#### PROJECT SETTINGS ####
# The name of the executable to be created
BIN_NAME := howm
# Compiler used
CC ?= gcc
# Extension of source files used in the project
SRC_EXT = c
# Path to the source directory, relative to the makefile
SRC_PATH = src
# General compiler flags
COMPILE_FLAGS ?= -std=c99 -Wall -Wextra
# Additional release-specific flags
RCOMPILE_FLAGS = -D NDEBUG
# Additional debug-specific flags
DCOMPILE_FLAGS = -g3
# Add additional include paths
INCLUDES = -I $(SRC_PATH)/
# General linker settings
LINK_FLAGS = -lxcb -lxcb-icccm -lxcb-ewmh -lxcb-randr
# Additional release-specific linker settings
RLINK_FLAGS =
# Additional debug-specific linker settings
DLINK_FLAGS =
# Destination directory, like a jail or mounted system
DESTDIR = /
# Install path (bin/ is appended automatically)
INSTALL_PREFIX = usr
# Xsession entries path
XSESSION_PREFIX = usr/share
#### END PROJECT SETTINGS ####

# Generally should not need to edit below this line

# Verbose option, to output compile and link commands
export V = false
export CMD_PREFIX = @
ifeq ($(V),true)
	CMD_PREFIX =
endif

# Combine compiler and linker flags
release: export CCFLAGS := $(CCFLAGS) $(COMPILE_FLAGS) $(RCOMPILE_FLAGS)
release: export LDFLAGS := $(LDFLAGS) $(LINK_FLAGS) $(RLINK_FLAGS)
debug: export CCFLAGS := $(CCFLAGS) $(COMPILE_FLAGS) $(DCOMPILE_FLAGS)
debug: export LDFLAGS := $(LDFLAGS) $(LINK_FLAGS) $(DLINK_FLAGS)

# Build and output paths
release: export BUILD_PATH := build/release
release: export BIN_PATH := bin/release
debug: export BUILD_PATH := build/debug
debug: export BIN_PATH := bin/debug
install: export BIN_PATH := bin/release

# Find all source files in the source directory
SOURCES = $(shell find $(SRC_PATH)/ -name '*.$(SRC_EXT)')
# Set the object file names, with the source directory stripped
# from the path, and the build path prepended in its place
OBJECTS = $(SOURCES:$(SRC_PATH)/%.$(SRC_EXT)=$(BUILD_PATH)/%.o)
# Set the dependency files that will be used to add header dependencies
DEPS = $(OBJECTS:.o=.d)

# Macros for timing compilation
TIME_FILE = $(dir $@).$(notdir $@)_time
START_TIME = date '+%s' > $(TIME_FILE)
END_TIME = read st < $(TIME_FILE) ; \
	$(RM) $(TIME_FILE) ; \
	st=$$((`date '+%s'` - $$st - 86400)) ; \
	echo `date -u -d @$$st '+%H:%M:%S'`

# Version macros
# Comment/remove this section to remove versioning
VERSION := $(shell git describe --tags --long --dirty --always | \
	sed 's/v\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)-\?.*-\([0-9]*\)-\(.*\)/\1 \2 \3 \4 \5/g')
VERSION_MAJOR := $(word 1, $(VERSION))
VERSION_MINOR := $(word 2, $(VERSION))
VERSION_PATCH := $(word 3, $(VERSION))
VERSION_REVISION := $(word 4, $(VERSION))
VERSION_HASH := $(word 5, $(VERSION))
VERSION_STRING := \
	"$(VERSION_MAJOR).$(VERSION_MINOR).$(VERSION_PATCH).$(VERSION_REVISION)"
override CCFLAGS := $(CCFLAGS) \
	-D VERSION_MAJOR=$(VERSION_MAJOR) \
	-D VERSION_MINOR=$(VERSION_MINOR) \
	-D VERSION_PATCH=$(VERSION_PATCH) \
	-D VERSION_REVISION=$(VERSION_REVISION) \
	-D VERSION_HASH=\"$(VERSION_HASH)\"

# Standard, non-optimized release build
.PHONY: release
release: dirs
	@echo "Beginning release build v$(VERSION_STRING)"
	@$(START_TIME)
	@$(MAKE) all --no-print-directory
	@echo -n "Total build time: "
	@$(END_TIME)

# Debug build for gdb debugging
.PHONY: debug
debug: dirs
	@echo "Beginning debug build v$(VERSION_STRING)"
	@$(START_TIME)
	@$(MAKE) all --no-print-directory
	@echo -n "Total build time: "
	@$(END_TIME)

# Create the directories used in the build
.PHONY: dirs
dirs:
	@echo "Creating directories"
	@mkdir -p $(dir $(OBJECTS))
	@mkdir -p $(BIN_PATH)

# Installs to the set path
.PHONY: install
install:
	@echo "Installing to $(DESTDIR)$(INSTALL_PREFIX)/bin"
	@install -m 0755 $(BIN_PATH)/$(BIN_NAME) $(DESTDIR)$(INSTALL_PREFIX)/bin
	@install -d -m 0755 $(DESTDIR)$(XSESSION_PREFIX)/xsessions
	@install -m 0644 howm.xsession.desktop $(DESTDIR)$(XSESSION_PREFIX)/xsessions/howm.desktop

.PHONY: check
check:
	@echo "Using checkpatch.pl to check style."
	@./checkpatch.pl --no-tree --ignore LONG_LINE,NEW_TYPEDEFS,UNNECESSARY_ELSE,MACRO_WITH_FLOW_CONTROL,GLOBAL_INITIALISERS -f src/*.c
	@./checkpatch.pl --no-tree --ignore LONG_LINE,NEW_TYPEDEFS,UNNECESSARY_ELSE,MACRO_WITH_FLOW_CONTROL,GLOBAL_INITIALISERS -f src/*.h
	
.PHONY: analyse
analyse:
	@echo "Running scan-build to look for bugs."
	@scan-build -v -o analyse make clean debug

# Removes all build files
.PHONY: clean
clean:
	@echo "Deleting $(BIN_NAME) symlink"
	@$(RM) $(BIN_NAME)
	@echo "Deleting directories"
	@$(RM) -r build
	@$(RM) -r bin
	@$(RM) -r analyse

# Main rule, checks the executable and symlinks to the output
all: $(BIN_PATH)/$(BIN_NAME)
	@echo "Making symlink: $(BIN_NAME) -> $<"
	@$(RM) $(BIN_NAME)
	@ln -s $(BIN_PATH)/$(BIN_NAME) $(BIN_NAME)

# Link the executable
$(BIN_PATH)/$(BIN_NAME): $(OBJECTS)
	@echo "Linking: $@"
	@$(START_TIME)
	$(CMD_PREFIX)$(CC) $(OBJECTS) $(LDFLAGS) -o $@
	@echo -en "\t Link time: "
	@$(END_TIME)

# Add dependency files, if they exist
-include $(DEPS)

# Source file rules
# After the first compilation they will be joined with the rules from the
# dependency files to provide header dependencies
$(BUILD_PATH)/%.o: $(SRC_PATH)/%.$(SRC_EXT)
	@echo "Compiling: $< -> $@"
	@$(START_TIME)
	$(CMD_PREFIX)$(CC) $(CCFLAGS) $(INCLUDES) -MP -MMD -c $< -o $@
	@echo -en "\t Compile time: "
	@$(END_TIME)
