implement a extendable color palette and improve config

Author: vacarsu

lib/scenic/color.ex

@@ -4,6 +4,8 @@
 #
 
 defmodule Scenic.Color do
+  alias Scenic.Themes
+
   @named_colors %{
     alice_blue: {0xF0, 0xF8, 0xFF},
     antique_white: {0xFA, 0xEB, 0xD7},
@@ -173,7 +175,7 @@ defmodule Scenic.Color do
 
   Most of the time, you will use one of the pre-defined named colors from the
   Named Colors table. However, there are times when you want to work with
-  other color formats ranging from simple grayscale to rgb to hsl. 
+  other color formats ranging from simple grayscale to rgb to hsl.
 
   The following formats are all supported by the `Scenic.Color` module.
   The values of r, g, b, and a are integers between 0 and 255.
@@ -616,7 +618,7 @@ defmodule Scenic.Color do
   @doc """
   Return map of all named colors and their values
   """
-  def named(), do: @named_colors
+  def named(), do: Themes.get_palette()
 
   # --------------------------------------------------------
   # @doc """

lib/scenic/component/button.ex

@@ -167,9 +167,12 @@ defmodule Scenic.Component.Button do
         nil -> Themes.preset({:scenic, :primary})
         {:scenic, :dark} -> Themes.preset({:scenic, :primary})
         {:scenic, :light} -> Themes.preset({:scenic, :primary})
-        theme -> theme
+        theme ->
+          case Themes.normalize(theme) do
+            nil -> Themes.preset({:scenic, :primary})
+            theme -> theme
+          end
       end
-      |> Themes.normalize()
 
