Add minimum teaching days.

priv/repo/migrations/20170616131353_add_minimum_teaching_days.exs

@@ -0,0 +1,9 @@
+defmodule CoursePlanner.Repo.Migrations.AddMinimumTeachingDays do
+  use Ecto.Migration
+
+  def change do
+    alter table(:terms) do
+      add :minimum_teaching_days, :integer, null: false
+    end
+  end
+end

test/controllers/offered_course_controller_test.exs

@@ -23,6 +23,7 @@ defmodule CoursePlanner.OfferedCourseControllerTest do
         name: "Name",
         start_date: "2017-01-01",
         end_date: "2017-01-31",
+        minimum_teaching_days: 5,
         status: "Active"
       })
     term

test/controllers/term_controller_test.exs

@@ -42,6 +42,7 @@ defmodule CoursePlanner.TermControllerTest do
         name: "Spring",
         start_date: %{day: 01, month: 01, year: 2010},
         end_date: %{day: 01, month: 06, year: 2010},
+        minimum_teaching_days: 5,
         holidays:
         %{
           "0" => %{name: "Labor Day 1", date: %{day: 01, month: 05, year: 2010}},
@@ -84,6 +85,7 @@ defmodule CoursePlanner.TermControllerTest do
         name: "Spring",
         start_date: %{day: 01, month: 01, year: 2010},
         end_date: %{day: 01, month: 06, year: 2010},
+        minimum_teaching_days: 5,
         holidays:
         %{
           "0" => %{name: "Labor Day 1", date: %{day: 01, month: 5, year: 2008}}
@@ -99,6 +101,7 @@ defmodule CoursePlanner.TermControllerTest do
         name: "Spring",
         start_date: %{day: 01, month: 01, year: 2010},
         end_date: %{day: 01, month: 06, year: 2010},
+        minimum_teaching_days: 5,
         holidays:
         %{
           "0" => %{name: "Labor Day 1", date: %{day: 02, month: 01, year: 2011}}

test/lib/course_planner/offered_courses_test.exs

@@ -10,6 +10,7 @@ defmodule CoursePlanner.OfferedCoursesTest do
         name: "Fall",
         start_date: "2017-01-01",
         end_date: "2017-06-01",
+        minimum_teaching_days: 5,
         status: "Active"
       })
   end

test/lib/course_planner/teachers_test.exs

@@ -12,6 +12,7 @@ defmodule CoursePlanner.TeachersTest do
         name: name,
         start_date: start_date,
         end_date: end_date,
+        minimum_teaching_days: 5,
         courses: [course]
       })
   end

test/models/offered_course_test.exs

@@ -59,7 +59,8 @@ defmodule CoursePlanner.OfferedCourseTest do
       %Term{
         name: "Fall",
         start_date: %Ecto.Date{day: 1, month: 1, year: 2017},
-        end_date: %Ecto.Date{day: 1, month: 6, year: 2017}
+        end_date: %Ecto.Date{day: 1, month: 6, year: 2017},
+        minimum_teaching_days: 5
       })
   end
 

test/models/students_test.exs

@@ -12,6 +12,7 @@ defmodule CoursePlanner.StudentsTest do
          name: name,
          start_date: start_date,
          end_date: end_date,
+         minimum_teaching_days: 5,
          courses: [course]
        })
    end

test/models/term_test.exs

@@ -1,14 +1,15 @@
 defmodule CoursePlanner.TermTest do
   use CoursePlanner.ModelCase
 
