SHomeSystem

A smart home automation system built with C/C++ (for the backend server) and Qt (for the client interface). The server uses SQLite as its database, and the client relies on Qt widgets, charts, and networking modules.

Table of Contents

1. Overview
2. Features
3. Project Structure
4. Prerequisites
5. Building the Server on Linux
6. Running the Server
7. Building the Client with Qt Creator
8. Running the Client
9. Key Source Files Explanation
   • Server Side
   • Client Side
10. Troubleshooting

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1. Overview

SHomeSystem allows you to control and monitor home devices (air conditioners, lights, humidifiers, etc.) through a client application built with Qt. A C-based server handles the logic of registering users, logging them in, and receiving device status updates or analysis requests. The server uses SQLite for data storage and microhttpd along with libcurl for HTTP APIs.

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2. Features

• User Authentication: Registration and login using SQLite as a credentials store.
• Device Control: Toggle states (on/off) and set timers for air conditioners, lights, humidifiers, etc.
• Data Analysis: Retrieve daily power consumption data for each device via the server.
• Charts & Visualization: Qt Charts (line charts, bar charts) for monitoring power usage and environmental data (temperature, humidity).
• Weather Updates: Fetch external weather data for demonstration (e.g., from a third-party API).

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3. Project Structure

A simplified view of important files and folders:

SHomeSystem/
│
├── client/
│   ├── src/
│   │   ├── SHomeSystem.pro             # Qt project file
│   │   ├── main.cpp
│   │   ├── widget.cpp/.h/.ui
│   │   ├── tabwidget.cpp/.h/.ui
│   │   ├── loginview.cpp/.h/.ui
│   │   ├── registerview.cpp/.h/.ui
│   │   ├── datawidget.cpp/.h/.ui
│   │   ├── environmentwidget.cpp/.h/.ui
│   │   ├── weatherwidget.cpp/.h/.ui
│   │   ├── device.cpp/.h
│   │   ├── executor.cpp/.h
│   │   ├── sensormodule.cpp/.h
│   │   ├── communicationinterface.cpp/.h
│   │   └── userdb.cpp/.h
│   └── ...
│
├── database/
│   └── SHomedb.db                      # Example SQLite database
│
├── server/
│   └── src/
│       ├── api.c/.h
│       ├── db.c/.h
│       ├── server.c/.h
│       ├── util.c/.h
│       ├── main.c
│       ├── k_program                   # Compiled server binary (example)
│       └── ...
│
└── readme.md                           # This README

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4. Prerequisites

• Linux environment (e.g., Ubuntu, Debian, etc.)
• GCC or Clang toolchain for compiling C/C++ code
• Qt Creator/Qt 5 or Qt 6 libraries for building the client
• SQLite3, cURL, libmicrohttpd, and cJSON libraries (installed on your Linux system)

Example (Ubuntu/Debian) installation commands:

sudo apt-get update
sudo apt-get install build-essential cmake git \
                     libsqlite3-dev libcurl4-openssl-dev \
                     libmicrohttpd-dev libcjson-dev \
                     qtbase5-dev qt5-qmake qtmultimedia5-dev \
                     libqt5charts5-dev

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5. Building the Server on Linux

1. Move to the source directory (example below assumes you placed the repo under C:\Users\Bling\Desktop\SHomeSystem, mounted in /mnt/c/Users/Bling/Desktop/SHomeSystem in WSL, for instance):

   cd /mnt/c/Users/Bling/Desktop/SHomeSystem/server/src

2. Compile the server files. Below is an example of how you might compile manually:

   # Compile util.c
   gcc -c util.c -o util.o -I/usr/include/cjson
   
   # Compile db.c
   gcc -c db.c -o db.o -I/usr/include/cjson
   
   # Compile api.c (if needed)
   gcc -c api.c -o api.o -I/usr/include/cjson
   
   # Compile server.c
   gcc -c server.c -o server.o -I/usr/include/cjson
   
   # Compile main.c
   gcc -c main.c -o main.o -I/usr/include/cjson
   
   # Link everything
   gcc api.o db.o main.o server.o util.o -o k_program \
       -lmicrohttpd -lcurl -lcjson -lsqlite3

   This produces an executable (named k_program in the example).

