regdiff Playnite Extension: Registry snapshot and comparison

extension.yaml

Name: regdiff
Author: Blake Burkhart
Version: 1.1
Module: regdiff.ps1
Type: Script
Functions: 

regdiff.ps1

# regdiff 1.1
# Discover game settings/save games in the registry.

# This extension takes a snapshot of all registry keys before and after running
# every game. The snapshot and their difference is saved into the game 
# installation directory.

# This only works if new keys are created while running the game (i.e. the very
# first time the game is run on your computer.)

# Only registry keys are listed, not names of values.

# Note, this does slow down launching games. You can uncomment two places below
# to only run the diff once per game. Delete the diff file to cause the script
# to rerun.

function SnapshotFileName ($game, $type) {
    # Include game id to make files unique even if multiple games are in the same directory
    $id = [string]$game.Id
    Join-Path $game.InstallDirectory "regdiff-${type}-${id}.txt"
}

function OnGameStarting ($game)
{
    $diffFile = SnapshotFileName $game "diff"
    if(Test-Path $diffFile -PathType Leaf) {
        # Uncomment to skip running if diff already exists
        # return
    }
    $__logger.Info("regdiff OnGameStarting: $($game.Name)")
    $global:starting = Get-ChildItem -Path hkcu:\ -Recurse -Name
}

function OnGameStopped ($game, $elapsedSeconds)
{
    $diffFile = SnapshotFileName $game "diff"
    if(Test-Path $diffFile -PathType Leaf) {
        # Uncomment to skip running if diff already exists
        # return
    }
    $__logger.Info("regdiff OnGameStopped: $($game.Name)")
    
    Start-Job -ArgumentList $diffFile, $global:starting {
        Param($diffFile, $starting)
        $stopped = Get-ChildItem -Path hkcu:\ -Recurse -Name
        $diff = Compare-Object -PassThru -CaseSensitive $starting $stopped
        # Append the diff to the diff file (or create it if it does not exist)
        $diff >> $diffFile
    }
}