<?php
include("pdo.php");

function get_books($page = 1, $resultsPerPage = 10){
    global $pdo;

    $page = max(1, (int)$page);
    $offset = ($page - 1) * $resultsPerPage;

    $count_query = 'SELECT COUNT(*) FROM Livres AS L INNER JOIN Auteurs AS A ON L.auteur_id = A.auteur_id';
    $count = $pdo->query($count_query)->fetchColumn();
    $total_pages = ceil($count / $resultsPerPage);

    $statement = $pdo->prepare('SELECT L.livre_id, L.titre, L.annee_publication, A.nom, A.prenom
                                        FROM Livres AS L
                                        INNER JOIN Auteurs AS A ON L.auteur_id = A.auteur_id
                                        LIMIT :limit OFFSET :offset');
    $statement->bindValue(':limit', $resultsPerPage, PDO::PARAM_INT);
    $statement->bindValue(':offset', $offset, PDO::PARAM_INT);
    $statement->execute();
    return [
        'books' => $statement->fetchAll(PDO::FETCH_ASSOC),
        'current_page' => $page,
        'total_pages' => $total_pages,
        'total_results' => $count
    ];
}

function get_book($idBook = null) {
    global $pdo;

    if (is_numeric($idBook)) {
        $statement = $pdo->prepare('SELECT L.titre, L.annee_publication, L.resume, A.nom, A.prenom, A.auteur_id
                                        FROM Livres AS L
                                        INNER JOIN Auteurs AS A ON L.auteur_id = A.auteur_id
                                        WHERE L.livre_id = :id');

        $statement->bindValue(':id', $idBook, PDO::PARAM_INT);
        $statement->execute();
        return $statement->fetch(PDO::FETCH_ASSOC);
    }
}

function get_author($idAuthor = null) {
    global $pdo;

    if (is_numeric($idAuthor)) {
        $statement = $pdo->prepare('SELECT A.nom, A.prenom, L.titre, L.livre_id
                                        FROM Auteurs AS A
                                        INNER JOIN Livres AS L ON L.auteur_id = A.auteur_id
                                        WHERE A.auteur_id = :id');
        $statement->bindValue(':id', $idAuthor, PDO::PARAM_INT);
        $statement->execute();
        return $statement->fetchAll(PDO::FETCH_ASSOC);
    }

}