Prototype of charting lib. Very barebones atm.

lib/chart.rb

@@ -0,0 +1,70 @@
+module GoogleChart
+  class Column
+    # http://code.google.com/apis/chart/interactive/docs/gallery/columnchart.html
+    #
+    # pretty simple right now; a config object in the future might be necessary
+    # if we add multiple charts on one page or whatever. JFDI.
+    #
+
+    attr_reader :set
+    attr_reader :column_names
+
+    def initialize(column_names, set)
+      unless column_names.kind_of?(Array)
+        raise ArgumentError, "please provide an array of column names."
+      end
+
+      unless set.kind_of?(Array) and set.all? { |x| x.kind_of?(Array) }
+        raise ArgumentError, "please use an array of array."
+      end
+
+      unless variable_name
+        raise ArgumentError, "damnit. really?"
+      end
+
+      @set           = set
+      @column_names  = column_names
+    end
+
+    def preamble
+      return <<-EOF
+        google.load("visualization", "1", {packages:["corechart"]});
+      EOF
+    end
+
+    def prepare_data 
+      javascript <<-EOF
+        var data = new google.visualization.DataTable();
+      EOF
+
+      column_names.each do |column_name|
+        javascript += "data.addColumn('string', '#{column_name.gsub(/'/, "\\'")}');\n"
+      end
+
+      javascript += "data.addRows(#{set.size});\n"
+
+      set.each_with_index do |row, i|
+        row.each_with_index do |item, j|
+          javascript += "data.setValue(#{i}, #{j},"
+          case item
+          when Numeric
+            javascript += item + ");\n"
+          else
+            javascript += "'#{item}');\n"
+          end
+        end
+      end
+
+      return javascript
+    end
+
+    def draw_chart(title, haxis_title, chart_div='chart_div')
+      return <<-EOF
+        var chart = new google.visualization.ColumnChart(document.getElementById('#{chart_div}'));
+        chart.draw(data, {width: 400, height: 240, title: '#{title}',
+                          hAxis: {title: '#{haxis_title}', titleTextStyle: {color: 'red'}}
+                         });
+      EOF
+    end
+  end
+end