'use strict';
/*global angular: false, Highcharts: false */

angular.module('highcharts-ng', [])
  .factory('highchartsNGUtils', function () {

    return {

      //IE8 support
      indexOf: function (arr, find, i /*opt*/) {
        if (i === undefined) i = 0;
        if (i < 0) i += arr.length;
        if (i < 0) i = 0;
        for (var n = arr.length; i < n; i++)
          if (i in arr && arr[i] === find)
            return i;
        return -1;
      },


      prependMethod: function (obj, method, func) {
        var original = obj[method];
        obj[method] = function () {
          var args = Array.prototype.slice.call(arguments);
          func.apply(this, args);
          if (original) {
            return original.apply(this, args);
          } else {
            return;
          }

        };
      },

      deepExtend: function deepExtend(destination, source) {
        //Slightly strange behaviour in edge cases (e.g. passing in non objects)
        //But does the job for current use cases.
        if (angular.isArray(source)) {
          destination = angular.isArray(destination) ? destination : [];
          for (var i = 0; i < source.length; i++) {
            destination[i] = deepExtend(destination[i] || {}, source[i]);
          }
        } else if (angular.isObject(source)) {
          for (var property in source) {
            destination[property] = deepExtend(destination[property] || {}, source[property]);
          }
        } else {
          destination = source;
        }
        return destination;
      }
    };

  }).directive('highchart', function (highchartsNGUtils) {

    // acceptable shared state
    var seriesId = 0;
    var ensureIds = function (series) {
      var changed = false;
      angular.forEach(series, function(s) {
        if (!angular.isDefined(s.id)) {
          s.id = 'series-' + seriesId++;
          changed = true;
        }
      });
      return changed;
    };

    // immutable
    var axisNames = [ 'xAxis', 'yAxis' ];

    var getMergedOptions = function (scope, element, config) {
      var mergedOptions = {};

      var defaultOptions = {
        chart: {
          events: {}
        },
        title: {},
        subtitle: {},
        series: [],
        credits: {},
        plotOptions: {},
        navigator: {enabled: false}
      };

      if (config.options) {
        mergedOptions = highchartsNGUtils.deepExtend(defaultOptions, config.options);
      } else {
        mergedOptions = defaultOptions;
      }
      mergedOptions.chart.renderTo = element[0];

      angular.forEach(axisNames, function(axisName) {
        if(angular.isDefined(config[axisName])) {
          mergedOptions[axisName] = angular.copy(config[axisName]);

          if(angular.isDefined(config[axisName].currentMin) ||
              angular.isDefined(config[axisName].currentMax)) {

            highchartsNGUtils.prependMethod(mergedOptions.chart.events, 'selection', function(e){
              var thisChart = this;
              if (e[axisName]) {
                scope.$apply(function () {
                  scope.config[axisName].currentMin = e[axisName][0].min;
                  scope.config[axisName].currentMax = e[axisName][0].max;
                });
              } else {
                //handle reset button - zoom out to all
                scope.$apply(function () {
                  scope.config[axisName].currentMin = thisChart[axisName][0].dataMin;
                  scope.config[axisName].currentMax = thisChart[axisName][0].dataMax;
                });
              }
            });

            highchartsNGUtils.prependMethod(mergedOptions.chart.events, 'addSeries', function(e){
              scope.config[axisName].currentMin = this[axisName][0].min || scope.config[axisName].currentMin;
              scope.config[axisName].currentMax = this[axisName][0].max || scope.config[axisName].currentMax;
            });
          }
        }
      });

      if(config.title) {
        mergedOptions.title = config.title;
      }
      if (config.subtitle) {
        mergedOptions.subtitle = config.subtitle;
      }
      if (config.credits) {
        mergedOptions.credits = config.credits;
      }
      if(config.size) {
        if (config.size.width) {
          mergedOptions.chart.width = config.size.width;
        }
        if (config.size.height) {
          mergedOptions.chart.height = config.size.height;
        }
      }
      return mergedOptions;
    };

    var updateZoom = function (axis, modelAxis) {
      var extremes = axis.getExtremes();
      if(modelAxis.currentMin !== extremes.dataMin || modelAxis.currentMax !== extremes.dataMax) {
        axis.setExtremes(modelAxis.currentMin, modelAxis.currentMax, false);
      }
    };

    var processExtremes = function(chart, axis, axisName) {
      if(axis.currentMin || axis.currentMax) {
        chart[axisName][0].setExtremes(axis.currentMin, axis.currentMax, true);
      }
    };

    var chartOptionsWithoutEasyOptions = function (options) {
      return angular.extend({}, options, {data: null, visible: null});
    };

    return {
      restrict: 'EAC',
      replace: true,
      template: '<div></div>',
      scope: {
        config: '='
      },
      link: function (scope, element, attrs) {
        // We keep some chart-specific variables here as a closure
        // instead of storing them on 'scope'.

