Merge pull request #2312 from iced-rs/theming-reloaded

Theming reloaded

9 files changed, 343 insertions, 51 deletions

diff --git a/core/Cargo.toml b/core/Cargo.toml
index 2360e822..c273fcb4 100644
--- a/core/Cargo.toml
+++ b/core/Cargo.toml
@@ -15,14 +15,13 @@ bitflags.workspace = true
 glam.workspace = true
 log.workspace = true
 num-traits.workspace = true
+once_cell.workspace = true
+palette.workspace = true
 smol_str.workspace = true
 thiserror.workspace = true
 web-time.workspace = true
 xxhash-rust.workspace = true
 
-palette.workspace = true
-palette.optional = true
-
 [target.'cfg(windows)'.dependencies]
 raw-window-handle.workspace = true
 
diff --git a/core/src/background.rs b/core/src/background.rs
index 347c52c0..eb4b5021 100644
--- a/core/src/background.rs
+++ b/core/src/background.rs
@@ -11,6 +11,19 @@ pub enum Background {
     // TODO: Add image variant
 }
 
+impl Background {
+    /// Scales the the alpha channel of the [`Background`] by the given
+    /// factor.
+    pub fn scale_alpha(self, factor: f32) -> Self {
+        match self {
+            Self::Color(color) => Self::Color(color.scale_alpha(factor)),
+            Self::Gradient(gradient) => {
+                Self::Gradient(gradient.scale_alpha(factor))
+            }
+        }
+    }
+}
+
 impl From<Color> for Background {
     fn from(color: Color) -> Self {
         Background::Color(color)
diff --git a/core/src/border.rs b/core/src/border.rs
index 64262471..2df24988 100644
--- a/core/src/border.rs
+++ b/core/src/border.rs
@@ -1,5 +1,5 @@
 //! Draw lines around containers.
-use crate::Color;
+use crate::{Color, Pixels};
 
 /// A border.
 #[derive(Debug, Clone, Copy, PartialEq, Default)]
@@ -15,11 +15,38 @@ pub struct Border {
 }
 
 impl Border {
-    /// Creates a new default [`Border`] with the given [`Radius`].
-    pub fn with_radius(radius: impl Into<Radius>) -> Self {
+    /// Creates a new default rounded [`Border`] with the given [`Radius`].
+    ///
+    /// ```
+    /// # use iced_core::Border;
+    /// #
+    /// assert_eq!(Border::rounded(10), Border::default().with_radius(10));
+    /// ```
+    pub fn rounded(radius: impl Into<Radius>) -> Self {
+        Self::default().with_radius(radius)
+    }
+
+    /// Updates the [`Color`] of the [`Border`].
+    pub fn with_color(self, color: impl Into<Color>) -> Self {
+        Self {
+            color: color.into(),
+            ..self
+        }
+    }
+
+    /// Updates the [`Radius`] of the [`Border`].
+    pub fn with_radius(self, radius: impl Into<Radius>) -> Self {
         Self {
             radius: radius.into(),
-            ..Self::default()
+            ..self
+        }
+    }
+
+    /// Updates the width of the [`Border`].
+    pub fn with_width(self, width: impl Into<Pixels>) -> Self {
+        Self {
+            width: width.into().0,
+            ..self
         }
     }
 }
diff --git a/core/src/color.rs b/core/src/color.rs
index b8db322f..4e79defb 100644
--- a/core/src/color.rs
+++ b/core/src/color.rs
@@ -1,4 +1,3 @@
-#[cfg(feature = "palette")]
 use palette::rgb::{Srgb, Srgba};
 
 /// A color in the `sRGB` color space.
@@ -151,6 +150,14 @@ impl Color {
     pub fn inverse(self) -> Color {
         Color::new(1.0f32 - self.r, 1.0f32 - self.g, 1.0f32 - self.b, self.a)
     }
+
+    /// Scales the alpha channel of the [`Color`] by the given factor.
+    pub fn scale_alpha(self, factor: f32) -> Color {
+        Self {
+            a: self.a * factor,
+            ..self
+        }
+    }
 }
 
 impl From<[f32; 3]> for Color {
@@ -202,7 +209,6 @@ macro_rules! color {
     }};
 }
 
