Bring some sanity here. Feel free to specify parameters in any order and in any notation (full name or one-letter).
# Find the Lua library
# --------------------
# On Android/Windows/OSX this just defines the name of the library that
# will be compiled from our bundled sources
# On Linux it will try to load the system library and fallback to compiling
# the bundled one when nothing is found
set(LUA_FOUND false)
set(LUA_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/misc/liblua)
if (ANDROID)
SET(LUA_DEFAULT "liblua5.1.so")
else (ANDROID)
IF(WIN32)
SET(LUA_DEFAULT lua.dll)
ELSE(WIN32)
IF(APPLE)
SET(LUA_DEFAULT lua)
ELSE(APPLE)
#locate the system's lua library
FIND_LIBRARY(LUA_DEFAULT NAMES lua51 lua5.1 lua-5.1 lua PATHS /lib /usr/lib /usr/local/lib /usr/pkg/lib)
IF(${LUA_DEFAULT} MATCHES "LUA_DEFAULT-NOTFOUND")
set(LUA_DEFAULT lua)
ELSE()
set(LUA_FOUND true)
message(STATUS "LibLua 5.1 found at ${LUA_DEFAULT}")
find_path(LUA_INCLUDE_DIR lua.h)
#remove the path (fpc doesn't like it - why?)
GET_FILENAME_COMPONENT(LUA_DEFAULT ${LUA_DEFAULT} NAME)
ENDIF()
ENDIF(APPLE)
ENDIF(WIN32)
ENDIF(ANDROID)
SET(LUA_LIBRARY ${LUA_DEFAULT} CACHE STRING "Lua library to link to; file name without path only!")