Passing custom props to each styled component through Provider - reactjs

Question

I would like to pass a custom prop (exactly: theme name as string) to each passed styled component through Provider, so it was available throughout the css definition.
ThemeProvider almost does it, but it expects object, not the string. I do not want to pass whole object with theme settings, just the name of my theme.
I do not want to use special theme prop or similar, because then I would have to it manually every single time I create new styled component. Provider seems like the best option if only it cooperated with string.
Is there any possibility to pass a string through Provider to Consumer builded in styled components?
EDIT:
[PARTIAL SOLUTION]
I found what I was looking for when I realized styled-components exports their inner context. That was it. Having access to pure react context gives you original Provider, without any 'only objects' restriction ('only objects' is a styled-components custom provider restriction).
Now I can push to each styled component exactly what I want and if I want.
import styled, { ThemeContext } from 'styled-components';
const StyledComponent = styled.div`
color: ${props => props.theme == 'dark' ? 'white' : 'black'};
`;
const Component = props => {
const theme = 'dark';
return (
<ThemeContext.Provider value={theme}>
<NextLevelComponent>
<StyledComponent />
</NextLevelComponent>
</ThemeContext.Provider>
);
};

Answer 1

Hope I have this correct, from what I've been able to glean. I haven't tried this out but it seems it might work for you. This is lifted directly from the reactjs.org docs regarding context. It passed the string name of the theme down.
const ThemeContext = React.createContext('green');
class App extends React.Component {
render() {
return (
<ThemeContext.Provider value="blue">
<SomeComponent />
</ThemeContext.Provider>
);
}
}
function SomeComponent(props) {
return (
<div>
<OtherComponent />
</div>
);
}
class OtherComponent extends React.Component {
static contextType = ThemeContext;
render() {
return <ThirdComponent theme={this.context} />
}
}

Answer 2

I hope this helps you understand the idea behind ThemeContext from styled-components. I've passed string "blue" to ThemeContext just to show, that it should not be object and you can use just string.
import React, { useContext } from "react";
import ReactDOM from "react-dom";
import styled, { ThemeContext } from "styled-components";
// Define styled button
const Button = styled.button`
font-size: 1em;
margin: 1em;
padding: 0.25em 1em;
border-radius: 3px;
color: ${props => props.theme};
border: 2px solid ${props => props.theme};
`;
// Define the name of the theme / color (string)
const themeName = "blue";
const ThemedButton = () => {
// Get the name from context
const themeName = useContext(ThemeContext);
return <Button theme={themeName}>Themed color: {themeName}</Button>;
};
function App() {
return (
<div className="App">
<ThemeContext.Provider value={themeName}>
<ThemedButton />
</ThemeContext.Provider>
</div>
);
}
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);
Demo: https://codesandbox.io/s/styled-components-example-with-themecontext-cso55