#!/usr/bin/hphpi -f 
<?php

define( 'MW_CONFIG_CALLBACK', 'MakeHipHop::noConfigNeeded' );
require( __DIR__ . '/../Maintenance.php' );

class MakeHipHop extends Maintenance {
	function noConfigNeeded() {}

	function execute() {
		global $wgHipHopBuildDirectory;

		$startTime = time();

		$thisDir = realpath( __DIR__ );
		$IP = realpath( "$thisDir/../.." );
		if ( strval( $wgHipHopBuildDirectory ) !== '' ) {
			$buildDir = $wgHipHopBuildDirectory;
		} else {
			$buildDir = "$thisDir/build";
		}
		$extensionsDir = realpath( MWInit::getExtensionsDirectory() );
		$outDir = "$buildDir/hiphop-output";
		$persistentDir = "$buildDir/persistent";

		if ( !is_dir( $buildDir ) ) {
			mkdir( $buildDir, 0777, true );
		}
		if ( !is_dir( $persistentDir ) ) {
			mkdir( $persistentDir, 0777, true );
		}

		if ( realpath( "$IP/../phase3" ) !== $IP
			|| realpath( "$IP/../extensions" ) !== $extensionsDir )
		{
			# Set up a fake source directory with the correct layout
			$sourceBase = "$buildDir/source";
			$this->setupFakeSourceBase( $IP, $extensionsDir, $sourceBase );
		} else {
			$sourceBase = realpath( "$IP/.." );
			unlink( "$buildDir/source" );
		}

		# With the CentOS RPMs, you just get g++44, no g++, so we have to 
		# use the environment
		if ( isset( $_ENV['CXX'] ) ) {
			$cxx = $_ENV['CXX'];
		} else {
			$cxx = 'g++';
		}

		# Create a function that provides the HipHop compiler version, and 
		# doesn't exist when MediaWiki is invoked in interpreter mode.
		$version = str_replace( PHP_EOL, ' ', trim( `hphp --version` ) );
		file_put_contents(
			"$buildDir/HipHopCompilerVersion.php",
			"<" . "?php\n" .
			"function wfHipHopCompilerVersion() {\n" .
			"return " . var_export( $version, true ) . ";\n" .
			"}\n"
		);

		# Generate the file list
		$files = $this->getFileList();
		file_put_contents(
			"$buildDir/file-list",
			implode( "\n", $files ) . "\n" );

		# Generate the C++
		passthru(
			'hphp' .
			' --target=cpp' .
			' --format=file' .
			' --input-dir=' . wfEscapeShellArg( $sourceBase ) .
			' --input-list=' . wfEscapeShellArg( "$buildDir/file-list" ) .
			' --inputs=' . wfEscapeShellArg( "$buildDir/HipHopCompilerVersion.php" ) .
			' -c ' . wfEscapeShellArg( "$thisDir/compiler.conf" ) .
			' --parse-on-demand=false' .
			' --program=mediawiki-hphp' .
			' --output-dir=' . wfEscapeShellArg( $outDir ) .
			' --log=3', $ret );

		if ( $ret ) {
			$this->error( "hphp hit an error. Stopping build.\n" );
			exit( 1 );
		}

		# Sanity check, quickly make sure we've got an output directory
		if( !is_dir( $outDir ) ) {
			$this->error( "No output directory", true );
		}

		# Warn about volatile classes
		$this->checkVolatileClasses( $outDir );

		# Copy the generated C++ files into the source directory for cmake
		$iter = new RecursiveIteratorIterator( 
			new RecursiveDirectoryIterator( $outDir ),
			RecursiveIteratorIterator::SELF_FIRST );
		$sourceFiles = array();
		$regenerateMakefile = false;
		$numFiles = 0;
		$numFilesChanged = 0;
		foreach ( $iter as $sourcePath => $file ) {
			$name = substr( $sourcePath, strlen( $outDir ) + 1 );
			$sourceFiles[$name] = true;
			$destPath = "$persistentDir/$name";
			if ( $file->isDir() ) {
				if ( !is_dir( $destPath ) ) {
					mkdir( $destPath );
				}
				continue;
			}

			$numFiles++;
			# Remove any files that weren't touched, these may have been removed
			# from file-list, we should not compile them
			if ( $file->getMTime() < $startTime ) {
				if ( file_exists( $destPath ) ) {
					unlink( $destPath );
					# Files removed, regenerate the makefile
					$regenerateMakefile = true;
				}
				unlink( $sourcePath );
				$numFilesChanged++;
				continue;
			}

			if ( file_exists( $destPath ) ) {
				$sourceHash = md5( file_get_contents( $sourcePath ) );
				$destHash = md5( file_get_contents( $destPath ) );
				if ( $sourceHash == $destHash ) {
					continue;
				}
			} else {
				# New files added, regenerate the makefile
				$regenerateMakefile = true;
			}
			$numFilesChanged++;
			copy( $sourcePath, $destPath );
		}

		echo "MediaWiki: $numFilesChanged files changed out of $numFiles\n";

		if ( !file_exists( "$persistentDir/CMakeLists.txt" ) ) {
			# Run cmake for the first time
			$regenerateMakefile = true;
		}

		# Do our own version of $HPHP_HOME/bin/run.sh, which isn't so broken.
		# HipHop's RELEASE mode seems to be stuck always on, so symbols get 
		# stripped. Also we will try keeping the generated .o files instead of 
		# throwing away hours of CPU time every time you make a typo.

