<script lang="ts">
  import PostCard from "./PostCard.svelte";
  import Tag from "./Tag.svelte";
  import Pagination from "./Pagination.svelte";
  import Ico from "./Ico.svelte";
  import type { PostEntry } from "../lib/cms";
  import { postHref } from "../lib/blog-utils";
  import { t as tStatic, T } from "../lib/translations";
  import type { Translations } from "../lib/translations";

  interface TagEntry {
    _slug?: string;
    name: string;
    icon?: string;
    color?: string;
  }

  type SearchIndexEntry = {
    slug: string;
    headline: string;
    excerpt: string;
    subheadline: string;
    tags: string[];
    image: string | null;
    created: string | null;
    isEvent: boolean;
    eventDate: string | null;
  };

  type EventPost = PostEntry & { eventDate?: string; isEvent?: boolean };

  let {
    posts = [],
    tags = [],
    activeTag = null,
    currentPage = 1,
    totalPages = 1,
    totalPosts = 0,
    basePath = "/posts",
    translations = {},
    upcomingEvents = [],
    searchIndex = null,
  }: {
    posts: PostEntry[];
    tags: TagEntry[];
    activeTag: string | null;
    currentPage: number;
    totalPages: number;
    totalPosts?: number;
    basePath?: string;
    translations?: Translations | null;
    upcomingEvents?: EventPost[];
    searchIndex?: SearchIndexEntry[] | null;
  } = $props();

  let query = $state("");
  let year = $state<string>("");
  const normalizedQuery = $derived(query.trim().toLowerCase());
  const isFiltering = $derived(normalizedQuery.length >= 2 || year !== "");

  function yearOf(entry: SearchIndexEntry): string {
    const iso = entry.created ?? "";
    if (!iso) return "";
    const d = new Date(iso);
    return Number.isNaN(d.getTime()) ? "" : String(d.getFullYear());
  }

  const availableYears = $derived.by<string[]>(() => {
    if (!searchIndex) return [];
    const set = new Set<string>();
    for (const p of searchIndex) {
      const y = yearOf(p);
      if (y) set.add(y);
    }
    return Array.from(set).sort((a, b) => b.localeCompare(a));
  });

  const filteredResults = $derived.by<SearchIndexEntry[]>(() => {
    if (!isFiltering || !searchIndex) return [];
    const q = normalizedQuery;
    return searchIndex
      .filter((p) => {
        if (year && yearOf(p) !== year) return false;
        if (q) {
          const hay = `${p.headline} ${p.excerpt} ${p.subheadline} ${p.tags.join(" ")}`.toLowerCase();
          if (!hay.includes(q)) return false;
        }
        return true;
      })
      .slice(0, 80);
  });

  function searchResultHref(slug: string): string {
    const norm = (slug ?? "").replace(/^\//, "").trim();
    return norm ? `/post/${encodeURIComponent(norm)}` : "/post";
  }

  function formatEventDate(iso: string | null | undefined): string {
    if (!iso) return "";
    const d = new Date(iso);
    if (Number.isNaN(d.getTime())) return "";
    return d.toLocaleDateString("de-DE", { day: "2-digit", month: "long", year: "numeric" });
  }

  /** Immer Übersetzungen von der Astro-Seite nutzen (SSR + Insel), damit Keys wie blog_tag_all ankommen. */
  function t(key: string, replacements?: Record<string, string | number>) {
    return tStatic(translations ?? null, key, replacements);
  }

  function tagHref(tagSlug: string | null): string {
    if (!tagSlug) return basePath;
    return `${basePath}/tag/${encodeURIComponent(tagSlug)}`;
  }

  const totalCount = $derived(totalPosts);
</script>

<div class="blog-overview">
  {#if searchIndex}
    <div class="mb-4 flex flex-wrap items-center gap-2">
      <label class="relative block w-full sm:max-w-sm">
        <span class="sr-only">Suche</span>
        <span class="pointer-events-none absolute top-1/2 left-2 -translate-y-1/2 text-zinc-500">
          <Ico icon="mdi:magnify" class="h-4 w-4" />
        </span>
        <input
          type="search"
          bind:value={query}
          placeholder="Beiträge durchsuchen…"
          class="w-full rounded-sm border border-zinc-300 bg-white py-2 pr-9 pl-8 text-sm focus:border-zinc-500 focus:outline-none"
        />
        {#if query}
          <button
            type="button"
            onclick={() => (query = "")}
            class="absolute top-1/2 right-1.5 -translate-y-1/2 rounded-sm p-1 text-zinc-500 hover:bg-zinc-100 hover:text-zinc-900"
            aria-label="Suche leeren"
          >
            <Ico icon="mdi:close" class="h-4 w-4" />
          </button>
        {/if}
      </label>
      {#if availableYears.length > 0}
        <label class="relative inline-flex items-center">
          <span class="sr-only">Jahr</span>
          <span class="pointer-events-none absolute top-1/2 left-2 -translate-y-1/2 text-zinc-500">
            <Ico icon="mdi:calendar" class="h-4 w-4" />
          </span>
          <select
            bind:value={year}
            class="appearance-none rounded-sm border border-zinc-300 bg-white py-2 pr-7 pl-8 text-sm focus:border-zinc-500 focus:outline-none"
          >
            <option value="">Alle Jahre</option>
            {#each availableYears as y}
              <option value={y}>{y}</option>
            {/each}
          </select>
          <span class="pointer-events-none absolute top-1/2 right-1.5 -translate-y-1/2 text-zinc-500">
            <Ico icon="mdi:chevron-down" class="h-4 w-4" />
          </span>
        </label>
      {/if}
    </div>
  {/if}

