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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const THEME_SELECTOR_STRINGS = {
light: ":root.theme-light {",
dark: ":root.theme-dark {",
root: ":root {",
};
const THEME_PREF = "devtools.theme";
/**
* Takes a theme name and returns the contents of its variable rule block.
* The first time this runs fetches the variables CSS file and caches it.
*/
function getThemeFile(name) {
// If there's no theme expected for this name, use `light` as default.
const selector = THEME_SELECTOR_STRINGS[name] || THEME_SELECTOR_STRINGS.light;
// This is a pretty naive way to find the contents between:
// selector {
// name: val;
// }
// There is test coverage for this feature (browser_theme.js)
// so if an } is introduced in the variables file it will catch that.
let theme = variableFileContents;
theme = theme.substring(theme.indexOf(selector));
theme = theme.substring(0, theme.indexOf("}"));
return theme;
}
/**
* Returns the "auto" theme.
*/
const getAutoTheme = (exports.getAutoTheme = () => {
return Services.appinfo.chromeColorSchemeIsDark ? "dark" : "light";
});
/**
* Returns the string value of the current theme,
* like "dark" or "light".
*/
const getTheme = (exports.getTheme = () => {
const theme = Services.prefs.getCharPref(THEME_PREF);
if (theme == "auto") {
return getAutoTheme();
}
return theme;
});
/**
* Returns a color indicated by `type` (like "toolbar-background", or
* "highlight-red"), with the ability to specify a theme, or use whatever the
* current theme is if left unset. If theme not found, falls back to "light"
* theme. Returns null if the type cannot be found for the theme given.
*/
/* eslint-disable no-unused-vars */
const getColor = (exports.getColor = (type, theme) => {
const themeName = theme || getTheme();
let themeFile = getThemeFile(themeName);
let match = themeFile.match(new RegExp("--theme-" + type + ": (.*);"));
const variableMatch = match ? match[1].match(/var\((.*)\)/) : null;
// Check if the match is a color variable and retrieve the value of the color variable
// if needed
if (variableMatch) {
themeFile = getThemeFile("root");
match = themeFile.match(new RegExp(`${variableMatch[1]}: (.*);`));
}
// Return the appropriate variable in the theme, or otherwise, null.
return match ? match[1] : null;
});
/**
* Set the theme preference.
*/
const setTheme = (exports.setTheme = newTheme => {
Services.prefs.setCharPref(THEME_PREF, newTheme);
});
/**
* Add an observer for theme changes.
*/
const addThemeObserver = (exports.addThemeObserver = observer => {
Services.obs.addObserver(observer, "look-and-feel-changed");
Services.prefs.addObserver(THEME_PREF, observer);
});
/**
* Remove an observer for theme changes.
*/
const removeThemeObserver = (exports.removeThemeObserver = observer => {
Services.obs.removeObserver(observer, "look-and-feel-changed");
Services.prefs.removeObserver(THEME_PREF, observer);
});
/* eslint-enable */