import React, { createContext, useContext } from 'react';
import { useUIStore } from '../stores/ui.store';

interface ThemeContextType {
  theme: 'light' | 'dark' | 'auto';
  setTheme: (theme: 'light' | 'dark' | 'auto') => void;
  resolvedTheme: 'light' | 'dark';
}

const ThemeContext = createContext<ThemeContextType | undefined>(undefined);

export const useTheme = () => {
  const context = useContext(ThemeContext);
  if (context === undefined) {
    throw new Error('useTheme must be used within a ThemeProvider');
  }
  return context;
};

interface ThemeProviderProps {
  children: React.ReactNode;
}

export const ThemeProvider: React.FC<ThemeProviderProps> = ({ children }) => {
  const { theme, setTheme } = useUIStore();
  
  // Calculate resolved theme based on current theme and system preference
  const getResolvedTheme = (): 'light' | 'dark' => {
    if (theme === 'auto') {
      return window.matchMedia('(prefers-color-scheme: dark)').matches ? 'dark' : 'light';
    }
    return theme as 'light' | 'dark';
  };

  const contextValue: ThemeContextType = {
    theme,
    setTheme,
    resolvedTheme: getResolvedTheme(),
  };

  return (
    <ThemeContext.Provider value={contextValue}>
      {children}
    </ThemeContext.Provider>
  );
};