Minecraft - programming - job plugin?

Hi, I would like to program my own job plugin, but I'm not getting anywhere:
Job: lumberjack
If you cut wood, you will be rewarded with 5 job points per log.
Unfortunately, you get these job points even if you put the wood on the ground yourself and then dismantle it… So with that, you could farm AFK.
How can I query whether the wood has been set or not?

I don't think that is possible because the blocks themselves can't have tags.

Perhaps you can add a property to the class of blocks and then check them. If blocks are placed, they have to be set accordingly.

Otherwise you can e.g. Have a list of the last 10 (wooden) blocks that the player has placed. If a wooden block is now dismantled, you check whether it is in the list and only give points if this is not the case

https://www.spigotmc.org/...er.325494/

B. Have a list of the last 10 (wooden) blocks that the player has placed. If a wooden block is now dismantled, you check whether it is in the list and only give points if this is not the case

Thing is, I have to save all blocks and not just the last 10 …
Because otherwise you place 20 blocks and then you can always mine 10

Then make 100. Nobody will check the system behind