fetch_nptel.php

<?php

session_start();
require_once '../vendor/autoload.php';
use Elasticsearch\ClientBuilder;
$client = ClientBuilder::create()->setHosts(['127.0.0.1:9200'])->build();

$output = '';
$page_array[]=1;
$limit = '5';
$page = 1;
if($_POST['page'] > 1)
{
  $start = (($_POST['page'] - 1) * $limit);
  $page = $_POST['page'];
}
else
{
  $start = 0;
}
if($_POST['query'] != ''){
  $search = $_POST["query"];
  $params=[
    'body'=>[
      'query' => [
        'bool'=> [
          'should'=> [
            [
              'multi_match'=> [
                'query'=> $search,
                'fields'=> ['title','Cateagory','Cateagory.english','University.english','Level :','Course Type :'],
                'type'=> 'most_fields',
                'boost'=> 3,
                'minimum_should_match'=> '75%',
                'cutoff_frequency'=> 0.10
              ]
            ],
            [
              'multi_match'=> [
                'query'=> $search,
                'fields'=> ['Duration','Level :','Professor']
                , 'type'=> 'most_fields',
                'minimum_should_match'=> '75%', 
                'cutoff_frequency'=> 0.10
              ]
            ]
          ]
        ]  
      ],
      'from'=>0,
      'size'=>350
    ]
  ];

  $params2=[
    'body'=>[
      'query' => [
        'bool'=> [
          'should'=> [
            [
              'multi_match'=> [
                'query'=> $search,
                'fields'=> ['title','Cateagory','Cateagory.english','University.english','Level :','Course Type :'],
                'type'=> 'most_fields',
                'boost'=> 3,
                'minimum_should_match'=> '75%',
                'cutoff_frequency'=> 0.10
              ]
            ],
            [
              'multi_match'=> [
                'query'=> $search,
                'fields'=> ['Duration','Level :','Professor']
                , 'type'=> 'most_fields',
                'minimum_should_match'=> '75%', 
                'cutoff_frequency'=> 0.10
              ]
            ]
          ]
        ]  
      ],
      'from'=>$start,
      'size'=>$limit
    ]
  ];

  $query = $client->search($params);
  $total_data = count($query['hits']['hits']); 


  $query = $client->search($params2);
  if($query['hits']['total']>=1){
    $result = $query['hits']['hits'];
  }

  $output .= '
  <div style="font-size: 18px; margin-bottom: 15px; margin-top: -10px;">Search results for "<b>'.$search.'</b>"</div>
  <div style="margin-bottom: 5px; margin-top: -10px;">Found '.$total_data.' results</div>
  ';
  if($total_data > 0)
  {
    foreach($result as $row)
    {
     if(isset($row["_source"]["link"])){
      $link = $row["_source"]["link"];
      $output .='
      <div class="card card-1">
      <div id="sticky_header" class="title_header">
      <div class="title"><a class="title_link" href="' . $link . '">'.$row["_source"]["title"].'</a></div>
      <div class="link"><a href="' . $link . '">'.$row["_source"]["link"].'</a></div>
      <hr style="margin-top: 10px;">
      </div>
      <div class="description" style="padding-bottom: 10px;">
      <div style="padding-bottom: 5px;"><b>Description:</b></div>
      <div>'.$row["_source"]["description"].'</div>
      </div>
      <hr style="margin-top: -5px;">
      <div class="div_university">
      <div class="professor" style="font-size: 15px; margin-top: -10px;  margin-bottom: 5px;"><b>Guided '.$row["_source"]["Professor"].'</b></div>
      <div class="university" style="font-size: 15px; margin-top: -5px; margin-bottom: 10px;"><b>Offered By: </b><em style="font-size: 15px;">'.$row["_source"]["University"].'</em></div>
      </div>
      </div>
      ';
    }
  }
}

$output .= '
<br>
<div align="center">
<ul class="pagination">
';

$total_links = ceil($total_data/$limit);
$previous_link = '';
$next_link = '';
$page_link = '';

//echo $total_links;

if($total_links > 4)
{
  if($page < 5)
  {
    for($count = 1; $count <= 5; $count++)
    {
      $page_array[] = $count;
    }
    $page_array[] = '...';
    $page_array[] = $total_links;
  }
  else
  {
    $end_limit = $total_links - 5;
    if($page > $end_limit)
    {
      $page_array[] = 1;
      $page_array[] = '...';
      for($count = $end_limit; $count <= $total_links; $count++)
      {
        $page_array[] = $count;
      }
    }
    else
    {
      $page_array[] = 1;
      $page_array[] = '...';
      for($count = $page - 1; $count <= $page + 1; $count++)
      {
        $page_array[] = $count;
      }
      $page_array[] = '...';
      $page_array[] = $total_links;
    }
  }
}
else
{
  for($count = 1; $count <= $total_links; $count++)
  {
    $page_array[] = $count;
  }
}
for($count = 1; $count < count($page_array); $count++)
{
  if($page == $page_array[$count])
  {
    $page_link .= '
    <li class="page-item active">
    <a class="page-link" href="#">'.$page_array[$count].' <span class="sr-only">(current)</span></a>
    </li>
    ';

    $previous_id = $page_array[$count] - 1;
    if($previous_id > 0)
    {
      $previous_link = '<li class="page-item"><a class="page-link" href="javascript:void(0)" data-page_number="'.$previous_id.'">Previous</a></li>';
    }
    else
    {
      $previous_link = '
      <li class="page-item disabled">
      <a class="page-link" href="#">Previous</a>
      </li>
      ';
    }
    $next_id = $page_array[$count] + 1;
    if($next_id >= $total_links)
    {
      $next_link = '
      <li class="page-item disabled">
      <a class="page-link" href="#">Next</a>
      </li>
      ';
    }
    else
    {
      $next_link = '<li class="page-item"><a class="page-link" href="javascript:void(0)" data-page_number="'.$next_id.'">Next</a></li>';
    }
  }
  else
  {
    if($page_array[$count] == '...')
    {
      $page_link .= '
      <li class="page-item disabled">
      <a class="page-link" href="#">...</a>
      </li>
      ';
    }
    else
    {
      $page_link .= '
      <li class="page-item"><a class="page-link" href="javascript:void(0)" data-page_number="'.$page_array[$count].'">'.$page_array[$count].'</a></li>
      ';
    }
  }
}

$output .= $previous_link . $page_link . $next_link;
$output .= '
</ul>

</div>
</div>
';
echo $output;
}
?>