System Requirements Document for winter-simple

1. Introduction

The project "winter-simple" aims to build a simple, single-page calculator application for personal use. The calculator will allow users to perform basic arithmetic operations within a clean, uncluttered interface, emphasizing functional clarity and ease of use.

2. System Overview

The winter-simple project delivers a single-page calculator application designed for personal use. The application will allow users to enter calculations, view results, and reset or begin new calculations on the same page. The design is inspired by Dieter Rams' principles of functional clarity and simplicity.

2a. Product Interpretation and Delivery Boundary

The calculator is a single-page application with no user authentication or account management, as it is intended for personal use only. The application will be accessible without any login or identity verification, ensuring ease of access and use. The project scope explicitly excludes advanced or scientific calculator functionalities.

2b. Source Content Inventory

Not applicable as no content source directive was provided.

2c. Page Content and Component Coverage

Calculator

• Display Area

  • Shows the current input and calculation results.
  • Supports displaying up to 10 digits.
  • Error messages for invalid operations (e.g., division by zero).

• Numeric Keypad

  • Buttons for digits 0-9.
  • Decimal point button for floating-point calculations.

• Operation Buttons

  • Basic arithmetic operations: addition, subtraction, multiplication, division.
  • Equals button to compute the result.

• Control Buttons

  • Clear button to reset the current input and result.
  • Backspace button to delete the last entered digit or operation.

• Design Elements

  • Rounded-rectangle buttons with clear labels.
  • Primary orange color for main operation buttons.
  • Green accent for result display.
  • Instant feedback on button press.

3. Functional Requirements

• As a Personal calculator user, I should be able to enter numbers and basic arithmetic operations to perform calculations. (Provenance: explicit)
• As a Personal calculator user, I should be able to view the result of my calculations immediately after pressing the equals button. (Provenance: explicit)
• As a Personal calculator user, I should be able to clear the current input and start a new calculation without refreshing the page. (Provenance: required_inference)
• As a Personal calculator user, I should receive an error message when attempting invalid operations, such as division by zero. (Provenance: required_inference)

4. User Personas

Personal Calculator User

• Context: Uses the calculator for personal arithmetic calculations.
• Primary Goal: To quickly and easily perform basic calculations without distractions.
• Responsibilities: Entering numbers and operations, viewing results, and resetting calculations as needed.
• Interactions: Direct interaction with the calculator interface; no interaction with other users or systems.
• Success: Successfully performs calculations and views results with minimal effort.

5. Core User Flows

1. Performing a Calculation

   • Start: User opens the calculator page.
   • Action: User enters a number, selects an operation, enters another number, and presses the equals button.
   • Result: The result of the calculation is displayed.
   • Next Step: User can either clear the input to start a new calculation or continue with further operations.

2. Clearing Input

   • Start: User has completed a calculation or entered an incorrect input.
   • Action: User presses the clear button.
   • Result: The display area is reset to its initial state.
   • Next Step: User can begin a new calculation.

3. Handling Errors

   • Start: User attempts an invalid operation (e.g., division by zero).
   • Action: User presses the equals button.
   • Result: An error message is displayed.
   • Next Step: User can clear the error message and input to start a new calculation.

6. Visuals Colors and Theme

• Muse: Dieter Rams
• Palette:
  • Background: #F8F8F8
  • Surface: #FFFFFF
  • Text: #000000
  • Primary: #FF9500
  • Accent: #4CAF50
  • Muted: #C0C0C0
• Typography:
  • Headings: Work Sans, Medium weight, small caps
  • Body: Work Sans
  • Scale: 1.25 modular (24/18/16)
• Shape Language: Rounded-rectangle controls
• Layout: Strict grid system
• Motion: Instant, mechanical feedback

7. Signature Design Concept

The calculator's interface will feature a full-screen grid layout with rounded-rectangle buttons. The central display area will feature clear, bold text. The primary orange color will be used for main operation buttons, while a green accent will highlight the result display. The design will ensure instant feedback on button press, maintaining functional clarity and simplicity.

8. Interaction Model & Motion Direction

• Interaction Model: Static
• Motion Tempo: Restrained
• Hero Dimensionality: Flat
• Landing Hero Motion Brief: The calculator interface will provide instant feedback upon button press, with a composed layout that emphasizes clarity and order. The display area will update immediately to reflect user input and calculation results.

9. Non-Functional Requirements

• The application must load quickly and be responsive to user input.
• The interface should be intuitive and easy to use, with no unnecessary elements.
• The application should function correctly across modern web browsers.

10. Tech Stack

• Frontend: React
• Styling: CSS with modular grid layout
• Build Tool: Webpack
• Deployment: Static site hosting (e.g., Netlify or Vercel)

11. Assumptions and Constraints

• The calculator is intended for personal use only and does not require user authentication.
• The application will not support advanced or scientific calculator functions.
• The design will adhere to the principles of functional clarity as inspired by Dieter Rams.

12. Glossary

• Personal Calculator User: An individual using the calculator for personal arithmetic calculations.
• Operation Buttons: Buttons that perform arithmetic operations such as addition, subtraction, multiplication, and division.
• Display Area: The section of the calculator interface that shows the current input and results.