<?php

/**
 * SysCMS - Content Management System
 *
 * Copyright (c) 2025 Marco Costa
 * All rights reserved.
 *
 * Author: Marco Costa
 * Email: contato@syspanel.com.br
 * Project: SysCMS
 *
 * This software is licensed, not sold.
 * Permission is granted to use this software
 * subject to the terms of the SysCMS Commercial License.
 *
 * Redistribution, sublicensing, resale, or
 * disclosure of this software, in whole or in part,
 * is strictly prohibited without prior written permission.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND.
 */

namespace Modules\PageBuilder\Classes;

/**
 * Simple pagination class for PageBuilder module
 */
class Paginator
{
    /**
     * Current page
     *
     * @var int
     */
    protected $currentPage;

    /**
     * Items per page
     *
     * @var int
     */
    protected $perPage;

    /**
     * Total items
     *
     * @var int
     */
    protected $total;

    /**
     * Path for pagination links
     *
     * @var string
     */
    protected $path;

    /**
     * Query parameters
     *
     * @var array
     */
    protected $query;

    /**
     * Constructor
     *
     * @param int $total
     * @param int $perPage
     * @param int $currentPage
     * @param string $path
     * @param array $query
     */
    public function __construct(int $total, int $perPage, int $currentPage = 1, string $path = '', array $query = [])
    {
        $this->total = $total;
        $this->perPage = $perPage;
        $this->currentPage = max(1, $currentPage);
        $this->path = $path ?: $_SERVER['REQUEST_URI'] ?? '';
        $this->query = $query;
    }

    /**
     * Get current page
     *
     * @return int
     */
    public function getCurrentPage(): int
    {
        return $this->currentPage;
    }

    /**
     * Get items per page
     *
     * @return int
     */
    public function getPerPage(): int
    {
        return $this->perPage;
    }

    /**
     * Get total items
     *
     * @return int
     */
    public function getTotal(): int
    {
        return $this->total;
    }

    /**
     * Get last page
     *
     * @return int
     */
    public function getLastPage(): int
    {
        return max(1, (int) ceil($this->total / $this->perPage));
    }

    /**
     * Get offset for database query
     *
     * @return int
     */
    public function getOffset(): int
    {
        return ($this->currentPage - 1) * $this->perPage;
    }

    /**
     * Check if there are more items
     *
     * @return bool
     */
    public function hasMorePages(): bool
    {
        return $this->currentPage < $this->getLastPage();
    }

    /**
     * Check if there are previous pages
     *
     * @return bool
     */
    public function hasPreviousPages(): bool
    {
        return $this->currentPage > 1;
    }

    /**
     * Get URL for a specific page
     *
     * @param int $page
     * @return string
     */
    public function getUrl(int $page): string
    {
        $query = $this->query;
        $query['page'] = $page;

        $queryString = http_build_query($query);

        // Remove the existing query string from the path
        $path = strtok($this->path, '?');

        return $path . ($queryString ? '?' . $queryString : '');
    }

    /**
     * Get previous page URL
     *
     * @return string|null
     */
    public function getPreviousPageUrl(): ?string
    {
        if (!$this->hasPreviousPages()) {
            return null;
        }

        return $this->getUrl($this->currentPage - 1);
    }

    /**
     * Get next page URL
     *
     * @return string|null
     */
    public function getNextPageUrl(): ?string
    {
        if (!$this->hasMorePages()) {
            return null;
        }

        return $this->getUrl($this->currentPage + 1);
    }

    /**
     * Get array of page numbers to display
     *
     * @param int $onEachSide
     * @return array
     */
    public function getPageNumbers(int $onEachSide = 3): array
    {
        $lastPage = $this->getLastPage();
        $currentPage = $this->currentPage;

        if ($lastPage <= ($onEachSide * 2) + 1) {
            return range(1, $lastPage);
        }

        $pages = [];

        // First page
        $pages[] = 1;

        // Pages before current
        $start = max(2, $currentPage - $onEachSide);
        $end = min($lastPage - 1, $currentPage + $onEachSide);

        if ($start > 2) {
            $pages[] = '...';
        }

        for ($i = $start; $i <= $end; $i++) {
            $pages[] = $i;
        }

        if ($end < $lastPage - 1) {
            $pages[] = '...';
        }

        // Last page
        if ($lastPage > 1) {
            $pages[] = $lastPage;
        }

        return $pages;
    }

    /**
     * Convert paginator to array for template rendering
     *
     * @return array
     */
    public function toArray(): array
    {
        return [
            'current_page' => $this->getCurrentPage(),
            'per_page' => $this->getPerPage(),
            'total' => $this->getTotal(),
            'last_page' => $this->getLastPage(),
            'offset' => $this->getOffset(),
            'has_more_pages' => $this->hasMorePages(),
            'has_previous_pages' => $this->hasPreviousPages(),
            'previous_page_url' => $this->getPreviousPageUrl(),
            'next_page_url' => $this->getNextPageUrl(),
            'page_numbers' => $this->getPageNumbers(),
        ];
    }
}