Combobox

'use client'

import { useState } from 'react'
import { Combobox } from '@/components/ui/combobox'
import { Field } from '@/components/ui/field'
import { DemoColumn, DemoStage } from './_kit'

const repositories = [
  { value: 'foundry-core', label: 'foundry/core', description: 'Design tokens and primitives' },
  { value: 'foundry-blocks', label: 'foundry/blocks', description: 'Sections and navigation' },
  { value: 'foundry-docs', label: 'foundry/docs', description: 'Documentation site' },
  { value: 'foundry-cli', label: 'foundry/cli', description: 'Component scaffolding' },
  { value: 'acme-platform', label: 'acme/platform', description: 'Product monorepo' },
  { value: 'acme-infra', label: 'acme/infra', description: 'Terraform modules' },
  {
    value: 'acme-legacy',
    label: 'acme/legacy',
    description: 'Archived — read only',
    disabled: true,
  },
]

export default function ComboboxDemo() {
  const [value, setValue] = useState('foundry-blocks')

  return (
    <DemoStage>
      <DemoColumn>
        <Field
          name="repository"
          label="Repository"
          hint="Type to filter. Arrow keys browse without leaving the input."
          required
        >
          {(field) => (
            <Combobox
              id={field.id}
              name={field.name}
              aria-describedby={field['aria-describedby']}
              options={repositories}
              value={value}
              onValueChange={setValue}
              placeholder="Search repositories"
            />
          )}
        </Field>

        <Field name="mirror" label="Mirror target" error="Choose a repository to mirror into.">
          {(field) => (
            <Combobox
              id={field.id}
              name={field.name}
              aria-describedby={field['aria-describedby']}
              invalid
              options={repositories}
              placeholder="Search repositories"
              emptyMessage="No repository matches that name."
            />
          )}
        </Field>

        <p className="text-xs text-ink-muted">
          Selected value: <code className="font-mono text-ink">{value}</code>
        </p>
      </DemoColumn>
    </DemoStage>
  )
}

'use client'

import { useMemo, useRef, useState, type KeyboardEvent } from 'react'
import { ChevronDown, Check, Search } from 'lucide-react'
import { cn } from '@/lib/cn'
import { useDismiss } from '@/hooks/use-dismiss'
import { controlSurface } from './input'

/**
 * Combobox
 *
 * Implements the ARIA 1.2 combobox pattern with a filterable listbox popup:
 * the text input owns `role="combobox"`, `aria-expanded` and
 * `aria-activedescendant`, and the list is a real `role="listbox"` whose
 * options carry `aria-selected`.
 *
 * Focus never leaves the input, which is what makes arrow-key browsing feel
 * right and keeps the on-screen keyboard open on mobile.
 */
export interface ComboboxOption {
  value: string
  label: string
  description?: string
  disabled?: boolean
}

export interface ComboboxProps {
  options: ComboboxOption[]
  id?: string
  name?: string
  value?: string
  defaultValue?: string
  placeholder?: string
  emptyMessage?: string
  disabled?: boolean
  invalid?: boolean
  className?: string
  'aria-describedby'?: string
  onValueChange?: (value: string) => void
}

export function Combobox({
  options,
  id = 'combobox',
  name,
  value: controlledValue,
  defaultValue = '',
  placeholder = 'Select an option',
  emptyMessage = 'No matches found.',
  disabled = false,
  invalid = false,
  className,
  onValueChange,
  ...aria
}: ComboboxProps) {
  const [open, setOpen] = useState(false)
  const [query, setQuery] = useState('')
  const [activeIndex, setActiveIndex] = useState(0)
  const [uncontrolled, setUncontrolled] = useState(defaultValue)
  const value = controlledValue ?? uncontrolled

  const rootRef = useRef<HTMLDivElement>(null)
  const inputRef = useRef<HTMLInputElement>(null)
  const listId = `${id}-listbox`

  const selected = options.find((option) => option.value === value)

  const filtered = useMemo(() => {
    const q = query.trim().toLowerCase()
    if (!q) return options
    return options.filter(
      (option) =>
        option.label.toLowerCase().includes(q) ||
        option.description?.toLowerCase().includes(q) ||
        option.value.toLowerCase().includes(q),
    )
  }, [options, query])

  useDismiss([rootRef], open, () => {
    setOpen(false)
    setQuery('')
  })

  const select = (option: ComboboxOption) => {
    if (option.disabled) return
    if (controlledValue === undefined) setUncontrolled(option.value)
    onValueChange?.(option.value)
    setOpen(false)
    setQuery('')
    inputRef.current?.focus()
  }

  const onKeyDown = (event: KeyboardEvent<HTMLInputElement>) => {
    if (event.key === 'ArrowDown' || event.key === 'ArrowUp') {
      event.preventDefault()
      if (!open) {
        setOpen(true)
        setActiveIndex(0)
        return
      }
      const direction = event.key === 'ArrowDown' ? 1 : -1
      setActiveIndex((current) => {
        if (filtered.length === 0) return 0
        return (current + direction + filtered.length) % filtered.length
      })
    } else if (event.key === 'Enter') {
      if (!open) return
      event.preventDefault()
      const option = filtered[activeIndex]
      if (option) select(option)
    } else if (event.key === 'Home' && open) {
      event.preventDefault()
      setActiveIndex(0)
    } else if (event.key === 'End' && open) {
      event.preventDefault()
      setActiveIndex(Math.max(0, filtered.length - 1))
    } else if (event.key === 'Tab') {
      setOpen(false)
    }
  }

