Convert all React class components to functional components with hooks

[devin-ai-integration]

Convert all React class components to functional components with hooks

Summary

Modernized the entire React codebase by converting all class components to functional components using React hooks. This includes state management conversion from this.state/this.setState to useState, event handler updates, and lifecycle method conversion (componentDidUpdate → useEffect).

Components converted:

• App.js - Main application state management (cartItems, isCartOpen, searchTerm, currentPage)
• Cart.js - Shopping cart with lifecycle method (componentDidUpdate → useEffect)
• Header.js - Navigation and search functionality
• Footer.js - Newsletter subscription state
• ProductCard.js - Product interaction state
• ProductList.js - Complex sorting/filtering logic and product data
• Page components - Home, Furniture, Jewelry, ArtDecor with product arrays

Key changes:

• Replaced this.state and this.setState() with useState hooks
• Converted class methods to functional component functions
• Replaced componentDidUpdate with useEffect in Cart component
• Maintained all existing prop interfaces and functionality

Review & Testing Checklist for Human

⚠️ HIGH RISK - Comprehensive testing required (5 critical items)

• Test complete cart workflow end-to-end - Add items, update quantities, remove items, verify totals update correctly across navigation
• Verify search and filtering functionality - Test search terms, category filters, and sorting options in ProductList component
• Test navigation between all pages - Ensure state persists correctly when switching between Home, Furniture, Jewelry, Art & Decor pages
• Check cart state synchronization - Verify cart overlay opens/closes properly and cart count updates consistently in header
• Test newsletter subscription - Verify email input, subscription confirmation, and timeout functionality in Footer

Notes

• All components maintain their original prop interfaces to prevent breaking changes
• Basic functionality testing completed locally - cart operations, navigation, and search all working
• ESLint passes with no warnings or errors
• This refactoring touches every component in the application, requiring thorough end-to-end testing

Requested by: @rohan-ramani
Link to Devin run: https://app.devin.ai/sessions/9cf96380b8d94979b734054d1f9c2fdb

[devin-ai-integration]

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