     # font related info
     font = Keyword.get(styles, :font, @default_font)

lib/scenic/palette.ex

@@ -0,0 +1,155 @@
+defmodule Scenic.Palette do
+  @palette %{
+    alice_blue: {0xF0, 0xF8, 0xFF},
+    antique_white: {0xFA, 0xEB, 0xD7},
+    aqua: {0x00, 0xFF, 0xFF},
+    aquamarine: {0x7F, 0xFF, 0xD4},
+    azure: {0xF0, 0xFF, 0xFF},
+    beige: {0xF5, 0xF5, 0xDC},
+    bisque: {0xFF, 0xE4, 0xC4},
+    black: {0x00, 0x00, 0x00},
+    blanched_almond: {0xFF, 0xEB, 0xCD},
+    blue: {0x00, 0x00, 0xFF},
+    blue_violet: {0x8A, 0x2B, 0xE2},
+    brown: {0xA5, 0x2A, 0x2A},
+    burly_wood: {0xDE, 0xB8, 0x87},
+    cadet_blue: {0x5F, 0x9E, 0xA0},
+    chartreuse: {0x7F, 0xFF, 0x00},
+    chocolate: {0xD2, 0x69, 0x1E},
+    coral: {0xFF, 0x7F, 0x50},
+    cornflower_blue: {0x64, 0x95, 0xED},
+    cornsilk: {0xFF, 0xF8, 0xDC},
+    crimson: {0xDC, 0x14, 0x3C},
+    cyan: {0x00, 0xFF, 0xFF},
+    dark_blue: {0x00, 0x00, 0x8B},
+    dark_cyan: {0x00, 0x8B, 0x8B},
+    dark_golden_rod: {0xB8, 0x86, 0x0B},
+    dark_gray: {0xA9, 0xA9, 0xA9},
+    dark_grey: {0xA9, 0xA9, 0xA9},
+    dark_green: {0x00, 0x64, 0x00},
+    dark_khaki: {0xBD, 0xB7, 0x6B},
+    dark_magenta: {0x8B, 0x00, 0x8B},
+    dark_olive_green: {0x55, 0x6B, 0x2F},
+    dark_orange: {0xFF, 0x8C, 0x00},
+    dark_orchid: {0x99, 0x32, 0xCC},
+    dark_red: {0x8B, 0x00, 0x00},
+    dark_salmon: {0xE9, 0x96, 0x7A},
+    dark_sea_green: {0x8F, 0xBC, 0x8F},
+    dark_slate_blue: {0x48, 0x3D, 0x8B},
+    dark_slate_gray: {0x2F, 0x4F, 0x4F},
+    dark_slate_grey: {0x2F, 0x4F, 0x4F},
+    dark_turquoise: {0x00, 0xCE, 0xD1},
+    dark_violet: {0x94, 0x00, 0xD3},
+    deep_pink: {0xFF, 0x14, 0x93},
+    deep_sky_blue: {0x00, 0xBF, 0xFF},
+    dim_gray: {0x69, 0x69, 0x69},
+    dim_grey: {0x69, 0x69, 0x69},
+    dodger_blue: {0x1E, 0x90, 0xFF},
+    fire_brick: {0xB2, 0x22, 0x22},
+    floral_white: {0xFF, 0xFA, 0xF0},
+    forest_green: {0x22, 0x8B, 0x22},
+    fuchsia: {0xFF, 0x00, 0xFF},
+    gainsboro: {0xDC, 0xDC, 0xDC},
+    ghost_white: {0xF8, 0xF8, 0xFF},
+    gold: {0xFF, 0xD7, 0x00},
+    golden_rod: {0xDA, 0xA5, 0x20},
+    gray: {0x80, 0x80, 0x80},
+    grey: {0x80, 0x80, 0x80},
+    green: {0x00, 0x80, 0x00},
+    green_yellow: {0xAD, 0xFF, 0x2F},
+    honey_dew: {0xF0, 0xFF, 0xF0},
+    hot_pink: {0xFF, 0x69, 0xB4},
+    indian_red: {0xCD, 0x5C, 0x5C},
+    indigo: {0x4B, 0x00, 0x82},
+    ivory: {0xFF, 0xFF, 0xF0},
+    khaki: {0xF0, 0xE6, 0x8C},
+    lavender: {0xE6, 0xE6, 0xFA},
+    lavender_blush: {0xFF, 0xF0, 0xF5},
+    lawn_green: {0x7C, 0xFC, 0x00},
+    lemon_chiffon: {0xFF, 0xFA, 0xCD},
+    light_blue: {0xAD, 0xD8, 0xE6},
+    light_coral: {0xF0, 0x80, 0x80},
+    light_cyan: {0xE0, 0xFF, 0xFF},
+    light_golden_rod: {0xFA, 0xFA, 0xD2},
+    light_golden_rod_yellow: {0xFA, 0xFA, 0xD2},
+    light_gray: {0xD3, 0xD3, 0xD3},
+    light_grey: {0xD3, 0xD3, 0xD3},
+    light_green: {0x90, 0xEE, 0x90},
+    light_pink: {0xFF, 0xB6, 0xC1},
+    light_salmon: {0xFF, 0xA0, 0x7A},
+    light_sea_green: {0x20, 0xB2, 0xAA},
+    light_sky_blue: {0x87, 0xCE, 0xFA},
+    light_slate_gray: {0x77, 0x88, 0x99},
+    light_slate_grey: {0x77, 0x88, 0x99},
+    light_steel_blue: {0xB0, 0xC4, 0xDE},
+    light_yellow: {0xFF, 0xFF, 0xE0},
+    lime: {0x00, 0xFF, 0x00},
+    lime_green: {0x32, 0xCD, 0x32},
+    linen: {0xFA, 0xF0, 0xE6},
+    magenta: {0xFF, 0x00, 0xFF},
+    maroon: {0x80, 0x00, 0x00},
+    medium_aqua_marine: {0x66, 0xCD, 0xAA},
+    medium_blue: {0x00, 0x00, 0xCD},
+    medium_orchid: {0xBA, 0x55, 0xD3},
+    medium_purple: {0x93, 0x70, 0xDB},
+    medium_sea_green: {0x3C, 0xB3, 0x71},
+    medium_slate_blue: {0x7B, 0x68, 0xEE},
+    medium_spring_green: {0x00, 0xFA, 0x9A},
+    medium_turquoise: {0x48, 0xD1, 0xCC},
+    medium_violet_red: {0xC7, 0x15, 0x85},
+    midnight_blue: {0x19, 0x19, 0x70},
+    mint_cream: {0xF5, 0xFF, 0xFA},
+    misty_rose: {0xFF, 0xE4, 0xE1},
+    moccasin: {0xFF, 0xE4, 0xB5},
+    navajo_white: {0xFF, 0xDE, 0xAD},
+    navy: {0x00, 0x00, 0x80},
+    old_lace: {0xFD, 0xF5, 0xE6},
+    olive: {0x80, 0x80, 0x00},
+    olive_drab: {0x6B, 0x8E, 0x23},
+    orange: {0xFF, 0xA5, 0x00},
+    orange_red: {0xFF, 0x45, 0x00},
+    orchid: {0xDA, 0x70, 0xD6},
+    pale_golden_rod: {0xEE, 0xE8, 0xAA},
+    pale_green: {0x98, 0xFB, 0x98},
+    pale_turquoise: {0xAF, 0xEE, 0xEE},
+    pale_violet_red: {0xDB, 0x70, 0x93},
+    papaya_whip: {0xFF, 0xEF, 0xD5},
+    peach_puff: {0xFF, 0xDA, 0xB9},
+    peru: {0xCD, 0x85, 0x3F},
+    pink: {0xFF, 0xC0, 0xCB},
+    plum: {0xDD, 0xA0, 0xDD},
+    powder_blue: {0xB0, 0xE0, 0xE6},
+    purple: {0x80, 0x00, 0x80},
+    rebecca_purple: {0x66, 0x33, 0x99},
+    red: {0xFF, 0x00, 0x00},
+    rosy_brown: {0xBC, 0x8F, 0x8F},
+    royal_blue: {0x41, 0x69, 0xE1},
+    saddle_brown: {0x8B, 0x45, 0x13},
+    salmon: {0xFA, 0x80, 0x72},
+    sandy_brown: {0xF4, 0xA4, 0x60},
+    sea_green: {0x2E, 0x8B, 0x57},
+    sea_shell: {0xFF, 0xF5, 0xEE},
+    sienna: {0xA0, 0x52, 0x2D},
+    silver: {0xC0, 0xC0, 0xC0},
+    sky_blue: {0x87, 0xCE, 0xEB},
+    slate_blue: {0x6A, 0x5A, 0xCD},
+    slate_gray: {0x70, 0x80, 0x90},
+    slate_grey: {0x70, 0x80, 0x90},
+    snow: {0xFF, 0xFA, 0xFA},
+    spring_green: {0x00, 0xFF, 0x7F},
+    steel_blue: {0x46, 0x82, 0xB4},
+    tan: {0xD2, 0xB4, 0x8C},
+    teal: {0x00, 0x80, 0x80},
+    thistle: {0xD8, 0xBF, 0xD8},
+    tomato: {0xFF, 0x63, 0x47},
+    turquoise: {0x40, 0xE0, 0xD0},
+    violet: {0xEE, 0x82, 0xEE},
+    wheat: {0xF5, 0xDE, 0xB3},
+    white: {0xFF, 0xFF, 0xFF},
+    white_smoke: {0xF5, 0xF5, 0xF5},
+    yellow: {0xFF, 0xFF, 0x00},
+    yellow_green: {0x9A, 0xCD, 0x32}
+  }
+
+  def get(), do: @palette
+end

