Module theme 

Available on crate feature theme only.

Comprehensive theme system for ratatui-toolkit widgets.

This module provides a complete theming solution for TUI applications, with support for loading themes from JSON files in the opencode format.

Overview

The theme system consists of:

• AppTheme - The main theme struct with all widget colors
• ThemeVariant - Dark/light mode selection
• DiffColors - Colors for CodeDiff widget
• MarkdownColors - Colors for MarkdownWidget
• SyntaxColors - Colors for syntax highlighting
• loader - JSON theme file loading utilities

Builtin Themes

The crate includes 33 builtin themes that can be loaded by name:

use ratatui_toolkit::services::theme::{loader, ThemeVariant};

// Load a builtin theme
let theme = loader::load_builtin_theme("gruvbox", ThemeVariant::Dark)
    .expect("Failed to load theme");

// See all available themes
for name in loader::BUILTIN_THEMES {
    println!("{}", name);
}

Custom Themes

You can create custom themes from JSON files or strings:

use ratatui_toolkit::services::theme::{AppTheme, ThemeVariant};

let json = r#"{
  "defs": {
    "myPrimary": "#ff6600"
  },
  "theme": {
    "primary": { "dark": "myPrimary", "light": "myPrimary" }
  }
}"#;

let theme = AppTheme::from_json(json, ThemeVariant::Dark)
    .expect("Failed to parse theme");

JSON Format

The opencode theme format uses:

• defs: Named color definitions (e.g., "darkBg0": "#282828")
• theme: Semantic mappings with variant support

{
  "defs": {
    "colorName": "#hexcode"
  },
  "theme": {
    "primary": { "dark": "colorName", "light": "colorName" },
    "error": "#ff0000"
  }
}

Usage with Widgets

use ratatui::style::Style;
use ratatui_toolkit::services::theme::AppTheme;

let theme = AppTheme::default();

// Use UI colors
let primary_style = Style::default().fg(theme.primary);
let error_style = Style::default().fg(theme.error);

// Use diff colors
let added_style = Style::default().fg(theme.diff.added);

// Use markdown colors
let heading_style = Style::default().fg(theme.markdown.heading);

Re-exports

pub use app_theme::AppTheme;

pub use diff_colors::DiffColors;

pub use markdown_colors::MarkdownColors;

pub use syntax_colors::SyntaxColors;

pub use theme_variant::ThemeVariant;

Modules

app_theme

Application theme module for comprehensive TUI theming.

diff_colors

Diff colors module for CodeDiff widget theming.

loader

Theme loader module for parsing opencode theme JSON files.

markdown_colors

Markdown colors module for MarkdownWidget theming.

persistence

Theme persistence for saving and loading user theme preferences.

syntax_colors

Syntax colors module for code syntax highlighting.

theme_variant

Theme variant module for light and dark mode support.