Add ability to style box frame and content

lib/tty/box.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require 'pastel'
 require 'tty-cursor'
 
 require_relative 'box/version'
@@ -61,66 +62,105 @@ def cursor
       TTY::Cursor
     end
 
-    def frame(top: 0, left: 0, title: {}, width: 35, height: 3, border: :light)
+    def color
+      @color ||= Pastel.new
+    end
+
+    # Create a frame
+    #
+    # @api public
+    def frame(top: 0, left: 0, width: 35, height: 3,
+              title: {}, border: :light, style: {})
       output = []
       content = []
       content = yield.split("\n") if block_given?
+      fg, bg = *extract_style(style)
+      border_fg, border_bg = *extract_style(style[:border] || {})
 
       output << cursor.move_to(left, top)
-      output << top_border(title, width, border)
+      output << top_border(title, width, border, style)
       (height - 2).times do |i|
         output << cursor.move_to(left, top + i + 1)
-        output << pipe_char(border)
-        output << content[i]
+        output << border_bg.(border_fg.(pipe_char(border)))
+        if content[i].nil?
+          output << bg.(fg.(' ' * (width - 2))) if style[:fg] || style[:bg]
+        else
+          output << bg.(fg.(content[i]))
+          if style[:fg] || style[:bg]
+            output << bg.(fg.(' ' * (width - 2 - content[i].size)))
+          end
+        end
         output << cursor.move_to(left + width - 1, top + i + 1)
-        output << pipe_char(border)
+        output << border_bg.(border_fg.(pipe_char(border)))
       end
       output << cursor.move_to(left, top + height - 1)
-      output << bottom_border(title, width, border)
+      output << bottom_border(title, width, border, style)
 
       output.join
     end
 
-    def top_border(title, width, border)
+    # Convert style keywords into styling
+    #
+    # @return [Array[Proc, Proc]]
+    #
+    # @api private
+    def extract_style(style)
+      fg = style[:fg] ? color.send(style[:fg]).detach : -> (c) { c }
+      bg = style[:bg] ? color.send(:"on_#{style[:bg]}").detach : -> (c) { c }
+      [fg, bg]
+    end
+
+    # Top border
+    #
+    # @return [String]
+    #
+    # @api private
+    def top_border(title, width, border, style)
       top_titles_size = title[:top_left].to_s.size +
                         title[:top_center].to_s.size +
                         title[:top_right].to_s.size
-
+      fg, bg = *extract_style(style[:border] || {})
 
       top_space_left = width - top_titles_size -
                        top_left_char.size - top_right_char.size
       top_space_before = top_space_left / 2
       top_space_after = top_space_left / 2 + top_space_left % 2
 
       [
-        top_left_char(border),
-        title[:top_left].to_s,
-        line_char(border) * top_space_before,
-        title[:top_center].to_s,
-        line_char(border) * top_space_after,
-        title[:top_right].to_s,
-        top_right_char(border)
+        bg.(fg.(top_left_char(border))),
+        bg.(title[:top_left].to_s),
+        bg.(fg.(line_char(border) * top_space_before)),
+        bg.(title[:top_center].to_s),
+        bg.(fg.(line_char(border) * top_space_after)),
+        bg.(title[:top_right].to_s),
+        bg.(fg.(top_right_char(border)))
       ].join('')
     end
 
-    def bottom_border(title, width, border)
+    # Bottom border
+    #
+    # @return [String]
+    #
+    # @api private
+    def bottom_border(title, width, border, style)
       bottom_titles_size = title[:bottom_left].to_s.size +
                            title[:bottom_center].to_s.size +
                            title[:bottom_right].to_s.size
+      fg, bg = *extract_style(style[:border] || {})
 
       bottom_space_left = width - bottom_titles_size -
                           bottom_left_char.size - bottom_right_char.size
       bottom_space_before = bottom_space_left / 2
       bottom_space_after = bottom_space_left / 2 + bottom_space_left % 2
 
       [
-        bottom_left_char(border),
-        title[:bottom_left].to_s,
-        line_char(border) * bottom_space_before,
-        title[:bottom_center].to_s,
-        line_char(border) * bottom_space_after,
-        title[:bottom_right].to_s,
-        bottom_right_char(border)
+        bg.(fg.(bottom_left_char(border))),
+        bg.(title[:bottom_left].to_s),
+        bg.(fg.(line_char(border) * bottom_space_before)),
+        bg.(title[:bottom_center].to_s),
+        bg.(fg.(line_char(border) * bottom_space_after)),
+        bg.(title[:bottom_right].to_s),
+        bg.(fg.(bottom_right_char(border)))
       ].join('')
     end
   end # TTY

spec/unit/style_spec.rb

@@ -0,0 +1,29 @@
+RSpec.describe TTY::Box, ":style option" do
+  it "applies styling to content and border" do
+    box = TTY::Box.frame(
+      width: 30,
+      height: 4,
+      border: :thick,
+      title: {
+        top_left: ' file1 '
+      },
+      style: {
+        fg: :bright_yellow,
+        bg: :blue,
+        border: {
+          fg: :bright_yellow,
+          bg: :blue
+        }
+      }
+    ) do
+      "Midnight Commander\n is the best"
+    end
+
+    expect(box).to eq([
+      "\e[1;1H\e[44m\e[93m╔\e[0m\e[0m\e[44m file1 \e[0m\e[44m\e[93m══════════\e[0m\e[0m\e[44m\e[93m═══════════\e[0m\e[0m\e[44m\e[93m╗\e[0m\e[0m",
+      "\e[2;1H\e[44m\e[93m║\e[0m\e[0m\e[44m\e[93mMidnight Commander\e[0m\e[0m\e[44m\e[93m          \e[0m\e[0m\e[2;30H\e[44m\e[93m║\e[0m\e[0m",
+      "\e[3;1H\e[44m\e[93m║\e[0m\e[0m\e[44m\e[93m is the best\e[0m\e[0m\e[44m\e[93m                \e[0m\e[0m\e[3;30H\e[44m\e[93m║\e[0m\e[0m",
+      "\e[4;1H\e[44m\e[93m╚\e[0m\e[0m\e[44m\e[93m══════════════\e[0m\e[0m\e[44m\e[93m══════════════\e[0m\e[0m\e[44m\e[93m╝\e[0m\e[0m"
+    ].join)
+  end
+end

tty-box.gemspec

@@ -20,6 +20,7 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
+  spec.add_dependency 'pastel', '~> 0.7.2'
   spec.add_dependency 'tty-cursor', '~> 0.5.0'
 
   spec.add_development_dependency "bundler", "~> 1.16"