Add Style, StyleLabel and ColorTheme

src/main.rs

@@ -3,6 +3,7 @@
 
 mod infra;
 mod language;
+mod style;
 
 fn main() {
     bug!("not yet implemented");

src/style.rs

@@ -0,0 +1,204 @@
+use crate::infra::SynlessBug;
+use partial_pretty_printer as ppp;
+
+#[derive(Debug, Clone)]
+pub struct Style {
+    color: Option<(Base16Color, Priority)>,
+    bold: Option<(bool, Priority)>,
+    italic: Option<(bool, Priority)>,
+    underlined: Option<(bool, Priority)>,
+    cursor: Option<CursorHalf>,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum Priority {
+    High,
+    Low,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum CursorHalf {
+    Left,
+    Right,
+}
+
+#[derive(Debug, Clone)]
+pub enum StyleLabel {
+    Open,
+    Close,
+    Properties {
+        color: Option<Base16Color>,
+        bold: Option<bool>,
+        italic: Option<bool>,
+        underlined: Option<bool>,
+        priority: Priority,
+    },
+}
+
+/// A 24-bit RGB color.
+#[derive(Debug, Clone, Copy)]
+pub struct Rgb {
+    pub red: u8,
+    pub green: u8,
+    pub blue: u8,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum Base16Color {
+    /// Default Background
+    Base00,
+    /// Lighter Background (Used for status bars)
+    Base01,
+    /// Selection Background
+    Base02,
+    /// Comments, Invisibles, Line Highlighting
+    Base03,
+    /// Dark Foreground (Used for status bars)
+    Base04,
+    /// Default Foreground, Caret, Delimiters, Operators
+    Base05,
+    /// Light Foreground (Not often used)
+    Base06,
+    /// Light Background (Not often used)
+    Base07,
+    /// Variables, XML Tags, Markup Link Text, Markup Lists, Diff Deleted
+    Base08,
+    /// Integers, Boolean, Constants, XML Attributes, Markup Link Url
+    Base09,
+    /// Classes, Markup Bold, Search Text Background
+    Base0A,
+    /// Strings, Inherited Class, Markup Code, Diff Inserted
+    Base0B,
+    /// Support, Regular Expressions, Escape Characters, Markup Quotes
+    Base0C,
+    /// Functions, Methods, Attribute IDs, Headings
+    Base0D,
+    /// Keywords, Storage, Selector, Markup Italic, Diff Changed
+    Base0E,
+    /// Deprecated, Opening/Closing Embedded Language Tags, e.g. <?php ?>
+    Base0F,
+}
+
+/// A color theme that maps [Base16](https://github.com/chriskempson/base16) color names to RGB
+/// color values.
+#[derive(Debug, Clone)]
+#[allow(non_snake_case)]
+pub struct ColorTheme {
+    /// Default Background
+    pub base00: Rgb,
+    /// Lighter Background (Used for status bars)
+    pub base01: Rgb,
+    /// Selection Background
+    pub base02: Rgb,
+    /// Comments, Invisibles, Line Highlighting
+    pub base03: Rgb,
+    /// Dark Foreground (Used for status bars)
+    pub base04: Rgb,
+    /// Default Foreground, Caret, Delimiters, Operators
+    pub base05: Rgb,
+    /// Light Foreground (Not often used)
+    pub base06: Rgb,
+    /// Light Background (Not often used)
+    pub base07: Rgb,
+    /// Variables, XML Tags, Markup Link Text, Markup Lists, Diff Deleted
+    pub base08: Rgb,
+    /// Integers, Boolean, Constants, XML Attributes, Markup Link Url
+    pub base09: Rgb,
+    /// Classes, Markup Bold, Search Text Background
+    pub base0A: Rgb,
+    /// Strings, Inherited Class, Markup Code, Diff Inserted
+    pub base0B: Rgb,
+    /// Support, Regular Expressions, Escape Characters, Markup Quotes
+    pub base0C: Rgb,
+    /// Functions, Methods, Attribute IDs, Headings
