//
  // styling of input fields
//

var inputElements = document.querySelectorAll('input.tlon-input');
for (var i = 0; i < inputElements.length; i++) {
  //listen for changes in input
  inputElements[i].addEventListener('input', function() {
    // if input has a value do this
    if (this.value) {
      var inputContainer = this.parentNode;
      var validInputs = inputContainer.querySelectorAll('input.tlon-input:valid');
      var inputs = inputContainer.querySelectorAll('input.tlon-input');
      if (validInputs.length !== 0) {
        // has valid input
        for (var i = 0; i < validInputs.length; i++) {
          if (this.classList.contains('is-valid') == false ) {
            validInputs[i].parentNode.classList.add('has-valid-input');
          }
        }
      } else {
        // doesn't have valid input
        for (var i = 0; i < inputs.length; i++) {
          inputs[i].parentNode.classList.remove('has-valid-input');
        }
      }
    } else {
      this.parentNode.classList.remove('has-valid-input');
    }
  });
}

//
  // toggling of navigation menus
//

var toggleMainNav = document.getElementById('js-main-nav-toggle');
if (toggleMainNav !== null) {
  toggleMainNav.onclick = function() {
    document.body.classList.toggle('has-active-main-nav');
  }
}

var toggleContentNav = document.getElementById('js-content-nav-toggle');
if (toggleContentNav !== null) {
  toggleContentNav.onclick = function() {
    document.body.classList.toggle('has-active-content-nav');
  }
}

/*function initToggleMenu() {
  var menu = document.querySelector(".menu");
  var menuIcon = document.querySelector(".menu-icon");
  var page = document.querySelector(".page");
  menuIcon.addEventListener("click", function() {
    menu.classList.toggle("menu-hidden");
    page.classList.toggle("page-without-menu");
  });
}*/

//
  // hotkeys
//

function initHotKeys() {

  var bodyEl = document.body;
  var searchInput = document.getElementById('search');

  document.addEventListener('keydown', function (event) {
      if (event.defaultPrevented) {
          return;
      }

      var key = event.key || event.keyCode;

      // ESC to close search window
      if (key === 'Escape' || key === 'Esc' || key === 27) {
        document.body.classList.remove('has-active-search-window');
        console.log('esc');
      }

      // / to close toggle window
      if (key === '/' || key === 'Period' || key === 58) {
        event.preventDefault();
        document.body.classList.toggle('has-active-search-window');
        if (bodyEl.classList.contains('has-active-search-window')) {
          searchInput.focus();
        }
      }

      //when search is active TAB puts search input into focus
      if (bodyEl.classList.contains('has-active-search-window')) {
        if (key === 'Tab' || key === 'Tab' || key === 9) {
          searchInput.focus();
        }
      }
  });
};

//
  // search functionality
//

function debounce(func, wait) {
  var timeout;

  return function () {
    var context = this;
    var args = arguments;
    clearTimeout(timeout);

    timeout = setTimeout(function () {
      timeout = null;
      func.apply(context, args);
    }, wait);
  };
}

// Taken from mdbook
// The strategy is as follows:
// First, assign a value to each word in the document:
//  Words that correspond to search terms (stemmer aware): 40
//  Normal words: 2
//  First word in a sentence: 8
// Then use a sliding window with a constant number of words and count the
// sum of the values of the words within the window. Then use the window that got the
// maximum sum. If there are multiple maximas, then get the last one.
// Enclose the terms in <b>.
function makeTeaser(body, terms) {
  console.log("make teaser");
  var TERM_WEIGHT = 40;
  var NORMAL_WORD_WEIGHT = 2;
  var FIRST_WORD_WEIGHT = 8;
  //var TEASER_MAX_WORDS = 17;
  var TEASER_MAX_CHARS = 63;


  var stemmedTerms = terms.map(function (w) {
    return elasticlunr.stemmer(w.toLowerCase());
  });

    console.log(stemmedTerms);
  // create array with full word + partial Words (smallest fragment is 2 characters)
  // first iteration is full word, then next is subset of the original word
  /*var stemmedTerms = [];
  for (var i = terms[0].length; i>=2; i--) {
      stemmedTerms.push(terms[0].substring(0,i));
  }
  console.log(stemmedTerms);*/
  var termFound = false;
  var index = 0;
  var weighted = []; // contains elements of ["word", weight, index_in_document]

  // split in sentences, then words
  var sentences = body.toLowerCase().split(". ");

  for (var i in sentences) {
    var words = sentences[i].split(" ");
    var value = FIRST_WORD_WEIGHT;

    for (var j in words) {
      var word = words[j];

      if (word.length > 0) {
        for (var k in stemmedTerms) {
          if (elasticlunr.stemmer(word).startsWith(stemmedTerms[k])) {
            value = TERM_WEIGHT;
            termFound = true;
          }
        }
        weighted.push([word, value, index]);
        value = NORMAL_WORD_WEIGHT;
      }

      index += word.length;
      index += 1;  // ' ' or '.' if last word in sentence
    }

    index += 1;  // because we split at a two-char boundary '. '
  }

  if (weighted.length === 0) {
    return body;
  }

  var windowWeights = [];
  var windowSize = 0;

  // loop over words (weighted) till max chars is reached adding a counter to windowSize every time a new word has passed
  var sumChars = 0;
  for (var i = 0; i < weighted.length; i++) {
    sumChars += weighted[i][0].length;
    if (sumChars <= TEASER_MAX_CHARS) {
      windowSize++;
    }
  }

