// restdb.io query handler
var restDB = (function() {

  var 
    api = 'https://sitepoint-fbbf.restdb.io/rest/',
    APIkey = '597dd2c7a63f5e835a5df8c4';
  
  function query(url, callback) {
    
    var timeout, xhr = new XMLHttpRequest();
    xhr.open('GET', api + url);
    xhr.setRequestHeader('x-apikey', APIkey);
    xhr.setRequestHeader('content-type', 'application/json');
    xhr.setRequestHeader('cache-control', 'no-cache');
    
    // response
    xhr.onreadystatechange = function() {
			if (xhr.readyState !== 4) return;
			var err = (xhr.status !== 200), data = null;
      clearTimeout(timeout);
			if (!err) {
				try {
					data = JSON.parse(xhr.response);
				}
				catch(e) {
          err = true;
					data = xhr.response || null;
				}
			}
			callback(err, data);
		};
    
    // timeout
    timeout = setTimeout(function() {
      xhr.abort();
      callback(true, null);
    }, 10000);
    
    xhr.send();
    
  }

  return {
    query: query
  };

})();

// main application
(function() {
  
  var 
    form = id('search'),
    q = id('q'),
    results = id('results'),
    none = id('none'),
    running = id('running');
  
  show(none);
  
  // form submit event
  form.addEventListener('submit', function(e) {
    
    // stop submit
    e.preventDefault();
    
    // get query
    var qv = q.value.replace(/\s+/g, ' ').trim();
    if (!qv) return;
    
    // run query
    show(running);
    
    // run query
    restDB.query(
      '/content?' + 
      'q={ "$or": [' +
      '{ "title": {"$regex": "' + qv + '"} }, ' + 
      '{ "body": {"$regex": "' + qv + '"} }' + 
      ']}&' +           
      'h={ "$fields": { "slug": 1, "title": 1, "published": 1 } }',
    showResult);
    
  });
  
  
  // show search results
  function showResult(err, data) {
    
    if (err || !data || !data.length) {
      // error or no results
      show(none);
    }
    else {
      // empty results
      while (results.lastChild) results.removeChild(results.lastChild);
      
      // add results to list
      var r, page, li, a;
      for (r = 0; r < data.length; r++) {
        
        page = data[r];
        
        a = document.createElement('a');
        a.href = 'https://www-sitepoint-fbbf.restdb.io/' + page.slug;
        a.textContent = page.title + (page.published ? '' : ' [draft]');
        
        li = document.createElement('li');
        li.appendChild(a);
        
        results.appendChild(li);
      }
      
      show(results);
      
    }
    
  }
  
  // get element
  function id(id) {
    return document.getElementById(id);
  }
  
  // show and hide nodes
  function show(node) {
    s(results);
    s(none);
    s(running);

    function s(item) {
      item.style.display = (node === item ? 'block' : 'none');
    }
  }
  
})();