Fix cancel button

src/lib/y2configuration_management/salt/form_controller.rb

@@ -57,10 +57,10 @@ class FormController
       # @param form [Y2ConfigurationManagement::Salt::Form]
       # @param pillar [Y2ConfigurationManagement::Salt::Pillar]
       def initialize(form, pillar)
-        @data = FormData.new(form, pillar)
         @form = form
         @pillar = pillar
-        @state = FormControllerState.new
+        data = FormData.from_pillar(form, pillar)
+        @state = FormControllerState.new(data)
       end
 
       # Renders the main form's dialog
@@ -83,7 +83,7 @@ def show_main_dialog
       #
       # @param locator [String] Locator of the element
       def get(locator)
-        @data.get(locator)
+        form_data.get(locator)
       end
 
       # Opens a new dialog in order to add a new element to a collection
@@ -105,7 +105,7 @@ def edit(relative_locator)
       # @param relative_locator [FormElementLocator] Elements's locator
       def remove(relative_locator)
         locator = state.locator.join(relative_locator)
-        @data.remove_item(locator)
+        form_data.remove_item(locator)
         refresh_top_form
       end
 
@@ -149,8 +149,8 @@ def show_popup(widget)
       #   version.
       def next_handler
         state.form_widget.store
-        data.update(form.root.locator, state.form_widget.result)
-        pillar.data = data.to_h.fetch("root", {})
+        form_data.update(form.root.locator, state.form_widget.result)
+        pillar.data = form_data.to_h.fetch("root", {})
         puts pillar.dump
         true
       end
@@ -167,7 +167,7 @@ def add_or_edit_item(action, relative_locator)
         add_or_update_parent
         result = run_popup(action, relative_locator)
         update_form_data(result)
-        state.close_form
+        state.close_form(rollback: result.nil?)
         refresh_top_form
       end
 
@@ -186,13 +186,16 @@ def run_popup(action, relative_locator)
 
       # Updates the form data depending on the action
       #
+      # When result is `nil`, it just restores the backup.
+      #
       # @param result [Hash,nil] Result to process
       def update_form_data(result)
-        return if result.nil?
+        return nil if result.nil?
+
         if state.action == :add
-          @data.add_item(state.locator, result)
+          form_data.add_item(state.locator, result)
         else
-          @data.update(state.locator, result)
+          form_data.update(state.locator, result)
         end
       end
 
@@ -205,9 +208,9 @@ def add_or_update_parent
         parent = state.form_widget.result
 
         if state.action == :edit
-          @data.update(state.locator, parent)
+          form_data.update(state.locator, parent)
         else
-          @data.add_item(state.locator, parent)
+          form_data.add_item(state.locator, parent)
           locator = state.locator.join(get(state.locator).size - 1)
           state.replace(:edit, locator)
         end
@@ -223,6 +226,13 @@ def item_form_for(locator)
         form_widget.title = element.name
         form_widget
       end
+
+      # Returns the current form data
+      #
+      # @return [FormData] Form data
+      def form_data
+        @state.form_data
+      end
     end
   end
 end

src/lib/y2configuration_management/salt/form_controller_state.rb

@@ -24,15 +24,18 @@ module Salt
     # Stores the UI state information
     #
     # This class holds information related to FormController. Basically, it behaves like a stack
-    # which contains informaion about the open widget forms.  This data could have been stored
-    # directly in the FormController instance, but it has been extracted in order to keep the
-    # controller as simple as possible.
+    # which contains informaion about the open widget forms and the current form data. Those items
+    # could have been stored directly in the FormController instance, but they have been extracted
+    # in order to keep the controller as simple as possible.
     class FormControllerState
       # Constructor
-      def initialize
+      #
+      # @param data [FormData] Initial form data
+      def initialize(data)
         @form_widgets = []
         @locators = []
         @actions = []
+        @form_data_snapshots = [data]
       end
 
       # Registers that a new form has been open
@@ -46,6 +49,7 @@ def open_form(action, locator, form_widget)
         @form_widgets << form_widget
         @locators << locator
         @actions << action
+        backup_data
       end
 
       # Most recently open form widget
@@ -70,16 +74,53 @@ def locator
       end
 
       # Replaces the current action/locator
+      #
+      # @param new_action  [Symbol]
+      # @param new_locator [FormElementLocator]
       def replace(new_action, new_locator)
         @actions[-1] = new_action
         @locators[-1] = new_locator
       end
 
       # Removes the information related to the most recently open form widget
-      def close_form
+      def close_form(rollback: false)
         @form_widgets.pop
         @locators.pop
         @actions.pop
+        if rollback
+          restore_backup
+        else
+          remove_backup
+        end
+      end
+
+      # Current form data
+      #
+      # @return [FormData]
+      def form_data
+        @form_data_snapshots.last
+      end
+
+    private
+
+      # Performs a backup of the current form data
+      def backup_data
+        @form_data_snapshots << form_data.copy
+      end
+
+      # Restores the last backup of the current form data by removing the current snapshot
+      def restore_backup
+        @form_data_snapshots.pop
+      end
+
+      # @return [Integer] Position of the previous backup
+      PREVIOUS_SNAPSHOT_POSITION = -2
+
+      # Clears the last backup if it exists
+      def remove_backup
+        # This is another way of saying `top = @fdi.pop; @fdi.last = top`,
+        # or "shorten the snapshot stack but commit the last element"
+        @form_data_snapshots.delete_at(PREVIOUS_SNAPSHOT_POSITION)
       end
     end
   end

src/lib/y2configuration_management/salt/form_data.rb

@@ -17,33 +17,36 @@
 # To contact SUSE LLC about this file by physical or electronic mail, you may
 # find current contact information at www.suse.com.
 
