frontend/components/COMPONENTS.md

Components Documentation

Whenever you create a new component in the components/ directory, automatically append a new section following the template below.

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CartProduct

File: components/CartProduct.tsx Description: Product card component. Displays product image, name, description, formatted price, and a Buy button. Width is controlled by the parent grid (w-full), not the card itself.

Props

Prop	Type	Required	Default	Description
image	string	yes	-	URL/path to product image (Next.js Image)
imageAlt	string	no	Anh san pham	Alt text for accessibility
productName	string	yes	-	Product display name
price	number or string	yes	-	If number: auto-formatted to VND. If string: rendered as-is
description	string	yes	-	Short description, clamped to 2 lines
onBuy	() => void	no	undefined	Callback when Buy button is clicked

Internal Logic

• formattedPrice: number -> toLocaleString(vi-VN, { style: currency, currency: VND })
• Image fallback: fa-solid fa-mug-hot icon shown behind image; if image fails onError hides the img element

Styling (CSS variables)

Element	Key classes
Card wrapper	flex flex-col w-full rounded-2xl, shadow uses --color-shadow-sm/md
Image area	relative w-full h-36, bg --color-border-light
Product name	font-bold text-sm, color --color-text-primary, line-clamp-1
Description	text-xs, color --color-text-muted, line-clamp-2
Price	text-sm font-bold, color --color-primary
Buy button	bg --color-primary, hover --color-primary-dark, active:scale-95

Dependencies

• next/image
• Tailwind CSS + CSS custom properties from globals.css
• FontAwesome (fa-solid fa-mug-hot fallback, fa-cart-plus button icon)

Notes

• Card width is w-full - controlled by parent grid in page.tsx
• available field on Product is checked in page.tsx before rendering
• onBuy currently logs to console - TODO: implement cart logic

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Navbar

File: components/Navbar.tsx Description: Left sidebar with collapsible category filter. Sticky below header, full viewport height minus header.

Props

Prop	Type	Required	Default	Description
isOpen	boolean	yes	-	true = expanded (240px), false = collapsed (64px)
onToggle	() => void	yes	-	Toggle expand/collapse
activeCategory	string	no	all	Currently selected category id
onCategoryChange	(id: string) => void	no	undefined	Fired when user clicks a category

Behavior

• Collapsed: 64px wide, icon only (w-16)
• Expanded: 240px wide, icon + label (w-60)
• Width transition: transition-all duration-250ms
• Active category: highlighted with --color-primary background
• Footer shows SHOP_INFO.openHours (icon only when collapsed)

Styling

Element	Key classes
Aside	sticky, border-r --color-border, bg --color-bg-sidebar
Toggle button	w-8 h-8 rounded-lg, hover bg --color-border-light
Active item	bg --color-primary text-white shadow-sm
Inactive item	hover bg --color-border-light, color --color-text-secondary

Dependencies

• next/link
• lib/constants: MENU_CATEGORIES, SHOP_INFO
• lib/types: MenuCategory
• FontAwesome icons

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Header (layouts/header.tsx)

File: layouts/header.tsx Description: Sticky top bar. 2-column layout: Brand (left) + Auth button (right). Auth cycles Guest -> Manager -> Staff -> Guest for UI demo.

Props

None - reads SHOP_INFO and MOCK_USERS from lib/constants directly.

Internal State

State	Type	Description
user	User or null	Current demo user. null = guest

Auth States

State	Appearance
Guest (null)	Brown primary button, Dang nhap label
Manager	Gold/caramel badge with user-tie icon
Staff	Avatar circle + name, bordered button

Responsive

• Logo + shop name: always visible
• Tagline: hidden < md, shown md+
• Button label: hidden < sm, shown sm+

Dependencies

• next/image, next/link
• lib/constants: SHOP_INFO, MOCK_USERS
• lib/types: User
• FontAwesome icons

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Footer (layouts/footer.tsx)

File: layouts/footer.tsx Description: Site footer with 12-column grid. 3 sections: Brand info, Social links, WiFi card.

Props

None - reads SHOP_INFO and SOCIAL_LINKS from lib/constants directly.

