Calendar features (sans vacances scolaires)

lib/analyzer/predictor/calendar/day_offs.ex

+defmodule Analyzer.Predictor.Calendar.DayOffs do
+@moduledoc """
+  Jour de fêtes
+"""
+
+  def all_saints(date) do
+    Date.new!(date.year, 11, 1)
+  end
+
+  def workers_day(date) do
+    Date.new!(date.year, 5, 1)
+  end
+
+  def christmas(date) do
+    Date.new!(date.year, 12, 25)
+  end
+
+  def easter(year) do
+    a = Integer.mod(year, 19)
+    b = Integer.floor_div(year, 100)
+    c = Integer.mod(year, 100)
+    d = Integer.floor_div(b, 4)
+    e = Integer.mod(b, 4)
+    tmp1 = 8 * b + 13
+    g = Integer.floor_div(tmp1, 25)
+
+    tmp2 = 19 * a + b - d - g + 15
+    h = Integer.mod(tmp2, 30)
+    j = Integer.floor_div(c, 4)
+    k = Integer.mod(c, 4)
+
+    tmp3 = a + 11 * h
+    m =  Integer.floor_div(tmp3, 319)
+
+    tmp4 = 2 * e + 2 * j - k - h + m + 32
+    r = Integer.mod(tmp4, 7)
+
+    tmp5 = h - m + r + 90
+    n = Integer.floor_div(tmp5, 25)
+
+    tmp6 = h - m + r + n + 19
+    p = Integer.mod(tmp6, 32)
+
+    Date.new!(year, n, p)
+  end
+
+  def easter_monday(easter) do
+    Date.add(easter, 1)
+  end
+
+  def ascension(easter) do
+    Date.add(easter, 39)
+  end
+
+  def pentecost(easter) do
+    Date.add(easter, 49)
+  end
+
+  def pentecost_monday(easter) do
+    Date.add(easter, 50)
+  end
+
+  def independance_day(date) do
+    Date.new!(date.year, 6, 26)
+  end
+
+end