lib/scenic/themes.ex

@@ -1,4 +1,5 @@
 defmodule Scenic.Themes do
+  alias Scenic.Palette
   @moduledoc """
   Manages theme libraries by registering your map of themes to a library key.
   By registering themes in this way you can safely pull in themes from external libraries,
@@ -31,7 +32,7 @@ defmodule Scenic.Themes do
     schema [:surface] # add additional required keys to your theme
 
     use Scenic.Themes,
-      sources: [
+      [
         {:scenic, Scenic.Themes"},
         {:my_app, load()}
       ]
@@ -49,40 +50,73 @@ defmodule Scenic.Themes do
 
   Now themes are passed around scenic in the form of `{:library_name, :theme_name}` as opposed to just :theme_name.
   """
-  @callback load() :: {map, list} | map
+  @callback load() :: keyword
   @optional_callbacks load: 0
 
-  defmacro __using__(using_opts \\ []) do
+  defmacro __using__(sources \\ []) do
     quote do
       alias Scenic.Primitive.Style.Paint.Color
       @behaviour Scenic.Themes
-      @sources Keyword.get(unquote(using_opts), :sources, [])
+      @opts_schema [
+        name: [required: true, type: :atom],
+        themes: [required: true, type: :any],
+        schema: [required: false, type: :any],
+        palette: [required: false, type: :any]
+      ]
       @default_schema [:text, :background, :border, :active, :thumb, :focus]
-
-      @library_themes Enum.reduce(@sources, %{}, fn
-        {lib, module}, acc when is_atom(module) ->
-          case module.load() do
-            {themes, schema} ->
-              Map.put_new(acc, lib, {themes, List.flatten([@default_schema | schema])})
-            themes ->
-              Map.put_new(acc, lib, {themes, @default_schema})
-          end
-        {lib, {themes, schema}}, acc ->
-          Map.put_new(acc, lib, {themes, List.flatten([@default_schema | schema])})
-        {lib, themes}, acc ->
-          Map.put_new(acc, lib, {themes, @default_schema})
-        _, acc -> acc
+      @palette %{}
+
+      @library_themes Enum.reduce(unquote(sources), %{}, fn lib_opts, acc ->
+        case NimbleOptions.validate(lib_opts, @opts_schema) do
+          {:ok, lib_opts} ->
+            name = lib_opts[:name]
+            themes = lib_opts[:themes]
+            schema = lib_opts[:schema] || []
+            palette = lib_opts[:palette] || %{}
+            @palette Map.merge(@palette, palette)
+            case themes do
+              themes when is_map(themes) ->
+                # not a module so we can load in the settings directly
+                Map.put_new(acc, name, {themes, List.flatten([@default_schema | schema])})
+              themes ->
+                # this is a module so we have to load the settings
+                lib_opts = themes.load()
+                themes = lib_opts[:themes]
+                schema = lib_opts[:schema] || []
+                palette = lib_opts[:palette] || %{}
+                IO.inspect palette
+                @palette Map.merge(@palette, palette)
+                Map.put_new(acc, name, {themes, List.flatten([@default_schema | schema])})
+            end
+          {:error, error} ->
+            raise Exception.message(error)
+        end
       end)
 
