VERSION    := 0.2.0

ifeq ($(origin FC),default)
FC         := gfortran
endif
FC         ?= gfortran
CC         ?= cc
AR         ?= ar
FPRETTIFY  ?= fprettify
PREFIX     ?= /usr/local
LIBDIR     ?= $(PREFIX)/lib
INCLUDEDIR ?= $(PREFIX)/include/cepis
BINDIR     ?= $(PREFIX)/bin

BUILD      := build

CURL_CFLAGS := $(shell pkg-config --cflags libcurl 2>/dev/null)
CURL_LIBS   := $(shell pkg-config --libs libcurl 2>/dev/null || echo -lcurl)

WARNINGS   := -Wall -Wextra -Wno-unused-dummy-argument
SAN        := -fsanitize=address,undefined -fno-omit-frame-pointer
FFLAGS     ?= -O2 -g
FFLAGS     += -std=f2018 -fimplicit-none -J$(BUILD) -I$(BUILD) $(WARNINGS) $(EXTRA_FFLAGS)
CFLAGS     ?= -O2 -g
CFLAGS     += -std=c11 -D_POSIX_C_SOURCE=200809L -Wall -Wextra $(EXTRA_CFLAGS)
LDFLAGS    += $(EXTRA_LDFLAGS)
LDLIBS     += $(CURL_LIBS)

LIB_SRC    := src/cepis_errors.f90 src/cepis_strings.f90 src/cepis_json.f90 \
              src/cepis_csv.f90 src/cepis_http.f90 src/cepis_models.f90 \
              src/cepis.f90
LIB_OBJ    := $(LIB_SRC:%.f90=$(BUILD)/%.o)
LIB_MOD    := $(BUILD)/cepis.mod $(BUILD)/cepis_errors.mod \
              $(BUILD)/cepis_strings.mod $(BUILD)/cepis_json.mod \
              $(BUILD)/cepis_csv.mod $(BUILD)/cepis_http.mod \
              $(BUILD)/cepis_models.mod

ALL_F90    := $(LIB_SRC) test/test_server.f90 app/main.f90 test/test_cepis.f90

STATIC     := $(BUILD)/libcepis.a
CLI        := $(BUILD)/cepis
TESTS      := $(BUILD)/test_cepis

.DEFAULT_GOAL := help
.PHONY: help build test lint format check sanitize clean install uninstall

help:
	@echo 'Targets:'
	@echo '  build      static library, modules and the cepis CLI'
	@echo '  test       build and run the suite against a local HTTP server'
	@echo '  lint       strict warning-free rebuild + fprettify --diff (read-only)'
	@echo '  format     apply fprettify (writes)'
	@echo '  check      lint, then test, then build'
	@echo '  sanitize   rebuild and run the suite under ASan + UBSan'
	@echo '  install    install modules, the library and the CLI under PREFIX'
	@echo '  clean      remove $(BUILD)/'
	@echo
	@echo 'Requires gfortran (or another Fortran 2018 compiler), a C compiler'
	@echo 'and libcurl with its development headers.'
	@echo 'Override the compiler with e.g. make test FC=flang'

build: $(STATIC) $(CLI)

$(BUILD)/%.o: %.f90
	@mkdir -p $(dir $@) $(BUILD)
	$(FC) $(FFLAGS) -c $< -o $@

$(BUILD)/%.o: %.c
	@mkdir -p $(dir $@)
	$(CC) $(CFLAGS) $(CURL_CFLAGS) -c $< -o $@

$(BUILD)/src/cepis_json.o:    $(BUILD)/src/cepis_strings.o
$(BUILD)/src/cepis_csv.o:     $(BUILD)/src/cepis_strings.o
$(BUILD)/src/cepis_http.o:    $(BUILD)/src/cepis_strings.o
$(BUILD)/src/cepis_models.o:  $(BUILD)/src/cepis_json.o $(BUILD)/src/cepis_strings.o
$(BUILD)/src/cepis.o:         $(BUILD)/src/cepis_errors.o $(BUILD)/src/cepis_strings.o \
                              $(BUILD)/src/cepis_json.o $(BUILD)/src/cepis_csv.o \
                              $(BUILD)/src/cepis_http.o $(BUILD)/src/cepis_models.o
$(BUILD)/app/main.o:          $(BUILD)/src/cepis.o
$(BUILD)/test/test_server.o:  $(BUILD)/src/cepis_strings.o
$(BUILD)/test/test_cepis.o:   $(BUILD)/src/cepis.o $(BUILD)/test/test_server.o

$(STATIC): $(LIB_OBJ)
	@mkdir -p $(dir $@)
	$(AR) rcs $@ $(LIB_OBJ)

$(CLI): $(BUILD)/app/main.o $(STATIC)
	$(FC) $(FFLAGS) $(BUILD)/app/main.o $(STATIC) $(LDFLAGS) $(LDLIBS) -o $@

$(TESTS): $(BUILD)/test/test_cepis.o $(BUILD)/test/test_server.o \
          $(BUILD)/test/http_server.o $(STATIC)
	$(FC) $(FFLAGS) $(BUILD)/test/test_cepis.o $(BUILD)/test/test_server.o \
		$(BUILD)/test/http_server.o $(STATIC) $(LDFLAGS) $(LDLIBS) -lpthread -o $@

test: $(TESTS)
	$(TESTS)

# Read-only by design, so it is safe in CI and in a pre-commit hook. The
# rebuild turns every warning into an error without touching the ordinary
# build tree; fprettify only reports, and is skipped when it is not installed.
lint:
	@rm -rf $(BUILD)/lint
	@mkdir -p $(BUILD)/lint
	$(FC) -std=f2018 -fimplicit-none $(WARNINGS) -Werror -fsyntax-only \
		-J$(BUILD)/lint -I$(BUILD)/lint $(ALL_F90)
	$(CC) $(CFLAGS) $(CURL_CFLAGS) -Werror -fsyntax-only test/http_server.c
	@if command -v $(FPRETTIFY) >/dev/null 2>&1; then \
		$(FPRETTIFY) --diff --indent 4 --line-length 100 $(ALL_F90); \
	else \
		echo 'fprettify not installed: skipping style check'; \
	fi

format:
	$(FPRETTIFY) --indent 4 --line-length 100 $(ALL_F90)

# The order matters: lint is the fastest to fail, build the slowest, so a
# broken run reports the cheapest problem first.
check: lint test build

# Rebuilt from scratch: the sanitizers change the ABI of the objects, so they
# must not be mixed with objects from an ordinary build.
sanitize:
	$(MAKE) clean
	$(MAKE) test EXTRA_FFLAGS='$(SAN) -fcheck=all' EXTRA_CFLAGS='$(SAN)' \
		EXTRA_LDFLAGS='$(SAN)'
	$(MAKE) clean

install: build
	install -d $(DESTDIR)$(INCLUDEDIR) $(DESTDIR)$(LIBDIR) $(DESTDIR)$(BINDIR)
	install -m 644 $(LIB_MOD) $(DESTDIR)$(INCLUDEDIR)/
	install -m 644 $(STATIC) $(DESTDIR)$(LIBDIR)/
	install -m 755 $(CLI) $(DESTDIR)$(BINDIR)/

uninstall:
	rm -rf $(DESTDIR)$(INCLUDEDIR)
	rm -f $(DESTDIR)$(LIBDIR)/libcepis.a
	rm -f $(DESTDIR)$(BINDIR)/cepis

clean:
	rm -rf $(BUILD)