-  alias CoursePlanner.Terms.Term
+  alias CoursePlanner.{Terms.Term, Terms}
 
   test "changeset with valid attributes" do
     valid_attrs =
       %{
         name: "Spring",
         start_date: %{day: 17, month: 4, year: 2010},
-        end_date: %{day: 17, month: 5, year: 2010}
+        end_date: %{day: 17, month: 5, year: 2010},
+        minimum_teaching_days: 5
       }
     changeset = Term.changeset(%Term{}, valid_attrs)
     assert changeset.valid?
@@ -36,9 +37,39 @@ defmodule CoursePlanner.TermTest do
       %{
         name: "Spring",
         start_date: %{day: 17, month: 4, year: 2010},
-        end_date: %{day: 17, month: 3, year: 2010}
+        end_date: %{day: 17, month: 3, year: 2010},
+        minimum_teaching_days: 5,
       }
     changeset = Term.changeset(%Term{}, invalid_attrs)
     refute changeset.valid?
   end
+
+  test "term has minimum teaching days" do
+    {:ok, term} = Terms.create(%{
+      "name" => "Spring",
+      "start_date" => %{day: 17, month: 3, year: 2017},
+      "end_date" => %{day: 22, month: 3, year: 2017},
+      "minimum_teaching_days" => 3,
+      "holidays" => %{
+        "0" => %{name: "Labor Day 1", date: %{day: 18, month: 3, year: 2017}},
+        "1" => %{name: "Labor Day 2", date: %{day: 19, month: 3, year: 2017}}
+      }
+    })
+    assert length(term.holidays) == 2
+  end
+
+  test "term doesn't have minimum teaching days" do
+    {:error, changeset} = Terms.create(%{
+      "name" => "Spring",
+      "start_date" => %{day: 17, month: 3, year: 2017},
+      "end_date" => %{day: 20, month: 3, year: 2017},
+      "minimum_teaching_days" => 3,
+      "holidays" => %{
+        "0" => %{name: "Labor Day 1", date: %{day: 18, month: 3, year: 2017}},
+        "1" => %{name: "Labor Day 2", date: %{day: 19, month: 3, year: 2017}}
+      }
+    })
+    refute changeset.valid?
+    assert changeset.errors[:minimum_teaching_days] == {"There's not enough minimum teaching days.", []}
+  end
 end

test/support/factory.ex

@@ -50,7 +50,8 @@ alias CoursePlanner.{User, Course, OfferedCourse, Class, Attendance}
    %Term{
      name: sequence(:name, &"term-#{&1}"),
      start_date: %Ecto.Date{day: 1, month: 1, year: 2017},
-     end_date: %Ecto.Date{day: 1, month: 6, year: 2017}
+     end_date: %Ecto.Date{day: 1, month: 6, year: 2017},
+     minimum_teaching_days: 5
    }
  end
 

web/models/terms.ex

@@ -57,7 +57,9 @@ defmodule CoursePlanner.Terms do
       |> Map.values()
       |> Enum.map(&Holiday.changeset(%Holiday{}, start_date, end_date, &1))
 
-    Changeset.put_embed(changeset, :holidays, holidays)
+    changeset
+    |> Changeset.put_embed(:holidays, holidays)
+    |> Term.validate_minimum_teaching_days(holidays)
   end
 
   def delete(id) do

web/models/terms/term.ex

@@ -11,6 +11,7 @@ defmodule CoursePlanner.Terms.Term do
     field :name, :string
     field :start_date, :date
     field :end_date, :date
+    field :minimum_teaching_days, :integer
     embeds_many :holidays, Holiday, on_replace: :delete
 
     has_many :offered_courses, OfferedCourse, on_replace: :delete
@@ -21,11 +22,24 @@ defmodule CoursePlanner.Terms.Term do
 
   def changeset(struct, params \\ %{}) do
     struct
-    |> cast(params, [:name, :start_date, :end_date])
-    |> validate_required([:name, :start_date, :end_date])
+    |> cast(params, [:name, :start_date, :end_date, :minimum_teaching_days])
+    |> validate_required([:name, :start_date, :end_date, :minimum_teaching_days])
     |> validate_date_range()
   end
 
+  def validate_minimum_teaching_days(%{valid?: true} = changeset, holidays) do
+    st = Changeset.get_field(changeset, :start_date)
+    en = Changeset.get_field(changeset, :end_date)
+    min = Changeset.get_field(changeset, :minimum_teaching_days)
+    number_of_holidays = length(holidays)
+    if Timex.diff(en, st, :days) + 1 - number_of_holidays > min do
+      changeset
+    else
+      Changeset.add_error(changeset, :minimum_teaching_days, "There's not enough minimum teaching days.")
+    end
+  end
+  def validate_minimum_teaching_days(changeset, _holidays), do: changeset
+
   defp validate_date_range(%{valid?: true} = changeset) do
     st = changeset |> Changeset.get_field(:start_date) |> Date.cast!
     en = changeset |> Changeset.get_field(:end_date) |> Date.cast!