"use client";

import { useEffect, useMemo, useState } from "react";

const ADMIN_TOKEN_KEY = "porthole_admin_token";

type Tag = {
  id: string;
  name: string;
  created_at: string;
};

type Album = {
  id: string;
  name: string;
  created_at: string;
};

export default function AdminPage() {
  const [token, setToken] = useState("");
  const [tokenInput, setTokenInput] = useState("");
  const [tokenMessage, setTokenMessage] = useState<string | null>(null);

  const [tags, setTags] = useState<Tag[]>([]);
  const [tagsError, setTagsError] = useState<string | null>(null);
  const [tagsLoading, setTagsLoading] = useState(false);
  const [newTag, setNewTag] = useState("");

  const [albums, setAlbums] = useState<Album[]>([]);
  const [albumsError, setAlbumsError] = useState<string | null>(null);
  const [albumsLoading, setAlbumsLoading] = useState(false);
  const [newAlbum, setNewAlbum] = useState("");

  useEffect(() => {
    if (typeof window === "undefined") return;
    const stored = sessionStorage.getItem(ADMIN_TOKEN_KEY) ?? "";
    setToken(stored);
    setTokenInput(stored);
  }, []);

  const adminHeaders = useMemo(() => {
    if (!token) return null;
    return { "X-Porthole-Admin-Token": token };
  }, [token]);

  async function loadTags() {
    if (!adminHeaders) {
      setTagsError("Set admin token first.");
      return;
    }

    setTagsLoading(true);
    setTagsError(null);
    try {
      const res = await fetch("/api/tags", {
        headers: adminHeaders,
        cache: "no-store",
      });
      if (!res.ok) throw new Error(`tags_fetch_failed:${res.status}`);
      const json = (await res.json()) as Tag[];
      setTags(json);
    } catch (err) {
      setTagsError(err instanceof Error ? err.message : String(err));
    } finally {
      setTagsLoading(false);
    }
  }

  async function loadAlbums() {
    if (!adminHeaders) {
      setAlbumsError("Set admin token first.");
      return;
    }

    setAlbumsLoading(true);
    setAlbumsError(null);
    try {
      const res = await fetch("/api/albums", {
        headers: adminHeaders,
        cache: "no-store",
      });
      if (!res.ok) throw new Error(`albums_fetch_failed:${res.status}`);
      const json = (await res.json()) as Album[];
      setAlbums(json);
    } catch (err) {
      setAlbumsError(err instanceof Error ? err.message : String(err));
    } finally {
      setAlbumsLoading(false);
    }
  }

  async function handleSaveToken(event: React.FormEvent) {
    event.preventDefault();
    if (typeof window === "undefined") return;
    const trimmed = tokenInput.trim();
    if (trimmed) {
      sessionStorage.setItem(ADMIN_TOKEN_KEY, trimmed);
      setToken(trimmed);
      setTokenMessage("Token saved for this session.");
    } else {
      sessionStorage.removeItem(ADMIN_TOKEN_KEY);
      setToken("");
      setTokenMessage("Token cleared.");
    }
  }

  async function handleCreateTag(event: React.FormEvent) {
    event.preventDefault();
    if (!adminHeaders) {
      setTagsError("Set admin token first.");
      return;
    }
    if (!newTag.trim()) {
      setTagsError("Tag name is required.");
      return;
    }
    try {
      setTagsError(null);
      const res = await fetch("/api/tags", {
        method: "POST",
        headers: { ...adminHeaders, "Content-Type": "application/json" },
        body: JSON.stringify({ name: newTag.trim() }),
      });
      if (!res.ok) throw new Error(`tag_create_failed:${res.status}`);
      setNewTag("");
      await loadTags();
    } catch (err) {
      setTagsError(err instanceof Error ? err.message : String(err));
    }
  }

