Simplify theme helper

app/helpers/theme_helper.rb

@@ -28,15 +28,6 @@ module ThemeHelper
     "muted_text"         => "muted-text",
   }.freeze
 
-  def render_theme
-    theme = get_active_theme
-
-    return unless theme
-
-    css = get_theme_css(theme)
-    content_tag(:style, css)
-  end
-
   def get_theme_css(theme)
     body = ":root {\n"
 
@@ -61,7 +52,7 @@ module ThemeHelper
   end
 
   def theme_color
-    theme = get_active_theme
+    theme = active_theme_user&.theme
     if theme
       theme.theme_color
     else
@@ -70,7 +61,7 @@ module ThemeHelper
   end
 
   def mobile_theme_color
-    theme = get_active_theme
+    theme = active_theme_user&.theme
     if theme
       theme.mobile_theme_color
     else
@@ -78,32 +69,18 @@ module ThemeHelper
     end
   end
 
-  def get_active_theme
-    if @user&.theme
-      if user_signed_in?
-        if current_user&.show_foreign_themes?
-          @user.theme
-        else
-          current_user&.theme
-        end
-      else
-        @user.theme
-      end
-    elsif @answer&.user&.theme
-      if user_signed_in?
-        if current_user&.show_foreign_themes?
-          @answer.user.theme
-        else
-          current_user&.theme
-        end
-      else
-        @answer.user.theme
-      end
-    elsif current_user&.theme
-      current_user.theme
+  def active_theme_user
+    user = @user ||= @answer&.user
+
+    if user&.theme.present? && should_show_foreign_theme?
+      user
+    elsif user_signed_in?
+      current_user
     end
   end
 
+  def should_show_foreign_theme? = current_user&.show_foreign_themes || !user_signed_in?
+
   def get_hex_color_from_theme_value(value)
     "0000000#{value.to_s(16)}"[-6, 6]
   end

app/views/layouts/base.html.haml

@@ -5,10 +5,10 @@
     %meta{ 'http-equiv': 'X-UA-Compatible', content: 'IE=edge' }
     %meta{ name: 'viewport', content: 'width=device-width, initial-scale=1, user-scalable=no, viewport-fit=cover' }
     - if user_signed_in?
-      %meta{ name: 'theme-color', content: "var(--primary)", media: '(min-width: 993px)' }
-      %meta{ name: 'theme-color', content: "var(--background)", media: '(max-width: 992px)' }
+      %meta{ name: "theme-color", content: "var(--primary)", media: "(min-width: 993px)" }
+      %meta{ name: "theme-color", content: "var(--background)", media: "(max-width: 992px)" }
     - else
-      %meta{ name: 'theme-color', content: "var(--primary)" }
+      %meta{ name: "theme-color", content: "var(--primary)" }
     - if @user&.privacy_noindex? || @answer&.user&.privacy_noindex? || @question&.user&.privacy_noindex?
       %meta{ name: 'robots', content: 'noindex' }
     %link{ rel: 'manifest', href: '/manifest.json', crossorigin: 'use-credentials' }
@@ -19,10 +19,7 @@
     %link{ rel: 'icon', href: '/images/favicon/favicon-32.png', sizes: '32x32' }
     %title= yield(:title)
     = stylesheet_link_tag "application", data: { 'turbo-track': "reload" }, media: "all"
-    - if current_user&.show_foreign_themes?
-      %link{ rel: 'stylesheet', href: user_path(username: @user&.screen_name || @answer&.user&.screen_name || current_user&.screen_name, format: "css"), data: { turbo_track: "reload" } }
-    - elsif user_signed_in?
-      %link{ rel: 'stylesheet', href: user_path(username: current_user&.screen_name, format: "css"), data: { turbo_track: "reload" } }
+    %link{ rel: "stylesheet", href: user_path(username: active_theme_user.screen_name, format: "css"), data: { turbo_track: "reload" } }
     = javascript_include_tag 'application', data: { 'turbo-track': 'reload' }, defer: true
     = csrf_meta_tags
     = yield(:og)

spec/helpers/theme_helper_spec.rb

@@ -3,33 +3,6 @@
 require "rails_helper"
 
