# GUI-CLI Protocol

Protocol version: <b>"0.2"</b>

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## 0. Connect to the server

The GUI creates a new instance of the CLI with the entered IP Address as a paramater. The CLI then tries to establish a connection to the given server and tells the GUI if the connection was successful.

CLI:
```
{
	"command": "connect",
	"accept": bool,
	"error": string
}
```

## 1. Start a connection

To connect to a server, the CLI has to do a version check. Once that is successful, the GUI will pass the username and password to establish a connection.

### 1.1 Version check
CLI:
```
{
	"command": "version",
	"serverversion": string,
	"clientversion": string,
	"accept": bool
}
```

If `accept` is `true` the connection is valid. Else the connection will be terminated after the server answered.


## 1.2 Login / Signup

The GUI will send the username and password right after another into the pipe. If the response contains a "true" for accept, the login was successful.

### 1.2.1 Login
GUI:
```
	write: username
	write: password
```

CLI:
```
{
	"command": "login",
	"accept": bool,
	"error": string
}
```

If `accept` is `true` the connection is valid and the user is logged in. Else `error` has an error string and the connection will be terminated after the server answered.

### 1.2.2 Signup
GUI:
```
	write: #ToBeAdded
```

Server:
```
{
	"command": "signup",
	#ToBeAdded
}
```

If `accept` is `true` the connection is valid and the user is logged in and signed up. Else `error` has an error string and the connection will be terminated after the server answered.


## 2. Sending commands

Commands can be sent by the client after a connection has been negotiated (See 1).
Commands can be used unrelated to each other.

### 2.1 Status command
GUI:
```
write: "status"
```

CLI:
```
{
	"command": "status",
	"response": string
}
```

### 2.2 List command
`list` to request a list download.

#### 2.2.1 list - request file list download
GUI:
```
{
	write: "list"
}
```
CLI:
```
{
	"command": "list",
  "accept": bool,
	"names": string[],
	"error": string
}
```


### 2.3 Put command

Put is split in two commands. `put` to request a file upload and `putdata` to get the information about an ongoing upload.

#### 2.3.1 put - request upload
GUI:
```
write: "put" file_path
```

CLI:
```
{
	"command": "put",
	"accept": bool,
	"file": string,
	"error": string
}
```
If `accept` is `true` the connection is valid and the client can start sending the file. Else the put request was rejected and is hereby canceled. `error` should contain an error string if the request was rejected.


#### 2.3.2 putdata - upload data
CLI:
```
{
	"command": "putdata",
	"file": string,
	"speed": float,
	"cancel": bool,
	"error": string
}
```
If `cancel` is `true` then the upload of the file is canceled and an error message should be in `error`.
`speed` shall contain a float describing the upload speed in kB/s.


### 2.4 Get command

Get is split in two commands. `get` to request a file download and `getdata` to get the information about an ongoing download.

#### 2.4.1 get - request download

GUI:
```
write: "get" file_name
```

CLI:
```
{
	"command": "get",
	"accept": bool,
	"file": string,
	"error": string
}
```
If `accept` is `true` the connection is valid and the server can start sending the file. Else the get request was rejected and is hereby canceled. `error` should contain an error string if the request was rejected.

#### 2.4.2 getdata - download data

CLI:
```
{
	"command": "putdata",
	"file": string,
	"speed": float,
	"cancel": bool,
	"error": string
}
```

If `cancel` is `true` then the download of the file is canceled and an error message should be in `error`.
`speed` shall contain a float describing the download speed in kB/s.


### TODO


## 3. Disconnect

GUI:
```
{
	write: "disconnect"
}
```

CLI:
```
{
	"command": "disconnect",
	"accept": bool
}
```

If `accept` is true, the connection is closed and the program can exit.