# MQTT Application

## Table of Contents
- [Table of Contents](#Table-of-Contents)
- [Initialisation](#Initialisation)
- [Changing Settings](#changing-settings)
  - [Server Settings](#server-settings)
  - [Publish Settings](#publish-settings)
  - [Text and image position](#text-and-image-position)
- [Changing settings](#Changing-Settings)
- [Getting started](#Getting-started)
  - [Set up](#setting-up)
  - [Topics](#topics)
  - [Colors](#colors)

## Initialisation
The MQTT application should be initialised in the main function:
```c
mqtt_application_init();
```
In case a check for success is wanted, the function will return a '1' on failure and a '0' on success.

## Changing Settings
### Server Settings
Depending on how the MQTT broker is set up on the pc some settings might need to be changed in the mqtt_application.c file.
Make sure you change the corresponding defines to how you have set everything up:
```c
#define SERVER_IP4_A 192
#define SERVER_IP4_B 168
#define SERVER_IP4_C 69
#define SERVER_IP4_D 11
#define SERVER_PORT 1883
```

### Publish Settings
In case you want to change the QOS and retain attributes of the pulbish done by the application, change the corresponding defines:
```c
#define PUBLISH_QOS 2
#define PUBLISH_RETAIN 1
```

### Text and image position
If you want to display the text and images on a different location you can change the following defines(the starting point is the same for both text and images):
```c
#define PRINT_XPOS 50
#define PRINT_YPOS 50
```

## Getting started
In order to use this application you are going to need an MQTT broker:
use this version: mosquitto 1.16.1a: https://mosquitto.org/files/binary/win64/mosquitto-1.6.12a-install-windows-x64.exe

A publisher/subscriber is also required to have:
recommended are: https://mqttx.app/ or https://github.com/eclipse/paho.mqtt-spy/wiki/Downloads

### Setting up
Before testing the application make sure to run the mosquitto broker before starting and connecting the microcontroller.

### Topics
The used topics are:
- getImageList
Upon start up a list of available images will get published here.
- getGifList
Upon start up a list of available gifs will get published here.
- input/setText
Text published here will be displayed on the LCD.
- input/setImage
Publish the correct name + extention for the image/gif you want to display here.
- input/setColor
Publish the color you want the backgroundcolor to be here. This will take effect after changing the text or image/gif.
- input/setTextColor
Publish the color you want the text to be here.

### Colors
Colors should be published using the same format as listed below.
Available colors are:
"LCD_BLUE, LCD_GREEN, LCD_RED, LCD_CYAN, LCD_MAGENTA, LCD_YELLOW, LCD_LIGHTBLUE, LCD_LIGHTGREEN, LCD_LIGHTRED, LCD_LIGHTCYAN, LCD_LIGHTMAGENTA, LCD_LUGHTYELLOW, LCD_DARKBLUE, LCD_DARKGREEN, LCD_DARKRED, LCD_DARKCYAN, LCD_DARKMAGENTA, LCD_DARKYELLOW, LCD_WHITE, LCD_LIGHTGRAY, LCD_GRAY, LCD_DARKGRAY, LCD_BLACK, LCD_BROWN, LCD_ORANGE, LCD_TRANSPARENT"