NEW: form-based many-to-many plans-tasks (#39)

lib/planner/tasks.ex

@@ -17,6 +17,7 @@ defmodule Planner.Tasks do
       order_by: [desc: t.updated_at]
     )
     |> Repo.all()
+    |> Repo.preload(:plans)
   end
 
   def list_unfinished_tasks_by_plan_id(plan_id) do
@@ -40,6 +41,7 @@ defmodule Planner.Tasks do
       order_by: [desc: t.updated_at]
     )
     |> Repo.all()
+    |> Repo.preload(:plans)
   end
 
   def get_task!(id), do: Repo.get!(Task, id)
@@ -60,9 +62,33 @@ defmodule Planner.Tasks do
   end
 
   def update_task(%Task{} = task, attrs) do
-    task
-    |> Task.changeset(attrs)
-    |> Repo.update()
+    new_plan_details_changesets = Enum.map(attrs["plans"], fn(plan_id) ->
+      PlanDetail.changeset(%PlanDetail{}, %{"task_id" => task.id, "plan_id" => plan_id})
+    end)
+
+    deleted_plan_details =
+      Ecto.Query.from(
+        pd in PlanDetail,
+        where: pd.task_id == ^task.id and pd.plan_id not in ^attrs["plans"]
+      )
+
+    multi =
+      Enum.reduce(
+       new_plan_details_changesets,
+        Multi.new()
+        |> Multi.update(:task, Task.changeset(task, attrs))
+        |> Multi.delete_all(:deleted_plan_details, deleted_plan_details),
+        fn(changeset, new_multi) ->
+          Multi.insert(
+            new_multi,
+            changeset.params["plan_id"],
+            changeset,
+            on_conflict: :nothing
+          )
+        end
+      )
+
+    Repo.transaction(multi)
   end
 
   def delete_task_by_id!(id) do

lib/planner_web/live/tasks_components.ex

@@ -50,6 +50,7 @@ defmodule TasksComponent do
             TaskComponent,
             id: "task:#{task.id}",
             task: task,
+            plans: @plans,
             live_action: @live_action,
             is_active: @active_task == task.id,
             route_show_task: @route_show_task,
@@ -96,7 +97,8 @@ defmodule TaskComponent do
                  <%= live_component(@socket,
                   TaskEditComponent,
                   id: "task_edit:#{@task.id}",
-                  task: @task
+                  task: @task,
+                  plans: @plans
                 )%>
               <% end %>
           <% else %>
@@ -225,9 +227,24 @@ defmodule TaskEditComponent do
           <%= error_tag(f, :due_at) %>
         </div>
 
+        <div class="field">
+          <label class="label">plans</label>
+          <div class="control">
+            <div class="select is-multiple is-dark">
+            <%= multiple_select(f,
+              :plans,
+              Enum.map(@plans, &({&1.name, &1.id})),
+              selected: Enum.map(@task.plans, &(&1.id))
+            ) %>
+            </div>
+          </div>
+        </div>
+
+        <div class="field">
           <div class="control">
             <%= submit("save", class: "button is-dark is-small") %>
           </div>
+        </div>
       </form>
     </div>
     """

lib/planner_web/live/tasks_live.ex

@@ -128,6 +128,7 @@ defmodule PlannerWeb.TasksLive do
             id: :tasks,
             live_action: @live_action,
             tasks: @tasks,
+            plans: @plans,
             active_plan: @active_plan,
             active_task: @active_task,
             route_show_task: @route_show_task,
@@ -168,11 +169,11 @@ defmodule PlannerWeb.TasksLive do
     task = Tasks.get_task!(task_params["id"])
 
     case Tasks.update_task(task, task_params) do
-      {:ok, task} ->
+      {:ok, changes} ->
         # I suspect splicing in the updated task isn't much faster than just refreshing the whole list
         socket =
           socket
-          |> refresh_tasks_and_flash_msg("task \"#{task.value}\" updated")
+          |> refresh_tasks_and_flash_msg("task \"#{changes.task.value}\" updated")
 
         route = get_index_route(socket)