IntelliJ IDEA Java decompiler wrapper script for PowerShell

fernflower.ps1

############################################################################
#
#  IntelliJ IDEA Java Decompiler wrapper script for Windows
#
#  @see https://stackoverflow.com/questions/28389006/how-to-decompile-to-java-files-intellij-idea/30106981
#  @see https://github.com/JetBrains/intellij-community/tree/master/plugins/java-decompiler/engine
#
############################################################################

$IDEA_PATH = "$Env:ProgramFiles\JetBrains\IntelliJ IDEA 2020.1.1"
# Add default JVM options here. You can also use JAVA_OPTS to pass JVM options to this script.
$DEFAULT_JVM_OPTS = '-Xms128M', '-Xmx4g', '-XX:+UseG1GC'
$FERNFLOWER_OPTS = '-hdc=0', '-dgs=1', '-rsy=1', '-rbr=1', '-lit=1', '-nls=1', '-mpm=60'

$CLASSPATH = Resolve-Path "$IDEA_PATH\plugins\java-decompiler\lib\java-decompiler.jar"
$CLASS = 'org.jetbrains.java.decompiler.main.decompiler.ConsoleDecompiler'

# Find java.exe
function Find-Java {
	[OutputType([String])]
	param ()

	process {
		if ($null -ne $Env:JAVA_HOME) {
			try {
				$JAVA_EXE = Join-Path $Env:JAVA_HOME (Join-Path 'bin' 'java.exe')

				Test-Path -PathType Leaf $JAVA_EXE -ErrorAction Stop > $null

				return $JAVA_EXE
			} catch {
				throw @"
JAVA_HOME is set to an invalid directory: $Env:JAVA_HOME

Please set the JAVA_HOME variable in your environment to match the location of your Java installation.
"@
			}
		} else {
			try {
				$JAVA_EXE = 'java.exe'

				Get-Command -Type Application $JAVA_EXE -ErrorAction Stop > $null

				return $JAVA_EXE
			} catch {
				throw @"
JAVA_HOME is not set and no 'java' command could be found in your PATH.

Please set the JAVA_HOME variable in your environment to match the location of your Java installation.
"@
			}
		}
	}
}

function Invoke-WhenInput {
	param (
		[Parameter(Mandatory, ValueFromPipelineByPropertyName)]
		[ValidateNotNull()]
		[ScriptBlock]$ExpectingInput,
		[Parameter(Mandatory, ValueFromPipelineByPropertyName)]
		[ValidateNotNull()]
		[ScriptBlock]$NotExpectingInput,
		[Parameter(ValueFromRemainingArguments, ValueFromPipelineByPropertyName)]
		[AllowEmptyCollection()]
		[Object[]]$ArgumentList
	)

	process {
		foreach ($arg in $ArgumentList) {
			if ($arg -NotLike '-*') {
				return & $ExpectingInput @ArgumentList

				break
			}
		}

		return & $NotExpectingInput @ArgumentList
	}
}

function Invoke-WithInput {
	$Dest = $null
	$IsTemp = $false

	if (
		(Test-Path -PathType Container -Path $args[-1]) -and
		($null -ne $args[-2]) -and ($args[-2] -NotLike '-*')
	) {
		$args = $args[0..($args.Length - 1)]
		$Dest = $args[-1]
	} else {
		$Dest = [System.IO.Path]::GetRandomFileName()
		New-Item -ItemType Directory -Path $Dest > $null
		$IsTemp = $true
	}

	& (Find-Java) @DEFAULT_JVM_OPTS @JAVA_OPTS -classpath $CLASSPATH $CLASS @($FERNFLOWER_OPTS + $args) $Dest
	$ExitCode = $LASTEXICODE

	foreach ($Archive in Get-ChildItem -Path $Dest -Recurse -Attributes !Directory) {
		$NewArchiveName = "$($Archive.BaseName).zip"
		$NewArchivePath = Join-Path -Path $Dest -ChildPath $NewArchiveName
		$NewArchiveDestionation = Join-Path -Path $Dest -ChildPath $Archive.BaseName

		Rename-Item -Path (Join-Path -Path $Dest -ChildPath $Archive) -NewName $NewArchiveName

		try {
			Expand-Archive -Path $NewArchivePath -DestinationPath $NewArchiveDestionation -ErrorAction Stop
			Remove-Item -Path $NewArchivePath
		} catch {
			Rename-Item -Path $NewArchivePath -NewName $Archive.Name
		}
	}

	$LASTEXICODE = $ExitCode

	if ($IsTemp) {
		Move-Item -Path $Dest\* -Destination .
		Remove-Item -Path $Dest
	}
}

function Invoke-WithoutInput {
	& (Find-Java) @DEFAULT_JVM_OPTS @JAVA_OPTS -classpath $CLASSPATH $CLASS @args
}

Invoke-WhenInput -ExpectingInput ${Function:Invoke-WithInput} -NotExpectingInput ${Function:Invoke-WithoutInput} -ArgumentList $args
exit $LASTEXICODE