System Requirements Document for marine-small

1. Introduction

The Mini Expense Tracker is a small, full-stack web application designed to help users record and manage their daily expenses. The application focuses on providing a clean, modern, and responsive interface that allows users to track their expenses efficiently without unnecessary features. The target audience is individuals looking for a straightforward tool to manage personal expenses.

2. System Overview

The Mini Expense Tracker is a locally runnable application that includes a responsive frontend, a RESTful backend API, and a lightweight SQLite database. The application allows users to add, edit, delete, and view expenses, with a dashboard summarizing total expenses, transaction count, and the highest expense. The system is designed to be simple, organized, and easy to use, with a focus on functionality and error handling.

2a. Product Interpretation and Delivery Boundary

The application is delivered as a complete package that can be run locally. It includes a frontend built with a modern, responsive design, a backend API for data management, and a SQLite database for persistence. The application does not include advanced features such as authentication or cloud services, adhering to the project's scope of being a simple and understandable expense tracker.

2b. Source Content Inventory

Not applicable as no content_source directive was provided.

2c. Page Content and Component Coverage

Landing

• Purpose: Introduce the Mini Expense Tracker and its core functionalities.
• Components:
  • Introduction to the application and its use.
  • Overview of features such as expense recording and management.

Dashboard

• Purpose: Display key metrics and list of expenses.
• Components:
  • Total expenses, number of transactions, highest expense.
  • List of all recorded expenses with title, amount, category, date, and optional note.
  • "Add Expense" button to open the form.
  • Edit and Delete actions for each expense.
  • Category filter and summary of expenses by category.
  • Loading, empty-state, and error-state messages.

Add Expense

• Purpose: Allow users to add new expenses.
• Components:
  • Form fields for title, amount, category, date, and optional note.
  • Validation messages for required fields.
  • Submit button to save the expense.

Edit Expense

• Purpose: Enable users to edit existing expenses.
• Components:
  • Pre-filled form with existing expense details.
  • Editable fields for title, amount, category, date, and note.
  • Save changes button to update the expense.

3. Functional Requirements

• As an Expense manager, I should be able to view a dashboard displaying total expenses, number of transactions, and highest expense. (explicit)
• As an Expense manager, I should be able to see a list of all recorded expenses with details such as title, amount, category, date, and optional note. (explicit)
• As an Expense manager, I should be able to add a new expense with a title, amount, category, date, and optional note. (explicit)
• As an Expense manager, I should be able to edit an existing expense to update its details. (explicit)
• As an Expense manager, I should be able to delete an expense. (explicit)
• As an Expense manager, I should be able to filter expenses by category and view a summary of expenses by category. (explicit)
• As an Expense manager, I should see appropriate loading, empty-state, and error-state messages. (explicit)
• As an Expense manager, I should be able to interact with the backend API to manage expenses. (required_inference)
• As an Expense manager, I should see API validation and error responses surfaced by the interface. (required_inference)

4. User Personas

• Expense manager: The user who records, views, filters, edits, and deletes their daily expenses and reviews dashboard summaries.

5. Core User Flows

1. Viewing Dashboard:

   • The Expense manager accesses the Dashboard page.
   • The system displays total expenses, number of transactions, and highest expense.
   • The system lists all recorded expenses with relevant details.

2. Adding an Expense:

   • The Expense manager clicks the "Add Expense" button on the Dashboard.
   • The system navigates to the Add Expense page.
   • The Expense manager fills in the expense details and submits the form.
   • The system validates the input and saves the expense to the database.
   • The system updates the Dashboard with the new expense.

3. Editing an Expense:

   • The Expense manager selects an expense to edit from the Dashboard.
   • The system navigates to the Edit Expense page with pre-filled details.
   • The Expense manager updates the details and saves changes.
   • The system validates the input and updates the expense in the database.
   • The system reflects the changes on the Dashboard.

4. Deleting an Expense:

   • The Expense manager selects an expense to delete from the Dashboard.
   • The system prompts for confirmation.
   • Upon confirmation, the system deletes the expense from the database.
   • The system updates the Dashboard to remove the deleted expense.

5. Filtering Expenses by Category:

   • The Expense manager selects a category filter on the Dashboard.
   • The system displays expenses only from the selected category.
   • The system updates the category summary accordingly.

6. Visuals Colors and Theme

• Muse: Erik Spiekermann
• Palette:
  • Background: #F6F3EE
  • Surface: #FFFFFF
  • Text: #333333
  • Primary: #E63946
  • Accent: #457B9D
  • Muted: #A8DADC
• Typography:
  • Headings: Fira Sans
  • Body: Source Sans Pro
  • Scale: 1.333 modular, 48/36/24/18/16
• Shape Language: Clear columns, rounded rectangles for buttons
• Layout: Grid-based with intuitive tabular alignment
• Motion: Functional transitions, restrained tempo
• Imagery: Minimal, with iconography for categories

7. Signature Design Concept

The public entry page features a composed dashboard view set on a warm background. The primary color highlights actionable CTAs, with a clear, organized grid for dashboard metrics. Rounded-rectangle buttons in bold primary color are used for actions like 'Add Expense'. Category filters are displayed as pill-shaped buttons with accent colors, ensuring a clean and readable interface.

8. Interaction Model & Motion Direction

• Interaction Model: Static
• Motion Tempo: Restrained
• Hero Dimensionality: Flat
• Landing Hero Motion Brief: The dashboard view is the focal subject, with clear text and data visualization. The primary color highlights actionable CTAs, and transitions are functional and purposeful.

9. Non-Functional Requirements

• The application must be runnable locally with clear installation and startup instructions. (explicit)
• The frontend must be responsive and work on both desktop and mobile screens. (explicit)
• The backend must handle errors properly and return appropriate HTTP status codes. (explicit)
• The database must initialize and seed sample expenses automatically. (required_inference)

10. Tech Stack

• Frontend: React
• Backend: Python/FastAPI
• Database: SQLite
• Containerization: Docker/docker-compose

11. Assumptions and Constraints

• The application scope is limited to a small, understandable Mini Expense Tracker. (explicit)
• No authentication, payment systems, or cloud services will be added. (explicit)
• The frontend must communicate with the backend REST API without using hardcoded data. (explicit)

12. Glossary

• Expense manager: The user who interacts with the application to manage expenses.
• REST API: A set of web service endpoints that allow interaction with the backend database.
• SQLite: A lightweight, file-based database used for storing expenses locally.