		chdir( $persistentDir );

		if ( $regenerateMakefile ) {
			copy( $_ENV['HPHP_HOME'] . '/bin/CMakeLists.base.txt', 
				"$persistentDir/CMakeLists.txt" );

			if ( file_exists( "$persistentDir/CMakeCache.txt" ) ) {
				unlink( "$persistentDir/CMakeCache.txt" );
			}

			$cmd = 'cmake' .
				" -D CMAKE_BUILD_TYPE:string=" . wfEscapeShellArg( $GLOBALS['wgHipHopBuildType'] ) .
				' -D PROGRAM_NAME:string=mediawiki-hphp';
			
			if ( file_exists( '/usr/bin/ccache' ) ) {
				$cmd .= ' -D CMAKE_CXX_COMPILER:string=ccache' .
					' -D CMAKE_CXX_COMPILER_ARG1:string=' . wfEscapeShellArg( $cxx );
			}

			$cmd .= ' .';
			echo "$cmd\n";
			passthru( $cmd );
		}

		# Determine appropriate make concurrency
		# Compilation can take a lot of memory, let's assume that that is limiting.
		$procs = $this->getNumProcs();
		
		# Run make. This is the slow step.
		passthru( 'make -j' . wfEscapeShellArg( $procs ) );

		$elapsed = time() - $startTime;

		echo "Completed in ";
		if ( $elapsed >= 3600 ) {
			$hours = floor( $elapsed / 3600 );
			echo $hours . 'h ';
			$elapsed -= $hours * 3600;
		}
		if ( $elapsed >= 60 ) {
			$minutes = floor( $elapsed / 60 );
			echo $minutes . 'm ';
			$elapsed -= $minutes * 60;
		}
		echo $elapsed . "s\n";
		echo "The MediaWiki executable is at $buildDir/persistent/mediawiki-hphp\n";
	}

	function checkVolatileClasses( $dir ) {
		$lines = file( "$dir/sys/dynamic_table_class.cpp" );
		$classes = array();
		foreach ( $lines as $line ) {
			if ( preg_match( '/^\s+\(const char \*\)"([^"]*)", \(const char \*\)-1/', $line, $m ) ) {
				$classes[] = $m[1];
			}
		}
		if ( !count( $classes ) ) {
			print "No volatile classes found\n";
			return;
		}
		sort( $classes );
		$classes = array_unique( $classes );
		print "WARNING: The following classes are volatile: " . implode( ', ', $classes ) . "\n";
	}

	function getNumProcs() {
		global $wgHipHopCompilerProcs;
		if ( $wgHipHopCompilerProcs !== 'detect' ) {
			return intval( $wgHipHopCompilerProcs );
		}

		if ( !file_exists( '/proc/meminfo' ) ) {
			return 1;
		}
		$mem = false;
		foreach ( file( '/proc/meminfo' ) as $line ) {
			if ( preg_match( '/^MemTotal:\s+(\d+)\s+kB/', $line, $m ) ) {
				$mem = intval( $m[1] );
				break;
			}
		}
		if ( $mem ) {
			// At least one process
			return max( 1, floor( $mem / 1000000 ) );
		} else {
			return 1;
		}
	}

	function setupFakeSourceBase( $phase3, $extensions, $dest ) {
		if ( !file_exists( $dest ) ) {
			mkdir( $dest, 0777, true );
		}

		$this->forceCreateLink( "$dest/phase3", $phase3 );
		$this->forceCreateLink( "$dest/extensions", $extensions );
	}

	function forceCreateLink( $target, $link ) {
		if ( file_exists( $target ) ) {
			if ( readlink( $target ) === $link ) {
				return;
			}
			unlink( $target );
		}
		symlink( $target, $link );
	}

	function getFileList() {
		global $wgAutoloadClasses, $wgAutoloadLocalClasses, $wgCompiledFiles;
		$inputFiles = array_merge(
			array_values( $wgAutoloadClasses ),
			array_values( $wgAutoloadLocalClasses ),
			$wgCompiledFiles
		);
		$processedFiles = array();
		foreach ( $inputFiles as $file ) {
			if ( substr( $file, 0, 1 ) === '/' ) {
				$processedFiles[] = $this->absoluteToRelative( $file );
			} elseif ( preg_match( '/^extensions/', $file ) ) {
				$processedFiles[] = $file;
			} else {
				$processedFiles[] = "phase3/$file";
			}
		}

		$extraCoreFiles = array_map( 'trim', file( __DIR__ . '/extra-files' ) );
		foreach ( $extraCoreFiles as $file ) {
			if ( $file === '' ) {
				continue;
			}
			$processedFiles[] = "phase3/$file";
		}
		return array_unique( $processedFiles );
	}

	function absoluteToRelative( $file ) {
		global $IP;

		$coreBase = realpath( $IP ) . '/';
		$extBase = realpath( MWInit::getExtensionsDirectory() ) . '/';
		$file = realpath( $file );

		if ( substr( $file, 0, strlen( $extBase ) ) === $extBase ) {
			return 'extensions/' . substr( $file, strlen( $extBase ) );
		} elseif ( substr( $file, 0, strlen( $coreBase ) ) === $coreBase ) {
			return 'phase3/' . substr( $file, strlen( $coreBase ) );
		} else {
			$this->error( "The following file is registered for compilation but is not in \$IP or " .
				"\$wgExtensionsDirectory: $file \n" );
			exit( 1 );
		}
	}
}

$maintClass = 'MakeHipHop';
require_once( RUN_MAINTENANCE_IF_MAIN );