/* μlogger
 *
 * Copyright(C) 2017 Bartek Fabiszewski (www.fabiszewski.net)
 *
 * This is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

// openlayers 3+
var map;
var layerTrack;
var layerMarkers;
var selectedLayer;
var olStyles;
var loadedAPI = 'openlayers';

function init() {

  addCss('css/ol.css', 'ol_css');

  var controls = [
    new ol.control.Zoom(),
    new ol.control.Rotate(),
    new ol.control.ScaleLine(),
    new ol.control.ZoomToExtent({ label: getExtentImg() }),
  ];

  var view = new ol.View({
    center: ol.proj.fromLonLat([init_longitude, init_latitude]),
    zoom: 8
  });

  map = new ol.Map({
    target: 'map-canvas',
    controls: controls,
    view: view
  });

  // default layer: OpenStreetMap
  var osm = new ol.layer.Tile({
    name: 'OpenStreetMap',
    visible: true,
    source: new ol.source.OSM()
  });
  map.addLayer(osm);
  selectedLayer = osm;

  // add extra layers
  for (var layerName in ol_layers) {
    if (ol_layers.hasOwnProperty(layerName)) {
      var layerUrl = ol_layers[layerName];
      var ol_layer = new ol.layer.Tile({
        name: layerName,
        visible: false,
        source: new ol.source.XYZ({
          url: layerUrl
        })
      });
      map.addLayer(ol_layer);
    }
  }

  // init layers
  var lineStyle = new ol.style.Style({
    stroke: new ol.style.Stroke({
      color: hexToRGBA(strokeColor, strokeOpacity),
      width: strokeWeight
    })
  });
  layerTrack = new ol.layer.Vector({
    name: 'Track',
    type: 'data',
    source: new ol.source.Vector(),
    style: lineStyle
  });
  layerMarkers = new ol.layer.Vector({
    name: 'Markers',
    type: 'data',
    source: new ol.source.Vector()
  });
  map.addLayer(layerTrack);
  map.addLayer(layerMarkers);

  // styles
  olStyles = {};
  var iconRed = new ol.style.Icon({
    anchor: [ 0.5, 1 ],
    src: 'images/marker-red.png'
  });
  var iconGreen = new ol.style.Icon({
    anchor: [ 0.5, 1 ],
    src: 'images/marker-green.png'
  });
  var iconWhite = new ol.style.Icon({
    anchor: [ 0.5, 1 ],
    opacity: 0.7,
    src: 'images/marker-white.png'
  });
  var iconGold = new ol.style.Icon({
    anchor: [ 0.5, 1 ],
    src: 'images/marker-gold.png'
  });
  olStyles['red'] = new ol.style.Style({
    image: iconRed
  });
  olStyles['green'] = new ol.style.Style({
    image: iconGreen
  });
  olStyles['white'] = new ol.style.Style({
    image: iconWhite
  });
  olStyles['gold'] = new ol.style.Style({
    image: iconGold
  });

  // popups
  var popupContainer = document.createElement('div');
  popupContainer.id = 'popup';
  popupContainer.className = 'ol-popup';
  document.getElementsByTagName('body')[0].appendChild(popupContainer);
  var popupCloser = document.createElement('a');
  popupCloser.id = 'popup-closer';
  popupCloser.className = 'ol-popup-closer';
  popupCloser.href = '#';
  popupContainer.appendChild(popupCloser);
  var popupContent = document.createElement('div');
  popupContent.id = 'popup-content';
  popupContainer.appendChild(popupContent);

  var popup = new ol.Overlay({
    element: popupContainer,
    autoPan: true,
    autoPanAnimation: {
      duration: 250
    }
  });

  popupCloser.onclick = function() {
    popup.setPosition(undefined);
    popupCloser.blur();
    return false;
  };

