"use client";

import { ArrowDownUpIcon, RefreshCwIcon, SearchIcon, XIcon } from "lucide-react";
import { useEffect, useRef, useState } from "react";
import { Button } from "@/components/ui/button";
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuGroup,
  DropdownMenuLabel,
  DropdownMenuRadioGroup,
  DropdownMenuRadioItem,
  DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu";
import { Input } from "@/components/ui/input";
import { ToggleGroup, ToggleGroupItem } from "@/components/ui/toggle-group";
import type { Range, Sort } from "@/lib/filter";
import { cn } from "@/lib/utils";

const RANGE_LABELS: Record<Range, string> = { future: "Kommend", past: "Vergangen", all: "Alle" };
const SORT_LABELS: Record<Sort, string> = {
  start_asc: "Beginn – früheste zuerst",
  start_desc: "Beginn – späteste zuerst",
  created_asc: "Erstellt – älteste zuerst",
  created_desc: "Erstellt – neueste zuerst",
};

/**
 * Search, sort, reload and the time range. The search box keeps its own text
 * and writes it to the URL after a short pause, so typing doesn't replace the
 * URL on every keystroke.
 */
export function EventsToolbar({
  query,
  range,
  sort,
  loading,
  onQueryChange,
  onRangeChange,
  onSortChange,
  onReload,
}: {
  query: string;
  range: Range;
  sort: Sort;
  loading: boolean;
  onQueryChange: (query: string) => void;
  onRangeChange: (range: Range) => void;
  onSortChange: (sort: Sort) => void;
  onReload: () => void;
}) {
  const [text, setText] = useState(query);
  // Take over a query that changed from outside (the empty state's "Suche
  // leeren", the back button) - but not our own write coming back through the
  // URL, which would drop whatever was typed while it travelled.
  const [seenQuery, setSeenQuery] = useState(query);
  const [emitted, setEmitted] = useState(query);
  if (query !== seenQuery) {
    setSeenQuery(query);
    if (query !== emitted) {
      setText(query);
    }
  }

  const onQueryChangeRef = useRef(onQueryChange);
  useEffect(() => {
    onQueryChangeRef.current = onQueryChange;
  });

  useEffect(() => {
    if (text === query) return;
    const timer = setTimeout(() => {
      setEmitted(text);
      onQueryChangeRef.current(text);
    }, 250);
    return () => clearTimeout(timer);
  }, [text, query]);

  return (
    <div className="flex flex-col gap-3">
      <div className="flex items-center gap-2">
        <div className="relative flex-1">
          <SearchIcon aria-hidden className="pointer-events-none absolute top-1/2 left-3 size-4 -translate-y-1/2 text-muted-foreground" />
          <Input
            type="search"
            value={text}
            onChange={(e) => setText(e.target.value)}
            placeholder="Titel oder Ort suchen"
            aria-label="Termine durchsuchen"
            className="pr-9 pl-9 [&::-webkit-search-cancel-button]:hidden"
          />
          {text !== "" && (
            <button
              type="button"
              onClick={() => {
                setText("");
                onQueryChange("");
              }}
              aria-label="Suche leeren"
              className="absolute top-1/2 right-2 flex size-6 -translate-y-1/2 items-center justify-center rounded-full text-muted-foreground hover:bg-muted"
            >
              <XIcon className="size-3.5" />
            </button>
          )}
        </div>

        <DropdownMenu>
          <DropdownMenuTrigger render={<Button variant="outline" size="icon" aria-label="Sortierung" />}>
            <ArrowDownUpIcon />
          </DropdownMenuTrigger>
          <DropdownMenuContent align="end" className="w-60">
            <DropdownMenuGroup>
              <DropdownMenuLabel>Sortieren nach</DropdownMenuLabel>
              <DropdownMenuRadioGroup value={sort} onValueChange={(value) => onSortChange(value as Sort)}>
                {(Object.keys(SORT_LABELS) as Sort[]).map((key) => (
                  // Base UI keeps a menu open after a radio pick by default; one choice is all there is here.
                  <DropdownMenuRadioItem key={key} value={key} closeOnClick>
                    {SORT_LABELS[key]}
                  </DropdownMenuRadioItem>
                ))}
              </DropdownMenuRadioGroup>
            </DropdownMenuGroup>
          </DropdownMenuContent>
        </DropdownMenu>

        <Button variant="outline" size="icon" onClick={onReload} aria-label="Neu laden" disabled={loading}>
          <RefreshCwIcon className={cn(loading && "animate-spin")} />
        </Button>
      </div>

      <ToggleGroup
        value={[range]}
        onValueChange={(value) => {
          // A segmented control: clicking the pressed item must not leave nothing selected.
          const next = value[0] as Range | undefined;
          if (next) onRangeChange(next);
        }}
        variant="outline"
        spacing={0}
        className="grid w-full grid-cols-3 sm:inline-grid sm:w-auto"
        aria-label="Zeitraum"
      >
        {(Object.keys(RANGE_LABELS) as Range[]).map((key) => (
          <ToggleGroupItem key={key} value={key} className="aria-pressed:bg-foreground/[0.06] aria-pressed:font-semibold">
            {RANGE_LABELS[key]}
          </ToggleGroupItem>
        ))}
      </ToggleGroup>
    </div>
  );
}