#requires -version 2
# NB lein -? will give help for the powershell script
#    lein help will give command help for Leiningen
Param(
	[Parameter(Mandatory=$true, Position = 0, HelpMessage = "The command to pass to Leiningen")]
	[string]$command,

	[Parameter(HelpMessage = "The version of Clojure to run.  Needs to be compatible with the version of Leiningen or strange things can happen.")]
	[string]$clojureVersion = "1.1.0", # e.g. 1.2.0-master-20100430.160229-59
	
	[Parameter(HelpMessage = "The location of the Clojure jar.  Don't use this unless you're compiling Clojure from trunk.")]
	[string]$clojureJar, # e.g. "D:\julian\Documents\Projects\oss\circumspec\lib\clojure\1.2.0-master-20100430.160229-59.jar"
	
	[Parameter(HelpMessage = "The version of Leiningen.  1.1.0 is the currently stable version.")]
	[string]$leinVersion = "1.1.0", # e.g. 1.2.0
	
	[Parameter(HelpMessage = "The location of Leiningen standalone jar.  Don't use this unless you're compiling Leiningen from trunk.  Also, make sure it points at an uberjar, not a regular jar.")]
	[string]$leinJar,	# e.g. D:\Julian\Documents\Projects\oss\leiningen\leiningen-standalone.jar
	
	[Parameter(HelpMessage = "Where to download Leiningen from if you're doing a self-install.  Make sure this value is compatible with leinJar and leinVersion or you'll never unpick the mess.")]
	[string]$leinUrl,	# e.g. http://github.com/downloads/technomancy/leiningen/leiningen-1.1.0-standalone.jar
	
	[Parameter(HelpMessage = "Completely overrides Leiningen and runs an arbitrary Clojure command.  Don't use it unless you know what you're doing.")]
	[string]$clojureCommand, 
	
	[Parameter(ValueFromRemainingArguments = $true)]$args
)

(Get-Host).PrivateData.VerboseForegroundColor = "Yellow" # This is pretty badly behaved.  Basic users will like it, but advanced users may want to comment this out.
# Functions

function coalesce {
  (@($args | ?{$_}) + $null)[0]
}
function join($separator, $items) {
	if($items){
		[String]::Join($separator, $items)
	}
}
function get-libs(){
    if(test-path "lib"){
        $jars = join ";" ((ls lib -include *.jar -recur) |% { $_.FullName })
    }
}

function maven-location($product, $version) {
	$format = "{0}`\.m2`\repository`\{1}`\{1}`\{2}`\{1}-{2}.jar";
	return [String]::Format($format, $env:UserProfile, $product, $VERSION)
}

# Argument Defaults
$clojureJar = coalesce $clojureJar $env:clojureJar (maven-location "clojure" $clojureVersion)
$leinJar = coalesce $leinJar $env:leinJar (maven-location "leiningen" $leinVersion)
$leinUrl = coalesce $leinUrl "http://github.com/downloads/technomancy/leiningen/leiningen-$leinVersion-standalone.jar"

# Compute ClassPath
$libs = (get-libs)
$classPath = "src;classes$libs"
# Classes directory needs to exist before the JVM is launched apparently
if(-not (test-path "classes")){
    [void](mkdir classes)
}
# If we are not running from a checkout
if(-not (test-path "classes\leiningen\core.class")){
    if((-not (test-path $leinJar)) -and ($command -ne "self-install")){
        write-error "Leiningen is not installed. Please run `"lein self-install`"."
        exit 1
    }
    $classPath= "$classPath;$leinJar"
}
if(("test", "repl") -contains $command) {
    # tests should be runnable from repl
    $testDir = (get-item -erroraction SilentlyContinue "test").FullName
    $classPath= $testDir + ";" + $classPath
} elseif (("compile", "jar", "uberjar") -contains $command){
	# Deps need to run before the JVM launches for tasks that need them
    if(-not $libs){
        & $myInvocation.MyCommand deps skip-dev
    }
}

write-verbose "Taking Clojure $clojureVersion from $clojureJar"
write-verbose "Taking Leiningen $leinVersion from $leinJar"
$usingClassPath = (join "`n" ($classPath.Split(";")))
write-verbose "Using class path:  `n$usingClassPath`n--End Class Path--"

if($command -eq "self-install"){
    write-verbose "Downloading Leiningen from $leinUrl"
    $jarPath = split-path $leinJar
    if(-not (test-path $jarPath)){
        mkdir $jarPath
    }
    (new-object System.Net.WebClient).DownloadFile($leinUrl, $leinJar)
} else {
	if ($clojureCommand -eq "") {
		if ($command -ne "repl") {
			if ($args) {
				$newArgs = new-object System.Collections.ArrayList
				[void]$newArgs.Add($command)
				$newArgs.AddRange($args)
				$args = $newArgs
			} else {
				$args = @($command)
			}
		}
		$escapedArgs = $args |% { $allArgs = "" } { $allArgs += "\`"$_\`" " } { $allArgs }
		$clojureCommand = "(use 'leiningen.core) (-main $escapedArgs)"
	}
	write-verbose "Clojure command:  $clojureCommand"
    java "-Xbootclasspath/a:$clojureJar" -cp "$classPath" clojure.main -e """$clojureCommand"""
}

# Credits and Notes:  
# Coalesce by Keith Dalby http://solutionizing.net/2008/12/20/powershell-coalesce-and-powershellasp-query-string-parameters/
# Help with parameters by Keith Hill http://stackoverflow.com/questions/2795582/any-way-to-specify-a-non-positional-parameter-in-a-powershell-script
# Heavily based on Roland Sadowski's original lein.ps1, but merged with concepts from Phil Hagelberg's lein.bat
# Anything left might be original :)