  // add click handler to map to show popup
  map.on('click', function(e) {
    var coordinate = e.coordinate;
    var feature = map.forEachFeatureAtPixel(e.pixel,
      function(feature, layer) {
        if (layer.get('name') == 'Markers') {
          return feature;
        }
      });
    if (feature) {
      var p = feature.get('p');
      var i = feature.getId();
      var posLen = feature.get('posLen');
      // popup show
      popup.setPosition(coordinate);
      popupContent.innerHTML = getPopupHtml(p, i, posLen);
      map.addOverlay(popup);
      if (document.getElementById('bottom').style.display == 'block') {
        var index = 0;
        for (var key in altitudes) {
          if (altitudes.hasOwnProperty(key) && key == i) {
            chart.setSelection([{ row: index, column: null }]);
            break;
          }
          index++;
        }
      }
    } else {
      // popup destroy
      popup.setPosition(undefined);
    }
  });

  // change mouse cursor when over marker
  map.on('pointermove', function(e) {
    var hit = map.forEachFeatureAtPixel(e.pixel, function(feature, layer) {
      if (layer.get('name') == 'Markers') {
        return true;
      } else {
        return false;
      }
    });
    if (hit) {
      this.getTargetElement().style.cursor = 'pointer';
    } else {
      this.getTargetElement().style.cursor = '';
    }
  });

  // layer switcher
  var switcher = document.createElement('div');
  switcher.id = 'switcher';
  switcher.className = 'ol-control';
  document.getElementsByTagName('body')[0].appendChild(switcher);
  var switcherContent = document.createElement('div');
  switcherContent.id = 'switcher-content';
  switcherContent.className = 'ol-layerswitcher';
  switcher.appendChild(switcherContent);

  map.getLayers().forEach(function (layer) {
    var layerLabel = document.createElement('label');
    layerLabel.innerHTML = layer.get('name');
    switcherContent.appendChild(layerLabel);

    var layerRadio = document.createElement('input');
    if (layer.get('type') === 'data') {
      layerRadio.type = 'checkbox';
      layerLabel.className = 'ol-datalayer';
    } else {
      layerRadio.type = 'radio';
    }
    layerRadio.name = 'layer';
    layerRadio.value = layer.get('name');
    layerRadio.onclick = switchLayer;
    if (layer.getVisible()) {
      layerRadio.checked = true;
    }
    layerLabel.insertBefore(layerRadio, layerLabel.childNodes[0]);
  });

  function switchLayer() {
    var layerName = this.value;
    map.getLayers().forEach(function (layer) {
      if (layer.get('name') === layerName) {
        if (layer.get('type') === 'data') {
          if (layer.getVisible()) {
            layer.setVisible(false);
          } else {
            layer.setVisible(true);
          }
        } else {
          selectedLayer.setVisible(false);
          selectedLayer = layer;
          layer.setVisible(true);
        }
        return;
      }
    });
  };

  var switcherButton = document.createElement('button');
  var layerImg = document.createElement('img');
  layerImg.src = 'images/layers.svg';
  layerImg.style.width = '60%';
  switcherButton.appendChild(layerImg);

  var switcherHandle = function() {
    var el = document.getElementById('switcher');
    if (el.style.display === 'block') {
      el.style.display = 'none';
    } else {
      el.style.display = 'block';
    }
  };

  switcherButton.addEventListener('click', switcherHandle, false);
  switcherButton.addEventListener('touchstart', switcherHandle, false);

  var element = document.createElement('div');
  element.className = 'ol-switcher-button ol-unselectable ol-control';
  element.appendChild(switcherButton);

  var switcherControl = new ol.control.Control({
      element: element
  });
  map.addControl(switcherControl);
}

function cleanup() {
  map = undefined;
  layerTrack = undefined;
  layerMarkers = undefined;
  selectedLayer = undefined;
  olStyles = undefined;
  removeElementById('popup');
  removeElementById('switcher');
  document.getElementById('map-canvas').innerHTML = '';
}


