import AsyncStorage from '@react-native-async-storage/async-storage';
import React, { createContext, ReactNode, useContext, useEffect, useState } from 'react';
import { useColorScheme } from 'react-native';
import { Colors } from '@/constants/Colors';

type Theme = 'light' | 'dark' | 'system';
type StartTheme = 'light' | 'dark';

interface ThemeContextType {
   theme: Theme;
   activeTheme: StartTheme;
   setTheme: (theme: Theme) => void;
   colors: typeof Colors.light;
}

const ThemeContext = createContext<ThemeContextType>({
   theme: 'system',
   activeTheme: 'light',
   setTheme: () => { },
   colors: Colors.light,
});

export const useTheme = () => useContext(ThemeContext);

export default function ThemeProvider({ children }: { children: ReactNode }) {
   const systemColorScheme = useColorScheme();
   const [theme, setThemeState] = useState<Theme>('system');
   const [isReady, setIsReady] = useState(false);

   useEffect(() => {
      (async () => {
         try {
            const storedTheme = await AsyncStorage.getItem('@theme');
            if (storedTheme) {
               setThemeState(storedTheme as Theme);
            }
         } catch (e) {
            console.error('Failed to load theme', e);
         } finally {
            setIsReady(true);
         }
      })();
   }, []);

   const setTheme = async (newTheme: Theme) => {
      setThemeState(newTheme);
      try {
         await AsyncStorage.setItem('@theme', newTheme);
      } catch (e) {
         console.error('Failed to save theme', e);
      }
   };

   if (!isReady) {
      return null;
   }

   const activeTheme = theme === 'system' ? (systemColorScheme || 'light') : theme;
   const colors = Colors[activeTheme];

   return (
      <ThemeContext.Provider value={{ theme, activeTheme, setTheme, colors }}>
         {children}
      </ThemeContext.Provider>
   );
}