-require "y2configuration_management/salt/pillar"
+require "y2configuration_management/salt/form_data_reader"
 
 module Y2ConfigurationManagement
   module Salt
     # This class holds data for a given Salt Formula Form
-    #
-    # @todo The support for collections is rather simple and nesting collections is not supported.
-    #       We might consider using JSON Patch to modify the data.
     class FormData
       # @return [Y2ConfigurationManagement::Salt::Form] Form
       attr_reader :form
-      # @return [Y2ConfigurationManagement::Salt::Pillar] Pillar
-      attr_reader :pillar
+
+      class << self
+        # @param form   [Form] Form definition
+        # @param pillar [Pillar] Pillar to read the data from
+        # @return [FormData] Form data merging defaults and pillar values
+        def from_pillar(form, pillar)
+          FormDataReader.new(form, pillar).form_data
+        end
+      end
 
       # Constructor
       #
-      # @param form [Y2ConfigurationManagement::Salt::Form] Form
-      # @param pillar [Y2ConfigurationManagement::Salt::Form] Pillar
-      def initialize(form, pillar = Pillar.new(data: {}))
-        @data = data_for_form(form, pillar.data)
+      # @param form [Form] Form definition
+      # @param data [Hash] Initial data in hash form
+      def initialize(form, initial = {})
         @form = form
-        @pillar = pillar
+        @data = initial
       end
 
       # Returns the value of a given element
       #
-      # @param locator [String] Locator of the element
+      # @param locator [FormElementLocator] Locator of the element
       def get(locator)
         find_by_locator(@data, locator) || default_for(locator)
       end
@@ -88,13 +91,20 @@ def to_h
         data_for_pillar(@data)
       end
 
+      # Returns a copy of this object
+      #
+      # @return [FormData]
+      def copy
+        self.class.new(form, Marshal.load(Marshal.dump(@data)))
+      end
+
     private
 
       # Recursively finds a value
       #
       # @param data    [Hash,Array] Data structure to search for the value
       # @param locator [FormElementLocator] Value locator
-      # @return [Object] Value
+      # @return [Object,nil] Found value; nil if no value was found for the given locator
       def find_by_locator(data, locator)
         return nil if data.nil?
         return data if locator.first.nil?
@@ -116,62 +126,6 @@ def default_for(locator)
         element ? element.default : nil
       end
 
-      # Builds a hash to keep the form data
-      #
-      # @param form [Y2ConfigurationManagement::Salt::Form]
-      # @param data [Hash] Pillar data
-      # @return [Hash]
-      def data_for_form(form, data)
-        data_for_element(form.root, data)
-      end
-
-      # Builds a hash to keep the form element data
-      #
-      # @param element [Y2ConfigurationManagement::Salt::FormElement]
-      # @param data [Hash] Pillar data
-      # @return [Hash]
-      def data_for_element(element, data)
-        if element.is_a?(Container)
-          defaults = element.elements.reduce({}) { |a, e| a.merge(data_for_element(e, data)) }
-          { element.id => defaults }
-        else
-          value = find_in_pillar_data(data, element.locator.rest) # FIXME: remove '.root'
-          value ||= element.default
-          { element.id => data_from_pillar_collection(value, element) }
-        end
-      end
-
-      # Converts from a Pillar collection into form data
-      #
-      # Basically, a collection might be an array or a hash. The internal representation, however,
-      # is always an array, so it is needed to do the conversion.
-      #
-      # @param element [Y2ConfigurationManagement::Salt::FormElement]
-      # @param value   [Array,Hash]
-      # @return
-      def data_from_pillar_collection(collection, element)
-        return nil if collection.nil?
-        return collection unless element.respond_to?(:keyed?) && element.keyed?
-        collection.map do |k, v|
-          { "$key" => k }.merge(v)
-        end
-      end
-
-      # Finds a value within a Pillar
-      #
-      # @todo This API might be available through the Pillar class.
-      #
-      # @param data    [Hash,Array] Data structure from the Pillar
-      # @param locator [FormElementLocator] Value locator
-      # @return [Object] Value
-      def find_in_pillar_data(data, locator)
-        return nil if data.nil?
-        return data if locator.first.nil?
-        key = locator.first
-        key = key.is_a?(Symbol) ? key.to_s : key
-        find_in_pillar_data(data[key], locator.rest)
-      end
-
       # Returns data in a format to be used by the Pillar
       #
       # @param data [Object]