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6. Running the Server

1. Make sure the SQLite database file (SHomedb.db) is in the correct location (the server expects it at ../../database/SHomedb.db by default, or you can edit the path in server.c / db.c).

2. Run the server:

   ./k_program

   • The server starts on port 8080.
   • Press Enter in the terminal to stop it.

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7. Building the Client with Qt Creator

1. Open Qt Creator.
2. Open the .pro project file located at:

   SHomeSystem/client/src/SHomeSystem.pro
   

3. Configure the kit (Qt version, compiler, etc.) in Qt Creator if needed.
4. Click "Build" or use the Qt Creator build menu to compile the client.

The .pro file includes modules like charts, sql, and network, which are required for the various widgets, chart displays, and networking operations.

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8. Running the Client

After successful compilation in Qt Creator:

1. Run the generated SHomeSystem application (Qt Creator’s green “Run” button).
2. Graphical UI will appear with tabs for device control, data analysis, login, and registration.
3. Ensure your server is running on 127.0.0.1:8080 (or the address you’ve configured in the code). Some functionalities, such as data retrieval and login, require the server to be online.

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9. Key Source Files Explanation

Server Side

• main.c
  Entry point that calls start_server().

• server.c / server.h

  • Implements the microhttpd-based server, listens on port 8080.
  • Routes incoming requests (e.g. /user/login, /data/updateAirData, etc.) to specific handler functions in api.c.

• api.c / api.h

  • Contains logic for handling user registration, login, device data updates, and weather data fetching.
  • Example functions: handleUserRegister, handleUserLogin, analyzeDataAirTotalPower, etc.

• db.c / db.h

  • Manages SQLite operations, including saveUser, getUserData, getDeviceData, etc.
  • openDatabase and closeDatabase handle the DB connection.

• util.c / util.h

  • Shared helper functions for date/time retrieval, power consumption calculations, and error handling.

Client Side

• SHomeSystem.pro
  Qt project file listing the required modules (core gui charts sql network) and source files.

• main.cpp
  Entry point for the Qt application. Launches the main Widget.

• widget.cpp/.h/.ui
  Basic entry screen or main window container.

• tabwidget.cpp/.h/.ui
  Contains multiple tabs for controlling devices (air conditioners, lights, humidifiers), setting timers, and sending requests to the server.

• loginview.cpp/.h/.ui & registerview.cpp/.h/.ui
  Handle user login and registration with the server’s /user/login and /user/register endpoints.

• datawidget.cpp/.h/.ui
  Displays bar charts for energy consumption data retrieved from the server.

• environmentwidget.cpp/.h/.ui
  Displays line charts for temperature/humidity data.

• device.cpp/.h
  Object-oriented classes for representing devices (e.g., AirConditioner, Light, Humidifier).

• executor.cpp/.h
  Simulates sending commands to devices (shows pop-up messages, logs actions).

• sensormodule.cpp/.h
  Demonstrates reading random sensor values and automatically controlling devices (e.g., turning on the air conditioner if it’s too hot).

• communicationinterface.cpp/.h
  Illustrates how a JSON-based request might be handled within the client side, though the server portion uses C and microhttpd.

• userdb.cpp/.h
  Example class for working with user data in the client if needed (though the official user data is stored in the server’s SQLite).

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10. Troubleshooting

• Library Linking Errors: Ensure you have installed libmicrohttpd-dev, libcurl-dev, libcjson-dev, and libsqlite3-dev.
• SQLite Database Not Found: Adjust the path in the server source code (db.c) or place SHomedb.db in the ../../database/ relative path from server/src/.
• Network Errors (Client/Server)**: Verify the server is running on port 8080, and the client is trying to connect to 127.0.0.1:8080 (or your chosen IP/port).
• Qt Charts Not Displaying: Confirm you have added charts to QT += charts in the .pro file and installed libqt5charts5-dev.

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