  {#if !isFiltering && upcomingEvents.length > 0}
    <section class="mb-6 rounded-sm border border-zinc-200 bg-zinc-50 p-4">
      <h2 class="mb-3 flex items-center gap-1.5 text-sm font-semibold tracking-wide text-zinc-700 uppercase">
        <Ico icon="mdi:calendar-clock" class="h-4 w-4" />
        Nächste Termine
      </h2>
      <ul class="space-y-2">
        {#each upcomingEvents as ev}
          <li>
            <a href={postHref(ev)} class="group flex items-baseline gap-3 no-underline hover:underline">
              <time class="shrink-0 text-xs font-medium text-zinc-600 tabular-nums">
                {formatEventDate(ev.eventDate)}
              </time>
              <span class="text-sm text-zinc-900 group-hover:text-zinc-950">{ev.headline}</span>
            </a>
          </li>
        {/each}
      </ul>
    </section>
  {/if}

  {#if isFiltering}
    <div class="mb-3 flex flex-wrap items-center gap-2 text-xs text-zinc-600">
      <span>
        {filteredResults.length}
        {filteredResults.length === 1 ? "Treffer" : "Treffer"}
        {#if query}für „{query}"{/if}
        {#if year}im Jahr {year}{/if}
      </span>
      <button
        type="button"
        onclick={() => { query = ""; year = ""; }}
        class="text-zinc-500 underline hover:text-zinc-900"
      >Filter zurücksetzen</button>
    </div>
    {#if filteredResults.length > 0}
      <div class="py-2 grid grid-cols-1 gap-4 sm:grid-cols-2 lg:grid-cols-3">
        {#each filteredResults as hit}
          <a href={searchResultHref(hit.slug)} class="flex flex-col overflow-hidden border border-gray-200 bg-white text-slate-950 no-underline transition-all">
            {#if hit.image}
              <div class="aspect-3/2 w-full overflow-hidden bg-gray-100">
                <img src={hit.image} alt={hit.headline} class="h-full w-full object-cover" loading="lazy" />
              </div>
            {/if}
            <div class="flex flex-1 flex-col p-4">
              <h3 class="mb-1 text-base font-semibold">{hit.headline}</h3>
              {#if hit.excerpt}
                <p class="text-sm text-zinc-700 line-clamp-3">{hit.excerpt}</p>
              {/if}
            </div>
          </a>
        {/each}
      </div>
    {:else}
      <div class="rounded-sm border border-zinc-200 bg-white p-6 text-center text-sm text-zinc-600">
        Keine Treffer. Versuche einen anderen Suchbegriff.
      </div>
    {/if}
  {:else}
  {#if tags.length > 0}
    <div class="mb-2">
      <div class="flex flex-wrap gap-2" role="navigation" aria-label={t(T.blog_filter_aria)}>
        <Tag
          label={t(T.blog_tag_all)}
          href={tagHref(null)}
          variant={activeTag ? "blue" : "green"}
          active={!activeTag}
        />
        {#each tags as tag}
          {@const slug = tag._slug ?? ""}
          <Tag
            label={tag.name}
            href={tagHref(slug)}
            variant={activeTag === slug ? "inactive" : "green"}
            active={activeTag === slug}
            icon={tag.icon?.trim() || null}
            customColor={activeTag === slug ? null : tag.color?.trim() || null}
          />
        {/each}
      </div>
    </div>
  {/if}

  <Pagination
    {currentPage}
    {totalPages}
    {basePath}
    activeTag={activeTag}
  />

  <div class="py-2 grid grid-cols-1 gap-4 sm:grid-cols-2 lg:grid-cols-3">
    {#each posts as post}
      <PostCard
        post={post}
        href={postHref(post)}
        tagBase={`${basePath}/tag`}
      />
    {/each}
  </div>

  <div class="flex flex-wrap items-center gap-2">
    <Pagination
      {currentPage}
      {totalPages}
      {basePath}
      activeTag={activeTag}
    />
    <div class="grow"></div>
    <div class="bg-white rounded-md font-thin">
      <div class="inline-flex text-xs p-2">
        {#if totalCount > 0}
          {t(T.blog_count, {
            visible: posts.length,
            total: totalCount,
            current: currentPage,
            totalPages,
          })}
        {:else}
          {t(T.blog_count, {
            visible: 0,
            total: 0,
            current: currentPage,
            totalPages,
          })}
        {/if}
      </div>
    </div>
  </div>

  <div class="mt-4 text-xs text-zinc-600">
    <a href="/posts/rss.xml" class="inline-flex items-center gap-1 hover:underline">
      <Ico icon="mdi:rss" class="h-3.5 w-3.5" />
      RSS-Feed abonnieren
    </a>
  </div>
  {/if}
</div>
