budibase/packages/builder/src/builderStore/generate_css.js

export const generate_screen_css = (component_arr) => {
	let styles = '';
	for (const { _styles, _id, _children, _component } of component_arr) {
		let [ componentName ] = _component.match(/[a-z]*$/);
		Object.keys(_styles).forEach((selector) => {
			const cssString = generate_css(_styles[selector]);
			if (cssString) {
				styles += apply_class(_id, componentName, cssString, selector);
			}
		});
		if (_children && _children.length) {
			styles += generate_screen_css(_children) + '\n';
		}
	}
	return styles.trim();
};

export const generate_css = (style) => {
	let cssString = Object.entries(style).reduce((str, [ key, value ]) => {
		//TODO Handle arrays and objects here also
		if (typeof value === 'string') {
			if (value) {
				return (str += `${key}: ${value};\n`);
			}
		} else if (Array.isArray(value)) {
			if (value.length > 0 && !value.every((v) => v === '')) {
				return (str += `${key}: ${value.join(' ')};\n`);
			}
		}
	}, '');

	return (cssString || '').trim();
};

export const apply_class = (id, name = 'element', styles, selector) => {
	if (selector === 'normal') {
		return `.${name}-${id} {\n${styles}\n}`;
	} else {
		let sel = selector === 'selected' ? '::selection' : `:${selector}`;
		return `.${name}-${id}${sel} {\n${styles}\n}`;
	}
};