ifdef BUILDDIR
# bit of a hack, but we want to make sure BUILDDIR directory structure
# is correct before any commands
$(if $(findstring n,$(MAKEFLAGS)),, $(shell mkdir -p \
	$(BUILDDIR)/ \
	$(BUILDDIR)/bd \
	$(BUILDDIR)/runners \
	$(BUILDDIR)/tests \
	$(BUILDDIR)/benches))
endif
BUILDDIR ?= .

# overridable target/src/tools/flags/etc
ifneq ($(wildcard test.c main.c),)
TARGET ?= $(BUILDDIR)/lfs
else
TARGET ?= $(BUILDDIR)/liblfs.a
endif


CC       ?= gcc
AR       ?= ar
SIZE     ?= size
CTAGS    ?= ctags
NM       ?= nm
OBJDUMP  ?= objdump
VALGRIND ?= valgrind
GDB		 ?= gdb
PERF	 ?= perf

SRC  ?= $(filter-out $(wildcard *.*.c),$(wildcard *.c))
OBJ  := $(SRC:%.c=$(BUILDDIR)/%.o)
DEP  := $(SRC:%.c=$(BUILDDIR)/%.d)
ASM  := $(SRC:%.c=$(BUILDDIR)/%.s)
CI   := $(SRC:%.c=$(BUILDDIR)/%.ci)
GCDA := $(SRC:%.c=$(BUILDDIR)/%.t.a.gcda)

TESTS ?= $(wildcard tests/*.toml)
TEST_SRC ?= $(SRC) \
		$(filter-out $(wildcard bd/*.*.c),$(wildcard bd/*.c)) \
		runners/test_runner.c
TEST_RUNNER ?= $(BUILDDIR)/runners/test_runner
TEST_TC    := $(TESTS:%.toml=$(BUILDDIR)/%.t.c) \
		$(TEST_SRC:%.c=$(BUILDDIR)/%.t.c)
TEST_TAC   := $(TEST_TC:%.t.c=%.t.a.c)
TEST_OBJ   := $(TEST_TAC:%.t.a.c=%.t.a.o)
TEST_DEP   := $(TEST_TAC:%.t.a.c=%.t.a.d)
TEST_CI	   := $(TEST_TAC:%.t.a.c=%.t.a.ci)
TEST_GCNO  := $(TEST_TAC:%.t.a.c=%.t.a.gcno)
TEST_GCDA  := $(TEST_TAC:%.t.a.c=%.t.a.gcda)
TEST_PERF  := $(TEST_RUNNER:%=%.perf)
TEST_TRACE := $(TEST_RUNNER:%=%.trace)

BENCHES ?= $(wildcard benches/*.toml)
BENCH_SRC ?= $(SRC) \
		$(filter-out $(wildcard bd/*.*.c),$(wildcard bd/*.c)) \
		runners/bench_runner.c
BENCH_RUNNER ?= $(BUILDDIR)/runners/bench_runner
BENCH_BC    := $(BENCHES:%.toml=$(BUILDDIR)/%.b.c) \
		$(BENCH_SRC:%.c=$(BUILDDIR)/%.b.c)
BENCH_BAC   := $(BENCH_BC:%.b.c=%.b.a.c)
BENCH_OBJ   := $(BENCH_BAC:%.b.a.c=%.b.a.o)
BENCH_DEP   := $(BENCH_BAC:%.b.a.c=%.b.a.d)
BENCH_CI    := $(BENCH_BAC:%.b.a.c=%.b.a.ci)
BENCH_GCNO  := $(BENCH_BAC:%.b.a.c=%.b.a.gcno)
BENCH_GCDA  := $(BENCH_BAC:%.b.a.c=%.b.a.gcda)
BENCH_PERF  := $(BENCH_RUNNER:%=%.perf)
BENCH_TRACE := $(BENCH_RUNNER:%=%.trace)

