"use client";

import React, { createContext, useState, useContext, useEffect } from 'react';

type Theme = 'light' | 'dark';

interface ThemeContextType {
  theme: Theme;
  toggleTheme: () => void;
}

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

export const ThemeProvider = ({ children }: { children: React.ReactNode }) => {
  const [theme, setTheme] = useState<Theme>('dark');

  // Initialize theme from localStorage if available (client-side only)
  useEffect(() => {
    const storedTheme = localStorage.getItem('theme') as Theme | null;
    if (storedTheme) {
      setTheme(storedTheme);
    } else if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
      setTheme('dark');
    }
  }, []);

  // Update document when theme changes
  useEffect(() => {
    localStorage.setItem('theme', theme);
    document.documentElement.setAttribute('data-theme', theme);
    
    if (theme === 'dark') {
      document.documentElement.classList.add('dark');
    } else {
      document.documentElement.classList.remove('dark');
    }
  }, [theme]);

  const toggleTheme = () => {
    setTheme(prevTheme => prevTheme === 'light' ? 'dark' : 'light');
  };

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

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

export default ThemeContext;