-#[cfg(feature = "palette")]
 /// Converts from palette's `Rgba` type to a [`Color`].
 impl From<Srgba> for Color {
     fn from(rgba: Srgba) -> Self {
@@ -210,7 +216,6 @@ impl From<Srgba> for Color {
     }
 }
 
-#[cfg(feature = "palette")]
 /// Converts from [`Color`] to palette's `Rgba` type.
 impl From<Color> for Srgba {
     fn from(c: Color) -> Self {
@@ -218,7 +223,6 @@ impl From<Color> for Srgba {
     }
 }
 
-#[cfg(feature = "palette")]
 /// Converts from palette's `Rgb` type to a [`Color`].
 impl From<Srgb> for Color {
     fn from(rgb: Srgb) -> Self {
@@ -226,7 +230,6 @@ impl From<Srgb> for Color {
     }
 }
 
-#[cfg(feature = "palette")]
 /// Converts from [`Color`] to palette's `Rgb` type.
 impl From<Color> for Srgb {
     fn from(c: Color) -> Self {
@@ -234,7 +237,6 @@ impl From<Color> for Srgb {
     }
 }
 
-#[cfg(feature = "palette")]
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/core/src/gradient.rs b/core/src/gradient.rs
index 4711b044..ccae0bce 100644
--- a/core/src/gradient.rs
+++ b/core/src/gradient.rs
@@ -12,17 +12,13 @@ pub enum Gradient {
 }
 
 impl Gradient {
-    /// Adjust the opacity of the gradient by a multiplier applied to each color stop.
-    pub fn mul_alpha(mut self, alpha_multiplier: f32) -> Self {
-        match &mut self {
+    /// Scales the alpha channel of the [`Gradient`] by the given factor.
+    pub fn scale_alpha(self, factor: f32) -> Self {
+        match self {
             Gradient::Linear(linear) => {
-                for stop in linear.stops.iter_mut().flatten() {
-                    stop.color.a *= alpha_multiplier;
-                }
+                Gradient::Linear(linear.scale_alpha(factor))
             }
         }
-
-        self
     }
 }
 