+    pub base0D: Rgb,
+    /// Keywords, Storage, Selector, Markup Italic, Diff Changed
+    pub base0E: Rgb,
+    /// Deprecated, Opening/Closing Embedded Language Tags, e.g. <?php ?>
+    pub base0F: Rgb,
+}
+
+fn prioritize<T>(
+    outer: Option<(T, Priority)>,
+    inner: Option<(T, Priority)>,
+) -> Option<(T, Priority)> {
+    match (outer.as_ref().map(|x| x.1), inner.as_ref().map(|x| x.1)) {
+        (None, _) => inner,
+        (_, None) => outer,
+        (Some(Priority::Low), Some(_)) => inner,
+        (Some(Priority::High), Some(Priority::Low)) => outer,
+        (Some(Priority::High), Some(Priority::High)) => inner,
+    }
+}
+
+impl ppp::Style for Style {
+    fn combine(outer: &Self, inner: &Self) -> Self {
+        Style {
+            cursor: outer.cursor.or(inner.cursor),
+            color: prioritize(outer.color, inner.color),
+            bold: prioritize(outer.bold, inner.bold),
+            italic: prioritize(outer.italic, inner.italic),
+            underlined: prioritize(outer.underlined, inner.underlined),
+        }
+    }
+}
+
+impl ColorTheme {
+    /// The "default dark" Base16 colorscheme, by Chris Kempson (http://chriskempson.com)
+    pub fn default_dark() -> ColorTheme {
+        ColorTheme {
+            base00: Rgb::from_hex("#181818").bug(),
+            base01: Rgb::from_hex("#282828").bug(),
+            base02: Rgb::from_hex("#383838").bug(),
+            base03: Rgb::from_hex("#585858").bug(),
+            base04: Rgb::from_hex("#b8b8b8").bug(),
+            base05: Rgb::from_hex("#d8d8d8").bug(),
+            base06: Rgb::from_hex("#e8e8e8").bug(),
+            base07: Rgb::from_hex("#f8f8f8").bug(),
+            base08: Rgb::from_hex("#ab4642").bug(),
+            base09: Rgb::from_hex("#dc9656").bug(),
+            base0A: Rgb::from_hex("#f7ca88").bug(),
+            base0B: Rgb::from_hex("#a1b56c").bug(),
+            base0C: Rgb::from_hex("#86c1b9").bug(),
+            base0D: Rgb::from_hex("#7cafc2").bug(),
+            base0E: Rgb::from_hex("#ba8baf").bug(),
+            base0F: Rgb::from_hex("#a16946").bug(),
+        }
+    }
+
+    fn color(&self, color: Base16Color) -> Rgb {
+        match color {
+            Base16Color::Base00 => self.base00,
+            Base16Color::Base01 => self.base01,
+            Base16Color::Base02 => self.base02,
+            Base16Color::Base03 => self.base03,
+            Base16Color::Base04 => self.base04,
+            Base16Color::Base05 => self.base05,
+            Base16Color::Base06 => self.base06,
+            Base16Color::Base07 => self.base07,
+            Base16Color::Base08 => self.base08,
+            Base16Color::Base09 => self.base09,
+            Base16Color::Base0A => self.base0A,
+            Base16Color::Base0B => self.base0B,
+            Base16Color::Base0C => self.base0C,
+            Base16Color::Base0D => self.base0D,
+            Base16Color::Base0E => self.base0E,
+            Base16Color::Base0F => self.base0F,
+        }
+    }
+}
+
+impl Rgb {
+    /// Construct an Rgb color from a string of the form "#FFFFFF".
+    fn from_hex(hex_color: &str) -> Option<Rgb> {
+        let to_int = |inclusive_range: (usize, usize)| -> Option<u8> {
+            u8::from_str_radix(hex_color.get(inclusive_range.0..=inclusive_range.1)?, 16).ok()
+        };
+
+        Some(Rgb {
+            red: to_int((1, 2))?,
+            green: to_int((3, 4))?,
+            blue: to_int((5, 6))?,
+        })
+    }
+}