        // prevSeriesOptions is maintained by processSeries
        var prevSeriesOptions = {};

        var processSeries = function(series) {
          var i;
          var ids = [];

          if(series) {
            var setIds = ensureIds(series);
            if(setIds) {
              //If we have set some ids this will trigger another digest cycle.
              //In this scenario just return early and let the next cycle take care of changes
              return false;
            }

            //Find series to add or update
            angular.forEach(series, function(s) {
              ids.push(s.id);
              var chartSeries = chart.get(s.id);
              if (chartSeries) {
                if (!angular.equals(prevSeriesOptions[s.id], chartOptionsWithoutEasyOptions(s))) {
                  chartSeries.update(angular.copy(s), false);
                } else {
                  if (s.visible !== undefined && chartSeries.visible !== s.visible) {
                    chartSeries.setVisible(s.visible, false);
                  }
                  chartSeries.setData(angular.copy(s.data), false);
                }
              } else {
                chart.addSeries(angular.copy(s), false);
              }
              prevSeriesOptions[s.id] = chartOptionsWithoutEasyOptions(s);
            });

            //  Shows no data text if all series are empty
            if(scope.config.noData) {
              var chartContainsData = false;

              for(i = 0; i < series.length; i++) {
                if (series[i].data && series[i].data.length > 0) {
                  chartContainsData = true;

                  break;
                }
              }

              if (!chartContainsData) {
                chart.showLoading(scope.config.noData);
              } else {
                chart.hideLoading();
              }
            }
          }

          //Now remove any missing series
          for(i = chart.series.length - 1; i >= 0; i--) {
            var s = chart.series[i];
            if (highchartsNGUtils.indexOf(ids, s.options.id) < 0) {
              s.remove(false);
            }
          }

          return true;
        };

        // chart is maintained by initChart
        var chart = false;
        var initChart = function() {
          if (chart) chart.destroy();
          prevSeriesOptions = {};
          var config = scope.config || {};
          var mergedOptions = getMergedOptions(scope, element, config);
          var func = config.func || undefined;
          chart = config.useHighStocks ?
            new Highcharts.StockChart(mergedOptions, func) :
            new Highcharts.Chart(mergedOptions, func);
          for (var i = 0; i < axisNames.length; i++) {
            if (config[axisNames[i]]) {
              processExtremes(chart, config[axisNames[i]], axisNames[i]);
            }
          }
          if(config.loading) {
            chart.showLoading();
          }

        };
        initChart();


        scope.$watch('config.series', function (newSeries, oldSeries) {
          var needsRedraw = processSeries(newSeries);
          if(needsRedraw) {
            chart.redraw();
          }
        }, true);

        scope.$watch('config.title', function (newTitle) {
          chart.setTitle(newTitle, true);
        }, true);

        scope.$watch('config.subtitle', function (newSubtitle) {
          chart.setTitle(true, newSubtitle);
        }, true);

        scope.$watch('config.loading', function (loading) {
          if(loading) {
            chart.showLoading();
          } else {
            chart.hideLoading();
          }
        });

        scope.$watch('config.credits.enabled', function (enabled) {
          if (enabled) {
            chart.credits.show();
          } else if (chart.credits) {
            chart.credits.hide();
          }
        });

        scope.$watch('config.useHighStocks', function (useHighStocks, oldUseHighStocks) {
          if(useHighStocks === oldUseHighStocks) return;
          initChart();
        });

        angular.forEach(axisNames, function(axisName) {
          scope.$watch('config.' + axisName, function (newAxes, oldAxes) {
            if (newAxes === oldAxes) return;
            if(newAxes) {
              chart[axisName][0].update(newAxes, false);
              updateZoom(chart[axisName][0], angular.copy(newAxes));
              chart.redraw();
            }
          }, true);
        });
        scope.$watch('config.options', function (newOptions, oldOptions, scope) {
          //do nothing when called on registration
          if (newOptions === oldOptions) return;
          initChart();
          processSeries(scope.config.series);
          chart.redraw();
        }, true);

        scope.$watch('config.size', function (newSize, oldSize) {
          if(newSize === oldSize) return;
          if(newSize) {
            chart.setSize(newSize.width || undefined, newSize.height || undefined);
          }
        }, true);

        scope.$on('highchartsng.reflow', function () {
          chart.reflow();
        });

        scope.$on('$destroy', function() {
          if (chart) chart.destroy();
          element.remove();
        });

      }
    };
  });