  async function handleCreateAlbum(event: React.FormEvent) {
    event.preventDefault();
    if (!adminHeaders) {
      setAlbumsError("Set admin token first.");
      return;
    }
    if (!newAlbum.trim()) {
      setAlbumsError("Album name is required.");
      return;
    }
    try {
      setAlbumsError(null);
      const res = await fetch("/api/albums", {
        method: "POST",
        headers: { ...adminHeaders, "Content-Type": "application/json" },
        body: JSON.stringify({ name: newAlbum.trim() }),
      });
      if (!res.ok) throw new Error(`album_create_failed:${res.status}`);
      setNewAlbum("");
      await loadAlbums();
    } catch (err) {
      setAlbumsError(err instanceof Error ? err.message : String(err));
    }
  }

  return (
    <main style={{ padding: 16, display: "grid", gap: 20, maxWidth: 720 }}>
      <header>
        <h1 style={{ marginTop: 0 }}>Admin</h1>
        <p style={{ color: "#555" }}>
          Manage tags and albums. Admin token is stored in sessionStorage.
        </p>
      </header>

      <section style={{ border: "1px solid #ddd", borderRadius: 12, padding: 16 }}>
        <h2 style={{ marginTop: 0 }}>Admin Token</h2>
        <form onSubmit={handleSaveToken} style={{ display: "grid", gap: 8 }}>
          <input
            type="password"
            placeholder="X-Porthole-Admin-Token"
            value={tokenInput}
            onChange={(e) => setTokenInput(e.target.value)}
            style={{ padding: 8, borderRadius: 6, border: "1px solid #ccc" }}
          />
          <div style={{ display: "flex", gap: 8 }}>
            <button type="submit">Save token</button>
            <button
              type="button"
              onClick={() => {
                setTokenInput("");
                setToken("");
                if (typeof window !== "undefined") {
                  sessionStorage.removeItem(ADMIN_TOKEN_KEY);
                }
                setTokenMessage("Token cleared.");
              }}
            >
              Clear
            </button>
          </div>
          {tokenMessage ? (
            <div style={{ fontSize: 12, color: "#444" }}>{tokenMessage}</div>
          ) : null}
        </form>
      </section>

      <section style={{ border: "1px solid #ddd", borderRadius: 12, padding: 16 }}>
        <h2 style={{ marginTop: 0 }}>Tags</h2>
        <form onSubmit={handleCreateTag} style={{ display: "flex", gap: 8 }}>
          <input
            type="text"
            placeholder="New tag name"
            value={newTag}
            onChange={(e) => setNewTag(e.target.value)}
            style={{ flex: 1, padding: 8, borderRadius: 6, border: "1px solid #ccc" }}
          />
          <button type="submit">Create</button>
          <button type="button" onClick={loadTags} disabled={tagsLoading}>
            {tagsLoading ? "Loading..." : "Refresh"}
          </button>
        </form>
        {tagsError ? (
          <div style={{ color: "#b00", marginTop: 8 }}>{tagsError}</div>
        ) : null}
        <ul style={{ marginTop: 12, paddingLeft: 16 }}>
          {tags.length === 0 ? (
            <li style={{ color: "#666" }}>No tags yet.</li>
          ) : (
            tags.map((tag) => <li key={tag.id}>{tag.name}</li>)
          )}
        </ul>
      </section>

      <section style={{ border: "1px solid #ddd", borderRadius: 12, padding: 16 }}>
        <h2 style={{ marginTop: 0 }}>Albums</h2>
        <form onSubmit={handleCreateAlbum} style={{ display: "flex", gap: 8 }}>
          <input
            type="text"
            placeholder="New album name"
            value={newAlbum}
            onChange={(e) => setNewAlbum(e.target.value)}
            style={{ flex: 1, padding: 8, borderRadius: 6, border: "1px solid #ccc" }}
          />
          <button type="submit">Create</button>
          <button type="button" onClick={loadAlbums} disabled={albumsLoading}>
            {albumsLoading ? "Loading..." : "Refresh"}
          </button>
        </form>
        {albumsError ? (
          <div style={{ color: "#b00", marginTop: 8 }}>{albumsError}</div>
        ) : null}
        <ul style={{ marginTop: 12, paddingLeft: 16 }}>
          {albums.length === 0 ? (
            <li style={{ color: "#666" }}>No albums yet.</li>
          ) : (
            albums.map((album) => <li key={album.id}>{album.name}</li>)
          )}
        </ul>
      </section>
    </main>
  );
}