  // We add a window with all the weights first
  var curSum = 0;
  for (var i = 0; i < windowSize; i++) {
    curSum += weighted[i][1];
  }
  windowWeights.push(curSum);

  for (var i = 0; i < weighted.length - windowSize; i++) {
    curSum -= weighted[i][1];
    curSum += weighted[i + windowSize][1];
    windowWeights.push(curSum);
  }

  // If we didn't find the term, just pick the first window
  var maxSumIndex = 0;
  if (termFound) {
    var maxFound = 0;
    // backwards
    for (var i = windowWeights.length - 1; i >= 0; i--) {
      if (windowWeights[i] > maxFound) {
        maxFound = windowWeights[i];
        maxSumIndex = i;
      }
    }
  }

  var teaser = [];
  var startIndex = weighted[maxSumIndex][2];
  for (var i = maxSumIndex; i < maxSumIndex + windowSize; i++) {
    var word = weighted[i];
    if (startIndex < word[2]) {
      // missing text from index to start of `word`
      teaser.push(body.substring(startIndex, word[2]));
      startIndex = word[2];
    }

    // add dark color around search terms
    if (word[1] === TERM_WEIGHT) {
      teaser.push("<span class='gray70'>");
    }
    startIndex = word[2] + word[0].length;
    teaser.push(body.substring(word[2], startIndex));

    if (word[1] === TERM_WEIGHT) {
      teaser.push("</span>");
    }
  }
  teaser.push("…");
  return teaser.join("");
}

function formatSearchResultTitle(path) {
  var pathArray = path.split( '/' );

  // first directory is in 4th element of split path array
  var firstPartTitle = pathArray[3];

  // last directory is in 2nd to last element of array
  var lastPartTitle = pathArray[pathArray.length-2].replace(/-/g,' ');

  var fullTitle = firstPartTitle + '<span class="gray90">' + ' / ' + lastPartTitle + '</span>';

  return fullTitle;
}

function formatSearchResultItem(item, terms) {
  var li = document.createElement("li");
  var createA = document.createElement("a");
  li.appendChild(createA);
  var teaserTitle = formatSearchResultTitle(item.ref);
  li.classList.add("search-results__item");
  var hrefA = item.ref;
  createA.setAttribute('href', hrefA);
  createA.setAttribute('class','no-underline block pl6 pv2');
  createA.innerHTML = `<span class="fs45 capitalize gray30">${teaserTitle}</span>`;
  createA.innerHTML += `<div class="fs35 gray30">${makeTeaser(item.doc.body, terms)}</div>`;
  return li;
}

function initSearch() {
  console.log("init search");
  var searchInput = document.getElementById("search");

  if (!searchInput) {
    return;
  }

  var searchResults = document.querySelector(".search-results");
  var searchResultsHeader = document.querySelector(".search-results__header");
  var searchResultsItems = document.querySelector(".search-results__items");
  var MAX_ITEMS = 200;

  var options = {
    bool: "AND",
    expand: true,
    fields: {
      title: {boost: 2},
      body: {boost: 1},
    }
  };
  var currentTerm = "";
  var index = elasticlunr.Index.load(window.searchIndex);

  // toggle search window
  var toggleSearchWindow = document.getElementById('js-search-window-toggle');
  var bodyEl = document.body;
  var searchOverlay = document.getElementById('search-overlay');
  var searchWindow = document.getElementById('search-window');
  var searchActive = bodyEl.classList.contains('has-active-search-window');
  if (toggleSearchWindow !== null) {
    toggleSearchWindow.onclick = function() {
      //activate search
      bodyEl.classList.toggle('has-active-search-window');
      //put input in focus when activating search
      searchInput.focus();
      searchInput.value = "";
      searchResultsHeader.value = "";
      searchResults.style.display = searchInput.value.trim() === "" ? "none" : "block";
    }
    searchOverlay.addEventListener('click', function(e){
    	if (!searchWindow.contains(e.target)){
        bodyEl.classList.toggle('has-active-search-window');
      }
    })
  }

  // when typing
  searchInput.addEventListener("keyup", debounce(function() {
    searchResultsHeader.value = "";

    var term = searchInput.value.trim();

    /*
    //removed to fix: a state where there’s a valid search term, but no results

    if (term === currentTerm || !index) {
      return;
    }*/

    searchResults.style.display = term === "" ? "none" : "block";
    searchResults.style.overflowY = term === "" ? "hidden" : "scroll";
    searchResultsItems.innerHTML = "";
    if (term === "") {
      return;
    }

    // change query in order to make partial words work

    var results = index.search(term, options).filter(function (r) {
      return r.doc.body !== "";
    });
    if (results.length === 0) {
      searchResultsHeader.innerText = `No search results for '${term}'.`;
      return;
    }

    currentTerm = term;
      searchResultsHeader.innerText = `${results.length} search results for '${term}':`;
    for (var i = 0; i < Math.min(results.length, MAX_ITEMS); i++) {
      if (!results[i].doc.body) {
        continue;
      }
      searchResultsItems.appendChild(formatSearchResultItem(results[i], term.split(" ")));
    }
  }, 150));
}

if (document.readyState === "complete" ||
    (document.readyState !== "loading" && !document.documentElement.doScroll)
) {
  initToggleSearchWindow();
} else {
  document.addEventListener("DOMContentLoaded", function () {
    initSearch();
    initHotKeys();
  });
}