image': `url("${svgToDataUri(
            `<svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 16 16"><path stroke="white" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 8h8"/></svg>`
          )}")`,
          'border-color': `transparent`,
          'background-color': `currentColor`,
          'background-size': `100% 100%`,
          'background-position': `center`,
          'background-repeat': `no-repeat`,

          '@media (forced-colors: active) ': {
            appearance: 'auto',
          },
        },
      },
      {
        base: [`input:where([type='checkbox']):indeterminate:hover`, `input:where([type='checkbox']):indeterminate:focus`],
        class: ['.form-checkbox:indeterminate:hover', '.form-checkbox:indeterminate:focus'],
        styles: {
          'border-color': 'transparent',
          'background-color': 'currentColor',
        },
      },
      {
        base: [`input:where([type='file'])`],
        class: null,
        styles: {
          background: 'unset',
          'border-color': 'inherit',
          'border-width': '0',
          'border-radius': '0',
          padding: '0',
          'font-size': 'unset',
          'line-height': 'inherit',
        },
      },
      {
        base: [`input:where([type='file']):focus`],
        class: null,
        styles: {
          outline: [`1px solid ButtonText`, `1px auto -webkit-focus-ring-color`],
        },
      },
    ]

    const getStrategyRules = (strategy) =>
      rules
        .map((rule) => {
          if (rule[strategy] === null) return null

          return { [rule[strategy]]: rule.styles }
        })
        .filter(Boolean)

    if (strategy.includes('base')) {
      addBase(getStrategyRules('base'))
    }

    if (strategy.includes('class')) {
      addComponents(getStrategyRules('class'))
    }
  }
})

module.exports = forms