/*!
  * Simple-Blog-Search
  * Copyright 2019, Baby Pepper
  * Licensed under the MIT License.
  */
'use strict';

var SimpleBlogSearch = function(args) {
  'use strict';
  $.ajax({
    url: args.searchDataPath,
    dataType: args.dataType,
    success: function( response ) {
      // get the contents from search data
      var $input = document.getElementById(args.searchInputID);
      if (!$input) return;
      var $resultContent = document.getElementById(args.resultsDivID);
      if ($("#" + args.searchInputID).length > 0) {
        $input.addEventListener('input', function () {
          var str = `<ul class="${args.resultULClass}">`;
          var keywordRegex = new RegExp(this.value.toLowerCase(), "g")
          $resultContent.innerHTML = "";
          if (this.value.trim().length <= 0) {
            return;
          }
          // perform local searching
          var count = 0
          args.processDataFunc(response).some(function (data) {
            var isMatch = false;
            if (!data.title || data.title.trim() === '') {
                data.title = "Untitled";
            }
            var data_title = data.title.trim().toLowerCase();
            var data_content = data.content.trim().replace(/(\r\n\t|\n|\r\t|\s)+/gm, " ")
            var data_content_lowercase = data_content.toLowerCase()
            var index_content = -1;
            var first_occur = -1;
            // only match articles with not empty contents
            if (data_content_lowercase !== '') {
                var matchTitles = data_title.match(keywordRegex)
                var matchContents = data_content_lowercase.match(keywordRegex)
                if (matchTitles != null) {
                  isMatch = true
                }
                if (matchContents != null) {
                  isMatch = true
                  index_content = data_content_lowercase.indexOf(matchContents[0]);
                }
                if (index_content < 0) {
                  index_content = 0
                }
                first_occur = index_content
            }

            // show search results
            if (isMatch) {
              str += `<li>
              <h2 class="post-list__post-title post-title"><a href="proxy.php?url=https%3A%2F%2Fanwarvic.github.io%2F%24%7Bdata.url%7D">${data.title}</a></h2>
              <div class="post-list__meta">
                <div class="post-list__meta--date date"> Published on: ${data.date} in ${data.collection}</div>
              </div>`;
              if (first_occur >= 0) {
                // cut out `args.captionSize` characters
                var start = first_occur - (args.captionSize/2);
                var end = first_occur + (args.captionSize/2);

                if (start < 0) {
                    start = 0;
                }

                if (start == 0) {
                    end = args.captionSize/2;
                }

                if (end > data_content.length) {
                    end = data_content.length;
                }
                
                // highlight search result
                var match_content = data_content.substring(start, end);
                if (matchContents != null) {
                    var regStr;
                    if (match_content.toLowerCase().includes(matchContents[0])) {
                      regStr = matchContents[0]
                    } else {
                      regStr = match_content.substring(20)
                    }
                    var reg = new RegExp(regStr.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'), "gi");
                    match_content = match_content.replace(reg,
                      `<em class="${args.highlightKeywordClass}">${regStr}</em>`);
                }

                str += `<p class="${args.resultParagraphClass}">${match_content}`
                if (end != data_content.length){
                  str += '...'
                }
                str += '</p>'
                str += `<hr class="post-list__divider">`
              }
              str += "</li>";
              count += 1;
            }
            return count == args.limit;
          });
          if (count === 0){
            str += args.noResultsMessage;
          }
          str += "</ul>";
          $resultContent.innerHTML = str;
        });
      }
    }
  });
}