From be16111c3438134c9c18ece2d793c89456cf378b Mon Sep 17 00:00:00 2001
From: Nolan J Tait <nolanjtait@gmail.com>
Date: Tue, 2 Apr 2024 12:12:55 -0700
Subject: [PATCH 1/4] Adds multiple and include blank options to select

---
 lib/superform/rails.rb | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/lib/superform/rails.rb b/lib/superform/rails.rb
index b93ede9..d26b7e0 100644
--- a/lib/superform/rails.rb
+++ b/lib/superform/rails.rb
@@ -299,16 +299,30 @@ def template(&content)
       end
 
       class SelectField < FieldComponent
-        def initialize(*, collection: [], **, &)
+        def initialize(
+          *,
+          collection: [],
+          multiple: false,
+          include_blank: false,
+          **,
+          &
+        )
           super(*, **, &)
           @collection = collection
+          @multiple = multiple
+          @include_blank = include_blank
         end
 
         def template(&options)
+          input(type: "hidden", name: dom.name, value: "") if @multiple
+
           if block_given?
             select(**attributes, &options)
           else
-            select(**attributes) { options(*@collection) }
+            select(**attributes) do
+              blank_option if @include_blank
+              options(*@collection)
+            end
           end
         end
 

From e8c97e273ea83c33ff01cef19334193c2fb92120 Mon Sep 17 00:00:00 2001
From: Nolan J Tait <nolanjtait@gmail.com>
Date: Tue, 2 Apr 2024 12:13:38 -0700
Subject: [PATCH 2/4] Adds overriding select name if multiple

---
 lib/superform/rails.rb | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/superform/rails.rb b/lib/superform/rails.rb
index d26b7e0..468b194 100644
--- a/lib/superform/rails.rb
+++ b/lib/superform/rails.rb
@@ -345,6 +345,13 @@ def false_option(&)
         end
 
         protected
+
+          def field_attributes
+            super.merge(
+              name: @multiple ? "#{dom.name}[]" : dom.name,
+            )
+          end
+
           def map_options(collection)
             OptionMapper.new(collection)
           end

From 155824e69a6fc6b67d8f4722ac361bbcaa9a0672 Mon Sep 17 00:00:00 2001
From: Nolan J Tait <nolanjtait@gmail.com>
Date: Tue, 2 Apr 2024 12:16:19 -0700
Subject: [PATCH 3/4] Adds multiple to select html attributes

---
 lib/superform/rails.rb | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/superform/rails.rb b/lib/superform/rails.rb
index 468b194..03d118f 100644
--- a/lib/superform/rails.rb
+++ b/lib/superform/rails.rb
@@ -349,6 +349,7 @@ def false_option(&)
           def field_attributes
             super.merge(
               name: @multiple ? "#{dom.name}[]" : dom.name,
+              multiple: @multiple
             )
           end
 

From 8a04f5ae1df08198331ff9b076232cbe071a8fbb Mon Sep 17 00:00:00 2001
From: Nolan J Tait <nolanjtait@gmail.com>
Date: Sun, 28 Apr 2024 02:06:21 -0700
Subject: [PATCH 4/4] Moves multiselect field to its own component

---
 lib/superform/rails.rb | 49 +++++++++++++++++++++++-------------------
 1 file changed, 27 insertions(+), 22 deletions(-)

diff --git a/lib/superform/rails.rb b/lib/superform/rails.rb
index 03d118f..844fc5c 100644
--- a/lib/superform/rails.rb
+++ b/lib/superform/rails.rb
@@ -69,6 +69,10 @@ def select(*collection, **attributes, &)
           Components::SelectField.new(self, attributes: attributes, collection: collection, &)
         end
 
+        def multiple_select(*collection, **attributes, &)
+          Components::MultipleSelectField.new(self, attributes: attributes, collection: collection, &)
+        end
+
         def title
           key.to_s.titleize
         end
@@ -299,30 +303,16 @@ def template(&content)
       end
 
       class SelectField < FieldComponent
-        def initialize(
-          *,
-          collection: [],
-          multiple: false,
-          include_blank: false,
-          **,
-          &
-        )
+        def initialize(*, collection: [], **, &)
           super(*, **, &)
           @collection = collection
-          @multiple = multiple
-          @include_blank = include_blank
         end
 
         def template(&options)
-          input(type: "hidden", name: dom.name, value: "") if @multiple
-
           if block_given?
             select(**attributes, &options)
           else
-            select(**attributes) do
-              blank_option if @include_blank
-              options(*@collection)
-            end
+            select(**attributes) { options(*@collection) }
           end
         end
 
@@ -344,18 +334,33 @@ def false_option(&)
           option(selected: field.value == false, value: false.to_s, &)
         end
 
+        protected
+
+          def map_options(collection)
+            OptionMapper.new(collection)
+          end
+      end
+
+      class MultipleSelectField < SelectField
+        def template(...)
+          # The HTML specification says when multiple parameter passed to select
+          # and all options got deselected web browsers do not send any value to
+          # server. Unfortunately this introduces a gotcha: if a User model has
+          # many roles and have role_ids accessor, and in the form that edits
+          # roles of the user the user deselects all roles from role_ids
+          # multiple select box, no role_ids parameter is sent.
+          input(type: "hidden", name: dom.name, value: "")
+          super(...)
+        end
+
         protected
 
           def field_attributes
             super.merge(
-              name: @multiple ? "#{dom.name}[]" : dom.name,
-              multiple: @multiple
+              name: "#{dom.name}[]",
+              multiple: true
             )
           end
-
-          def map_options(collection)
-            OptionMapper.new(collection)
-          end
       end
     end
   end