/*
   * Flot plugin to order bars side by side.
   * 
   * Released under the MIT license by Benjamin BUFFET, 20-Sep-2010.
   *
   * This plugin is an alpha version.
   *
   * To activate the plugin you must specify the parameter "order" for the specific serie :
   *
   *  $.plot($("#placeholder"), [{ data: [ ... ], bars :{ order = null or integer }])
   *
   * If 2 series have the same order param, they are ordered by the position in the array;
   *
   * The plugin adjust the point by adding a value depanding of the barwidth
   * Exemple for 3 series (barwidth : 0.1) :
   *
   *          first bar décalage : -0.15
   *          second bar décalage : -0.05
   *          third bar décalage : 0.05
   *
   */
  
  (function($){
      function init(plot){
          var orderedBarSeries;
          var nbOfBarsToOrder;
          var borderWidth;
          var borderWidthInXabsWidth;
          var pixelInXWidthEquivalent = 1;
          var isHorizontal = false;
  
          /*
           * This method add shift to x values
           */
          function reOrderBars(plot, serie, datapoints){
              var shiftedPoints = null;
              
              if(serieNeedToBeReordered(serie)){                
                  checkIfGraphIsHorizontal(serie);
                  calculPixel2XWidthConvert(plot);
                  retrieveBarSeries(plot);
                  calculBorderAndBarWidth(serie);
                  
                  if(nbOfBarsToOrder >= 2){  
                      var position = findPosition(serie);
                      var decallage = 0;
                      
                      var centerBarShift = calculCenterBarShift();
  
                      if (isBarAtLeftOfCenter(position)){
                          decallage = -1*(sumWidth(orderedBarSeries,position-1,Math.floor(nbOfBarsToOrder / 2)-1)) - centerBarShift;
                      }else{
                          decallage = sumWidth(orderedBarSeries,Math.ceil(nbOfBarsToOrder / 2),position-2) + centerBarShift + borderWidthInXabsWidth*2;
                      }
  
                      shiftedPoints = shiftPoints(datapoints,serie,decallage);
                      datapoints.points = shiftedPoints;
                 }
             }
             return shiftedPoints;
          }
  
          function serieNeedToBeReordered(serie){
              return serie.bars != null
                  && serie.bars.show
                  && serie.bars.order != null;
          }
  
          function calculPixel2XWidthConvert(plot){
              var gridDimSize = isHorizontal ? plot.getPlaceholder().innerHeight() : plot.getPlaceholder().innerWidth();
              var minMaxValues = isHorizontal ? getAxeMinMaxValues(plot.getData(),1) : getAxeMinMaxValues(plot.getData(),0);
              var AxeSize = minMaxValues[1] - minMaxValues[0];
              pixelInXWidthEquivalent = AxeSize / gridDimSize;
          }
  
          function getAxeMinMaxValues(series,AxeIdx){
              var minMaxValues = new Array();
              for(var i = 0; i < series.length; i++){
                  minMaxValues[0] = series[i].data[0][AxeIdx];
                  minMaxValues[1] = series[i].data[series[i].data.length - 1][AxeIdx];
              }
              return minMaxValues;
          }
  
          function retrieveBarSeries(plot){
              orderedBarSeries = findOthersBarsToReOrders(plot.getData());
              nbOfBarsToOrder = orderedBarSeries.length;
          }
  
          function findOthersBarsToReOrders(series){
              var retSeries = new Array();
  
              for(var i = 0; i < series.length; i++){
                  if(series[i].bars.order != null && series[i].bars.show){
                      retSeries.push(series[i]);
                  }
              }
  
              return retSeries.sort(sortByOrder);
          }
  
          function sortByOrder(serie1,serie2){
              var x = serie1.bars.order;
              var y = serie2.bars.order;
              return ((x < y) ? -1 : ((x > y) ? 1 : 0));
          }
  
          function  calculBorderAndBarWidth(serie){
              borderWidth = serie.bars.lineWidth ? serie.bars.lineWidth  : 2;
              borderWidthInXabsWidth = borderWidth * pixelInXWidthEquivalent;
          }
          
          function checkIfGraphIsHorizontal(serie){
              if(serie.bars.horizontal){
                  isHorizontal = true;
              }
          }
  
          function findPosition(serie){
              var pos = 0
              for (var i = 0; i < orderedBarSeries.length; ++i) {
                  if (serie == orderedBarSeries[i]){
                      pos = i;
                      break;
                  }
              }
  
              return pos+1;
          }
  
          function calculCenterBarShift(){
              var width = 0;
  
              if(nbOfBarsToOrder%2 != 0)
                  width = (orderedBarSeries[Math.ceil(nbOfBarsToOrder / 2)].bars.barWidth)/2;
  
              return width;
          }
  
          function isBarAtLeftOfCenter(position){
              return position <= Math.ceil(nbOfBarsToOrder / 2);
          }
  
          function sumWidth(series,start,end){
              var totalWidth = 0;
  
              for(var i = start; i <= end; i++){
                  totalWidth += series[i].bars.barWidth+borderWidthInXabsWidth*2;
              }
  
              return totalWidth;
          }
  
          function shiftPoints(datapoints,serie,dx){
              var ps = datapoints.pointsize;
              var points = datapoints.points;
              var j = 0;           
              for(var i = isHorizontal ? 1 : 0;i < points.length; i += ps){
                  points[i] += dx;
                  //Adding the new x value in the serie to be abble to display the right tooltip value,
                  //using the index 3 to not overide the third index.
                  serie.data[j][3] = points[i];
                  j++;
              }
  
              return points;
          }
  
          plot.hooks.processDatapoints.push(reOrderBars);
  
      }
  
      var options = {
          series : {
              bars: {order: null} // or number/string
          }
      };
  
      $.plot.plugins.push({
          init: init,
          options: options,
          name: "orderBars",
          version: "0.2"
      });
  
  })(jQuery)