'use client';

import { useState } from 'react';
import { Check, ChevronsUpDown } from 'lucide-react';
import { useQuery } from '@tanstack/react-query';

import { Button } from '@/components/ui/button';
import {
  Command,
  CommandEmpty,
  CommandGroup,
  CommandInput,
  CommandItem,
  CommandList,
} from '@/components/ui/command';
import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
import { useDebounce } from '@/hooks/use-debounce';
import { apiFetch } from '@/lib/api/client';
import { cn } from '@/lib/utils';

interface ClientOption {
  id: string;
  fullName: string;
}

interface ClientPickerProps {
  value: string | null;
  onChange: (clientId: string | null) => void;
  placeholder?: string;
  disabled?: boolean;
}

export function ClientPicker({
  value,
  onChange,
  placeholder = 'Select client...',
  disabled,
}: ClientPickerProps) {
  const [open, setOpen] = useState(false);
  const [search, setSearch] = useState('');
  const debounced = useDebounce(search, 300);

  const { data } = useQuery<{ data: ClientOption[] }>({
    queryKey: ['client-picker', debounced],
    queryFn: () =>
      apiFetch(
        `/api/v1/clients?search=${encodeURIComponent(debounced)}&page=1&limit=10&order=desc&includeArchived=false`,
      ),
    enabled: open,
  });

  // The search results are paginated and only fetched while the popover
  // is open, so a `value` set from outside (e.g. an existing reservation)
  // can't be name-resolved from them. A second query targets the picked
  // client directly so the trigger label reads as the rep's name, not a
  // UUID-prefix fallback.
  const { data: selectedData } = useQuery<{ data: { id: string; fullName: string } }>({
    queryKey: ['client-picker', 'selected', value],
    queryFn: () => apiFetch(`/api/v1/clients/${value}`),
    enabled: !!value,
    staleTime: 5 * 60_000,
  });

  const options = data?.data ?? [];

  const selectedLabel = (() => {
    if (!value) return placeholder;
    const match = options.find((o) => o.id === value);
    return match?.fullName ?? selectedData?.data?.fullName ?? `Client ${value.slice(0, 8)}`;
  })();

  return (
    // `modal` is required when this picker is rendered inside a Sheet /
    // Dialog - without it the CommandInput stays focus-blocked by the
    // outer Sheet's focus trap and clicks/typing are silently dropped.
    <Popover open={open} onOpenChange={setOpen} modal>
      <PopoverTrigger asChild>
        <Button
          variant="outline"
          role="combobox"
          disabled={disabled}
          className={cn('w-full justify-between', !value && 'text-muted-foreground')}
        >
          <span className="truncate">{selectedLabel}</span>
          <ChevronsUpDown className="ml-2 h-4 w-4 shrink-0 opacity-50" aria-hidden />
        </Button>
      </PopoverTrigger>
      <PopoverContent className="w-[320px] p-0" align="start">
        <Command shouldFilter={false}>
          <CommandInput placeholder="Search clients…" value={search} onValueChange={setSearch} />
          <CommandList>
            <CommandEmpty>No clients found.</CommandEmpty>
            <CommandGroup>
              {value ? (
                <CommandItem
                  value="__clear__"
                  onSelect={() => {
                    onChange(null);
                    setOpen(false);
                  }}
                  className="text-muted-foreground"
                >
                  Clear selection
                </CommandItem>
              ) : null}
              {options.map((c) => (
                <CommandItem
                  key={c.id}
                  value={c.id}
                  onSelect={() => {
                    onChange(c.id);
                    setOpen(false);
                  }}
                >
                  <Check
                    className={cn('mr-2 h-4 w-4', value === c.id ? 'opacity-100' : 'opacity-0')}
                  />
                  <span>{c.fullName}</span>
                </CommandItem>
              ))}
            </CommandGroup>
          </CommandList>
        </Command>
      </PopoverContent>
    </Popover>
  );
}