@@ -100,4 +96,14 @@ impl Linear {
 
         self
     }
+
+    /// Scales the alpha channel of the [`Linear`] gradient by the given
+    /// factor.
+    pub fn scale_alpha(mut self, factor: f32) -> Self {
+        for stop in self.stops.iter_mut().flatten() {
+            stop.color.a *= factor;
+        }
+
+        self
+    }
 }
diff --git a/core/src/lib.rs b/core/src/lib.rs
index 002336ee..d076413e 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -30,6 +30,7 @@ pub mod overlay;
 pub mod renderer;
 pub mod svg;
 pub mod text;
+pub mod theme;
 pub mod time;
 pub mod touch;
 pub mod widget;
@@ -76,6 +77,7 @@ pub use shadow::Shadow;
 pub use shell::Shell;
 pub use size::Size;
 pub use text::Text;
+pub use theme::Theme;
 pub use transformation::Transformation;
 pub use vector::Vector;
 pub use widget::Widget;
diff --git a/core/src/theme.rs b/core/src/theme.rs
new file mode 100644
index 00000000..21ba2a37
--- /dev/null
+++ b/core/src/theme.rs
@@ -0,0 +1,221 @@
+//! Use the built-in theme and styles.
+pub mod palette;
+
+pub use palette::Palette;
+
+use std::fmt;
+use std::sync::Arc;
+
+/// A built-in theme.
+#[derive(Debug, Clone, PartialEq, Default)]
+pub enum Theme {
+    /// The built-in light variant.
+    #[default]
+    Light,
+    /// The built-in dark variant.
+    Dark,
+    /// The built-in Dracula variant.
+    Dracula,
+    /// The built-in Nord variant.
+    Nord,
+    /// The built-in Solarized Light variant.
+    SolarizedLight,
+    /// The built-in Solarized Dark variant.
+    SolarizedDark,
+    /// The built-in Gruvbox Light variant.
+    GruvboxLight,
+    /// The built-in Gruvbox Dark variant.
+    GruvboxDark,
+    /// The built-in Catppuccin Latte variant.
+    CatppuccinLatte,
+    /// The built-in Catppuccin Frappé variant.
+    CatppuccinFrappe,
+    /// The built-in Catppuccin Macchiato variant.
+    CatppuccinMacchiato,
+    /// The built-in Catppuccin Mocha variant.
+    CatppuccinMocha,
+    /// The built-in Tokyo Night variant.
+    TokyoNight,
+    /// The built-in Tokyo Night Storm variant.
+    TokyoNightStorm,
+    /// The built-in Tokyo Night Light variant.
+    TokyoNightLight,
+    /// The built-in Kanagawa Wave variant.
+    KanagawaWave,
+    /// The built-in Kanagawa Dragon variant.
+    KanagawaDragon,
+    /// The built-in Kanagawa Lotus variant.
+    KanagawaLotus,
+    /// The built-in Moonfly variant.
+    Moonfly,
+    /// The built-in Nightfly variant.
+    Nightfly,
+    /// The built-in Oxocarbon variant.
+    Oxocarbon,
+    /// A [`Theme`] that uses a [`Custom`] palette.
+    Custom(Arc<Custom>),
+}
+
+impl Theme {
+    /// A list with all the defined themes.
+    pub const ALL: &'static [Self] = &[
+        Self::Light,
+        Self::Dark,
+        Self::Dracula,
+        Self::Nord,
+        Self::SolarizedLight,
+        Self::SolarizedDark,
+        Self::GruvboxLight,
+        Self::GruvboxDark,
+        Self::CatppuccinLatte,
+        Self::CatppuccinFrappe,
+        Self::CatppuccinMacchiato,
+        Self::CatppuccinMocha,
+        Self::TokyoNight,
+        Self::TokyoNightStorm,
+        Self::TokyoNightLight,
+        Self::KanagawaWave,
+        Self::KanagawaDragon,
+        Self::KanagawaLotus,
+        Self::Moonfly,
+        Self::Nightfly,
+        Self::Oxocarbon,
+    ];
+
+    /// Creates a new custom [`Theme`] from the given [`Palette`].
+    pub fn custom(name: String, palette: Palette) -> Self {
+        Self::custom_with_fn(name, palette, palette::Extended::generate)
+    }
+
+    /// Creates a new custom [`Theme`] from the given [`Palette`], with
+    /// a custom generator of a [`palette::Extended`].
+    pub fn custom_with_fn(
+        name: String,
+        palette: Palette,
+        generate: impl FnOnce(Palette) -> palette::Extended,
+    ) -> Self {
+        Self::Custom(Arc::new(Custom::with_fn(name, palette, generate)))
+    }
+
+    /// Returns the [`Palette`] of the [`Theme`].
+    pub fn palette(&self) -> Palette {
+        match self {
+            Self::Light => Palette::LIGHT,
+            Self::Dark => Palette::DARK,
+            Self::Dracula => Palette::DRACULA,
+            Self::Nord => Palette::NORD,
+            Self::SolarizedLight => Palette::SOLARIZED_LIGHT,
+            Self::SolarizedDark => Palette::SOLARIZED_DARK,
+            Self::GruvboxLight => Palette::GRUVBOX_LIGHT,
+            Self::GruvboxDark => Palette::GRUVBOX_DARK,
+            Self::CatppuccinLatte => Palette::CATPPUCCIN_LATTE,
+            Self::CatppuccinFrappe => Palette::CATPPUCCIN_FRAPPE,
+            Self::CatppuccinMacchiato => Palette::CATPPUCCIN_MACCHIATO,
+            Self::CatppuccinMocha => Palette::CATPPUCCIN_MOCHA,
+            Self::TokyoNight => Palette::TOKYO_NIGHT,
+            Self::TokyoNightStorm => Palette::TOKYO_NIGHT_STORM,
