# Copyright © Tavian Barnes <tavianator@tavianator.com>
# SPDX-License-Identifier: 0BSD

# Makefile that implements `./configure`

include build/prelude.mk
include build/exports.mk

# All configuration steps
config: gen/config.mk gen/config.h
.PHONY: config

# Makefile fragments generated by `./configure`
MKS := \
    gen/vars.mk \
    gen/flags.mk \
    gen/deps.mk \
    gen/pkgs.mk

# The main configuration file, which includes the others
gen/config.mk: ${MKS}
	${MSG} "[ GEN] $@"
	@printf '# %s\n' "$@" >$@
	@printf 'include %s\n' ${.ALLSRC} >>$@
	${VCAT} gen/config.mk
.PHONY: gen/config.mk

# Saves the configurable variables
gen/vars.mk::
	@${MKDIR} ${@D}
	${MSG} "[ GEN] $@"
	@printf '# %s\n' "$@" >$@
	@printf 'PREFIX := %s\n' "$$XPREFIX" >>$@
	@printf 'MANDIR := %s\n' "$$XMANDIR" >>$@
	@printf 'OS := %s\n' "$${OS:-$$(uname)}" >>$@
	@printf 'CC := %s\n' "$$XCC" >>$@
	@printf 'INSTALL := %s\n' "$$XINSTALL" >>$@
	@printf 'MKDIR := %s\n' "$$XMKDIR" >>$@
	@printf 'PKG_CONFIG := %s\n' "$$XPKG_CONFIG" >>$@
	@printf 'RM := %s\n' "$$XRM" >>$@
	${VCAT} $@

# Sets the build flags.  This depends on vars.mk and uses a recursive make so
# that the default flags can depend on variables like ${OS}.
gen/flags.mk: gen/vars.mk
	@+XMAKEFLAGS="$$MAKEFLAGS" ${MAKE} -sf build/flags.mk $@
.PHONY: gen/flags.mk

# Check for dependency generation support
gen/deps.mk: gen/flags.mk
	@+XMAKEFLAGS="$$MAKEFLAGS" ${MAKE} -sf build/deps.mk $@
.PHONY: gen/deps.mk

# Auto-detect dependencies and their build flags
gen/pkgs.mk: gen/flags.mk
	@+XMAKEFLAGS="$$MAKEFLAGS" ${MAKE} -sf build/pkgs.mk $@
.PHONY: gen/pkgs.mk

# Compile-time feature detection
gen/config.h: gen/config.mk
	@+XMAKEFLAGS="$$MAKEFLAGS" ${MAKE} -sf build/header.mk $@
.PHONY: gen/config.h