# Makefile based on https://github.com/esp8266/source-code-examples/blob/master/example.Makefile

# C++ adjustment: https://gist.github.com/jcmvbkbc/795b51494aea52bf2d1e

# adjust the PATH variable [needed e.g. for esptool.py
export PATH :=	/apps/esp/esp-open-sdk/xtensa-lx106-elf/bin:$(PATH)

ROOT		= /apps/esp/esp-open-sdk/sdk
BUILD_BASE	= build
FW_BASE		= firmware

# base directory for the compiler
XTENSA_TOOLS_ROOT ?= /apps/esp/esp-open-sdk/xtensa-lx106-elf/bin

# base directory of the ESP8266 SDK package, absolute
SDK_BASE	?= /apps/esp/esp-open-sdk/sdk

# esptool.py path and port
ESPTOOL		?= esptool.py
ESPPORT		?= /dev/ttyUSB0

# name for the target project
TARGET		= app

# which modules (subdirectories) of the project to include in compiling
MODULES		= driver user
EXTRA_INCDIR    = include $(ROOT)/include/ $(ROOT)/driver_lib/include/ /apps/

# libraries used in this project, mainly provided by the SDK
#LIBS		= c gcc hal pp phy net80211 lwip wpa wpa2 crypto main 
#LIBS		= c gcc pp phy net80211 lwip wpa main 
LIBS		= c gcc hal phy pp net80211 lwip wpa main wps crypto m

# compiler flags using during compilation of source files
#CFLAGS		= -Os -g -O2 -Wpointer-arith -Wundef -Werror -Wl,-EL -fno-inline-functions -nostdlib -mlongcalls -mtext-section-literals  -D__ets__ -DICACHE_FLASH
CFLAGS		= -Os -Wpointer-arith -Wall -Wextra -Wundef -Werror=return-type -Wl,-EL  -fno-inline-functions -nostdlib -mlongcalls -mtext-section-literals  -D__ets__ -DICACHE_FLASH 
CXXFLAGS	= $(CFLAGS) -fno-rtti -fno-exceptions -std=c++11

# linker flags used to generate the main object file
LDFLAGS		= -nostdlib -Wl,--no-check-sections -Wl,--gc-sections -u call_user_start -Wl,-static

# linker script used for the above linkier step
LD_SCRIPT	= eagle.app.v6.ld
#LD_SCRIPT	= eagle.app.v6.modified.ld
#http://www.esp8266.com/viewtopic.php?f=9&t=478&start=8

# various paths from the SDK used in this project
SDK_LIBDIR	= lib
SDK_LDDIR	= ld
SDK_INCDIR	= include include/json examples/driver_lib/include/driver

# we create two different files for uploading into the flash
# these are the names and options to generate them
FW_FILE_1_ADDR	:= 0x00000
FW_FILE_2_ADDR	:= 0x10000

# select which tools to use as compiler, librarian and linker
CC		:= $(XTENSA_TOOLS_ROOT)/xtensa-lx106-elf-gcc
CXX		:= $(XTENSA_TOOLS_ROOT)/xtensa-lx106-elf-g++
AR		:= $(XTENSA_TOOLS_ROOT)/xtensa-lx106-elf-ar
LD		:= $(XTENSA_TOOLS_ROOT)/xtensa-lx106-elf-gcc

####
#### no user configurable options below here
####
SRC_DIR		:= $(MODULES)
BUILD_DIR	:= $(addprefix $(BUILD_BASE)/,$(MODULES))

SDK_LIBDIR	:= $(addprefix $(SDK_BASE)/,$(SDK_LIBDIR))
SDK_INCDIR	:= $(addprefix -I$(SDK_BASE)/,$(SDK_INCDIR))

SRC		:= $(foreach sdir,$(SRC_DIR),$(wildcard $(sdir)/*.c*))

C_OBJ		:= $(patsubst %.c,%.o,$(SRC))
CXX_OBJ		:= $(patsubst %.cpp,%.o,$(C_OBJ))
OBJ		:= $(patsubst %.o,$(BUILD_BASE)/%.o,$(CXX_OBJ))

