"use client";

import Link from "next/link";
import { SearchIcon, SparklesIcon, XIcon } from "lucide-react";
import { useMemo, useState } from "react";

import { MediaImage } from "@/components/public/media-image";
import { Badge } from "@/components/ui/badge";
import { Button } from "@/components/ui/button";
import {
  Card,
  CardAction,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";
import {
  Empty,
  EmptyContent,
  EmptyDescription,
  EmptyHeader,
  EmptyMedia,
  EmptyTitle,
} from "@/components/ui/empty";
import {
  InputGroup,
  InputGroupAddon,
  InputGroupInput,
} from "@/components/ui/input-group";
import type { PublicCharacterCard } from "@/lib/content/types";
import { cn } from "@/lib/utils";

interface CharacterDirectoryProps {
  characters: PublicCharacterCard[];
}

function unique(values: Array<string | null>): string[] {
  return [...new Set(values.filter((value): value is string => Boolean(value)))];
}

export function CharacterDirectory({ characters }: CharacterDirectoryProps) {
  const [query, setQuery] = useState("");
  const [element, setElement] = useState<string | null>(null);
  const [role, setRole] = useState<string | null>(null);
  const elements = useMemo(
    () => unique(characters.map((character) => character.element)),
    [characters],
  );
  const roles = useMemo(
    () => unique(characters.map((character) => character.role)),
    [characters],
  );
  const normalizedQuery = query.trim().toLocaleLowerCase("th");
  const filtered = characters.filter((character) => {
    const searchable = `${character.nameTh} ${character.nameEn ?? ""}`.toLocaleLowerCase("th");
    return (
      (!normalizedQuery || searchable.includes(normalizedQuery)) &&
      (!element || character.element === element) &&
      (!role || character.role === role)
    );
  });
  const hasFilters = Boolean(query || element || role);

  return (
    <div className="space-y-8">
      <div className="space-y-4">
        <InputGroup className="h-11 max-w-2xl bg-card">
          <InputGroupAddon>
            <SearchIcon aria-hidden="true" />
          </InputGroupAddon>
          <InputGroupInput
            value={query}
            onChange={(event) => setQuery(event.target.value)}
            placeholder="ค้นหาชื่อตัวละคร…"
            aria-label="ค้นหาตัวละคร"
          />
          {query ? (
            <InputGroupAddon align="inline-end">
              <Button
                type="button"
                variant="ghost"
                size="icon-sm"
                aria-label="ล้างคำค้นหา"
                onClick={() => setQuery("")}
              >
                <XIcon aria-hidden="true" />
              </Button>
            </InputGroupAddon>
          ) : null}
        </InputGroup>

        <div className="flex flex-wrap gap-x-5 gap-y-3 text-sm">
          {elements.length > 0 ? (
            <FilterGroup
              label="ธาตุ"
              values={elements}
              selected={element}
              onChange={setElement}
            />
          ) : null}
          {roles.length > 0 ? (
            <FilterGroup
              label="บทบาท"
              values={roles}
              selected={role}
              onChange={setRole}
            />
          ) : null}
        </div>
      </div>

      {filtered.length > 0 ? (
        <div
          className="grid grid-cols-1 gap-4 sm:grid-cols-2 lg:grid-cols-3 xl:grid-cols-4"
          aria-live="polite"
        >
          {filtered.map((character) => (
            <Link
              key={character.id}
              href={`/${character.slug}/${character.firstPageSlug}`}
              className="group rounded-xl focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring"
            >
              <Card className="h-full gap-0 py-0 transition-transform group-hover:-translate-y-0.5 group-focus-visible:ring-2 group-focus-visible:ring-ring">
                <MediaImage
                  mediaId={character.portraitMediaId}
                  alt={`ภาพ ${character.nameTh}`}
                  className="aspect-4/3 min-h-0 rounded-t-xl"
                />
                <CardHeader className="pt-4">
                  <CardTitle className="text-lg">{character.nameTh}</CardTitle>
                  <CardDescription>{character.nameEn ?? "คู่มือตัวละคร"}</CardDescription>
                  {character.rarity ? (
                    <CardAction>
                      <Badge variant="secondary">{character.rarity}★</Badge>
                    </CardAction>
                  ) : null}
                </CardHeader>
                <CardContent className="flex flex-wrap gap-2 pb-4">
                  {character.element ? <Badge>{character.element}</Badge> : null}
                  {character.role ? (
                    <Badge variant="outline">{character.role}</Badge>
                  ) : null}
                </CardContent>
              </Card>
            </Link>
          ))}
        </div>
      ) : (
        <Empty className="border bg-card/40" aria-live="polite">
          <EmptyHeader>
            <EmptyMedia variant="icon">
              <SparklesIcon aria-hidden="true" />
            </EmptyMedia>
            <EmptyTitle>ไม่พบตัวละครที่ตรงกัน</EmptyTitle>
            <EmptyDescription>
              ลองใช้ชื่ออื่นหรือเอาตัวกรองบางรายการออก
            </EmptyDescription>
          </EmptyHeader>
          {hasFilters ? (
            <EmptyContent>
              <Button
                type="button"
                variant="outline"
                onClick={() => {
                  setQuery("");
                  setElement(null);
                  setRole(null);
                }}
              >
                ล้างตัวกรอง
              </Button>
            </EmptyContent>
          ) : null}
        </Empty>
      )}
    </div>
  );
}

function FilterGroup({
  label,
  values,
  selected,
  onChange,
}: {
  label: string;
  values: string[];
  selected: string | null;
  onChange: (value: string | null) => void;
}) {
  return (
    <div className="flex flex-wrap items-center gap-2" role="group" aria-label={label}>
      <span className="text-muted-foreground">{label}</span>
      {values.map((value) => (
        <Button
          key={value}
          type="button"
          size="xs"
          variant={selected === value ? "secondary" : "ghost"}
          aria-pressed={selected === value}
          className={cn(selected === value && "text-primary")}
          onClick={() => onChange(selected === value ? null : value)}
        >
          {value}
        </Button>
      ))}
    </div>
  );
}