+            Self::TokyoNightLight => Palette::TOKYO_NIGHT_LIGHT,
+            Self::KanagawaWave => Palette::KANAGAWA_WAVE,
+            Self::KanagawaDragon => Palette::KANAGAWA_DRAGON,
+            Self::KanagawaLotus => Palette::KANAGAWA_LOTUS,
+            Self::Moonfly => Palette::MOONFLY,
+            Self::Nightfly => Palette::NIGHTFLY,
+            Self::Oxocarbon => Palette::OXOCARBON,
+            Self::Custom(custom) => custom.palette,
+        }
+    }
+
+    /// Returns the [`palette::Extended`] of the [`Theme`].
+    pub fn extended_palette(&self) -> &palette::Extended {
+        match self {
+            Self::Light => &palette::EXTENDED_LIGHT,
+            Self::Dark => &palette::EXTENDED_DARK,
+            Self::Dracula => &palette::EXTENDED_DRACULA,
+            Self::Nord => &palette::EXTENDED_NORD,
+            Self::SolarizedLight => &palette::EXTENDED_SOLARIZED_LIGHT,
+            Self::SolarizedDark => &palette::EXTENDED_SOLARIZED_DARK,
+            Self::GruvboxLight => &palette::EXTENDED_GRUVBOX_LIGHT,
+            Self::GruvboxDark => &palette::EXTENDED_GRUVBOX_DARK,
+            Self::CatppuccinLatte => &palette::EXTENDED_CATPPUCCIN_LATTE,
+            Self::CatppuccinFrappe => &palette::EXTENDED_CATPPUCCIN_FRAPPE,
+            Self::CatppuccinMacchiato => {
+                &palette::EXTENDED_CATPPUCCIN_MACCHIATO
+            }
+            Self::CatppuccinMocha => &palette::EXTENDED_CATPPUCCIN_MOCHA,
+            Self::TokyoNight => &palette::EXTENDED_TOKYO_NIGHT,
+            Self::TokyoNightStorm => &palette::EXTENDED_TOKYO_NIGHT_STORM,
+            Self::TokyoNightLight => &palette::EXTENDED_TOKYO_NIGHT_LIGHT,
+            Self::KanagawaWave => &palette::EXTENDED_KANAGAWA_WAVE,
+            Self::KanagawaDragon => &palette::EXTENDED_KANAGAWA_DRAGON,
+            Self::KanagawaLotus => &palette::EXTENDED_KANAGAWA_LOTUS,
+            Self::Moonfly => &palette::EXTENDED_MOONFLY,
+            Self::Nightfly => &palette::EXTENDED_NIGHTFLY,
+            Self::Oxocarbon => &palette::EXTENDED_OXOCARBON,
+            Self::Custom(custom) => &custom.extended,
+        }
+    }
+}
+
+impl fmt::Display for Theme {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Light => write!(f, "Light"),
+            Self::Dark => write!(f, "Dark"),
+            Self::Dracula => write!(f, "Dracula"),
+            Self::Nord => write!(f, "Nord"),
+            Self::SolarizedLight => write!(f, "Solarized Light"),
+            Self::SolarizedDark => write!(f, "Solarized Dark"),
+            Self::GruvboxLight => write!(f, "Gruvbox Light"),
+            Self::GruvboxDark => write!(f, "Gruvbox Dark"),
+            Self::CatppuccinLatte => write!(f, "Catppuccin Latte"),
+            Self::CatppuccinFrappe => write!(f, "Catppuccin Frappé"),
+            Self::CatppuccinMacchiato => write!(f, "Catppuccin Macchiato"),
+            Self::CatppuccinMocha => write!(f, "Catppuccin Mocha"),
+            Self::TokyoNight => write!(f, "Tokyo Night"),
+            Self::TokyoNightStorm => write!(f, "Tokyo Night Storm"),
+            Self::TokyoNightLight => write!(f, "Tokyo Night Light"),
+            Self::KanagawaWave => write!(f, "Kanagawa Wave"),
+            Self::KanagawaDragon => write!(f, "Kanagawa Dragon"),
+            Self::KanagawaLotus => write!(f, "Kanagawa Lotus"),
+            Self::Moonfly => write!(f, "Moonfly"),
+            Self::Nightfly => write!(f, "Nightfly"),
+            Self::Oxocarbon => write!(f, "Oxocarbon"),
+            Self::Custom(custom) => custom.fmt(f),
+        }
+    }
+}
+
+/// A [`Theme`] with a customized [`Palette`].
+#[derive(Debug, Clone, PartialEq)]
+pub struct Custom {
+    name: String,
+    palette: Palette,
+    extended: palette::Extended,
+}
+
+impl Custom {
+    /// Creates a [`Custom`] theme from the given [`Palette`].
+    pub fn new(name: String, palette: Palette) -> Self {
+        Self::with_fn(name, palette, palette::Extended::generate)
+    }
+
+    /// Creates a [`Custom`] theme from the given [`Palette`] with
+    /// a custom generator of a [`palette::Extended`].
+    pub fn with_fn(
+        name: String,
+        palette: Palette,
+        generate: impl FnOnce(Palette) -> palette::Extended,
+    ) -> Self {
+        Self {
+            name,
+            palette,
+            extended: generate(palette),
+        }
+    }
+}
+
+impl fmt::Display for Custom {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.name)
+    }
+}
diff --git a/style/src/theme/palette.rs b/core/src/theme/palette.rs
index 15a964cd..985a54a8 100644
--- a/style/src/theme/palette.rs
+++ b/core/src/theme/palette.rs
@@ -1,5 +1,5 @@
 //! Define the colors of a theme.
-use crate::core::{color, Color};
+use crate::{color, Color};
 
