// Entry object
function entry(data){
    this.id=ko.observable(ko.utils.unwrapObservable(data.id));
    this.value_date=ko.observable(ko.utils.unwrapObservable(data.value_date));
    this.operation_date=ko.observable(ko.utils.unwrapObservable(data.operation_date));
    this.label=ko.observable(ko.utils.unwrapObservable(data.label));
    this.value=ko.observable(ko.utils.unwrapObservable(data.value));
    this.account_id=ko.observable(ko.utils.unwrapObservable(data.account_id));
    this.sold=ko.observable(ko.utils.unwrapObservable(data.sold));
    this.pointedsold=ko.observable(ko.utils.unwrapObservable(data.pointedsold));
    this.category=ko.observable(ko.utils.unwrapObservable(data.category));
}

// Util function to show a message in message placeholder.
function message(alertType, title, message) {
  $(".alert").alert('close');
  $("#message-placeholder").append('<div class="alert alert-' + alertType + '"><button type="button" class="close" data-dismiss="alert">&times;</button><h4>' + title + '</h4><strong>' + message + '</strong></div>');
}

var ListViewModel = function() {
    var self = this;

    // Account store and selection
    self.account = ko.observable();
    self.accounts = ko.observableArray([]);

    // Month store and selection
    self.months = ko.observableArray();
    self.month = ko.observable();

    // Entry store and selection
    self.entries = ko.observableArray([]);
    self.selectedItem = ko.observable();

    // Placeholder for saved value to cancel entry edition
    self.savedItem = null;

    // Placeholder for entry to remove to be available in modal function "yes" click callback
    self.itemToRemove = ko.observable();

    // Returns the data for the categories by summing values with same category
    self.expenseCategoriesChart = ko.computed(function() {
      var entries=ko.utils.unwrapObservable(self.entries);

      // First pass: get sum values for each category.
      var chartValuesTmp = {};
      $.each(entries, function(index, entry) {
        var category = entry.category();
        var value = entry.value() ? Number(entry.value()) : null;

        if(category && value && value < 0.0) {
          var oldValue = 0.0;

          if(chartValuesTmp[category]) {
            oldValue = chartValuesTmp[category];
          }

          chartValuesTmp[category] = oldValue - value
        }
      });
 
      // Second pass: transform to an array readable by jqplot.
      var chartValues = [];
      $.each(chartValuesTmp, function(key, value) {
        chartValues.push([key, value]);
      });

      return chartValues;
    });

    // Return the data for the sold chart.
    self.entriesChart = ko.computed(function() {
      // We assume that entries are sorted by value date descending.
      var entries = ko.utils.unwrapObservable(self.entries).slice().reverse();

      // First pass: get open, high, low and close values for each day.
      var chartValuesTmp = {};
      $.each(entries, function(index, entry) {
        //var date = entry.value_date() ? entry.value_date().toString() : null;
        var date = entry.value_date();
        var value = entry.value ? Number(entry.value()) : null;

        if(date && value) {
          var values = {};

          var sold = Number(entry.sold());
          var open = Number((sold - value).toFixed(2));

          values['open'] = open;
          values['high'] = sold > open ? sold : open;
          values['low'] = sold < open ? sold : open;
          values['close'] = sold;

          if(chartValuesTmp[date]) {
            var oldValues = chartValuesTmp[date];

            if(oldValues['high'] > values['high']) {
              values['high'] = oldValues['high'];
            }

            if(oldValues['low'] < values['low']) {
              values['low'] = oldValues['low'];
            }

            values['open'] = oldValues['open'];
          }

          chartValuesTmp[date] = values;
        }
      });

      // Second pass: transform to an array readable by jqplot OHLC renderer.
      var chartValues = [];
      $.each(chartValuesTmp, function(key, value) {
        chartValues.push([key, value['open'], value['high'], value['low'], value['close']]);
      });

      return chartValues;
    }, self);