+      # validate the passed options
       def validate(theme)
       def validate({lib, theme_name} = lib_theme) when is_atom(theme_name) do
-        {_, schema} = Map.get(@library_themes, lib)
-        case normalize(lib_theme) do
-          theme ->
+        case Map.get(@library_themes, lib) do
+          {themes, schema} ->
             # validate against the schema
-            case validate(theme, schema) do
-              {:ok, _} -> {:ok, lib_theme}
-              error -> error
+            case Map.get(themes, theme_name) do
+              nil ->
+                {
+                  :error,
+                  """
+                  #{IO.ANSI.red()}Invalid theme specification
+                  Received: #{inspect(theme_name)}
+                  #{IO.ANSI.yellow()}
+                  The theme could not be found in library #{inspect(lib)}.
+                  Ensure you got the name correct.
+                  #{IO.ANSI.default_color()}
+                  """
+                }
+              theme ->
+                case validate(theme, schema) do
+                  {:ok, _} -> {:ok, lib_theme}
+                  error -> error
+                end
             end
           nil ->
             {
@@ -177,10 +211,23 @@ defmodule Scenic.Themes do
         }
       end
 
+      @doc false
+      def get_schema(lib) do
+        case Map.get(@library_themes, lib) do
+          {_, schema} -> schema
+          nil -> nil
+        end
+      end
+
+      @doc false
+      def get_palette() do
+        @palette
+      end
+
       @doc false
       def normalize({lib, theme_name}) when is_atom(theme_name) do
         case Map.get(@library_themes, lib) do
-          {themes, schema} -> Map.get(themes, theme_name)
+          {themes, _schema} -> Map.get(themes, theme_name)
           nil -> nil
         end
       end
@@ -236,10 +283,8 @@ defmodule Scenic.Themes do
         Example Themes module that includes an optional alias:
 
           defmodule MyApplication.Themes do
-            use Scenic.Assets.Static,
-              otp_app: :my_application,
-              alias: [
-                scenic: Scenic.Themes,
+            use Scenic.Themes, [
+                [name: scenic: themes: Scenic.Themes],
               ]
           end
 
@@ -251,15 +296,34 @@ defmodule Scenic.Themes do
     end
   end
 
-  @doc false
+  @spec validate({atom, atom} | {atom, map} | map) :: {:ok, term} | {:error, term}
+  @doc """
+  Validate a theme
+  """
   def validate(theme), do: module().validate(theme)
 
+  @spec get_schema(atom) :: list
+  @doc """
+  Retrieve a library's schema
+  """
+  def get_schema(lib), do: module().get_schema(lib)
+
+  @spec normalize({atom, atom} | map) :: map | nil
   @doc false
   def normalize(theme), do: module().normalize(theme)
 
-  @doc false
+  @spec preset({atom, atom} | map) :: map | nil
+  @doc """
+  Get a theme.
+  """
   def preset(theme), do: module().preset(theme)
 
+  @spec get_palette() :: map
+  @doc """
+  Get the palette of colors.
+  """
+  def get_palette(), do: module().get_palette()
+
   @theme_light %{
     text: :black,
     background: :white,
@@ -300,5 +364,5 @@ defmodule Scenic.Themes do
   }
 
   @doc false
-  def load(), do: @themes
+  def load(), do: [name: :scenic, themes: @themes, palette: Palette.get()]
 end