Layout

Section	Mobile	md	lg/xl
Brand info	col-span-12	col-span-6	col-span-8/6
Social + WiFi	col-span-12	col-span-6	col-span-4/6

Sections

1. Brand: logo, name, tagline, address, phone, email, open hours
2. Social: Facebook, TikTok, Website links
3. WiFi: network name + password in monospace styled box
4. Bottom bar: copyright + Made with heart in Vietnam

Dependencies

• next/image, next/link
• lib/constants: SHOP_INFO, SOCIAL_LINKS
• FontAwesome icons

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CartFab

File: components/CartFab.tsx Description: Floating Action Button displaying cart item count. Shows badge with number of items and total price on hover.

Props

Prop	Type	Required	Default	Description
onClick	() => void	no	undefined	Callback when FAB is clicked

Features

• Displays cart icon with item count badge
• Shows total price on hover in tooltip
• Sticky position (bottom-right)
• Uses cart context to get items and total

Styling

Element	Key classes
FAB button	fixed bottom-6 right-6, rounded-full, shadow-lg
Badge	absolute top-0 right-0, red bg, small font
Tooltip	appears on hover, shows total price

Dependencies

• lib/cart-context: useCart()
• FontAwesome icons

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Contexts Documentation

AuthContext (lib/auth-context.tsx)

File: lib/auth-context.tsx Description: Manages user authentication state including login, logout, and registration. Uses localStorage for persistence.

Provider Props

Prop	Type	Required	Description
children	React.ReactNode	yes	Child components

Hook: useAuth()

Returns AuthContextType with:

Property	Type	Description
user	User | null	Current logged-in user or null
login	(username: string, password: string) => boolean	Login function; returns success status
logout	() => void	Logout function; clears user and localStorage
registerPhone	string | null	Phone number during registration flow
setRegisterPhone	(phone: string | null) => void	Update registerPhone state
completeRegistration	(phone: string) => void	Complete registration and create customer account

Mock Database

Pre-configured accounts:

• Manager: admin / admin
• Staff: Nguyễn Văn An / Nguyễn Văn An, Trần Thị Bình / Trần Thị Bình, etc.
• Customer: Phone number as username, user1 as password

Storage

• Key: coffee-shop-user
• Format: JSON serialized User object

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CartContext (lib/cart-context.tsx)

File: lib/cart-context.tsx Description: Manages shopping cart state with localStorage persistence. Tracks items, quantities, and totals.

Provider Props

Prop	Type	Required	Description
children	React.ReactNode	yes	Child components

Hook: useCart()

Returns CartContextValue with:

Property	Type	Description
items	CartItem[]	Array of items in cart
totalItems	number	Total quantity of items
totalPrice	number	Total price in VND
addToCart	(product: Product) => void	Add or increase product quantity
increaseQty	(id: number) => void	Increase product quantity by 1
decreaseQty	(id: number) => void	Decrease product quantity by 1 (removes if qty reaches 0)
removeFromCart	(id: number) => void	Remove product from cart
setQuantity	(id: number, quantity: number) => void	Set exact quantity (removes if 0)

CartItem Interface

interface CartItem {
  id: number;
  name: string;
  description: string;
  price: number;
  quantity: number;
}

Storage

• Key: coffee-shop-cart
• Format: JSON serialized CartItem[]
• Auto-loads on mount and auto-saves on change

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MenuContext (lib/menu-context.tsx)

File: lib/menu-context.tsx Description: Provides shared category/menu state across components. Synchronizes Header mobile menu and Navbar sidebar selection.

Provider Props

Prop	Type	Required	Description
children	React.ReactNode	yes	Child components

Hook: useMenu()

Returns MenuContextType with:

Property	Type	Description
activeCategory	string	Currently selected category id (default: "all")
setActiveCategory	(id: string) => void	Update active category

Use Cases

• Sync Navbar sidebar and Header mobile menu category selection
• Clear search query when category changes (implemented in main page)
• Pass selected category to product filter logic

Default Value

• activeCategory: "all" - Show all products by default