cmake_minimum_required(VERSION 3.15)
project(maze VERSION 0.9 LANGUAGES C)

set(CMAKE_C_STANDARD 11)
set(CMAKE_C_STANDARD_REQUIRED ON)

# --- Termux install prefix ---------------------------------------------------
# Termux has no /usr/local; everything lives under $PREFIX
# (/data/data/com.termux/files/usr). CMake's default install prefix would fail
# there, so default to $PREFIX when we detect Termux and the user didn't pass
# -DCMAKE_INSTALL_PREFIX explicitly. Harmless on every other platform.
if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT
   AND DEFINED ENV{PREFIX}
   AND "$ENV{PREFIX}" MATCHES "com\\.termux")
  set(CMAKE_INSTALL_PREFIX "$ENV{PREFIX}" CACHE PATH "Install prefix" FORCE)
endif()

include(GNUInstallDirs)

# --- Wide-character ncurses --------------------------------------------------
# Prefer pkg-config. Termux ships ncursesw.pc (with a compatibility ncurses.pc
# symlink), and pkg-config returns the correct include dir and -lncursesw.
# This avoids FindCurses fragility and Termux's occasionally-broken
# $PREFIX/include/ncurses/ subdirectory symlinks. Falls back to FindCurses on
# systems without pkg-config (or without a .pc file for ncursesw).
find_package(PkgConfig QUIET)
if(PkgConfig_FOUND)
  pkg_check_modules(NCURSESW IMPORTED_TARGET ncursesw)
endif()

# Recursive glob over *.c only (the old "src/*" pulled headers into the target).
# CONFIGURE_DEPENDS re-runs the glob at build time so new files are picked up.
file(GLOB_RECURSE maze_SRC CONFIGURE_DEPENDS src/*.c)
add_executable(maze ${maze_SRC})

target_include_directories(maze PRIVATE src)

# _XOPEN_SOURCE=600 unlocks the wide-character ncurses API (add_wch, get_wch,
# waddnwstr, ...). _DEFAULT_SOURCE re-enables BSD/default declarations that a
# strict _XOPEN_SOURCE would otherwise hide. These previously lived in
# CMAKE_CXX_FLAGS and were silently ignored because this is a C project.
#
# Termux note: if you hit "implicit declaration of function" errors here on
# Android/Bionic, ADD _GNU_SOURCE below rather than removing _XOPEN_SOURCE.
target_compile_definitions(maze PRIVATE
  _DEFAULT_SOURCE
  _XOPEN_SOURCE=600
)

# Extra warnings, but only for Debug builds (configure with
# -DCMAKE_BUILD_TYPE=Debug). The $<CONFIG:Debug> generator expression emits each
# flag only when the active configuration is Debug, so this works under both
# single-config generators (Make/Ninja, where the build type is fixed at
# configure time) and multi-config generators (Visual Studio/Xcode/Ninja
# Multi-Config, where it is chosen at build time). GCC/Clang flag syntax, which
# is fine for Linux and Termux.
target_compile_options(maze PRIVATE
  $<$<CONFIG:Debug>:-Wall>
  $<$<CONFIG:Debug>:-Wextra>
)

if(TARGET PkgConfig::NCURSESW)
  target_link_libraries(maze PRIVATE PkgConfig::NCURSESW)
else()
  set(CURSES_NEED_WIDE TRUE)
  set(CURSES_NEED_NCURSES TRUE)
  find_package(Curses REQUIRED)
  target_include_directories(maze PRIVATE ${CURSES_INCLUDE_DIRS})
  target_link_libraries(maze PRIVATE ${CURSES_LIBRARIES})
endif()

# --- Install -----------------------------------------------------------------
install(TARGETS maze RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})

# Man page installs only if it is present.
if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/doc/maze.1")
  install(FILES doc/maze.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1)
endif()