# Product Requirements Document: Todo Task Submission System

## 1. Overview

The Todo Task Submission System is a modern single-page web application that allows users to submit their name and email through a simple form. Upon submission, the data is persisted and displayed in a table below the form, providing immediate visual feedback of all submitted entries. This lightweight application serves as a data collection and display tool without requiring user authentication or complex UI design.

## 2. User Roles

### Anonymous User (Default Role)
- Can access the single-page application without authentication
- Can fill out and submit the form with name and email
- Can view all previously submitted entries in the table
- Can interact with all features without login or registration

## 3. Core Entities

### Submission
The primary data entity representing a single form submission.

**Attributes:**
- `id` (UUID/Integer) - Unique identifier for the submission
- `name` (String) - The name provided by the user
- `email` (String) - The email address provided by the user
- `createdAt` (Timestamp) - Date and time when the submission was created
- `updatedAt` (Timestamp) - Date and time when the submission was last modified

## 4. Entity Relationships

### Submission Entity
- **Standalone entity** - No relationships to other entities
- Each submission is independent and self-contained
- No foreign key relationships required
- No hierarchical or associative relationships

## 5. Key Workflows

### Workflow 1: Page Load
1. User navigates to the application URL (https://freemeal.dev.dalfin.ai)
2. System loads the single-page application
3. System displays the submission form (empty state)
4. System fetches all existing submissions from the database
5. System renders submissions in a table below the form
6. Application is ready for user interaction

### Workflow 2: Form Submission
1. User enters their name in the Name field
2. User enters their email in the Email field
3. User clicks the Submit button
4. System validates the form inputs (client-side)
5. System sends submission data to the backend API
6. Backend validates the data (server-side)
7. Backend creates a new Submission record in the database
8. Backend returns success response with the created submission
9. Frontend adds the new submission to the table
10. Frontend clears the form fields
11. User sees the new entry appear in the table immediately

### Workflow 3: Data Retrieval and Display
1. System queries the database for all Submission records
2. System orders submissions by creation date (newest first or oldest first)
3. System returns the list of submissions to the frontend
4. Frontend renders each submission as a row in the table
5. Table displays all relevant fields (name, email, timestamp)

## 6. Features & Requirements

### 6.1 Form Module

#### FR-1.1: Name Input Field
- Display a text input field labeled "Name"
- Accept alphanumeric characters and common name characters (spaces, hyphens, apostrophes)
- Maximum length: 100 characters
- Field is required

#### FR-1.2: Email Input Field
- Display an email input field labeled "Email"
- Accept valid email format (user@domain.tld)
- Maximum length: 255 characters
- Field is required

#### FR-1.3: Submit Button
- Display a button labeled "Submit"
- Button is enabled when form is not submitting
- Button shows loading state during submission
- Button triggers form validation and submission on click

#### FR-1.4: Form Validation
- Validate that Name field is not empty
- Validate that Email field is not empty
- Validate that Email field contains a valid email format
- Display inline error messages for invalid fields
- Prevent submission if validation fails

#### FR-1.5: Form Reset
- Clear all form fields after successful submission
- Reset validation states after successful submission
- Return focus to the Name field after submission

### 6.2 Data Display Module

#### FR-2.1: Submissions Table
- Display a table with columns: ID, Name, Email, Created At
- Render all submitted entries as table rows
- Show most recent submissions first (descending order by createdAt)
- Display empty state message when no submissions exist
- Auto-update table when new submission is added

#### FR-2.2: Table Columns
- **ID Column**: Display the unique identifier for each submission
- **Name Column**: Display the submitted name
- **Email Column**: Display the submitted email address
- **Created At Column**: Display the submission timestamp in readable format (e.g., "YYYY-MM-DD HH:MM:SS")

#### FR-2.3: Data Refresh
- Automatically add new submissions to the table without page reload
- Maintain table state during form interactions
- No manual refresh button required

### 6.3 API Module

#### FR-3.1: Create Submission Endpoint
- **Method**: POST
- **Path**: `/api/submissions`
- **Request Body**: `{ "name": "string", "email": "string" }`
- **Response**: `{ "id": "uuid", "name": "string", "email": "string", "createdAt": "timestamp", "updatedAt": "timestamp" }`
- **Status Codes**: 201 (Created), 400 (Bad Request), 500 (Server Error)

#### FR-3.2: List Submissions Endpoint
- **Method**: GET
- **Path**: `/api/submissions`
- **Query Parameters**: None required (optional: `limit`, `offset` for pagination)
- **Response**: `{ "submissions": [ {...}, {...} ] }`
- **Status Codes**: 200 (OK), 500 (Server Error)

### 6.4 User Interface Module

#### FR-4.1: Single Page Layout
- Display form at the top of the page
- Display submissions table below the form
- Responsive layout that works on desktop and mobile devices
- No navigation or multiple pages required

#### FR-4.2: Visual Feedback
- Show loading indicator during form submission
- Display success message after successful submission (optional)
- Display error message if submission fails
- Highlight validation errors on form fields

## 7. Business Rules

### BR-1: Data Validation Rules
- **BR-1.1**: Name field must not be empty or contain only whitespace
- **BR-1.2**: Name field must be between 1 and 100 characters
- **BR-1.3**: Email field must not be empty
- **BR-1.4**: Email field must match standard email regex pattern: `^[^\s@]+@[^\s@]+\.[^\s@]+$`
- **BR-1.5**: Email field must be between 5 and 255 characters

