AI_Translator/apps/web/components/LanguageSelect.tsx

'use client'

import { useEffect, useMemo, useRef, useState } from 'react'
import { ChevronDown, Search, X } from 'lucide-react'

import { cn } from '@/lib/utils'
import { Badge } from '@/components/ui/badge'
import { Button } from '@/components/ui/button'
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card'
import { Input } from '@/components/ui/input'
import type { LanguageOption } from '@/lib/languages'

type Props = {
  value: string
  onValueChange: (value: string) => void
  options: LanguageOption[]
  commonOptions?: LanguageOption[]
  placeholder?: string
  searchPlaceholder?: string
  disabled?: boolean
  allowAuto?: boolean
  autoOption?: LanguageOption
  triggerClassName?: string
}

export default function LanguageSelect({
  value,
  onValueChange,
  options,
  commonOptions,
  placeholder = '选择语言',
  searchPlaceholder = '搜索语言（名称 / 代码）',
  disabled,
  allowAuto,
  autoOption,
  triggerClassName,
}: Props) {
  const [open, setOpen] = useState(false)
  const [query, setQuery] = useState('')
  const inputRef = useRef<HTMLInputElement | null>(null)

  const allOptions = useMemo(() => {
    const list = [...options]
    if (allowAuto && autoOption) {
      return [autoOption, ...list]
    }
    return list
  }, [allowAuto, autoOption, options])

  const selected = useMemo(() => {
    return allOptions.find((o) => o.code === value) || null
  }, [allOptions, value])

  const filtered = useMemo(() => {
    const q = query.trim().toLowerCase()
    if (!q) return allOptions
    return allOptions.filter((o) => (o.search || `${o.name} ${o.code}`).toLowerCase().includes(q))
  }, [allOptions, query])

  useEffect(() => {
    if (!open) return
    setQuery('')
    const id = window.setTimeout(() => inputRef.current?.focus(), 0)
    return () => window.clearTimeout(id)
  }, [open])

  useEffect(() => {
    if (!open) return
    const onKeyDown = (e: KeyboardEvent) => {
      if (e.key === 'Escape') setOpen(false)
    }
    window.addEventListener('keydown', onKeyDown)
    return () => window.removeEventListener('keydown', onKeyDown)
  }, [open])

  const handleSelect = (code: string) => {
    onValueChange(code)
    setOpen(false)
  }

  return (
    <>
      <button
        type="button"
        disabled={disabled}
        onClick={() => setOpen(true)}
        className={cn(
          'flex h-10 w-full items-center justify-between rounded-md border border-input bg-background px-3 py-2 text-sm ring-offset-background transition-colors',
          'focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2',
          'disabled:cursor-not-allowed disabled:opacity-50',
          triggerClassName
        )}
      >
        <span className={cn('line-clamp-1', selected ? 'text-foreground' : 'text-muted-foreground')}>
          {selected?.name || placeholder}
        </span>
        <ChevronDown className="h-4 w-4 opacity-50" />
      </button>

      {open && (
        <div
          className="fixed inset-0 z-50 flex items-center justify-center bg-background/80 backdrop-blur-sm p-4"
          onMouseDown={(e) => {
            if (e.target === e.currentTarget) setOpen(false)
          }}
        >
          <Card className="w-full max-w-3xl border-muted shadow-lg">
            <CardHeader className="space-y-3">
              <div className="flex items-start justify-between gap-4">
                <div>
                  <CardTitle>选择语言</CardTitle>
                  <CardDescription>支持 200+ 语言，支持搜索</CardDescription>
                </div>
                <Button variant="ghost" size="icon" onClick={() => setOpen(false)}>
                  <X className="h-4 w-4" />
                </Button>
              </div>

              <div className="flex items-center gap-2">
                <div className="relative flex-1">
                  <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 text-muted-foreground" />
                  <Input
                    ref={inputRef}
                    value={query}
                    onChange={(e) => setQuery(e.target.value)}
                    placeholder={searchPlaceholder}
                    className="pl-9"
                  />
                </div>
                {query && (
                  <Button variant="outline" onClick={() => setQuery('')}>
                    清空
                  </Button>
                )}
              </div>

              {!query.trim() && commonOptions && commonOptions.length > 0 && (
                <div className="flex flex-wrap gap-2">
                  {commonOptions.map((o) => (
                    <button
                      key={o.code}
                      type="button"
                      onClick={() => handleSelect(o.code)}
                      className={cn(
                        'rounded-full border px-3 py-1 text-sm transition-colors',
                        o.code === value
                          ? 'bg-primary text-primary-foreground border-transparent'
                          : 'hover:bg-accent hover:text-accent-foreground'
                      )}
                    >
                      {o.name}
                    </button>
                  ))}
                </div>
              )}
            </CardHeader>

            <CardContent>
              <div className="rounded-md border bg-background max-h-[60vh] overflow-y-auto">
                {filtered.length === 0 ? (
                  <div className="p-6 text-center text-sm text-muted-foreground">无匹配语言</div>
                ) : (
                  <div className="divide-y">
                    {filtered.map((o) => (
                      <button
                        key={o.code}
                        type="button"
                        onClick={() => handleSelect(o.code)}
                        className={cn(
                          'w-full text-left px-4 py-3 hover:bg-accent transition-colors',
                          'flex items-center justify-between gap-4'
                        )}
                      >
                        <div className="min-w-0">
                          <div className="font-medium truncate">{o.name}</div>
                          <div className="text-xs text-muted-foreground font-mono">{o.code}</div>
                        </div>
                        <div className="shrink-0">
                          {o.code === value ? (
                            <Badge variant="success">已选</Badge>
                          ) : (
                            <Badge variant="outline" className="text-muted-foreground">
                              选择
                            </Badge>
                          )}
                        </div>
                      </button>
                    ))}
                  </div>
                )}
              </div>
            </CardContent>
          </Card>
        </div>
      )}
    </>
  )
}