    // Function to load entries from server for a specific account and month.
    self.loadEntries = function(account, month) {
      $.post("api/entry.php", {action: "get_entries", account: account.id, year: month.year, month: month.month}, function(data) {
          // Clean up current entries.
          self.entries.removeAll();

          // Clean up selected entry.
          self.selectedItem(null);

          self.entries(ko.utils.arrayMap(data, ko.mapping.fromJS));
      });
    };

    self.loadAccounts = function() {
      $.post("api/entry.php", {action: "get_accounts"}).success(function (result) {
        self.accounts(result);

        if(self.account()) {
          $.each(self.accounts(), function(index, account) {
            if(self.account().id == account.id) {
              self.account(account);
            }
          });
        }

        if(!self.account()){
          self.account(result[0]);
        }

        self.loadMonths(self.account());
      });
    };

    self.loadMonths = function(account){
      $.post("api/entry.php", {action: "get_months", account: account.id}).success(function (result) {
        self.months(result);
        
        if(self.month()) {
          $.each(self.months(), function(index, month) {
            if(self.month().year == month.year && self.month().month == month.month) {
              self.month(month);
            }
          });
        }

        if(!self.month()) {
          self.month(result[result.length - 1]);
        }

        self.loadEntries(self.account(), self.month());
      });
    };

    self.templateToUse = function (item) {
      return self.selectedItem() === item ? 'editTmpl' : 'itemsTmpl';
    };

    self.edit = function(item) {
      if(self.savedItem) {
        self.cancel();
      }

      self.savedItem=ko.toJS(item);
      self.selectedItem(item);

      $("#value_date").datepicker().on('changeDate', function(ev){
        self.selectedItem().value_date(ev.date.format(ev.currentTarget.dataset.dateFormat));
      });

      $("#operation_date").datepicker().on('changeDate', function(ev){
        self.selectedItem().operation_date(ev.date.format(ev.currentTarget.dataset.dateFormat));
      });
    };

    self.cancel = function() {
      if(self.selectedItem() && self.savedItem) {
        self.selectedItem().id(self.savedItem.id); // id should not change, but just in case...
        self.selectedItem().operation_date(self.savedItem.operation_date);
        self.selectedItem().value_date(self.savedItem.value_date);
        self.selectedItem().label(self.savedItem.label);
        self.selectedItem().value(self.savedItem.value);
        self.selectedItem().account_id(self.savedItem.account_id); // account_id should not change, but just in case...
      }

      // This item was just added.
      if(self.selectedItem() && !self.selectedItem().id()) {
        self.entries.remove(self.selectedItem());
      }

      self.savedItem = null;
      self.selectedItem(null);
    };

    self.add = function() {
      var newEntry = new entry({
        account_id: self.account().id
      });

      self.entries.unshift(newEntry);

      self.edit(newEntry);
    };

    self.save = function() {
      var item = ko.toJS(self.selectedItem());

      $.post("api/entry.php", {action: "save_entry", entry:item}).success(function(data) {
        message("success", "Save", data.message);

        self.selectedItem(null);
        self.loadAccounts();
      }).error(function() {
        message("error", "Error.", "Unexpected error.");
      });
    };

    self.remove = function (item) {
      if (item.id()) {
        self.itemToRemove(item);
        $('#remove-confirm').modal();
      } else {
        self.entries.remove(item);
      }
    };

    self.confirmRemove = function() {
      var item = self.itemToRemove();

      $.post("api/entry.php", {action: "remove_entry", entry:item}).success(function (result) {
        self.loadAccounts();
      }).complete(function (result) {
        self.itemToRemove(null);
        $('#remove-confirm').modal('hide');
      });
    };

    self.selectMonth = function(month) {
      if(month) {
        self.month(month);
        self.loadEntries(self.account(), month);
      }
    };

    self.selectAccount = function(account) {
      if(account) {
        self.account(account);
        self.loadMonths(account);
      }
    };
};

drawChart = function(entries, element) {
  // clear previous chart
  $(element).html("");

  if(entries && entries.length > 0) {
    var chartValues = [[], []];

    chartValues[0] = entries;

    var today = new Date();
    today.setHours(0);
    today.setMinutes(0);

    var day = 24 * 60 * 60 * 1000;

    var firstDate = new Date(Date.parse(entries[0][0]).valueOf() - day).format('yyyy-mm-dd');
    var lastDate = new Date(Date.parse(entries[entries.length -1][0]).valueOf() + day).format('yyyy-mm-dd');