### BR-2: Data Storage Rules
- **BR-2.1**: Each submission must have a unique identifier (auto-generated)
- **BR-2.2**: CreatedAt timestamp is automatically set on record creation
- **BR-2.3**: UpdatedAt timestamp is automatically updated on record modification
- **BR-2.4**: All submissions are permanently stored (no automatic deletion)
- **BR-2.5**: Duplicate submissions (same name and email) are allowed

### BR-3: Data Display Rules
- **BR-3.1**: Submissions are displayed in reverse chronological order (newest first)
- **BR-3.2**: All submissions are visible to all users (no privacy filtering)
- **BR-3.3**: Table displays all submissions without pagination (or with default pagination if count exceeds reasonable limit)

### BR-4: Form Behavior Rules
- **BR-4.1**: Form submission is only allowed when all validations pass
- **BR-4.2**: Form fields are cleared only after successful submission
- **BR-4.3**: Multiple rapid submissions are allowed (no rate limiting required)
- **BR-4.4**: Form remains accessible during and after submission

## 8. Non-Functional Requirements

### NFR-1: Performance
- **NFR-1.1**: Page load time must be under 2 seconds on standard broadband connection
- **NFR-1.2**: Form submission response time must be under 500ms under normal load
- **NFR-1.3**: Table rendering must handle up to 1,000 submissions without significant lag
- **NFR-1.4**: API endpoints must respond within 200ms for 95th percentile requests

### NFR-2: Security
- **NFR-2.1**: Implement CSRF protection for form submissions
- **NFR-2.2**: Sanitize all user inputs to prevent XSS attacks
- **NFR-2.3**: Validate all inputs on both client and server side
- **NFR-2.4**: Use HTTPS for all communications (enforced by domain)
- **NFR-2.5**: Implement rate limiting to prevent abuse (e.g., 100 requests per IP per minute)
- **NFR-2.6**: Protect against SQL injection through parameterized queries or ORM

### NFR-3: Scalability
- **NFR-3.1**: Database must support at least 100,000 submission records
- **NFR-3.2**: System must handle at least 100 concurrent users
- **NFR-3.3**: API must support horizontal scaling if needed
- **NFR-3.4**: Consider pagination for table display if submissions exceed 1,000 records

### NFR-4: Reliability
- **NFR-4.1**: System uptime must be 99.5% or higher
- **NFR-4.2**: Failed submissions must display clear error messages to users
- **NFR-4.3**: Database transactions must be atomic (all-or-nothing)
- **NFR-4.4**: Implement proper error logging for debugging

### NFR-5: Usability
- **NFR-5.1**: Form must be keyboard accessible (tab navigation, enter to submit)
- **NFR-5.2**: Error messages must be clear and actionable
- **NFR-5.3**: Application must work on modern browsers (Chrome, Firefox, Safari, Edge - latest 2 versions)
- **NFR-5.4**: Mobile responsive design (works on screens 320px width and above)

### NFR-6: Maintainability
- **NFR-6.1**: Code must follow consistent style guidelines
- **NFR-6.2**: API must be RESTful and well-documented
- **NFR-6.3**: Database schema must be version-controlled with migrations
- **NFR-6.4**: Environment-specific configurations must be externalized

### NFR-7: Compatibility
- **NFR-7.1**: Frontend must work without JavaScript frameworks (or with modern frameworks like React, Vue, or Svelte)
- **NFR-7.2**: Backend must be framework-agnostic (can be implemented in Node.js, Python, Ruby, etc.)
- **NFR-7.3**: Database can be SQL (PostgreSQL, MySQL) or NoSQL (MongoDB)
- **NFR-7.4**: API must return JSON responses

### NFR-8: Deployment
- **NFR-8.1**: Application must be deployable to the specified domain (https://freemeal.dev.dalfin.ai)
- **NFR-8.2**: Database connection strings and secrets must be environment variables
- **NFR-8.3**: Application must support containerization (Docker) for easy deployment
- **NFR-8.4**: Static assets must be served efficiently (CDN or optimized server configuration)

---

## Appendix: Technical Considerations

### Recommended Technology Stack Options

**Frontend:**
- HTML5, CSS3, JavaScript (Vanilla or Framework)
- React, Vue.js, or Svelte for component-based architecture
- Axios or Fetch API for HTTP requests

**Backend:**
- Node.js with Express
- Python with Flask/FastAPI
- Ruby on Rails
- Any framework supporting RESTful APIs

**Database:**
- PostgreSQL (recommended for relational data)
- MySQL
- MongoDB (if NoSQL preferred)

**Hosting:**
- Domain already specified: https://freemeal.dev.dalfin.ai
- Backend and frontend can be deployed together or separately

### API Contract Example

```
POST /api/submissions
Content-Type: application/json

Request:
{
  "name": "John Doe",
  "email": "john.doe@example.com"
}

Response (201 Created):
{
  "id": "123e4567-e89b-12d3-a456-426614174000",
  "name": "John Doe",
  "email": "john.doe@example.com",
  "createdAt": "2025-01-20T10:30:00Z",
  "updatedAt": "2025-01-20T10:30:00Z"
}

---

GET /api/submissions

Response (200 OK):
{
  "submissions": [
    {
      "id": "123e4567-e89b-12d3-a456-426614174000",
      "name": "John Doe",
      "email": "john.doe@example.com",
      "createdAt": "2025-01-20T10:30:00Z",
      "updatedAt": "2025-01-20T10:30:00Z"
    }
  ]
}
```

---

**Document Version**: 1.0  
**Last Updated**: 2025-01-20  
**Status**: Ready for Implementation