 describe ThemeHelper, type: :helper do
-  describe "#render_theme" do
-    context "when target page doesn't have a theme" do
-      it "returns no theme" do
-        expect(helper.render_theme).to be_nil
-      end
-    end
-
-    context "when target page has a theme" do
-      before(:each) do
-        @user = FactoryBot.create(:user)
-        @user.theme = Theme.new
-        @user.save!
-      end
-
-      it "returns a theme" do
-        expect(helper.render_theme).to include("<style>:root {")
-      end
-
-      it "contains correct theme background colors" do
-        expect(helper.render_theme).to include("--primary: #5e35b1;")
-      end
-
-      it "properly converts color values for *-text theme attributes" do
-        expect(helper.render_theme).to include("--primary-text: 255, 255, 255;")
-      end
-    end
-  end
 
   describe "#get_hex_color_from_theme_value" do
     it "returns the proper hex value from the decimal value for white" do
@@ -51,11 +24,11 @@ describe ThemeHelper, type: :helper do
     end
   end
 
-  describe "#get_active_theme" do
+  describe "#active_theme_user" do
     context "when user is a guest" do
       context "when target page doesn't have a theme" do
-        it "returns no theme" do
-          expect(helper.get_active_theme).to be_nil
+        it "returns no user" do
+          expect(helper.active_theme_user).to be_nil
         end
       end
 
@@ -67,7 +40,7 @@ describe ThemeHelper, type: :helper do
         end
 
         it "returns a theme" do
-          expect(helper.get_active_theme).to be_a(Theme)
+          expect(helper.active_theme_user).to be_a(User)
         end
       end
 
@@ -78,8 +51,8 @@ describe ThemeHelper, type: :helper do
           @answer.user.save!
         end
 
-        it "returns a theme" do
-          expect(helper.get_active_theme).to be_a(Theme)
+        it "returns a user" do
+          expect(helper.active_theme_user).to be_a(User)
         end
       end
     end
@@ -90,13 +63,7 @@ describe ThemeHelper, type: :helper do
       before(:each) { sign_in(user) }
 
       context "when user has no theme" do
-        context "when target page has no theme" do
-          it "returns no theme" do
-            expect(helper.get_active_theme).to be_nil
-          end
-        end
-
-        context "when target page has a theme" do
+        context "when target page has a corresponding user" do
           let(:theme) { Theme.new }
 
           before(:each) do
@@ -106,11 +73,11 @@ describe ThemeHelper, type: :helper do
           end
 
           it "returns a theme" do
-            expect(helper.get_active_theme).to be(theme)
+            expect(helper.active_theme_user).to be(@user)
           end
         end
 
-        context "when target answer's user has a theme" do
+        context "when target page has contains an answer" do
           let(:theme) { Theme.new }
 
           before(:each) do
@@ -120,7 +87,7 @@ describe ThemeHelper, type: :helper do
           end
 
           it "returns a theme" do
-            expect(helper.get_active_theme).to be(theme)
+            expect(helper.active_theme_user).to be(@answer.user)
           end
         end
       end
@@ -136,7 +103,7 @@ describe ThemeHelper, type: :helper do
 
         context "when target page has no theme" do
           it "returns the theme of the current user" do
-            expect(helper.get_active_theme).to eq(theme)
+            expect(helper.active_theme_user).to eq(user)
           end
         end
 
@@ -150,7 +117,7 @@ describe ThemeHelper, type: :helper do
           end
 
           it "returns the theme of the current page" do
-            expect(helper.get_active_theme).to eq(user_theme)
+            expect(helper.active_theme_user).to eq(@user)
           end
 
           context "when user doesn't allow foreign themes" do
@@ -160,7 +127,7 @@ describe ThemeHelper, type: :helper do
             end
 
             it "should return the users theme" do
-              expect(helper.get_active_theme).to eq(theme)
+              expect(helper.active_theme_user).to eq(user)
             end
           end
         end
@@ -175,7 +142,7 @@ describe ThemeHelper, type: :helper do
           end
 
           it "returns the theme of the current page" do
-            expect(helper.get_active_theme).to eq(answer_theme)
+            expect(helper.active_theme_user).to eq(@answer.user)
           end
 
           context "when user doesn't allow foreign themes" do
@@ -185,7 +152,7 @@ describe ThemeHelper, type: :helper do
             end
 
             it "should return the users theme" do
-              expect(helper.get_active_theme).to eq(theme)
+              expect(helper.active_theme_user).to eq(user)
             end
           end
         end