Resource Planning Widget / Starting point

Hello developer colleagues!

I have a question regarding resource planning - which widget should I use, how should I start?

So this is the task:
For planning which employees are on holiday/are here I need a table which can be easily modified with the mouse.
The first column hast all employee names, the first row has a timerange (a month in days).
Then I would like to be able to select the leaves with the mouse by drawing it into the grid/table.

So it should look like this:
[font=courier new]

±-----------±–±–±–±–±----±—+
| Employess | 1 | 2 | 3 | 4 | … | 31 |
±-----------±–±–±–±–±----±—+
| Max Muster | | x | | | … | |
| Tom Test | | | | | … | |
| John Doe | | x | x | x | … | |
±-----------±–±–±–±–±----±—+
[/font]
In this example “John Doe” will be on holiday from 2nd to 4th of this month.

It would be no problem to retrieve the data and display a table, but how could I achieve that the user can click, let’s say on the 2nd day and drag the mouse to the 18th day to create a new holiday in the given timespan?

Any hints are welcome!
Thank you!