    // plot chart
    window.chart = $.jqplot(element.id, chartValues, {
        title: "&Eacute;volution du solde",
        axes:{
          xaxis:{
            autoscale: true,
            renderer:$.jqplot.DateAxisRenderer,
            min: firstDate,
            max: lastDate,
            tickOptions: {formatString: "%F"}
          },
          yaxis: {
            autoscale: true,
          }
        },
        highlighter: {
          show:true,
          yvalues: 4,
          formatString:'<table class="jqplot-highlighter"><tr><td>date:</td><td>%s</td></tr><tr><td>open:</td><td>%s</td></tr><tr><td>hi:</td><td>%s</td></tr><tr><td>low:</td><td>%s</td></tr><tr><td>close:</td><td>%s</td></tr></table>'
        },

        series: [{
          renderer:$.jqplot.OHLCRenderer,
          color: "blue",
          lineWidth: 3,
          rendererOptions:{}
        }],
        canvasOverlay: {
          show: true,
          objects: [{
            dashedHorizontalLine: {
              name: "zero",
              y: 0,
              lineWidth: 1,
              color: "red",
              shadow: false
            }},
            { dashedVerticalLine: {
              name: "today",
              x: today,
              lineWidth: 1,
              color: "gray",
              shadow: false
            }}]
        }
    });
  } else {
    window.chart = null;
  }
};

drawPieChart = function(entries, element) {
  // clear previous chart
  $(element).html("");

  if(entries && entries.length > 0) {
    var chartValues = [[]];

    chartValues[0] = entries;

    // plot chart
    window.pieChart = $.jqplot(element.id, chartValues, {
        title: "D&eacute;penses",
        seriesDefaults: {
          renderer: $.jqplot.PieRenderer,
          rendererOptions: {
            showDataLabels: true
          }
        },
        legend: {
          show: true,
          location: 'e'
        },
        highlighter: {
          show: true,
          formatString:'%s: %s', 
          tooltipLocation:'sw', 
          useAxesFormatters:false
        }
    });
  } else {
    window.pieChart = null;
  }
};

ko.bindingHandlers.chart = {
    init: function (element, valueAccessor, allBindingsAccessor, viewModel) {
      // empty - left as placeholder if needed later
    },

    update: function (element, valueAccessor, allBindingsAccessor, viewModel) {
      var unwrap = ko.utils.unwrapObservable;
      var dataSource = valueAccessor();

      //var entries = dataSource ? unwrap(dataSource) : null;
      var entries = dataSource ? unwrap(dataSource) : null;
      drawChart(entries, element);
    }
};

ko.bindingHandlers.pieChart = {
    init: function (element, valueAccessor, allBindingsAccessor, viewModel) {
      // empty - left as placeholder if needed later
    },

    update: function (element, valueAccessor, allBindingsAccessor, viewModel) {
      var unwrap = ko.utils.unwrapObservable;
      var dataSource = valueAccessor();

      //var entries = dataSource ? unwrap(dataSource) : null;
      var entries = dataSource ? unwrap(dataSource) : null;
      drawPieChart(entries, element);
    }
};

$(document).ajaxError(function(event, xhr, settings) {
  message("error", "Error.", xhr.statusText);
});

$(window).resize(function() {
  if(window.chart) {
    window.chart.replot({resetAxes: true});
  }

  if(window.pieChart) {
    window.pieChart.replot({resetAxes: true});
  }
});

var viewModel = new ListViewModel();
ko.applyBindings(viewModel);

$(viewModel.loadAccounts);