Implement shopping cart and checkout flow

[Copilot]

Adds complete cart and checkout functionality to the e-commerce application.

Implementation

State Management

• CartContext provides global cart state via React Context API
• Handles add/remove/update/clear operations with discount price calculations
• Exposes getTotalItems() and getTotalPrice() helpers

Cart Page (/cart)

• Displays items with quantity controls and remove buttons
• Order summary with subtotal, tax (8%), shipping (free), and total
• Empty state redirects to products

Checkout Page (/checkout)

• Two-column layout: billing/payment form + order summary
• Success modal with 3s auto-redirect to products
• Clears cart on order placement
• useEffect cleanup prevents memory leaks from unmounted timeout

Navigation Integration

• Cart icon with badge showing live item count
• Updates reactively via getTotalItems()

Shared Constants (constants.ts)

export const TAX_RATE = 0.08;
export const SHIPPING_COST = 0;
export const ORDER_SUCCESS_REDIRECT_DELAY = 3000;

Notes

• Payment fields are demo-only with inline security warnings
• All components support dark/light mode theming
• Routes added: /cart, /checkout

Screenshots

Cart Page

Checkout Page

Cart Icon with Badge

Original prompt

implement a checkout feature

[Chronological Review: The conversation began with a user request to explain a project, followed by a request to analyze the codebase for generating or updating `.github/copilot-instructions.md`. The user then requested the implementation of a simple cart icon and cart page, followed by a request to commit changes into a `cart-demo` branch and generate a pull request. Finally, the user requested the implementation of a checkout feature.] [Intent Mapping: 1. "explain this project" - User seeks an overview of the project. 2. "Analyze this codebase to generate or update `.github/copilot-instructions.md`" - User wants to create documentation for AI coding agents to understand the codebase. 3. "implement the simple cart icon and cart page that displays the items in the cart" - User requests a specific UI feature. 4. "please commit these changes into a cart-demo branch and generate a pull request" - User wants to save and share the changes made. 5. "implement a checkout feature" - User requests another specific feature related to the cart functionality.] [Technical Inventory: - Tools: GitHub Copilot for code suggestions and documentation generation. - Files: `.github/copilot-instructions.md` for AI guidance, cart-related components for UI implementation. - Concepts: Git branching for version control, pull requests for code review and collaboration.] [Code Archaeology: - No specific files or code changes were detailed in the conversation, but the focus was on implementing UI components and documentation for AI agents.] [Progress Assessment: - Completed Tasks: None explicitly confirmed as completed. - Partially Complete Work: Cart icon and cart page implementation in progress, changes to be committed to a new branch, checkout feature requested.] [Context Validation: All user requests and intents are captured, focusing on UI implementation and documentation for AI agents.] [Recent Commands Analysis: - Last Agent Commands: User requested to "commit these changes into a cart-demo branch and generate a pull request" and "implement a checkout feature." - Tool Results Summary: No specific tool results were provided, but the commands indicate ongoing development work. - Pre-Summary State: The agent was actively working on implementing the checkout feature when the token budget was exceeded. - Operation Context: These commands relate to the user's goal of enhancing the cart functionality and ensuring proper version control through Git.]

1. Conversation Overview: - Primary Objectives: 1. "explain this project" - Overview of the project. 2. "Analyze this codebase to generate or update `.github/copilot-instructions.md`" - Documentation for AI agents. 3. "implement the simple cart icon and cart page that displays the items in the cart" - Specific UI feature request. 4. "please commit these changes into a cart-demo branch and generate a pull request" - Save and share changes. 5. "implement a checkout feature" - Additional functionality request. - Session Context: The conversation has focused on understanding the project, enhancing cart functionality, and ensuring proper documentation for AI agents. - User Intent Evolution: The user has moved from seeking project understanding to specific feature implementations and version control actions.

2. Technical Foundation:

• GitHub Copilot: Used for generating code and documentation.
• .github/copilot-instructions.md: Target file for AI guidance documentation.
• Cart-related components: Focus of recent UI implementation requests.

3. Codebase Status:

• [File Name 1]: Not specified, but related to cart functionality.
• Purpose: Enhance user experience with cart features.
• Current State: Implementation of cart icon and page in progress.
• Key Code Segments: Not detailed in conversation.
• Dependencies: Related to overall project architecture and UI components.

4. Problem Resolution:

• Issues Encountered: No specific technical problems were mentioned.
• Solutions Implemented: Ongoing implementation of requested features.
• Debugging Context: Not applicable at this stage.
• Lessons Learned: Not applicable at this stage.

5. Progress Tracking:

• Completed Tasks: None confirmed.
• Partially Complete Work: Cart icon and page implementation, checkout feature requested.
• Validated Outcomes: None confirmed.

6. Active Work State:

• Current Focus: Implementing the checkout feature.
• Recent Context: User requested to commit changes and generate a pull request, indicating ongoing development.
• Working Code: Not specified, but related to cart functionality.
• Immediate Context: User was focused on enhancing cart features.

7. Recent Operations:

• Last Agent Commands:
  1. "please commit these changes into a cart-demo branch and generate a pull request"
  2. "implement a checkout feature"
• Tool Results Summary: No specific results provided, indicating ongoing work.
• Pre-Summary State: The agent was actively w...

Created from VS Code.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.