Redistat::KeySelection class and specs

lib/redistat.rb

@@ -12,6 +12,7 @@ require 'redistat/database'
 require 'redistat/date'
 require 'redistat/event'
 require 'redistat/key'
+require 'redistat/key_selection'
 require 'redistat/label'
 require 'redistat/model'
 require 'redistat/scope'

lib/redistat/key_selection.rb

@@ -0,0 +1,93 @@
+module Redistat
+  class KeySelection
+    
+    attr_reader :sets
+    
+    def initialize(start_date, end_date, depth = nil, interval = false)
+      @sets = self.class.find_date_sets(start_date, end_date, depth, interval)
+    end
+    
+    def self.find_date_sets(start_date, end_date, depth = nil, interval = false)
+      start_date = start_date.to_time if start_date.is_a?(::Date)
+      end_date = end_date.to_time if end_date.is_a?(::Date)
+      if !interval
+        find_date_sets_by_magic(start_date, end_date, depth)
+      else
+        find_date_sets_by_interval(start_date, end_date, depth)
+      end
+    end
+    
+    private
+    
+    def self.find_date_sets_by_magic(start_date, end_date, depth = nil)
+      depth ||= :hour
+      depths = Date::DEPTHS[Date::DEPTHS.index(:year), Date::DEPTHS.index(depth)+1].reverse
+      sets = []
+      depths.each_with_index do |d, i|
+        sets << find_start_keys_for(d, start_date, end_date, (i == 0))
+        sets << find_end_keys_for(d, start_date, end_date, (i == 0))
+      end
+      sets
+    end
+    
+    def self.find_date_sets_by_interval(start_date, end_date, depth)
+      depth ||= :hour
+      [{ :add => start_date.map_beginning_of_each(depth, :include_start => true, :include_end => true).until(end_date) { |t| t.to_rs.to_s(depth) },
+        :sub => [] }]
+      
+    end
+    
+    def self.find_start_keys_for(unit, start_date, end_date, lowest_depth = false)
+      return find_start_year_for(start_date, end_date, lowest_depth) if unit == :year
+      index = Date::DEPTHS.index(unit)
+      nunit = Date::DEPTHS[(index > 0) ? index-1 : index]
+      if start_date < start_date.round(nunit) || start_date.next(nunit).beginning_of(nunit) > end_date.beginning_of(nunit)
+        add = []
+        start_date.beginning_of_each(unit, :include_start => lowest_depth).until(start_date.end_of(nunit)) do |t|
+          add << t.to_rs.to_s(unit) if t < end_date.beginning_of(unit)
+        end
+        { :add => add, :sub => [] }
+      else
+        { :add => [start_date.beginning_of(nunit).to_rs.to_s(nunit)],
+          :sub => start_date.beginning_of(nunit).map_beginning_of_each(unit, :include_start => true, :include_end => !lowest_depth).until(start_date) { |t| t.to_rs.to_s(unit) } }
+      end
+    end
+    
+    def self.find_end_keys_for(unit, start_date, end_date, lowest_depth = false)
+      return find_end_year_for(start_date, end_date, lowest_depth) if unit == :year
+      index = Date::DEPTHS.index(unit)
+      nunit = Date::DEPTHS[(index > 0) ? index-1 : index]
+      has_nunit = end_date.prev(nunit).beginning_of(nunit) >= start_date.beginning_of(nunit)
+      nearest_nunit = end_date.round(nunit)
+      if end_date >= nearest_nunit
+        add = []
+        end_date.beginning_of(nunit).beginning_of_each(unit, :include_start => true, :include_end => lowest_depth).until(end_date) do |t|
+          add << t.to_rs.to_s(unit) if t > start_date.beginning_of(unit)
+        end
+        { :add => add, :sub => [] }
+      elsif has_nunit
+        { :add => [end_date.beginning_of(nunit).to_rs.to_s(nunit)], 
+          :sub => end_date.map_beginning_of_each(unit, :include_start => !lowest_depth).until(end_date.end_of(nunit)) { |t| t.to_rs.to_s(unit) } }
+      else
+        { :add => [], :sub => [] }
+      end
+    end
+    
+    def self.find_start_year_for(start_date, end_date, lowest_depth = false)
+      if start_date.years_since(1).beginning_of_year < end_date.beginning_of_year
+        { :add => start_date.map_beginning_of_each_year(:include_end => lowest_depth).until(end_date) { |t| t.to_rs.to_s(:year) }, :sub => [] }
+      else
+        { :add => [], :sub => [] }
+      end
+    end
+    
+    def self.find_end_year_for(start_date, end_date, lowest_depth = false)
+      if lowest_depth
+        { :add => [end_date.beginning_of_year.to_rs.to_s(:year)], :sub => [] }
+      else
+        { :add => [], :sub => [] }
+      end
+    end
+    
+  end
+end