LIBS		:= $(addprefix -l,$(LIBS))
APP_AR		:= $(addprefix $(BUILD_BASE)/,$(TARGET)_app.a)
TARGET_OUT	:= $(addprefix $(BUILD_BASE)/,$(TARGET).out)

LD_SCRIPT	:= $(addprefix -T$(SDK_BASE)/$(SDK_LDDIR)/,$(LD_SCRIPT))

INCDIR		:= $(addprefix -I,$(SRC_DIR))
EXTRA_INCDIR	:= $(addprefix -I,$(EXTRA_INCDIR))
MODULE_INCDIR	:= $(addsuffix /include,$(INCDIR))

FW_FILE_1	:= $(addprefix $(FW_BASE)/,$(FW_FILE_1_ADDR).bin)
FW_FILE_2	:= $(addprefix $(FW_BASE)/,$(FW_FILE_2_ADDR).bin)

V ?= $(VERBOSE)
ifeq ("$(V)","1")
Q :=
vecho := @true
else
Q := @
vecho := @echo
endif

vpath %.c $(SRC_DIR)
vpath %.cpp $(SRC_DIR)

define compile-objects
$1/%.o: %.c
	$(vecho) "CC $$<"
	$(Q) $(CC) $(INCDIR) $(MODULE_INCDIR) $(EXTRA_INCDIR) $(SDK_INCDIR) $(CFLAGS) -c $$< -o $$@
$1/%.o: $(wildcard **/*.cpp)
	$(vecho) "C+ $$<"
	$(Q) $(CXX) $(INCDIR) $(MODULE_INCDIR) $(EXTRA_INCDIR) $(SDK_INCDIR) $(CXXFLAGS) -c $$< -o $$@
endef

.PHONY: all checkdirs flash clean

all: checkdirs $(TARGET_OUT) $(FW_FILE_1) $(FW_FILE_2)

$(FW_BASE)/%.bin: $(TARGET_OUT) | $(FW_BASE)
	$(vecho) "FW $(FW_BASE)/"
	$(Q) $(ESPTOOL) elf2image -o $(FW_BASE)/ $(TARGET_OUT)
	$(Q) echo ""
	$(Q) echo "final firmware:"
	$(Q) ls -l firmware/*.bin
	$(Q) xtensa-lx106-elf-size --format=sysv $(TARGET_OUT)

$(TARGET_OUT): $(APP_AR)
	$(vecho) "LD $@"
	$(Q) $(LD) -L$(SDK_LIBDIR) $(LD_SCRIPT) $(LDFLAGS) -Wl,--start-group $(LIBS) $(APP_AR) -Wl,--end-group -o $@

$(APP_AR): $(OBJ)
	$(vecho) "AR $@"
	$(Q) $(AR) cru $@ $^
	$(Q) echo ""
	$(Q) echo "custom code size:"
	$(Q) ls -l build/app_app.a
	
checkdirs: $(BUILD_DIR) $(FW_BASE)

$(BUILD_DIR):
	$(Q) mkdir -p $@

$(FW_BASE):
	$(Q) mkdir -p $@

flash: $(FW_FILE_1) $(FW_FILE_2)
	$(ESPTOOL) --port $(ESPPORT) write_flash $(FW_FILE_1_ADDR) $(FW_FILE_1) $(FW_FILE_2_ADDR) $(FW_FILE_2)

clean:
	$(Q) rm -rf $(FW_BASE) $(BUILD_BASE)
	
	
# note: each new ESP2866 has to be initialized once!
# the memory addresses for those files, depend on the flash size
# below it is configured for 32mbit flash [4096kb]
# see: https://espressif.com/en/support/explore/get-started/esp8266/getting-started-guidek	
init:
	$(ESPTOOL) --port $(ESPPORT) write_flash 0x3FC000 $(ROOT)/bin/esp_init_data_default.bin 0x3FE000 $(ROOT)/bin/blank.bin

$(foreach bdir,$(BUILD_DIR),$(eval $(call compile-objects,$(bdir))))