# ---------------------------------------------------------------------------
# Compiler and Base Flags
# ---------------------------------------------------------------------------
CXX := g++

# Common flags (for both Debug and Release)
CXXFLAGS_BASE := -Wall -Wextra -std=c++17

# Debug flags (includes TIMERS and DEBUG, plus -g)
CXXFLAGS_DEBUG := $(CXXFLAGS_BASE) -g -DDEBUG -DTIMERS

# Release flags (optimized, no debug macros, no timers)
CXXFLAGS_RELEASE := $(CXXFLAGS_BASE) -O2 -DNDEBUG

# By default, we build in Debug mode:
BUILD_TYPE ?= debug

# We’ll dynamically set BUILD_DIR and CXXFLAGS based on BUILD_TYPE
ifeq ($(BUILD_TYPE),debug)
    BUILD_DIR := build
    CXXFLAGS := $(CXXFLAGS_DEBUG)
else ifeq ($(BUILD_TYPE),release)
    BUILD_DIR := release
    CXXFLAGS := $(CXXFLAGS_RELEASE)
else
    $(error Unknown BUILD_TYPE '$(BUILD_TYPE)'. Valid options: debug or release)
endif

# ---------------------------------------------------------------------------
# Detect Platform
# ---------------------------------------------------------------------------
ifeq ($(OS),Windows_NT)
    # -------------------- Windows --------------------
    EXE_EXT := .exe

    # Example paths (adjust if you have your libs somewhere else):
    GLFW_INCLUDE := C:/libs/glfw/include
    GLEW_INCLUDE := C:/libs/glew/include

    LIB_PATHS := -LC:/libs/glfw/lib \
                 -LC:/libs/glew/lib \
                 -Llib

    LIBS := -lglfw3 -lopengl32 -lgdi32 -limm32 -lole32 -loleaut32 -luuid \
            -lwinmm -lglew32 -lglu32 -lyaml-cpp -llua54

    define MKDIR_P
        if not exist "$(1)" mkdir "$(1)" >nul 2>&1
    endef

else
    # -------------------- Linux (or other Unix-likes) --------------------
    EXE_EXT :=

    GLFW_INCLUDE := /usr/include
    GLEW_INCLUDE := /usr/include

    LIB_PATHS :=

    LIBS := -lglfw -lGL -lGLEW -lGLU -lyaml-cpp -llua

    define MKDIR_P
        mkdir -p "$(1)"
    endef

endif

# ---------------------------------------------------------------------------
# Directories
# ---------------------------------------------------------------------------
SRC_DIR := src
VENDOR_DIRS := vendor/imgui-docking vendor/stb vendor/ImGuizmo
# BUILD_DIR is determined by $(BUILD_TYPE) above: either `build` or `release`

# ---------------------------------------------------------------------------
# Include Directories
# ---------------------------------------------------------------------------
INCLUDE_DIRS := \
    $(SRC_DIR) \
    $(VENDOR_DIRS) \
    $(GLFW_INCLUDE) \
    $(GLEW_INCLUDE) \
    vendor/stb/include \
    vendor/lua \
    vendor/ImGuizmo \
    vendor/gcml

CXXFLAGS += $(foreach inc,$(INCLUDE_DIRS),-I$(inc))

# ---------------------------------------------------------------------------
# Source Files
# ---------------------------------------------------------------------------
SRC_FILES := $(wildcard $(SRC_DIR)/*.cpp) \
             $(wildcard $(SRC_DIR)/**/*.cpp)

VENDOR_SRC := $(foreach dir, $(VENDOR_DIRS), $(wildcard $(dir)/*.cpp))
STB_SRC := $(wildcard vendor/stb/src/*.cpp) # If stb has .cpp files
ALL_SRC := $(SRC_FILES) $(VENDOR_SRC) $(STB_SRC)

# ---------------------------------------------------------------------------
# Object Files
# ---------------------------------------------------------------------------
OBJ_FILES := $(patsubst %.cpp,$(BUILD_DIR)/%.o,$(ALL_SRC))

# ---------------------------------------------------------------------------
# Target (goes into the same directory as object files)
# ---------------------------------------------------------------------------
TARGET := $(BUILD_DIR)/TesseractEngine$(EXE_EXT)

# ---------------------------------------------------------------------------
# Phony Targets
# ---------------------------------------------------------------------------
.PHONY: all clean debug release

# Default target uses whatever BUILD_TYPE is (default = debug)
all: $(TARGET)

## "debug" target => override BUILD_TYPE
debug:
	@$(MAKE) BUILD_TYPE=debug all

## "release" target => override BUILD_TYPE
release:
	@$(MAKE) BUILD_TYPE=release all

# ---------------------------------------------------------------------------
# Link all object files to create the executable
# ---------------------------------------------------------------------------
$(TARGET): $(OBJ_FILES)
	@echo Linking $@...
	$(CXX) $(CXXFLAGS) -o $@ $^ $(LIB_PATHS) $(LIBS)

# ---------------------------------------------------------------------------
# Pattern rule to compile .cpp files to .o files
# ---------------------------------------------------------------------------
$(BUILD_DIR)/%.o: %.cpp
	@$(call MKDIR_P,$(dir $@))
	@echo Compiling $<...
	$(CXX) $(CXXFLAGS) -c $< -o $@

# ---------------------------------------------------------------------------
# Clean build artifacts
# ---------------------------------------------------------------------------
clean:
	@echo Cleaning up...
	rm -rf build
	rm -rf release