<?php

/**
 * FuzeWorks Framework Administration Plugin.
 *
 * The FuzeWorks PHP FrameWork
 *
 * Copyright (C) 2013-2020 i15
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * @author    i15
 * @copyright Copyright (c) 2013 - 2020, i15. (https://i15.nl)
 * @license   https://opensource.org/licenses/MIT MIT License
 *
 * @since Version 1.3.0
 *
 * @version Version 1.3.0
 */

namespace FuzeWorks\Administration;
use FuzeWorks\Administration\Attributes\DisplayAttribute;
use FuzeWorks\Administration\Attributes\HiddenAttribute;
use FuzeWorks\Administration\Attributes\IconAttribute;
use FuzeWorks\Administration\Attributes\PermissionAttribute;
use FuzeWorks\Administration\Attributes\PriorityAttribute;
use FuzeWorks\Administration\Events\AdminFindViewsEvent;
use FuzeWorks\Administration\Events\AdminGenerateSidebarEvent;
use FuzeWorks\Authentication\Model\Session;
use FuzeWorks\Events;
use FuzeWorks\Factory;
use FuzeWorks\Logger;
use FuzeWorks\Priority;
use FuzeWorks\Views;
use ReflectionClass;
use ReflectionException;
use ReflectionMethod;

class PageFinder
{


    protected Session $session;

    /**
     * Generates an array of all sidebar elements.
     *
     * First searches for all the available AdminViews. Then parses over all their methods and populates the array
     * using each method's attributes.
     *
     * @return array
     */
    public function generateSidebar(Session $session): array
    {
        $this->session = $session;

        Logger::log("Generating sidebar...");
        $event = Events::fireEvent('adminGenerateSidebarEvent');
        if ($event->isCancelled())
            return [];

        // First find all views
        $views = $this->findViews();
        Logger::log("Found " . count($views) . ' admin views.');

        // Then sort all those views into methods in the sidebar
        $sorted = $this->sortSidebar($views);

        // Log the result and return
        Logger::log("Found " . count($sorted) . ' entries for sidebar.');
        return $sorted;
    }

    /**
     * Find all views that have methods with attributes of a specific kind.
     *
     * @param string $attributeClass
     * @return string[]
     */
    public function findViewsWithAttribute(string $attributeClass): array
    {
        // First find all admin views
        $views = $this->findViews();
        return $this->sortByAttribute($views, $attributeClass);
    }

    /**
     * Parse over every view component path and find all admin views.
     *
     * Return a file list.
     *
     * @return string[]
     */
    protected function findViews(): array
    {
        /** @var Views $views */
        $views = Factory::getInstance('views');

        // First collect all the known paths
        $paths = [];
        for ($i = Priority::getHighestPriority(); $i<=Priority::getLowestPriority(); $i++)
            $paths[$i] = $views->getComponentPaths($i);

        // Then go over every individual paths
        $views = [];
        foreach ($paths as $priority => $foldersArray)
        {
            foreach ($foldersArray as $folder)
            {
                // Get the contents from the folder
                $contents = array_diff(scandir($folder), array('..', '.'));

                // Then go over the folders, and see which ones are an admin view
                foreach ($contents as $file)
                {
                    // If the file matches the expected filename, add it to the list
                    if (!str_starts_with($file, 'view.admin.'))
                        continue;

                    // Attempt to load the view
                    $viewFile = $folder . DS . $file;
                    $id = substr($file, 11, -4);
                    $className = 'Application\View\\' . ucfirst($id) . 'AdminView';
                    require_once($viewFile);
                    if (!class_exists($className))
                        continue;

                    $views[] = $className;
                }
            }
        }

        return $views;
    }

    /**
     * Returns all views which have methods which have Attributes with the attributeClassName
     *
     * @param string[] $views
     * @param string $attributeClassName
     * @return string[]
     */
    protected function sortByAttribute(array $views, string $attributeClassName): array
    {
        $out = [];
        foreach ($views as $view)
        {
            try {
                $reflector = new ReflectionClass($view);
            } catch (ReflectionException $e) {
                // If reflector doesn't work, simply ignore it.
                continue;
            }

            // Check if the class actually inherits AdminView
            if (!$reflector->isSubclassOf(AdminView::class))
                continue;

            // Select all methods
            $methods = $reflector->getMethods(ReflectionMethod::IS_PUBLIC);
            foreach ($methods as $method)
                if (!empty($method->getAttributes($attributeClassName)))
                    $out[] = $view;
        }

        return $out;
    }

    protected function sortSidebar(array $views): array
    {
        // Start sorting all methods
        $entries = [];
        foreach ($views as $view)
        {
            // Try and reflect on this class.
            try {
                $reflector = new ReflectionClass($view);
            } catch (ReflectionException $e) {
                // If that doesn't work, simply ignore it. Don't drag the whole interface down.
                continue;
            }

            // Check if this class actually inherits AdminView
            if (!$reflector->isSubclassOf("FuzeWorks\Administration\AdminView"))
                continue;

            // Determine view Id
            $id = strtolower(substr($reflector->getShortName(), 0, -9));

            // Select all methods
            $methods = $reflector->getMethods(ReflectionMethod::IS_PUBLIC);

            // And pass over all of them
            foreach ($methods as $method) {
                // Prepare the entry output
                $entry = [
                    'url' =>  ($id !== 'index' ? $id : '') . ($method->getName() !== 'index' ? '/' . $method->getName() : ''),
                    'priority' => Priority::NORMAL,
                    'display' => $reflector->getShortName() . '::' . $method->getName(),
                    'icon' => 'round'
                ];

                // Only allow the methods in the actual class. Not from the parent method.
                if ($method->class !== $view)
                    continue;

                // Read attributes
                // First read hidden attribute. If present, skip this method
                $hiddenAttributes = $method->getAttributes(HiddenAttribute::class);
                if (!empty($hiddenAttributes))
                    continue;

                // Then check for permissions
                $permissionAttributes = $method->getAttributes(PermissionAttribute::class);
                if (!empty($permissionAttributes))
                {
                    // Fetch nodes
                    $nodes = $permissionAttributes[0]->newInstance()->getValue();

                    // Check if any of the nodes are permitted
                    $found = false;
                    foreach ($nodes as $node)
                        if ($this->session->hasPermission($node))
                            $found = true;

                    // If not, skip
                    if (!$found)
                        continue;
                }

                // Then check for display attribute.
                $displayAttributes = $method->getAttributes(DisplayAttribute::class);
                if (!empty($displayAttributes))
                    $entry['display'] = $displayAttributes[0]->newInstance()->getValue();

                // Then check for icon
                $iconAttributes = $method->getAttributes(IconAttribute::class);
                if (!empty($iconAttributes))
                    $entry['icon'] = $iconAttributes[0]->newInstance()->getValue();

                // Then check for priority
                $priorityAttributes = $method->getAttributes(PriorityAttribute::class);
                if (!empty($priorityAttributes))
                    $entry['priority'] = $priorityAttributes[0]->newInstance()->getValue();

                // Add priority
                if (!isset($entries[$entry['priority']]))
                    $entries[$entry['priority']] = [];

                // Write to entries
                $entries[$entry['priority']][] = $entry;
            }
        }

        // Sort by priority
        $out = [];
        for ($i = Priority::getHighestPriority(); $i <= Priority::getLowestPriority(); $i++) {
            if (!isset($entries[$i]))
                continue;

            $p = $entries[$i];
            foreach ($p as $entry)
                $out[] = $entry;
        }

        // And finally return the sidebar entries
        return $out;
    }

}