 use once_cell::sync::Lazy;
 use palette::color_difference::Wcag21RelativeContrast;
diff --git a/core/src/widget/text.rs b/core/src/widget/text.rs
index 0796c4e4..a220127c 100644
--- a/core/src/widget/text.rs
+++ b/core/src/widget/text.rs
@@ -17,7 +17,6 @@ pub use text::{LineHeight, Shaping};
 #[allow(missing_debug_implementations)]
 pub struct Text<'a, Theme, Renderer>
 where
-    Theme: StyleSheet,
     Renderer: text::Renderer,
 {
     content: Cow<'a, str>,
@@ -29,12 +28,11 @@ where
     vertical_alignment: alignment::Vertical,
     font: Option<Renderer::Font>,
     shaping: Shaping,
-    style: Theme::Style,
+    style: Style<Theme>,
 }
 
 impl<'a, Theme, Renderer> Text<'a, Theme, Renderer>
 where
-    Theme: StyleSheet,
     Renderer: text::Renderer,
 {
     /// Create a new fragment of [`Text`] with the given contents.
@@ -49,7 +47,7 @@ where
             horizontal_alignment: alignment::Horizontal::Left,
             vertical_alignment: alignment::Vertical::Top,
             shaping: Shaping::Basic,
-            style: Default::default(),
+            style: Style::default(),
         }
     }
 
