<?php

function solr_search($search){

  // Assemble a query string to send to Solr. This uses the Solr hostname from config.env. Solr's query syntax can be found at many sites including https://lucene.apache.org/solr/guide/6_6/the-standard-query-parser.html
  // This query retrieves only the bib identifier field for records which satisfy the search query
  $solrurl = 'http://' . $_ENV["SOLR_HOSTNAME"] . ':' . $_ENV["SOLR_PORT"] . '/solr/' . $_ENV["SOLR_CORE"] . '/select?q.op=OR&q=content%3A' . $search . '&wt=json';

  // Perform Curl request on the Solr API
  $ch = curl_init();
  curl_setopt($ch, CURLOPT_URL, $solrurl);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
  curl_setopt($ch, CURLOPT_HEADER, FALSE);
  curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'GET');
  $response = curl_exec($ch);
  curl_close($ch);

  // Turn the API response into useful Json
  $json = json_decode($response);

  // If no results are found, display a message
  if ($json->response->numFound == '0'){
    $output = 'No results found';
  }
  else{
    foreach ($json->response->docs as $result){
      $content = $result->content;
      $result_output = parse_result($content);
      $results[] = $result_output;
    }
  }
  return $results;
}

function parse_result($input){

  //Set document reference number (used for OPS API)
  preg_match('/=D\s(([^\s]*)\s([^\s]*)\s([^\s]*))/', $input, $doc_ref);
  $output['doc_ref'] = str_replace(' ','',$doc_ref[1]);

  // Search for the application ID in the content element and display it
  preg_match('/Application.*\n(.*)\n/', $input, $application_id);
  $output['application_id'] = $application_id[1];

  // Search for the EPO publication URL in the content element and display it
  preg_match('/Publication.*\n(.*)\n/', $input, $epo_publication);
  $output['epo_publication_url'] = $epo_publication[1];

  // Search for the IPC publication URL in the content element and display it
  preg_match('/IPC.*\n(.*)\n/', $input, $ipc_publication);
  $output['ipc_publication_url'] = $ipc_publication[1];

  // Search for the title in the content element and display it
  preg_match('/Title.*\n(.*)\n/', $input, $title);
  $output['title'] = $title[1];

  // Search for the abstract in the content element and display it
  if (preg_match('/Abstract.*\n(.*)\n/', $input, $abstract)){
    $output['abstract'] = $abstract[1];
  }
  else {
    preg_match('/\(.\) \\n\\n(.*)\\n/', $input, $abstract);
    $output['abstract'] = $abstract[1];
  }

  return $output;

}

function get_random_record(){

    // Generate a random number for sorting by random
    $random = rand();

    // Assemble a query string to send to Solr. This uses the Solr hostname from config.env. Solr's query syntax can be found at many sites including https://lucene.apache.org/solr/guide/6_6/the-standard-query-parser.html
    // This query retrieves only the bib identifier field for records which satisfy the search query
    $solrurl = 'http://' . $_ENV["SOLR_HOSTNAME"] . ':' . $_ENV["SOLR_PORT"] . '/solr/' . $_ENV["SOLR_CORE"] . '/select?q.op=OR&q=*%3A*&wt=json&sort=random_' . $random . '%20asc';

    // Perform Curl request on the Solr API
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $solrurl);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
    curl_setopt($ch, CURLOPT_HEADER, FALSE);
    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'GET');
    $response = curl_exec($ch);
    curl_close($ch);

    // Turn the API response into useful Json
    $json = json_decode($response);

    // Pick a random key out of the docs array
    $random = array_rand($json->response->docs);

    //Set content variable
    $content = $json->response->docs[$random]->content;

    return $content;
}

function one_random_record (){

  $content = get_random_record();

  $output = parse_result($content);

  return $output;

}

function ten_random_titles (){

  for ($x=0; $x <= 9; $x++) {
    $random = get_random_record();
    // Search for the title in the content element and display it
    preg_match('/Title.*\n(.*)\n/', $random, $title);
    $output[$x] = $title[1];
  }

  return $output;

}


?>