<script lang="ts">
  import type { AniListAuthorisation } from '$lib/Data/AniList/identity';
  import { prequels, type MediaPrequel } from '$lib/Data/AniList/prequels';
  import { onMount } from 'svelte';
  import { clearAllParameters, parseOrDefault } from '../../Utility/parameters';
  import { page } from '$app/stores';
  import { browser } from '$app/environment';
  import { season as getSeason } from '$lib/Media/Anime/season';
  import Skeleton from '$lib/Loading/Skeleton.svelte';
  import identity from '$stores/identity';
  import LogInRestricted from '$lib/Error/LogInRestricted.svelte';
  import Prequels from './Prequels.svelte';

  export let user: AniListAuthorisation;

  let currentPrequels: Promise<MediaPrequel[]> = Promise.resolve([]) as Promise<MediaPrequel[]>;
  const urlParameters = browser ? new URLSearchParams(window.location.search) : null;
  let year = parseOrDefault(urlParameters, 'year', new Date().getFullYear());
  let season = parseOrDefault(urlParameters, 'season', getSeason());

  $: {
    if (year.toString().length === 4 && $identity.id !== -2 && user)
      currentPrequels = prequels(user, year, season);
  }
  $: {
    if (browser) {
      $page.url.searchParams.set('year', year.toString());
      $page.url.searchParams.set('season', season.toString());
      clearAllParameters(['year', 'season']);
      history.replaceState(null, '', `?${$page.url.searchParams.toString()}`);
    }
  }

  onMount(() => clearAllParameters(['year', 'season']));
</script>

{#if user === undefined || $identity.id === -2}
  <LogInRestricted />
{:else}
  <div class="card">
    <p>
      <select bind:value={season}>
        <option value="WINTER">Winter</option>
        <option value="SPRING">Spring</option>
        <option value="SUMMER">Summer</option>
        <option value="FALL">Fall</option>
      </select>
      <input type="number" bind:value={year} />
    </p>

    {#await currentPrequels}
      <Skeleton card={false} count={5} height="0.9rem" list />
    {:then currentPrequels}
      <Prequels {currentPrequels} />
    {/await}

    <p></p>

    The count ratio is the number of episodes you've seen of any direct prequels, and the total
    number of episodes of all direct prequels.
  </div>
{/if}