@@ -74,8 +72,20 @@ where
     }
 
     /// Sets the style of the [`Text`].
-    pub fn style(mut self, style: impl Into<Theme::Style>) -> Self {
-        self.style = style.into();
+    pub fn style(mut self, style: fn(&Theme) -> Appearance) -> Self {
+        self.style = Style::Themed(style);
+        self
+    }
+
+    /// Sets the [`Color`] of the [`Text`].
+    pub fn color(mut self, color: impl Into<Color>) -> Self {
+        self.style = Style::Colored(Some(color.into()));
+        self
+    }
+
+    /// Sets the [`Color`] of the [`Text`], if `Some`.
+    pub fn color_maybe(mut self, color: Option<impl Into<Color>>) -> Self {
+        self.style = Style::Colored(color.map(Into::into));
         self
     }
 
@@ -123,7 +133,6 @@ pub struct State<P: Paragraph>(P);
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Text<'a, Theme, Renderer>
 where
-    Theme: StyleSheet,
     Renderer: text::Renderer,
 {
     fn tag(&self) -> tree::Tag {
@@ -175,14 +184,12 @@ where
     ) {
         let state = tree.state.downcast_ref::<State<Renderer::Paragraph>>();
 
-        draw(
-            renderer,
-            style,
-            layout,
-            state,
-            theme.appearance(self.style.clone()),
-            viewport,
-        );
+        let appearance = match self.style {
+            Style::Themed(f) => f(theme),
+            Style::Colored(color) => Appearance { color },
+        };
+
+        draw(renderer, style, layout, state, appearance, viewport);
     }
 }
 
@@ -273,7 +280,7 @@ pub fn draw<Renderer>(
 impl<'a, Message, Theme, Renderer> From<Text<'a, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
-    Theme: StyleSheet + 'a,
+    Theme: 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(
@@ -285,7 +292,6 @@ where
 
 impl<'a, Theme, Renderer> Clone for Text<'a, Theme, Renderer>
 where
-    Theme: StyleSheet,
     Renderer: text::Renderer,
 {
     fn clone(&self) -> Self {
@@ -298,7 +304,7 @@ where
             horizontal_alignment: self.horizontal_alignment,
             vertical_alignment: self.vertical_alignment,
             font: self.font,
-            style: self.style.clone(),
+            style: self.style,
             shaping: self.shaping,
         }
     }
@@ -306,7 +312,6 @@ where
 
 impl<'a, Theme, Renderer> From<&'a str> for Text<'a, Theme, Renderer>
 where
-    Theme: StyleSheet,
     Renderer: text::Renderer,
 {
     fn from(content: &'a str) -> Self {
@@ -317,7 +322,7 @@ where
 impl<'a, Message, Theme, Renderer> From<&'a str>
     for Element<'a, Message, Theme, Renderer>
 where
-    Theme: StyleSheet + 'a,
+    Theme: 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(content: &'a str) -> Self {
@@ -325,15 +330,6 @@ where
     }
 }
 
-/// The style sheet of some text.
-pub trait StyleSheet {
-    /// The supported style of the [`StyleSheet`].
-    type Style: Default + Clone;
-
-    /// Produces the [`Appearance`] of some text.
-    fn appearance(&self, style: Self::Style) -> Appearance;
-}
-
 /// The apperance of some text.
 #[derive(Debug, Clone, Copy, Default)]
 pub struct Appearance {
@@ -342,3 +338,29 @@ pub struct Appearance {
     /// The default, `None`, means using the inherited color.
     pub color: Option<Color>,
 }
+
+#[derive(Debug)]
+enum Style<Theme> {
+    Themed(fn(&Theme) -> Appearance),
+    Colored(Option<Color>),
+}
+
+impl<Theme> Clone for Style<Theme> {
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<Theme> Copy for Style<Theme> {}
+
+impl<Theme> Default for Style<Theme> {
+    fn default() -> Self {
+        Style::Colored(None)
+    }
+}
+
+impl<Theme> From<fn(&Theme) -> Appearance> for Style<Theme> {
+    fn from(f: fn(&Theme) -> Appearance) -> Self {
+        Style::Themed(f)
+    }
+}