# DJ Management System

## Overview

This is a full-stack web application for managing DJs, events, and scheduling. The system provides a comprehensive platform for DJ profile management, event scheduling, availability tracking, and administrative oversight. Built with modern web technologies, it features a React frontend with a Node.js/Express backend, utilizing PostgreSQL for data persistence.

## User Preferences

Preferred communication style: Simple, everyday language.

## System Architecture

### Frontend Architecture
- **Framework**: React with TypeScript
- **Build Tool**: Vite for fast development and optimized builds
- **UI Components**: Shadcn/UI components built on Radix UI primitives
- **Styling**: Tailwind CSS with custom design tokens
- **Routing**: Wouter for lightweight client-side routing
- **State Management**: TanStack Query for server state management
- **Form Handling**: React Hook Form with Zod validation

### Backend Architecture
- **Runtime**: Node.js with Express.js framework
- **Language**: TypeScript with ES modules
- **Database**: PostgreSQL with Drizzle ORM
- **Authentication**: Replit Auth with OpenID Connect
- **Session Management**: Express sessions with PostgreSQL storage
- **Database Connection**: Neon serverless PostgreSQL

### Authentication & Authorization
- **Provider**: Replit Auth (OpenID Connect)
- **Session Storage**: PostgreSQL-backed sessions using connect-pg-simple
- **Role-based Access**: Two roles - DJ and Admin
- **Protected Routes**: Authentication middleware for API endpoints
- **User Management**: Admin-initiated invitations with secure registration links

## Key Components

### User Management
- **DJ Users**: Profile management, event creation, availability setting
- **Admin Users**: System oversight, user management, event approval
- **Invitation System**: Secure invitation links for DJ onboarding
- **Profile Features**: Display names, profile images, social media links

### Event Management
- **Event Types**: Configurable event categories (radio, club, special events)
- **Event Creation**: DJs can create personal events, admins manage all events
- **Scheduling**: Date, time, location, and description management
- **Removal Requests**: DJs can request removal from admin-assigned events

### Availability System
- **Calendar Interface**: Visual availability management
- **Date Ranges**: Support for single dates or date ranges
- **Frequency Limits**: Maximum events per month configuration
- **Conflict Prevention**: Automatic checking against existing commitments

### Administrative Tools
- **DJ Management**: Invite, activate/deactivate, role management
- **Event Oversight**: Approve/deny removal requests, manage all events
- **Schedule Templates**: Recurring event templates (e.g., weekly radio shows)
- **Assignment Tool**: Automated DJ assignment with rotation logic

## Data Flow

### User Authentication Flow
1. User accesses protected route
2. Replit Auth middleware validates session
3. User data retrieved from PostgreSQL
4. Role-based access control applied
5. Frontend receives user context

### Event Management Flow
1. DJ creates event through form
2. Client-side validation with Zod schema
3. API request to Express backend
4. Database validation and storage
5. Real-time updates via TanStack Query
6. Admin notifications for approval workflows

### Availability Management Flow
1. DJ selects unavailable dates on calendar
2. Date range validation and conflict checking
3. Database storage with user association
4. Integration with assignment algorithms
5. Real-time calendar updates

## External Dependencies

### Core Dependencies
- **@neondatabase/serverless**: PostgreSQL connection for serverless environments
- **drizzle-orm**: Type-safe database ORM with PostgreSQL dialect
- **@tanstack/react-query**: Server state management and caching
- **@radix-ui/react-***: Accessible UI component primitives
- **react-hook-form**: Form state management and validation
- **zod**: Schema validation for forms and API endpoints

### Development Dependencies
- **vite**: Fast build tool with HMR support
- **typescript**: Static type checking
- **tailwindcss**: Utility-first CSS framework
- **drizzle-kit**: Database migration and introspection tools

### Authentication Dependencies
- **openid-client**: OpenID Connect client implementation
- **passport**: Authentication middleware
- **connect-pg-simple**: PostgreSQL session store
- **express-session**: Session management middleware

## Deployment Strategy

### Build Process
- **Frontend**: Vite builds optimized static assets to `dist/public`
- **Backend**: esbuild bundles server code to `dist/index.js`
- **Database**: Drizzle migrations manage schema changes
- **Environment**: Supports both development and production modes

### Environment Configuration
- **DATABASE_URL**: PostgreSQL connection string (required)
- **SESSION_SECRET**: Session encryption key
- **REPLIT_DOMAINS**: Allowed domains for Replit Auth
- **NODE_ENV**: Environment mode (development/production)

### Hosting Requirements
- **Node.js**: Version 18+ with ES modules support
- **PostgreSQL**: Compatible with Neon serverless or traditional PostgreSQL
- **SSL/TLS**: Required for secure authentication flows
- **File Storage**: Local storage for uploaded profile images (can be extended to cloud storage)

### Database Architecture
- **Schema Management**: Drizzle ORM with TypeScript schema definitions
- **Migrations**: Version-controlled database changes
- **Indexing**: Optimized for query performance on events and availability
- **Relationships**: Proper foreign key constraints and relations
- **Session Storage**: Dedicated table for authentication sessions

The system is designed to be easily deployable on platforms like Replit, Vercel, or traditional hosting environments, with PostgreSQL as the primary database requirement.