function displayTrack(xml, update) {
  altitudes = {};
  var totalMeters = 0;
  var totalSeconds = 0;
  var points = [];
  var positions = xml.getElementsByTagName('position');
  var posLen = positions.length;
  for (var i = 0; i < posLen; i++) {
    var p = parsePosition(positions[i], i);
    totalMeters += p.distance;
    totalSeconds += p.seconds;
    p.totalMeters = totalMeters;
    p.totalSeconds = totalSeconds;
    // set marker
    setMarker(p, i, posLen);
    // update polyline
    var point = ol.proj.fromLonLat([p.longitude, p.latitude]);
    points.push(point);
  }
  var lineString = new ol.geom.LineString(points);

  var lineFeature = new ol.Feature({
    geometry: lineString,
  });

  layerTrack.getSource().addFeature(lineFeature);

  var extent = layerTrack.getSource().getExtent();

  map.getControls().forEach(function (el) {
    if (el instanceof ol.control.ZoomToExtent) {
      map.removeControl(el);
    }
  });

  if (update) {
    map.getView().fit(extent);
    var zoom = map.getView().getZoom();
    if (zoom > 20) {
      map.getView().setZoom(20);
      extent = map.getView().calculateExtent(map.getSize());
    }
  }

  var zoomToExtentControl = new ol.control.ZoomToExtent({
    extent: extent,
    label: getExtentImg()
  });
  map.addControl(zoomToExtentControl);

  updateSummary(p.timestamp, totalMeters, totalSeconds);
  if (p.tid != trackid) {
    trackid = p.tid;
    setTrack(trackid);
  }
  if (document.getElementById('bottom').style.display == 'block') {
    // update altitudes chart
    chart.clearChart();
    displayChart();
  }
}

function clearMap() {
  if (layerTrack) {
    layerTrack.getSource().clear();
  }
  if (layerMarkers) {
    layerMarkers.getSource().clear();
  }
}

function setMarker(p, i, posLen) {
  // marker
  var marker = new ol.Feature({
    geometry: new ol.geom.Point(ol.proj.fromLonLat([p.longitude, p.latitude]))
  });

  if (latest == 1) {
    var iconStyle = olStyles['red'];
  } else if (i == 0) {
    var iconStyle = olStyles['green'];
  } else if (i == posLen - 1) {
    var iconStyle = olStyles['red'];
  } else {
    var iconStyle = olStyles['white'];
  }
  marker.setStyle(iconStyle);
  marker.setId(i);
  marker.set('p', p);
  marker.set('posLen', posLen);
  layerMarkers.getSource().addFeature(marker);
}

function addChartEvent(chart, data) {
  google.visualization.events.addListener(chart, 'select', function () {
    var selection = chart.getSelection()[0];
    if (selection) {
      var id = data.getValue(selection.row, 0) - 1;
      var marker = layerMarkers.getSource().getFeatureById(id);
      var url = marker.get('src');
      var initStyle = marker.getStyle();
      var iconStyle = olStyles['gold'];
      marker.setStyle(iconStyle);
      altTimeout = setTimeout(function () { marker.setStyle(initStyle); }, 2000);
    }
  });
}

//20.597985430276808,52.15547181298076,21.363595171488573,52.33750879522563
function getBounds() {
  var extent = map.getView().calculateExtent(map.getSize());
  var bounds = ol.proj.transformExtent(extent, 'EPSG:900913', 'EPSG:4326');
  var lon_sw = bounds[0];
  var lat_sw = bounds[1];
  var lon_ne = bounds[2];
  var lat_ne = bounds[3];
  return [lon_sw, lat_sw, lon_ne, lat_ne];
}

function zoomToExtent() {
  map.getView().fit(layerMarkers.getSource().getExtent())
}

function zoomToBounds(b) {
  var bounds = ol.proj.transformExtent(b, 'EPSG:4326', 'EPSG:900913');
  map.getView().fit(bounds);
}

function updateSize() {
  map.updateSize();
}

function getExtentImg() {
  var extentImg = document.createElement('img');
  extentImg.src = 'images/extent.svg';
  extentImg.style.width = '60%';
  return extentImg;
}