Roll Observatory packages and add a roll script

charted/lib/charts/layout_renderers/pie_chart_renderer.dart

-//
-// Copyright 2014 Google Inc. All rights reserved.
-//
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file or at
-// https://developers.google.com/open-source/licenses/bsd
-//
-
-part of charted.charts;
-
-class PieChartRenderer extends LayoutRendererBase {
-  static const STATS_PERCENTAGE = 'percentage-only';
-  static const STATS_VALUE = 'value-only';
-  static const STATS_VALUE_PERCENTAGE = 'value-percentage';
-
-  final Iterable<int> dimensionsUsingBand = const[];
-  final String statsMode;
-  final num innerRadiusRatio;
-  final int maxSliceCount;
-  final String otherItemsLabel;
-  final String otherItemsColor;
-  final showLabels;
-  final sortDataByValue;
-
-  @override
-  final String name = "pie-rdr";
-
-  final List<ChartLegendItem> _legend = [];
-
-  Iterable otherRow;
-
-  PieChartRenderer({
-      num innerRadiusRatio: 0,
-      bool showLabels,
-      this.sortDataByValue: true,
-      this.statsMode: STATS_PERCENTAGE,
-      this.maxSliceCount: SMALL_INT_MAX,
-      this.otherItemsLabel: 'Other',
-      this.otherItemsColor: '#EEEEEE'})
-      : showLabels = showLabels == null ? innerRadiusRatio == 0 : showLabels,
-        innerRadiusRatio = innerRadiusRatio;
-
-  /// Returns false if the number of dimension axes != 0. Pie chart can only
-  /// be rendered on areas with no axes.
-  @override
-  bool prepare(ChartArea area, ChartSeries series) {
-    _ensureAreaAndSeries(area, series);
-    return area is LayoutArea;
-  }
-
-  @override
-  Iterable<ChartLegendItem> layout(
-      Element element, {Future schedulePostRender}) {
-    _ensureReadyToDraw(element);
-
-    var radius = math.min(rect.width, rect.height) / 2;
-    root.attr('transform', 'translate(${rect.width / 2}, ${rect.height / 2})');
-
-    // Pick only items that are valid - non-null and don't have null value
-    var measure = series.measures.first,
-        dimension = area.config.dimensions.first,
-        indices = new List.generate(area.data.rows.length, (i) => i);
-
-    // Sort row indices by value.
-    if (sortDataByValue) {
-      indices.sort((int a, int b) {
-        var aRow = area.data.rows.elementAt(a),
-            bRow = area.data.rows.elementAt(b),
-            aVal = (aRow == null || aRow.elementAt(measure) == null)
-                ? 0
-                : aRow.elementAt(measure),
-            bVal = (bRow == null || bRow.elementAt(measure) == null)
-                ? 0
-                : bRow.elementAt(measure);
-        return bVal.compareTo(aVal);
-      });
-    }
-
-    // Limit items to the passed maxSliceCount
-    if (indices.length > maxSliceCount) {
-      var displayed = indices.take(maxSliceCount).toList();
-      var otherItemsValue = 0;
-      for (int i = displayed.length; i < indices.length; ++i) {
-        var index = indices.elementAt(i),
-            row = area.data.rows.elementAt(index);
-        otherItemsValue += row == null || row.elementAt(measure) == null
-            ? 0
-            : row.elementAt(measure);
-      }
-      otherRow = new List(max([dimension, measure]) + 1)
-        ..[dimension] = otherItemsLabel
-        ..[measure] = otherItemsValue;
-      indices = displayed..add(SMALL_INT_MAX);
-    } else {
-      otherRow = null;
-    }
-
-    if (area.config.isRTL) {
-      indices = indices.reversed.toList();
-    }
-
-    var accessor = (d, i) {
-      var row = d == SMALL_INT_MAX ? otherRow : area.data.rows.elementAt(d);
-      return row == null || row.elementAt(measure) == null
-          ? 0
-          : row.elementAt(measure);
-    };
-    var data = (new PieLayout()..accessor = accessor).layout(indices),
-        arc = new SvgArc(
-            innerRadiusCallback: (d, i, e) => innerRadiusRatio * radius,
-            outerRadiusCallback: (d, i, e) => radius),
-        pie = root.selectAll('.pie-path').data(data);
-
-    pie.enter.append('path').classed('pie-path');
-    pie
-      ..each((d, i, e) {
-        var styles = stylesForData(d.data, i);
-        e.classes.removeAll(ChartState.VALUE_CLASS_NAMES);
-        if (!isNullOrEmpty(styles)) {
-          e.classes.addAll(styles);
-        }
-        e.attributes
-          ..['fill'] = colorForData(d.data, i)
-          ..['d'] = arc.path(d, i, host)
-          ..['stroke-width'] = '1px'
-          ..['stroke'] = '#ffffff';
-
-        e.append(
-            Namespace.createChildElement('text', e)
-              ..classes.add('pie-label'));
-      })
-      ..on('click', (d, i, e) => _event(mouseClickController, d, i, e))
-      ..on('mouseover', (d, i, e) => _event(mouseOverController, d, i, e))
-      ..on('mouseout', (d, i, e) => _event(mouseOutController, d, i, e));
-
-    pie.exit.remove();
-
-    _legend.clear();
-    var items = new List.generate(data.length, (i) {
-      SvgArcData d = data.elementAt(i);
-      Iterable row = d.data == SMALL_INT_MAX
-          ? otherRow
-          : area.data.rows.elementAt(d.data);
-
-      return new ChartLegendItem(index: d.data, color: colorForData(d.data, i),
-          label: row.elementAt(dimension), series: [series],
-          value: '${(((d.endAngle - d.startAngle) * 50) / math.PI).toStringAsFixed(2)}%');
-    });
-    return _legend..addAll(area.config.isRTL ? items.reversed : items);
-  }
-
-  String colorForData(int row, int index) =>
-      colorForValue(row, isTail: row == SMALL_INT_MAX);
-
-  Iterable<String> stylesForData(int row, int i) =>
-      stylesForValue(row, isTail: row == SMALL_INT_MAX);
-
-  @override
-  handleStateChanges(List<ChangeRecord> changes) {
-    root.selectAll('.pie-path').each((d, i, e) {
-      var styles = stylesForData(d.data, i);
-      e.classes.removeAll(ChartState.VALUE_CLASS_NAMES);
-      if (!isNullOrEmpty(styles)) {
-        e.classes.addAll(styles);
-      }
-      e.attributes['fill'] = colorForData(d.data, i);
-    });
-  }
-
-  @override
-  void dispose() {
-    if (root == null) return;
-    root.selectAll('.pie-path').remove();
-  }
-
-  void _event(StreamController controller, data, int index, Element e) {
-    // Currently, events are not supported on "Other" pie
-    if (controller == null || data.data == SMALL_INT_MAX) return;
-    controller.add(new DefaultChartEventImpl(
-         scope.event, area, series, data.data, series.measures.first, data.value));
-  }
-}