CFLAGS += -fcallgraph-info=su
CFLAGS += -g3
CFLAGS += -I.
CFLAGS += -std=c99 -Wall -Wextra -pedantic
CFLAGS += -ftrack-macro-expansion=0
ifdef DEBUG
CFLAGS += -O0
else
CFLAGS += -Os
endif
ifdef TRACE
CFLAGS += -DLFS_YES_TRACE
endif
ifdef YES_COV
CFLAGS += --coverage
endif
ifdef YES_PERF
CFLAGS += -fno-omit-frame-pointer
endif
ifdef YES_PERFBD
CFLAGS += -fno-omit-frame-pointer
endif

ifdef VERBOSE
CODEFLAGS   += -v
DATAFLAGS   += -v
STACKFLAGS  += -v
STRUCTFLAGS += -v
COVFLAGS    += -v
PERFFLAGS   += -v
PERFBDFLAGS += -v
endif
# forward -j flag
PERFFLAGS   += $(filter -j%,$(MAKEFLAGS))
PERFBDFLAGS += $(filter -j%,$(MAKEFLAGS))
ifneq ($(NM),nm)
CODEFLAGS += --nm-path="$(NM)"
DATAFLAGS += --nm-path="$(NM)"
endif
ifneq ($(OBJDUMP),objdump)
CODEFLAGS   += --objdump-path="$(OBJDUMP)"
DATAFLAGS   += --objdump-path="$(OBJDUMP)"
STRUCTFLAGS += --objdump-path="$(OBJDUMP)"
PERFFLAGS   += --objdump-path="$(OBJDUMP)"
PERFBDFLAGS += --objdump-path="$(OBJDUMP)"
endif
ifneq ($(PERF),perf)
PERFFLAGS += --perf-path="$(PERF)"
endif

TESTFLAGS  += -b
BENCHFLAGS += -b
# forward -j flag
TESTFLAGS  += $(filter -j%,$(MAKEFLAGS))
BENCHFLAGS += $(filter -j%,$(MAKEFLAGS))
ifdef YES_PERF
TESTFLAGS  += -p$(TEST_PERF)
BENCHFLAGS += -p$(BENCH_PERF)
endif
ifdef YES_PERFBD
TESTFLAGS += -t$(TEST_TRACE) --trace-backtrace --trace-freq=100
endif
ifndef NO_PERFBD
BENCHFLAGS += -t$(BENCH_TRACE) --trace-backtrace --trace-freq=100
endif
ifdef VERBOSE
TESTFLAGS   += -v
TESTCFLAGS  += -v
BENCHFLAGS  += -v
BENCHCFLAGS += -v
endif
ifdef EXEC
TESTFLAGS  += --exec="$(EXEC)"
BENCHFLAGS += --exec="$(EXEC)"
endif
ifneq ($(GDB),gdb)
TESTFLAGS  += --gdb-path="$(GDB)"
BENCHFLAGS += --gdb-path="$(GDB)"
endif
ifneq ($(VALGRIND),valgrind)
TESTFLAGS  += --valgrind-path="$(VALGRIND)"
BENCHFLAGS += --valgrind-path="$(VALGRIND)"
endif
ifneq ($(PERF),perf)
TESTFLAGS  += --perf-path="$(PERF)"
BENCHFLAGS += --perf-path="$(PERF)"
endif


# commands

## Build littlefs
.PHONY: all build
all build: $(TARGET)

## Build assembly files
.PHONY: asm
asm: $(ASM)

## Find the total size
.PHONY: size
size: $(OBJ)
	$(SIZE) -t $^

## Generate a ctags file
.PHONY: tags
tags:
	$(CTAGS) --totals --c-types=+p $(shell find -H -name '*.h') $(SRC)

## Show this help text
.PHONY: help
help:
	@$(strip awk '/^## / { \
			sub(/^## /,""); \
			getline rule; \
			while (rule ~ /^(#|\.PHONY|ifdef|ifndef)/) getline rule; \
			gsub(/:.*/, "", rule); \
			printf " "" %-25s %s\n", rule, $$0 \
		}' $(MAKEFILE_LIST))

## Build the test-runner
.PHONY: test-runner build-test
ifndef NO_COV
test-runner build-test: CFLAGS+=--coverage
endif
ifdef YES_PERF
test-runner build-test: CFLAGS+=-fno-omit-frame-pointer
endif
ifdef YES_PERFBD
test-runner build-test: CFLAGS+=-fno-omit-frame-pointer
endif
# note we remove some binary dependent files during compilation,
# otherwise it's way to easy to end up with outdated results
test-runner build-test: $(TEST_RUNNER)
ifndef NO_COV
	rm -f $(TEST_GCDA)
endif
ifdef YES_PERF
	rm -f $(TEST_PERF)
endif
ifdef YES_PERFBD
	rm -f $(TEST_TRACE)
endif

