SDK ?= /usr/lib/android-sdk
NDK ?= /usr/lib/android-ndk
CCSYSROOT = $(NDK)/sysroot
ISYS = $(CCSYSROOT)/usr/include/aarch64-linux-android
LDSYSROOT = $(NDK)/platforms/android-23/arch-arm64
PLATFORM_JAR = $(SDK)/platforms/android-23/android.jar
TCPATH = $(NDK)/toolchains/llvm/prebuilt/linux-$(shell uname -m)/bin
TC = $(TCPATH)/aarch64-linux-android23-

src = $(wildcard src/*.c) $(wildcard src/android/*.c)
obj = $(src:.c=.arm64.o)
dep = $(src:.c=.d)
name = andemo
lib_so = lib$(name).so

pkgprefix = com.mutantstargoat
pkg = $(pkgprefix).$(name)
act = android.app.NativeActivity

warn = -pedantic -Wall
dbg = -g
opt = -O3 -ffast-math -fno-strict-aliasing
incdir = -Isrc

CC = $(TC)clang
CFLAGS = --sysroot=$(CCSYSROOT) -isystem=$(ISYS) $(warn) $(dbg) $(opt) $(def) $(incdir) -fPIC -fcommon -MMD
LDFLAGS = --sysroot=$(LDSYSROOT) -lEGL -lGLESv2

$(name).apk: $(name).aligned.apk keystore.jks
	apksigner sign --ks keystore.jks --ks-key-alias androidkey --ks-pass pass:android --key-pass pass:android --out $@ $<

keystore.jks:
	keytool -genkeypair -keystore $@ -alias androidkey -validity 10000 -keyalg RSA -keysize 2048 -storepass android -keypass android

$(name).aligned.apk: $(name).unsigned.apk
	zipalign -f -p 4 $< $@

$(name).unsigned.apk: $(lib_so) AndroidManifest.xml
	mkdir -p apkbuild/lib/arm64-v8a
	cp $(lib_so) apkbuild/lib/arm64-v8a
	aapt package -f -v -F $@ -I $(PLATFORM_JAR) -M AndroidManifest.xml apkbuild

$(lib_so): $(obj)
	$(CC) -o $@ -shared $(obj) $(LDFLAGS)

-include $(dep)

%.arm64.o: %.c
	$(CC) -o $@ $(CFLAGS) -c $<

.PHONY: clean
clean:
	rm -f $(obj) $(lib_so)

.PHONY: cleandep
cleandep:
	rm -f $(dep)

.PHONY: install
install: $(name).apk
	adb install -r $(name).apk

.PHONY: uninstall
uninstall:
	adb uninstall $(pkg)

.PHONY: run
run:
	adb shell am start -n $(pkg)/$(act)

.PHONY: stop
stop:
	adb shell am force-stop $(pkg)