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

BUILD_BASE  = build
FW_BASE     = firmware

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

# base directory of the ESP8266 SDK package, absolute
SDK_BASE    ?= /home/ed/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

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

# 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

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

# linker script used for the above linkier step
LD_SCRIPT   = eagle.app.v6.ld

# 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
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))
OBJ     := $(patsubst %.c,$(BUILD_BASE)/%.o,$(SRC))
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)

define compile-objects
$1/%.o: %.c
    $(vecho) "CC $$<"
    $(Q) $(CC) $(INCDIR) $(MODULE_INCDIR) $(EXTRA_INCDIR) $(SDK_INCDIR) $(CFLAGS) -c $$< -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)

$(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 $@ $^

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)

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