import { useState, useEffect } from 'react'
import { useQuery } from '@tanstack/react-query'
import { api } from '../../../../api/client'

const PAGE_SIZE = 24

export default function ImagePicker({ open, onClose, onSelect, currentImageId }) {
  const [page, setPage] = useState(1)
  const [search, setSearch] = useState('')
  const [debouncedSearch, setDebouncedSearch] = useState('')

  useEffect(() => {
    const t = setTimeout(() => {
      setDebouncedSearch(search)
      setPage(1)
    }, 300)
    return () => clearTimeout(t)
  }, [search])

  useEffect(() => {
    if (!open) {
      setSearch('')
      setDebouncedSearch('')
      setPage(1)
    }
  }, [open])

  const { data, isLoading } = useQuery({
    queryKey: ['admin', 'images', { page, search: debouncedSearch }],
    queryFn: () => {
      const params = new URLSearchParams({
        page,
        limit: PAGE_SIZE,
        ...(debouncedSearch && { search: debouncedSearch }),
      })
      return api(`/api/admin/images?${params}`)
    },
    enabled: open,
    placeholderData: (prev) => prev,
  })

  const images = data?.items || []
  const totalPages = data?.total_pages || 1

  if (!open) return null

  return (
    <div
      className="fixed inset-0 z-50 flex items-center justify-center p-4 backdrop-blur-sm"
      style={{ background: 'var(--dialog-backdrop)' }}
      onClick={onClose}
    >
      <div
        className="w-full max-w-3xl rounded-2xl border shadow-2xl max-h-[90vh] flex flex-col"
        style={{
          backgroundImage: 'linear-gradient(to bottom, var(--dialog-bg-from), var(--dialog-bg-to))',
          borderColor: 'var(--dialog-border)',
        }}
        onClick={(e) => e.stopPropagation()}
      >
        <div
          className="px-6 py-4 border-b flex items-center justify-between shrink-0"
          style={{ borderColor: 'var(--panel-border)' }}
        >
          <h3 className="font-semibold" style={{ color: 'var(--text-strong)' }}>이미지 선택</h3>
          <button
            onClick={onClose}
            className="text-xl leading-none hover:bg-[var(--row-hover-bg)] w-7 h-7 rounded flex items-center justify-center"
            style={{ color: 'var(--text-dim)' }}
          >
            ×
          </button>
        </div>

        {/* 검색 */}
        <div className="px-6 pt-4 shrink-0">
          <div className="relative">
            <input
              type="text"
              value={search}
              onChange={(e) => setSearch(e.target.value)}
              placeholder="이미지 이름으로 검색..."
              className="w-full rounded-lg border pl-10 pr-4 py-2.5 text-sm outline-none focus:border-[var(--input-border-focus)] hover:border-[var(--input-border-hover)]"
              style={{
                background: 'var(--input-bg)',
                borderColor: 'var(--input-border)',
                color: 'var(--text-strong)',
              }}
            />
            <span className="absolute left-3 top-1/2 -translate-y-1/2" style={{ color: 'var(--input-icon)' }}>🔍</span>
          </div>
        </div>

        {/* 이미지 그리드 */}
        <div className="px-6 py-4 overflow-y-auto flex-1">
          {isLoading ? (
            <div className="grid gap-3 grid-cols-3 sm:grid-cols-4 lg:grid-cols-6">
              {Array.from({ length: 12 }).map((_, i) => (
                <div
                  key={i}
                  className="aspect-square rounded-lg animate-pulse"
                  style={{ background: 'var(--skeleton-bg)' }}
                />
              ))}
            </div>
          ) : images.length === 0 ? (
            <div className="py-12 text-center text-sm" style={{ color: 'var(--text-dim)' }}>
              {debouncedSearch ? '검색 결과가 없습니다' : '업로드된 이미지가 없습니다'}
            </div>
          ) : (
            <div className="grid gap-3 grid-cols-3 sm:grid-cols-4 lg:grid-cols-6">
              {images.map((image) => {
                const isSelected = currentImageId === image.id
                return (
                  <button
                    key={image.id}
                    type="button"
                    onClick={() => { onSelect(image); onClose() }}
                    className="group rounded-lg border overflow-hidden"
                    style={{
                      borderColor: isSelected ? 'var(--selected-border)' : 'var(--panel-border)',
                      boxShadow: isSelected ? '0 0 0 2px var(--ring-info)' : undefined,
                    }}
                    title={image.name}
                  >
                    <div
                      className="aspect-square flex items-center justify-center p-3"
                      style={{ backgroundImage: 'linear-gradient(to bottom right, var(--icon-box-from), var(--icon-box-to))' }}
                    >
                      <img src={image.url} alt={image.name} className="max-w-full max-h-full object-contain" />
                    </div>
                    <div
                      className="px-2 py-1.5 border-t"
                      style={{
                        borderColor: 'var(--panel-border)',
                        background: 'var(--surface-3)',
                      }}
                    >
                      <div className="text-xs truncate">{image.name}</div>
                    </div>
                  </button>
                )
              })}
            </div>
          )}
        </div>

        {/* 페이지네이션 + 액션 */}
        <div
          className="px-6 py-4 border-t flex items-center justify-between shrink-0 gap-3"
          style={{ borderColor: 'var(--panel-border)' }}
        >
          {totalPages > 1 ? (
            <div className="flex items-center gap-1">
              <button
                onClick={() => setPage((p) => Math.max(1, p - 1))}
                disabled={page === 1}
                className="w-8 h-8 rounded border hover:bg-[var(--btn-bg-hover)] disabled:opacity-30 disabled:cursor-not-allowed flex items-center justify-center text-sm"
                style={{
                  background: 'var(--btn-bg)',
                  borderColor: 'var(--btn-border)',
                  color: 'var(--text-emphasis)',
                }}
              >
                ‹
              </button>
              <span className="text-xs px-2" style={{ color: 'var(--text-muted)' }}>{page} / {totalPages}</span>
              <button
                onClick={() => setPage((p) => Math.min(totalPages, p + 1))}
                disabled={page === totalPages}
                className="w-8 h-8 rounded border hover:bg-[var(--btn-bg-hover)] disabled:opacity-30 disabled:cursor-not-allowed flex items-center justify-center text-sm"
                style={{
                  background: 'var(--btn-bg)',
                  borderColor: 'var(--btn-border)',
                  color: 'var(--text-emphasis)',
                }}
              >
                ›
              </button>
            </div>
          ) : <div />}

          {currentImageId && (
            <button
              type="button"
              onClick={() => { onSelect(null); onClose() }}
              className="text-sm hover:text-[var(--danger-text-strong)]"
              style={{ color: 'var(--danger-text)' }}
            >
              이미지 제거
            </button>
          )}
        </div>
      </div>
    </div>
  )
}