use start of week not month

app/controllers/timeline_controller.rb

@@ -4,7 +4,7 @@ class TimelineController < ApplicationController
     @weeks = (params[:weeks] || "12").to_i
     @members = Member.visible_scope.
                 where("leaving > ? " , Date.today).
-                where("arriving < ? " , Date.today.at_beginning_of_month + @weeks.weeks).
+                where("arriving < ? " , helpers.start_day + @weeks.weeks).
                 order(:arriving).
                 page(1).per(50)
   end

app/helpers/timeline_helper.rb

@@ -9,22 +9,25 @@ module TimelineHelper
   def max_days
     @weeks * 7
   end
+  def start_day
+    Date.today.at_beginning_of_week - 1.week
+  end
   # number of days from start of month to start of stay
   def started_days(member)
     return 0 unless member.arriving
-    return 0 if member.arriving < Date.today.at_beginning_of_month
-    distance = (member.arriving - Date.today.at_beginning_of_month).to_i
+    return 0 if member.arriving < start_day
+    distance = (member.arriving - start_day).to_i
     distance > max_days ? max_days : distance
   end
   def left_max
-    Date.today.at_beginning_of_month + 3.months
+    start_day + 3.months
   end
 
   # amount of days of the stay, maxed at the number fo weeks shown
   def stay_days(member)
     return 0 unless member.leaving
     start = member.arriving
-    start = Date.today.at_beginning_of_month if member.arriving < Date.today.at_beginning_of_month
+    start = start_day if member.arriving < start_day
     distance = ( member.leaving - start ).to_i
     max = max_days - started_days(member)
     distance > max ? max : distance
@@ -32,7 +35,7 @@ module TimelineHelper
 
   # weekly occupany, hash containing weeks to number of volunteer mapping
   def weekly
-    month_start = Date.today.at_beginning_of_month
+    month_start = start_day
     ( 0 ... @weeks ).collect do |week|
       amount = -1
       start_week = month_start + week.weeks

app/views/timeline/index.haml

@@ -10,7 +10,7 @@
     %tr
       - (0...@weeks).each do |week|
         %td{colspan: 7 , class: bg_for(week + 2)  }
-          = small_date(Date.today.at_beginning_of_month + week.weeks)
+          = small_date(start_day + week.weeks)
     %tr
       - weekly.each_with_index do |amount , week |
         %td{colspan: 7, class: bg_for(week + 2) , style: "width: #{week_pixels}px;"}= amount