# Copyright 2018, pEp Foundation
# This file is part of pEp JNI Adapter
# This file may be used under the terms of the GNU General Public License version 3
# see LICENSE.txt

HERE:=$(dir $(lastword $(MAKEFILE_LIST)))
PLATFORM:=$(shell uname | tr A-Z a-z)
JAVAC_CMD=javac -encoding UTF-8
JAVAH_CMD=javah -encoding UTF-8

# DEV ENV PATHS & CFG
# The build settings are set to a default value which can be overridden by using ./local.conf
#########  DEFAULTS #########
DEBUG=0
PREFIX=$(HOME)
YML2_PATH=$(PREFIX)/src/yml2
YML2_PROC=$(YML2_PATH)/yml2proc $(YML2_OPTS)
YML2_OPTS=--encoding=utf8
ENGINE_LIB_PATH=$(PREFIX)/lib
ENGINE_INC_PATH=$(PREFIX)/include
AD_LIB_PATH=$(PREFIX)/lib
AD_INC_PATH=$(PREFIX)/include


### Guessing JAVA_HOME
ifeq ($(PLATFORM),linux)
    JAVA_HOME=$(subst /bin,,$(dir $(realpath /usr/bin/javac)))
endif



######### Overrides from the config file(s) #########
ifneq ("$(wildcard $(HERE)local.conf)","")
    $(info including: $(HERE)local.conf)
    -include $(HERE)local.conf
else
    $(info Optional build config not found: $(HERE)local.conf)
endif

### Apply config
ENGINE_LIB=-L$(ENGINE_LIB_PATH)
ENGINE_INC=-I$(ENGINE_INC_PATH)
AD_LIB=-L$(AD_LIB_PATH)
AD_INC=-I$(AD_INC_PATH)

ifndef JAVA_HOME
    $(error JAVA_HOME is not set!)
endif

# Guessing USE_JAVAH
# cant be guessed earlier, because it depends on JAVA_HOME which can be set in the local.conf
# Old versions of a Java distribution have a `javah` binary, new version do not and the replacement is "javac -h"
# TODO: dont check for presence of javah, but check if javac -h is supported, because some java (RHEL) has javah but supports javac -h (and javac -h is preferred)
ifndef USE_JAVAH
	DUMMY:=$(shell which $(JAVA_HOME)/bin/javah)
	ifeq ($(.SHELLSTATUS),0)
		USE_JAVAH=1
	endif
endif

JAVA_BIN_DIR=$(JAVA_HOME)/bin

######### C and C++ #########
CXXFLAGS+=-O0 -std=c++11 -fpermissive -fPIC -I$(JAVA_HOME)/include -I$(JAVA_HOME)/include/$(PLATFORM) $(AD_INC) $(ENGINE_INC)
LDFLAGS+=-shared $(ENGINE_LIB) $(AD_LIB)
LDLIBS=-lstdc++ -lpEpEngine -lpEpAdapter
ifneq (,$(findstring g++,$(CXX)))
    CXXFLAGS+=-fdiagnostics-color=always
else ifneq (,$(findstring clang,$(CXX)))
    CXXFLAGS+=-fcolor-diagnostics
endif

### Debug or Release build
ifeq ($(DEBUG),1)
    $(info Debug build (set DEBUG=0 for release build))
    CXXFLAGS+=-g
else
    $(info Release Build (set DEBUG=1 for debug build))
    CXXFLAGS+=-DNDEBUG=1 -O3
endif

### YML_PATH is needed in the environment of every call to a program of the YML2 distribution
export YML_PATH=$(YML2_PATH)

# BEGIN // kryptic hack to to replace a space with a newline
# $(subst ${ },${space}, whatever)
# maybe not well known: define/endef is custom makefile function definition
null :=
space := ${null} ${null}
${space} := ${space}

define \n


endef
# END // kryptic hack to to replace a space with a newline