## Run the tests, -j enables parallel tests
.PHONY: test
test: test-runner
	./scripts/test.py $(TEST_RUNNER) $(TESTFLAGS)

## List the tests
.PHONY: test-list
test-list: test-runner
	./scripts/test.py $(TEST_RUNNER) $(TESTFLAGS) -l

## Build the bench-runner
.PHONY: bench-runner build-bench
ifdef YES_COV
bench-runner build-bench: CFLAGS+=--coverage
endif
ifdef YES_PERF
bench-runner build-bench: CFLAGS+=-fno-omit-frame-pointer
endif
ifndef NO_PERFBD
bench-runner build-bench: CFLAGS+=-fno-omit-frame-pointer
endif
# note we remove some binary dependent files during compilation,
# otherwise it's way to easy to end up with outdated results
bench-runner build-bench: $(BENCH_RUNNER)
ifdef YES_COV 
	rm -f $(BENCH_GCDA)
endif
ifdef YES_PERF
	rm -f $(BENCH_PERF)
endif
ifndef NO_PERFBD
	rm -f $(BENCH_TRACE)
endif

## Run the benchmarks, -j enables parallel benchmarks
.PHONY: bench
bench: bench-runner
	./scripts/bench.py $(BENCH_RUNNER) $(BENCHFLAGS)

## List the benchmarks
.PHONY: bench-list
bench-list: bench-runner
	./scripts/bench.py $(BENCH_RUNNER) $(BENCHFLAGS) -l

## Find the per-function code size
.PHONY: code
code: $(OBJ)
	./scripts/code.py $^ -Ssize $(CODEFLAGS)

## Find the per-function data size
.PHONY: data
data: $(OBJ)
	./scripts/data.py $^ -Ssize $(DATAFLAGS)

## Find the per-function stack usage
.PHONY: stack
stack: $(CI)
	./scripts/stack.py $^ -Slimit -Sframe $(STACKFLAGS)

## Find the struct sizes
.PHONY: struct
struct: $(OBJ)
	./scripts/struct_.py $^ -Ssize $(STRUCTFLAGS)

## Find the line/branch coverage after a test run
.PHONY: cov
cov: $(GCDA)
	$(strip ./scripts/cov.py \
		$^ $(patsubst %,-F%,$(SRC)) \
		-slines -sbranches \
		$(COVFLAGS))

## Find the perf results after bench run with YES_PERF
.PHONY: perf
perf: $(BENCH_PERF)
	$(strip ./scripts/perf.py \
		$^ $(patsubst %,-F%,$(SRC)) \
		-Scycles \
		$(PERFFLAGS))

## Find the perfbd results after a bench run
.PHONY: perfbd
perfbd: $(BENCH_TRACE)
	$(strip ./scripts/perfbd.py \
		$(BENCH_RUNNER) $^ $(patsubst %,-F%,$(SRC)) \
		-Serased -Sproged -Sreaded \
		$(PERFBDFLAGS))

## Find a summary of compile-time sizes
.PHONY: summary sizes
summary sizes: $(BUILDDIR)/lfs.csv
	$(strip ./scripts/summary.py -Y $^ \
		-fcode=code_size \
		-fdata=data_size \
		-fstack=stack_limit \
		-fstruct=struct_size \
		--max=stack \
		$(SUMMARYFLAGS))


# rules
-include $(DEP)
-include $(TEST_DEP)
.SUFFIXES:
.SECONDARY:

$(BUILDDIR)/lfs: $(OBJ)
	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@

$(BUILDDIR)/liblfs.a: $(OBJ)
	$(AR) rcs $@ $^

$(BUILDDIR)/lfs.code.csv: $(OBJ)
	./scripts/code.py $^ -q $(CODEFLAGS) -o $@

$(BUILDDIR)/lfs.data.csv: $(OBJ)
	./scripts/data.py $^ -q $(CODEFLAGS) -o $@

$(BUILDDIR)/lfs.stack.csv: $(CI)
	./scripts/stack.py $^ -q $(CODEFLAGS) -o $@

$(BUILDDIR)/lfs.struct.csv: $(OBJ)
	./scripts/struct_.py $^ -q $(CODEFLAGS) -o $@

