<?php

require __DIR__ . "/../vendor/autoload.php";

use App\Classes\ApiHandler;
use GuzzleHttp\Client;

class BookImportHandler extends ApiHandler
{
  private string $bookImportToken;

  public function __construct()
  {
    parent::__construct();
    $this->ensureCliAccess();
    $this->bookImportToken = $_ENV["BOOK_IMPORT_TOKEN"] ?? getenv("BOOK_IMPORT_TOKEN");
  }

  public function handleRequest(): void
  {
    $input = json_decode(file_get_contents("php://input"), true);

    if (!$input) {
      $this->sendErrorResponse("Invalid or missing JSON body", 400);
    }

    $providedToken = $input["token"] ?? null;
    $isbn = $input["isbn"] ?? null;

    if ($providedToken !== $this->bookImportToken) {
      $this->sendErrorResponse("Unauthorized access", 401);
    }

    if (!$isbn) {
      $this->sendErrorResponse("isbn parameter is required", 400);
    }

    try {
      $bookData = $this->fetchBookData($isbn);
      $this->processBook($bookData);
      $this->sendResponse(["message" => "Book imported successfully"], 200);
    } catch (\Exception $e) {
      $this->sendErrorResponse("Error: " . $e->getMessage(), 500);
    }
  }

  private function fetchBookData(string $isbn): array
  {
    $client = new Client();
    $response = $client->get("https://openlibrary.org/api/books", [
      "query" => [
        "bibkeys" => "ISBN:{$isbn}",
        "format" => "json",
        "jscmd" => "data",
      ],
      "headers" => ["Accept" => "application/json"],
    ]);

    $data = json_decode($response->getBody(), true);
    $bookKey = "ISBN:{$isbn}";

    if (empty($data[$bookKey])) {
      throw new \Exception("Book data not found for ISBN: {$isbn}");
    }

    return $data[$bookKey];
  }

  private function processBook(array $bookData): void
  {
    $isbn =
      $bookData["identifiers"]["isbn_13"][0] ??
      ($bookData["identifiers"]["isbn_10"][0] ?? null);
    $title = $bookData["title"] ?? null;
    $author = $bookData["authors"][0]["name"] ?? null;
    $description = $bookData["description"] ?? ($bookData["notes"] ?? "");

    if (!$isbn || !$title || !$author) {
      throw new \Exception("Missing essential book data (title, author, or ISBN).");
    }

    $existingBook = $this->getBookByISBN($isbn);
    if ($existingBook) {
      throw new \Exception("Book with ISBN {$isbn} already exists.");
    }

    $bookPayload = [
      "isbn" => $isbn,
      "title" => $title,
      "author" => $author,
      "description" => $description,
      "read_status" => "want to read",
      "slug" => "/reading/books/" . $isbn,
    ];

    $this->makeRequest("POST", "books", ["json" => $bookPayload]);
  }

  private function getBookByISBN(string $isbn): ?array
  {
    $response = $this->fetchFromApi("books", "isbn=eq." . urlencode($isbn));
    return $response[0] ?? null;
  }
}

$handler = new BookImportHandler();
$handler->handleRequest();