// A local search script with the help of [hexo-generator-search](https://github.com/PaicHyperionDev/hexo-generator-search)
// Copyright (C) 2017 
// Liam Huang <http://github.com/Liam0205>

var searchFunc = function (path, search_id, content_id) {
    // 0x00. environment initialization
    'use strict';
    var BTN = "<i id='local-search-close'>×</i>";
    var $input = document.getElementById(search_id);
    var $resultContent = document.getElementById(content_id);
    $resultContent.innerHTML = BTN + "<ul><span class='local-search-empty'>首次搜索，正在载入索引文件，请稍后……<span></ul>";
    $.ajax({
      // 0x01. load xml file
      url: path,
      dataType: "xml",
      success: function (xmlResponse) {
        // 0x02. parse xml file
        var datas = $("entry", xmlResponse).map(function () {
          return {
            title: $("title", this).text(),
            content: $("content", this).text(),
            url: $("url", this).text()
          };
        }).get();
        $resultContent.innerHTML = "";
  
        $input.addEventListener('input', function () {
          // 0x03. parse query to keywords list
          var str = '<ul class=\"search-result-list\">';
          var keywords = this.value.trim().toLowerCase().split(/[\s\-]+/);
          $resultContent.innerHTML = "";
          if (this.value.trim().length <= 0) {
            return;
          }
          // 0x04. perform local searching
          datas.forEach(function (data) {
            var isMatch = true;
            var content_index = [];
            if (!data.title || data.title.trim() === '') {
              data.title = "Untitled";
            }
            var orig_data_title = data.title.trim();
            var data_title = orig_data_title.toLowerCase();
            var orig_data_content = data.content.trim().replace(/<[^>]+>/g, "");
            var data_content = orig_data_content.toLowerCase();
            var data_url = data.url;
            var index_title = -1;
            var index_content = -1;
            var first_occur = -1;
            // only match artiles with not empty contents
            if (data_content !== '') {
              keywords.forEach(function (keyword, i) {
                index_title = data_title.indexOf(keyword);
                index_content = data_content.indexOf(keyword);
  
                if (index_title < 0 && index_content < 0) {
                  isMatch = false;
                } else {
                  if (index_content < 0) {
                    index_content = 0;
                  }
                  if (i == 0) {
                    first_occur = index_content;
                  }
                  // content_index.push({index_content:index_content, keyword_len:keyword_len});
                }
              });
            } else {
              isMatch = false;
            }
            // 0x05. show search results
            if (isMatch) {
              str += "<li><a href='" + data_url + "' class='search-result-title' target='_blank'>" + orig_data_title + "</a>";
              var content = orig_data_content;
              if (first_occur >= 0) {
                // cut out 100 characters
                var start = first_occur - 20;
                var end = first_occur + 30;
  
                if (start < 0) {
                  start = 0;
                }
  
                if (start == 0) {
                  end = 100;
                }
  
                if (end > content.length) {
                  end = content.length;
                }
  
                var match_content = content.substr(start, end);
  
                // highlight all keywords
                keywords.forEach(function (keyword) {
                  var regS = new RegExp(keyword, "gi");
                  match_content = match_content.replace(regS, "<em class=\"search-keyword\">" + keyword + "</em>");
                });
  
                str += "<p class=\"search-result\">" + match_content + "...</p>"
              }
              str += "</li>";
            }
          });
          str += "</ul>";
          if (str.indexOf('<li>') === -1) {
            return $resultContent.innerHTML = BTN + "<ul><span class='local-search-empty'>没有找到内容，请尝试更换检索词。<span></ul>";
          }
          $resultContent.innerHTML = BTN + str;
        });
      }
    });
    $(document).on('click', '#local-search-close', function() {
      $('#local-search-input').val('');
      $('#local-search-result').html('');
    });
  }
  
  var getSearchFile = function(path){
      // var path = "/search.xml";
      searchFunc(path, 'local-search-input', 'local-search-result');
  }