#!/usr/bin/perl -w
# vim: noet ts=4 sw=4 sts=0 fenc=utf8
# License: The MIT License with modification. See LICENSE for details.
# (C) 2014-2015. Giumo Xavier Clanjor (哆啦比猫/兰威举) <cjxgm@126.com>




my $CC = "clang++";
my $CCFLAGS = "-fdiagnostics-color=always -std=gnu++14 -march=native -O3 -Wall -Wextra";
my $LDFLAGS = "";
my $name = "moge";
my $dest = "build/$name";
my $test = "LIBGL_SHOW_FPS=1 $dest";
my @libs = qw(gl glfw3);	# glm: header-only
my $ver  = `printf "r%s.%s" "\$(git rev-list --count HEAD)" "\$(git rev-parse --short HEAD)"`;





my $COLOR_RST = "\e[0m";
my $COLOR_CMD = "\e[0;32m";
my $COLOR_VER = "\e[0;33m";
my $COLOR_DIR = "\e[0;35m";
my $COLOR_ERR = "\e[1;31m";
my $COLOR_NAME = "\e[0;34m";
my $COLOR_FILE = "\e[1;35m";


my @dirs = qw(build);
my %targets;


sub configure
{
	print "${COLOR_CMD}configuring $COLOR_NAME$name $COLOR_VER$ver\n$COLOR_RST";
	&gen_dep("src");
	&write_makefile;
}


sub gen_dep
{
	my $dir = shift;
	return if $dir =~ /build$/;
	my $parent = shift || "..";

	push @dirs, "build/$dir";
	print "${COLOR_CMD}processing $COLOR_DIR$dir/\n$COLOR_RST";
	&write_forwarding_makefile($dir, $parent);

	for (<$dir/*.cc>) {
		print "${COLOR_CMD}processing $COLOR_FILE$_\n$COLOR_ERR";
		my $deps = `$CC $CCFLAGS -MM "$_"` or die $COLOR_RST;
		print $COLOR_RST;
		$deps =~ /^([^:]+):((.|\n)*)\n$/m or die;
		my $target = $1;
		my $dep = $2;
		$targets{"build/$dir/$target"} = $dep;
	}

	for (<$dir/*/>) {
		s|/$||;
		&gen_dep($_, "$parent/..");
	}
}

sub pkg_config
{
	my $args = shift;
	my $result = `pkg-config $args`;
	$result =~ s/\n+/ /g;
	$result =~ s/\s+$//g;
	$result;
}


sub write_forwarding_makefile
{
	my ($dir, $parent) = @_;
	open my $makefile, ">", "$dir/makefile" or die;
	print $makefile <<EOF;
# vim: noet ts=4 sw=4 sts=0 fenc=utf8
# License: The MIT License with modification. See LICENSE for details.
# (C) 2014-2015. Giumo Xavier Clanjor (哆啦比猫/兰威举) <cjxgm\@126.com>

.PHONY: \${MAKECMDGOALS}

all \$(filter-out all,\${MAKECMDGOALS}): .forward
	@# no op

.forward:
	\@\${MAKE} --no-print-directory -C $parent \${MAKECMDGOALS} || true

EOF
	close $makefile
}

sub write_makefile
{
	open my $makefile, ">", "makefile" or die;
	print $makefile <<EOF;
# vim: noet ts=4 sw=4 sts=0 fenc=utf8
# License: The MIT License with modification. See LICENSE for details.
# (C) 2014-2015. Giumo Xavier Clanjor (哆啦比猫/兰威举) <cjxgm\@126.com>
VERSION = $ver
BUNDLE = $name-\$(VERSION)

# compiler and flags
CXX = $CC
LD = \$(CXX)
CCFLAGS = $CCFLAGS
LDFLAGS = $LDFLAGS

EOF
	print $makefile "CCFLAGS += " . &pkg_config("--cflags $_") . "\n" for @libs;
	print $makefile "LDFLAGS += " . &pkg_config("--libs   $_") . "\n" for @libs;
	print $makefile <<EOF;


# named colors
COLOR_RST = $COLOR_RST
COLOR_CMD = $COLOR_CMD
COLOR_ARG = $COLOR_FILE


# phonies
.PHONY: all release-all clean cleanall rebuild release reconf test bundle commit analyze diff trace log
all: init app
release-all: CCFLAGS += -DRELEASE
release-all: all
clean: makefile
	\@echo "\$(COLOR_CMD)cleaning\$(COLOR_RST)"
	rm -rf build
	rm -f trace
	rm -rf \$(BUNDLE)
cleanall: clean
	rm -f `find . -name 'makefile'`
	rm -f $dest
	rm -rf $name-*
rebuild:
	\$(MAKE) --no-print-directory clean
	\$(MAKE) --no-print-directory all
release:
	\$(MAKE) --no-print-directory clean
	\$(MAKE) --no-print-directory release-all
reconf:
	\@echo "\$(COLOR_CMD)reconfiguring\$(COLOR_RST)"
	./configure
test: all
	\@echo "\$(COLOR_CMD)testing" "\$(COLOR_ARG)$name\$(COLOR_RST)"
	$test
commit: cleanall
	git add .
	git diff --cached
	env LANG=C git commit -a || true
	./configure
bundle: release
	\@echo "\$(COLOR_CMD)bundling" "\$(COLOR_ARG)$name\$(COLOR_RST)"
	rm -rf \$(BUNDLE)
	mkdir -p \$(BUNDLE)
	cp -r configure makefile src/ \$(BUNDLE)
	cp -r $dest \$(BUNDLE)/\$(BUNDLE)
	rm -f `find \$(BUNDLE) -name '.*'`
	tar cvfJ \$(BUNDLE).tar.xz \$(BUNDLE)
analyze: clean
	\@echo "\$(COLOR_CMD)analyzing" "\$(COLOR_ARG)$name\$(COLOR_RST)"
	scan-build -V --use-c++=$CC make
trace: all
	\@echo "\$(COLOR_CMD)tracing" "\$(COLOR_ARG)$name\$(COLOR_RST)"
	apitrace trace -o trace timeout 10s $dest || true
	qapitrace trace
diff:
	git diff --cached
log:
	git log --oneline --graph --decorate


# build rules
init: makefile @dirs
app: makefile $dest
makefile: configure
	\@echo "\$(COLOR_CMD)reconfiguring\$(COLOR_RST)"
	./configure
EOF
	print $makefile <<EOF for @dirs;
$_:
	\@echo "\$(COLOR_CMD)making directory" "\$(COLOR_ARG)\$@\$(COLOR_RST)"
	mkdir -p $_
EOF
	print $makefile <<EOF;
build/%.o: %.cc
	\@echo "\$(COLOR_CMD)compiling" "\$(COLOR_ARG)\$@\$(COLOR_RST)"
	\$(CXX) -c -o \$@ \$< \$(CCFLAGS)
$dest: @{[keys %targets]}
	\@echo "\$(COLOR_CMD)linking" "\$(COLOR_ARG)\$@\$(COLOR_RST)"
	\$(LD) -o \$@ \$^ \$(LDFLAGS)


# dependencies
EOF
	print $makefile "$_:$targets{$_} makefile\n" for keys %targets;
	print $makefile "\n";
	close $makefile
}


&configure;