  const activeOption = filtered[activeIndex]

  return (
    <div ref={rootRef} className={cn('relative', className)}>
      {name ? <input type="hidden" name={name} value={value} /> : null}
      <div className="relative flex items-center">
        <Search
          className="pointer-events-none absolute left-3 size-4 text-ink-subtle"
          aria-hidden="true"
        />
        <input
          ref={inputRef}
          id={id}
          role="combobox"
          type="text"
          autoComplete="off"
          disabled={disabled}
          aria-expanded={open}
          aria-controls={listId}
          aria-autocomplete="list"
          aria-activedescendant={
            open && activeOption ? `${id}-option-${activeOption.value}` : undefined
          }
          aria-invalid={invalid || undefined}
          aria-describedby={aria['aria-describedby']}
          placeholder={placeholder}
          value={open ? query : (selected?.label ?? '')}
          onChange={(event) => {
            setQuery(event.target.value)
            setActiveIndex(0)
            if (!open) setOpen(true)
          }}
          onFocus={() => setOpen(true)}
          onKeyDown={onKeyDown}
          className={cn(
            controlSurface,
            'h-control cursor-default pr-9 pl-9 text-sm',
            invalid && 'border-danger bg-danger-soft',
          )}
        />
        <button
          type="button"
          tabIndex={-1}
          aria-hidden="true"
          disabled={disabled}
          onClick={() => {
            setOpen((o) => !o)
            inputRef.current?.focus()
          }}
          className="absolute right-2 flex size-6 items-center justify-center rounded-sm text-ink-subtle"
        >
          <ChevronDown
            className={cn('size-4 transition-transform duration-150', open && 'rotate-180')}
          />
        </button>
      </div>

      {open ? (
        <ul
          id={listId}
          role="listbox"
          aria-label="Options"
          className="absolute z-50 mt-1 max-h-64 w-full overflow-y-auto rounded-md border border-line bg-surface-raised p-1 shadow-md thin-scrollbar"
        >
          {filtered.length === 0 ? (
            <li className="px-3 py-6 text-center text-sm text-ink-muted">{emptyMessage}</li>
          ) : (
            filtered.map((option, index) => (
              <li
                key={option.value}
                id={`${id}-option-${option.value}`}
                role="option"
                aria-selected={option.value === value}
                aria-disabled={option.disabled || undefined}
                onMouseEnter={() => setActiveIndex(index)}
                onPointerDown={(event) => {
                  event.preventDefault()
                  select(option)
                }}
                className={cn(
                  'flex cursor-pointer items-start gap-2 rounded-sm px-2.5 py-2 text-sm',
                  index === activeIndex && 'bg-surface-sunken',
                  option.disabled && 'cursor-not-allowed opacity-50',
                )}
              >
                <Check
                  className={cn(
                    'mt-0.5 size-4 shrink-0 text-accent',
                    option.value === value ? 'opacity-100' : 'opacity-0',
                  )}
                  aria-hidden="true"
                />
                <span className="min-w-0">
                  <span className="block truncate font-medium text-ink">{option.label}</span>
                  {option.description ? (
                    <span className="block truncate text-xs text-ink-muted">
                      {option.description}
                    </span>
                  ) : null}
                </span>
              </li>
            ))
          )}
        </ul>
      ) : null}
    </div>
  )
}

'use client'

import { useEffect, type RefObject } from 'react'

/**
 * Closes a layer on Escape or on a pointer press outside it.
 *
 * `pointerdown` is used rather than `click` so that dragging a text selection
 * out of a popover does not dismiss it, and Escape is captured on the document
 * so it works even when focus has moved into a nested portal.
 */
export function useDismiss(
  refs: Array<RefObject<HTMLElement | null>>,
  active: boolean,
  onDismiss: () => void,
  options: { escape?: boolean; outside?: boolean } = {},
): void {
  const { escape = true, outside = true } = options

  useEffect(() => {
    if (!active) return

    const onKeyDown = (event: KeyboardEvent) => {
      if (!escape) return
      if (event.key === 'Escape') {
        event.stopPropagation()
        onDismiss()
      }
    }

    const onPointerDown = (event: PointerEvent) => {
      if (!outside) return
      const target = event.target as Node | null
      if (!target) return
      const inside = refs.some((ref) => ref.current?.contains(target))
      if (!inside) onDismiss()
    }

    document.addEventListener('keydown', onKeyDown)
    document.addEventListener('pointerdown', onPointerDown)
    return () => {
      document.removeEventListener('keydown', onKeyDown)
      document.removeEventListener('pointerdown', onPointerDown)
    }
    // `refs` is a stable-length array supplied by the caller at each layer.
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [active, escape, outside, onDismiss])
}

/** Locks body scroll while a modal layer is open, without layout shift. */
export function useScrollLock(active: boolean): void {
  useEffect(() => {
    if (!active) return
    const { body, documentElement } = document
    const scrollBarWidth = window.innerWidth - documentElement.clientWidth
    const previousOverflow = body.style.overflow
    const previousPadding = body.style.paddingRight

    body.style.overflow = 'hidden'
    if (scrollBarWidth > 0) body.style.paddingRight = `${scrollBarWidth}px`

    return () => {
      body.style.overflow = previousOverflow
      body.style.paddingRight = previousPadding
    }
  }, [active])
}