CodeMirror.validate = (function() {
  var GUTTER_ID = "CodeMirror-lint-markers";
  var SEVERITIES = /^(?:error|warning)$/;

  function showTooltip(e, content) {
    var tt = document.createElement("div");
    tt.className = "CodeMirror-lint-tooltip";
    tt.appendChild(content.cloneNode(true));
    document.body.appendChild(tt);

    function position(e) {
      if (!tt.parentNode) return CodeMirror.off(document, "mousemove", position);
      tt.style.top = (e.clientY - tt.offsetHeight - 5) + "px";
      tt.style.left = (e.clientX + 5) + "px";
    }
    CodeMirror.on(document, "mousemove", position);
    position(e);
    tt.style.opacity = 1;
    return tt;
  }
  function rm(elt) {
    if (elt.parentNode) elt.parentNode.removeChild(elt);
  }
  function hideTooltip(tt) {
    if (!tt.parentNode) return;
    if (tt.style.opacity == null) rm(tt);
    tt.style.opacity = 0;
    setTimeout(function() { rm(tt); }, 600);
  }

  function LintState(cm, options, hasGutter) {
    this.marked = [];
    this.options = options;
    this.timeout = null;
    this.hasGutter = hasGutter;
    this.onMouseOver = function(e) { onMouseOver(cm, e); };
  }

  function parseOptions(options) {
    if (options instanceof Function) return {getAnnotations: options};
    else if (!options || !options.getAnnotations) throw new Error("Required option 'getAnnotations' missing (lint addon)");
    return options;
  }

  function clearMarks(cm) {
    var state = cm._lintState;
    if (state.hasGutter) cm.clearGutter(GUTTER_ID);
    for (var i = 0; i < state.marked.length; ++i)
      state.marked[i].clear();
    state.marked.length = 0;
  }

  function makeMarker(labels, severity, multiple) {
    var marker = document.createElement("div"), inner = marker;
    marker.className = "CodeMirror-lint-marker-" + severity;
    if (multiple) {
      inner = marker.appendChild(document.createElement("div"));
      inner.className = "CodeMirror-lint-marker-multiple";
    }

    var tooltip;
    CodeMirror.on(inner, "mouseover", function(e) { tooltip = showTooltip(e, labels); });
    CodeMirror.on(inner, "mouseout", function() { if (tooltip) hideTooltip(tooltip); });

    return marker;
  }

  function getMaxSeverity(a, b) {
    if (a == "error") return a;
    else return b;
  }

  function groupByLine(annotations) {
    var lines = [];
    for (var i = 0; i < annotations.length; ++i) {
      var ann = annotations[i], line = ann.from.line;
      (lines[line] || (lines[line] = [])).push(ann);
    }
    return lines;
  }

  function annotationTooltip(ann) {
    var severity = ann.severity;
    if (!SEVERITIES.test(severity)) severity = "error";
    var tip = document.createElement("div");
    tip.className = "CodeMirror-lint-message-" + severity;
    tip.appendChild(document.createTextNode(ann.message));
    return tip;
  }

  function startLinting(cm) {
	  var state = cm._lintState, options = state.options;
	  if (options.async)
		  options.getAnnotations(cm, updateLinting, options);
	  else
		 updateLinting(cm, options.getAnnotations(cm.getValue()));
  }
  
  function updateLinting(cm, annotationsNotSorted) {
    clearMarks(cm);
    var state = cm._lintState, options = state.options;

    var annotations = groupByLine(annotationsNotSorted);

    for (var line = 0; line < annotations.length; ++line) {
      var anns = annotations[line];
      if (!anns) continue;

      var maxSeverity = null;
      var tipLabel = state.hasGutter && document.createDocumentFragment();

      for (var i = 0; i < anns.length; ++i) {
        var ann = anns[i];
        var severity = ann.severity;
        if (!SEVERITIES.test(severity)) severity = "error";
        maxSeverity = getMaxSeverity(maxSeverity, severity);

	if (options.formatAnnotation) ann = options.formatAnnotation(ann);
        if (state.hasGutter) tipLabel.appendChild(annotationTooltip(ann));

        if (ann.to) state.marked.push(cm.markText(ann.from, ann.to, {
          className: "CodeMirror-lint-span-" + severity,
          __annotation: ann
        }));
      }

      if (state.hasGutter)
        cm.setGutterMarker(line, GUTTER_ID, makeMarker(tipLabel, maxSeverity, anns.length > 1));
    }
  }

  function onChange(cm) {
    var state = cm._lintState;
    clearTimeout(state.timeout);
    state.timeout = setTimeout(function(){startLinting(cm);}, state.options.delay || 500);
  }

  function popupSpanTooltip(ann, e) {
    var tooltip = showTooltip(e, annotationTooltip(ann));
    var target = e.target || e.srcElement;
    CodeMirror.on(target, "mouseout", hide);
    function hide() {
      CodeMirror.off(target, "mouseout", hide);
      hideTooltip(tooltip);
    }
  }

  // When the mouseover fires, the cursor might not actually be over
  // the character itself yet. These pairs of x,y offsets are used to
  // probe a few nearby points when no suitable marked range is found.
  var nearby = [0, 0, 0, 5, 0, -5, 5, 0, -5, 0];

  function onMouseOver(cm, e) {
    if (!/\bCodeMirror-lint-span-/.test((e.target || e.srcElement).className)) return;
    for (var i = 0; i < nearby.length; i += 2) {
      var spans = cm.findMarksAt(cm.coordsChar({left: e.clientX + nearby[i],
                                                top: e.clientY + nearby[i + 1]}));
      for (var j = 0; j < spans.length; ++j) {
        var span = spans[j], ann = span.__annotation;
        if (ann) return popupSpanTooltip(ann, e);
      }
    }
  }

  CodeMirror.defineOption("lintWith", false, function(cm, val, old) {
    if (old && old != CodeMirror.Init) {
      clearMarks(cm);
      cm.off("change", onChange);
      CodeMirror.off(cm.getWrapperElement(), "mouseover", cm._lintState.onMouseOver);
      delete cm._lintState;
    }
    
    if (val) {
      var gutters = cm.getOption("gutters"), hasLintGutter = false;
      for (var i = 0; i < gutters.length; ++i) if (gutters[i] == GUTTER_ID) hasLintGutter = true;
      var state = cm._lintState = new LintState(cm, parseOptions(val), hasLintGutter);
      cm.on("change", onChange);
      CodeMirror.on(cm.getWrapperElement(), "mouseover", state.onMouseOver);
      startLinting(cm);
    }
  });
})();
