Decrypt and encrypt PKM files 3rd Gen

[MiguelxTx]

Hi, im working on a C# project, the objective of the project is, read .pkm file see the information (pid, nickname, atk ivs, def ivs....) and change for explame the nickname and save again into .pkm file.

Im working only for 3 gen (fire red, leaf green, ruby, sapphire) obviously read the bytes (100) is the too much easy step, but need to "decrypt" that bytes to show the info of pkm.

Need help to this, i read bulbapedia to see the pkm file structure but can't understand the algorithm to this.

[wrathsoffire76]

This picture seems to be the best visual representation of the Pokémon file structure.

Link 

[theSLAYER]

Wow, did you reply to a post from a month ago? lol.

In any case,
One needs to understand that the data are shuffled based one for blocks, G,A,E,M,
And how those blocks are shuffled are determined by the PID that Pokemon has (and PID data isn't encrypted)