<?php
namespace Drupal\related_ror\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\JsonResponse;
use Drupal\Core\Cache\CacheableJsonResponse;
use Drupal\Core\Cache\CacheableMetadata;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Drupal\Core\Template\TwigEnvironment;
use Drupal\node\NodeInterface;

class RelatedRorController extends ControllerBase {
    protected $state;
    protected $twig;
    public function __construct($state, TwigEnvironment $twig) {
        $this->state = $state;
        $this->twig = $twig;
    }

    public static function create(ContainerInterface $container) {
        return new static(
            $container->get('state'),
            $container->get('twig')
        );
    }
    private function nodeToLinkdata($node_entity) {
        $arr = $node_entity->toArray();
        if(count($arr['body']) > 0) { // c'e' gente che pubblica articoli senza body
            $body = $arr['body'][0]['value'];
        } else {
            $body = '';
        }
        return array(
            'nid'   => intval($arr['nid'] [0] ['value']),
            'title' => $arr['title'][0]['value'],
            //'body'  => $arr['body'][0] ['value'],
            'summary' => htmlspecialchars(substr(
                html_entity_decode(strip_tags($body)), 0, 3500), ENT_XML1, 'UTF-8'),
            'url'   => $arr['path'][0] ['alias']
        );
    }

    private function queryNearInTime(int $time, int $days = 7, int $limit = 0): array {
        $arg = array('ror_news', 'redazionali', 'news_trasmissioni');
        $query = \Drupal::entityQuery('node');
        $query = \Drupal::database()->select('node', 'n');
        $query->addJoin('INNER', 'node__field_tx_date', 'dt', 'n.nid=dt.entity_id');
        $query->addJoin('INNER', 'node_field_data', 'field', 'n.nid=field.nid');
        $query ->addField('n', 'nid');
        $query->addExpression("CAST(UNIX_TIMESTAMP(field_tx_date_value) as UNSIGNED)", 'ts');
        $query->addExpression("ABS(cast(UNIX_TIMESTAMP(field_tx_date_value) as signed) - $time)", 'dist');
        $query->condition('field.status', '1');
        $query->condition('n.type', $arg, 'IN');
        $query->where('CAST(UNIX_TIMESTAMP(dt.field_tx_date_value) as UNSIGNED) > :from', array('from' => $time - 3600*24*$days));
        $query->where('CAST(UNIX_TIMESTAMP(dt.field_tx_date_value) as UNSIGNED) < :to', array('to' => $time + 3600*24*$days));
        $query->orderBy('dist', 'ASC');
        if($limit > 0) {
            $query->range(0, $limit);
        }
        if($query->preExecute() !== TRUE) {
            return null;
        }
        $nids = $query->execute()->fetchCol(0);
        return $nids;
    }

    private function presentNids(array $nids) {
        $nodes_e = \Drupal\node\Entity\Node::loadMultiple($nids);
        $data = ['nodes' => []];
        foreach($nodes_e as $nid => $node) {
            $nodedata = $this->nodeToLinkdata($node);
            array_push($data['nodes'], $nodedata);
        }

        return $data;
    }

    public function relatedTime() {
        $nid = \Drupal::request()->query->get('nid');
        if($nid == null) {
            return new Response("Must supply a NID", 400, array('Content-Type' => 'text/plain'));
        }
        if(!is_numeric($nid)) {
            return new Response("NID must be integer, not `$nid`", 400, array('Content-Type' => 'text/plain'));
        }
        $nid = intval($nid);
        $node = \Drupal\node\Entity\Node::load($nid);
        if($node == null) {
            return new Response("Node not found", 404, array('Content-Type' => 'text/plain'));
        }
        if($this->isFilteredOut($node)) {
            return new Response("Node has no similarity", 404, array('Content-Type' => 'text/plain'));
        }
        $time = intval($node->getCreatedTime());
        $nearnodes = $this->presentNids(array_filter(
            $this->queryNearInTime($time, $days=4, $limit=20),
            function ($n) use ($nid): bool { return intval($n) != $nid; }));
        $resp = $this->cachedJsonResp(array('time' => $nearnodes));
        return $resp;
    }

    public function relatedTrx() {
        // TODO: get node time
        // TODO: queryNearInTime($time)
        $nid = \Drupal::request()->query->get('nid');
        if($nid == null) {
            return new Response("Must supply a NID", 400, array('Content-Type' => 'text/plain'));
        }
        $content = "asd $nid";
        $resp = new Response($content, 500, array( 'Content-Type' => 'text/plain'));
        return $resp;
    }

    private function getTermWeight(int $termid): int {
        $term = \Drupal\taxonomy\Entity\Term::load($termid);
        $query = \Drupal::database()->select('taxonomy_index', 'ti');
        $query->fields('ti', ['nid']);
        $query->condition('ti.tid', $termid);
        $cnt = $query->countQuery()->execute()->fetchField();
        if($cnt < 100) {
            return 2;
        }
        return 1;
    }

    private function getSimilarity(array $orig, array $other): int {
        if(!array_key_exists('field_tags', $orig) || count($orig['field_tags']) == 0 || 
            !array_key_exists('field_tags', $other) || count($other['field_tags']) == 0) {
            return 0;
        }
        $orig_tags = array_map(function($t) { return $t['target_id']; }, $orig['field_tags']);
        $other_tags = array_map(function($t) { return $t['target_id']; }, $other['field_tags']);
        $both = array_intersect($orig_tags, $other_tags);
        $weighted = array_map([$this, 'getTermWeight'], $both);
        return array_sum($weighted) || 0;
    }

    private function cachedJsonResp(array $data): Response {
        $resp = new JsonResponse($data, 200, ['cache-control' => 'public, max-age=900']);
        return $resp;
    }

    private function isFilteredOut(\Drupal\node\Entity\Node $node) {
        if($node->getType() === 'page')
            return true;

        return false;
    }

    public function relatedTopic() {
        // TODO: get node time
        // TODO: queryNearInTime($time)
        $nid = \Drupal::request()->query->get('nid');
        if($nid == null) {
            return new Response("Must supply a NID", 400, array('Content-Type' => 'text/plain'));
        }
        if(!is_numeric($nid)) {
            return new Response("NID must be integer, not `$nid`", 400, array('Content-Type' => 'text/plain'));
        }
        $nid = intval($nid);
        $node = \Drupal\node\Entity\Node::load($nid);
        if($node == null) {
            return new Response("Node not found", 404, array('Content-Type' => 'text/plain'));
        }
        if($this->isFilteredOut($node)) {
            return new Response("Node similarity disallowed", 403, array('Content-Type' => 'text/plain'));
        }
        $orig_arr = $node->toArray();
        $time = intval($node->getCreatedTime());

        $goodnids = [];
        $scores = [];
        $other_e = \Drupal\node\Entity\Node::loadMultiple($this->queryNearInTime($time, $days=30, $limit=100));
        foreach($other_e as $other_nid => $other_node) {
            if(intval($other_nid) === $nid) {
                continue;
            }
            $score = $this->getSimilarity($orig_arr, $other_node->toArray());
            if($score > 0) {
                $scores[$other_nid] =  $score;
            }
        }
        arsort($scores);
        foreach($scores as $nid => $score) {
            array_push($goodnids, $nid);
        }
        $resp = $this->cachedJsonResp(['topic' => $this->presentNids($goodnids)]);
        return $resp;
    }
}