Flip tool <--> tool_slot relations

app/controllers/api/tools_controller.rb

@@ -25,8 +25,7 @@ private
 
     def update_params
       output = {tool: tool}
-      output[:name]      = params[:name]         if params[:name]
-      output[:tool_slot] = params[:tool_slot_id] if params[:tool_slot_id]
+      output[:name] = params[:name] if params[:name]
       output
     end
 
@@ -36,8 +35,6 @@ private
       else
         @create_params = { name: params[:name],
                           device: current_device }
-        tsid = params[:tool_slot_id]
-        @create_params[:tool_slot_id] = tsid if tsid
         @create_params
       end
     end

app/models/tool.rb

@@ -1,6 +1,6 @@
 class Tool < ApplicationRecord
-  belongs_to :tool_slot
   belongs_to :device
+  has_one    :tool_slot
   validates  :device, presence: true
-  validates :name, uniqueness: { scope: :device }
+  validates  :name, uniqueness: { scope: :device }
 end

app/models/tool_slot.rb

@@ -1,4 +1,4 @@
 class ToolSlot < ApplicationRecord
-  has_many :tools
+  belongs_to :tool
   belongs_to :tool_bay
 end

app/mutations/tool_slots/base.rb

@@ -0,0 +1,30 @@
+module ToolSlots
+  class Base < Mutations::Command
+    def has_tool_id
+      !!tool_id
+    end
+    
+    def has_tool_bay
+        # Verifies that the tool bay EXISTS and is owned by user.
+      device.tool_bays.where(id: tool_bay_id).any?
+    end
+
+    def owns_tool
+      devices.tools.where(id: tool_id).any?
+    end
+
+    def validate_bay
+      add_error :tool_bay_id,
+                :not_found,
+                "Can't find tool bay with id #{tool_bay_id}" unless has_tool_bay
+    end
+
+    def validate_tool
+      if has_tool_id && !owns_tool
+        add_error :tool_id,
+                  :not_found,
+                  "Can't find tool with id #{tool_id}"
+      end
+    end
+  end
+end

app/mutations/tool_slots/create.rb

@@ -1,5 +1,5 @@
 module ToolSlots
-  class Create < Mutations::Command
+  class Create < ToolSlots::Base
     required do
       model :device, class: Device
       integer :tool_bay_id
@@ -14,11 +14,8 @@ module ToolSlots
     end
 
     def validate
-      if !device.tool_bays.where(id: tool_bay_id).any?
-        add_error :tool_bay_id,
-                  :not_found,
-                  "Can't find tool bay with id #{tool_bay_id}"
-      end
+      validate_tool
+      validate_bay
     end
 
     def execute

app/mutations/tool_slots/update.rb

@@ -1,11 +1,12 @@
 module ToolSlots
-  class Update < Mutations::Command
+  class Update < ToolSlots::Base
     required do
       model :device, class: Device
       model :tool_slot, class: ToolSlot
     end
 
     optional do
+      integer :tool_id
       string  :name
       integer :x
       integer :y

app/mutations/tools/base.rb

@@ -1,19 +0,0 @@
-module Tools
-  class Base < Mutations::Command
-    def it_is_your_tool_slot
-      (tool_slot.tool_bay.device_id == device.id)
-    end
-
-    def tool_slot
-      @tool_slot ||= ToolSlot.find_by(id: tool_slot_id)
-    end
-
-    def forbidden!
-      raise Errors::Forbidden
-    end
-
-    def bad_tool_slot_id!
-      add_error :tool_slot, :bad, "Bad tool slot ID"
-    end
-  end
-end

app/mutations/tools/create.rb

@@ -1,19 +1,10 @@
 module Tools
-  class Create  < Tools::Base
+  class Create < Mutations::Command
     required do
       string :name
       model :device, class: Device
     end
 
-    optional do
-      integer :tool_slot_id 
-    end
-
-    def validate
-      bad_tool_slot_id! if tool_slot_id && !tool_slot
-      forbidden! if tool_slot_id && !it_is_your_tool_slot
-    end
-
     def execute
       Tool.create!(inputs)
     end

app/mutations/tools/update.rb

@@ -1,17 +1,11 @@
 module Tools
-  class Update  < Tools::Base
+  class Update < Mutations::Command
     required do
       model :tool, class: Tool
     end
 
     optional do
       string :name
-      integer :tool_slot_id
-    end
-
-    def validate
-      bad_tool_slot_id! if tool_slot_id && !tool_slot
-      forbidden! if tool_slot_id && !it_is_your_tool_slot
     end
 
     def execute

app/serializers/tool_serializer.rb

@@ -1,3 +1,3 @@
 class ToolSerializer < ActiveModel::Serializer
-  attributes :id, :tool_slot_id, :name
+  attributes :id, :name
 end

app/serializers/tool_slot_serializer.rb

@@ -1,3 +1,3 @@
 class ToolSlotSerializer < ActiveModel::Serializer
-  attributes :id, :tool_bay_id, :name, :x, :y, :z
+  attributes :id, :tool_bay_id, :tool_id, :name, :x, :y, :z
 end

db/migrate/20161206210809_flip_flop_tools_relation.rb

@@ -0,0 +1,7 @@
+class FlipFlopToolsRelation < ActiveRecord::Migration[5.0]
+  def change
+    remove_column :tools,      :tool_slot_id, :integer
+    add_column    :tool_slots, :tool_id,      :integer
+    add_index     :tool_slots, :tool_id
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20161206162700) do
+ActiveRecord::Schema.define(version: 20161206210809) do
 
   create_table "delayed_jobs", force: :cascade do |t|
     t.integer  "priority",   default: 0, null: false
@@ -136,17 +136,17 @@ ActiveRecord::Schema.define(version: 20161206162700) do
     t.integer  "z"
     t.datetime "created_at",  null: false
     t.datetime "updated_at",  null: false
+    t.integer  "tool_id"
     t.index ["tool_bay_id"], name: "index_tool_slots_on_tool_bay_id"
+    t.index ["tool_id"], name: "index_tool_slots_on_tool_id"
   end
 
   create_table "tools", force: :cascade do |t|
-    t.integer  "tool_slot_id"
     t.string   "name"
-    t.datetime "created_at",   null: false
-    t.datetime "updated_at",   null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
     t.integer  "device_id"
     t.index ["device_id"], name: "index_tools_on_device_id"
-    t.index ["tool_slot_id"], name: "index_tools_on_tool_slot_id"
   end
 
   create_table "users", force: :cascade do |t|