$(BUILDDIR)/lfs.cov.csv: $(GCDA)
	./scripts/cov.py $^ $(patsubst %,-F%,$(SRC)) -q $(COVFLAGS) -o $@

$(BUILDDIR)/lfs.perf.csv: $(BENCH_PERF)
	./scripts/perf.py $^ $(patsubst %,-F%,$(SRC)) -q $(PERFFLAGS) -o $@

$(BUILDDIR)/lfs.perfbd.csv: $(BENCH_TRACE)
	$(strip ./scripts/perfbd.py \
		$(BENCH_RUNNER) $^ $(patsubst %,-F%,$(SRC)) \
		-q $(PERFBDFLAGS) -o $@)

$(BUILDDIR)/lfs.csv: \
		$(BUILDDIR)/lfs.code.csv \
		$(BUILDDIR)/lfs.data.csv \
		$(BUILDDIR)/lfs.stack.csv \
		$(BUILDDIR)/lfs.struct.csv
	./scripts/summary.py $^ -q $(SUMMARYFLAGS) -o $@

$(BUILDDIR)/runners/test_runner: $(TEST_OBJ)
	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@

$(BUILDDIR)/runners/bench_runner: $(BENCH_OBJ)
	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@

# our main build rule generates .o, .d, and .ci files, the latter
# used for stack analysis
$(BUILDDIR)/%.o $(BUILDDIR)/%.ci: %.c
	$(CC) -c -MMD $(CFLAGS) $< -o $(BUILDDIR)/$*.o

$(BUILDDIR)/%.s: %.c
	$(CC) -S $(CFLAGS) $< -o $@

$(BUILDDIR)/%.a.c: %.c
	./scripts/prettyasserts.py -p LFS_ASSERT $< -o $@

$(BUILDDIR)/%.a.c: $(BUILDDIR)/%.c
	./scripts/prettyasserts.py -p LFS_ASSERT $< -o $@

$(BUILDDIR)/%.t.c: %.toml
	./scripts/test.py -c $< $(TESTCFLAGS) -o $@

$(BUILDDIR)/%.t.c: %.c $(TESTS)
	./scripts/test.py -c $(TESTS) -s $< $(TESTCFLAGS) -o $@

$(BUILDDIR)/%.b.c: %.toml
	./scripts/bench.py -c $< $(BENCHCFLAGS) -o $@

$(BUILDDIR)/%.b.c: %.c $(BENCHES)
	./scripts/bench.py -c $(BENCHES) -s $< $(BENCHCFLAGS) -o $@

## Clean everything
.PHONY: clean
clean:
	rm -f $(BUILDDIR)/lfs
	rm -f $(BUILDDIR)/liblfs.a
	$(strip rm -f \
		$(BUILDDIR)/lfs.csv \
		$(BUILDDIR)/lfs.code.csv \
		$(BUILDDIR)/lfs.data.csv \
		$(BUILDDIR)/lfs.stack.csv \
		$(BUILDDIR)/lfs.struct.csv \
		$(BUILDDIR)/lfs.cov.csv \
		$(BUILDDIR)/lfs.perf.csv \
		$(BUILDDIR)/lfs.perfbd.csv)
	rm -f $(OBJ)
	rm -f $(DEP)
	rm -f $(ASM)
	rm -f $(CI)
	rm -f $(TEST_RUNNER)
	rm -f $(TEST_TC)
	rm -f $(TEST_TAC)
	rm -f $(TEST_OBJ)
	rm -f $(TEST_DEP)
	rm -f $(TEST_CI)
	rm -f $(TEST_GCNO)
	rm -f $(TEST_GCDA)
	rm -f $(TEST_PERF)
	rm -f $(TEST_TRACE)
	rm -f $(BENCH_RUNNER)
	rm -f $(BENCH_BC)
	rm -f $(BENCH_BAC)
	rm -f $(BENCH_OBJ)
	rm -f $(BENCH_DEP)
	rm -f $(BENCH_CI)
	rm -f $(BENCH_GCNO)
	rm -f $(BENCH_GCDA)
	rm -f $(BENCH_PERF)
	rm -f $(BENCH_TRACE)