# Written in 2016 by Henrik Steffen Gaßmann <henrik@gassmann.onl>
#
# To the extent possible under law, the author(s) have dedicated all copyright
# and related and neighboring rights to this software to the public domain
# worldwide. This software is distributed without any warranty.
#
# You should have received a copy of the CC0 Public Domain Dedication along with
# this software. If not, see
#
# http://creativecommons.org/publicdomain/zero/1.0/
#
# ##############################################################################
# Tries to find the local libsodium installation.
#
# On Windows the sodium_DIR environment variable is used as a default hint which
# can be overridden by setting the corresponding cmake variable.
#
# Once done the following variables will be defined:
#
# sodium_FOUND sodium_INCLUDE_DIR sodium_LIBRARY_DEBUG sodium_LIBRARY_RELEASE
# sodium_VERSION_STRING
#
# Furthermore an imported "sodium" target is created.
#

if(CMAKE_C_COMPILER_ID STREQUAL "GNU" OR CMAKE_C_COMPILER_ID STREQUAL "Clang")
    set(_GCC_COMPATIBLE 1)
endif()

# static library option
if(NOT DEFINED sodium_USE_STATIC_LIBS)
    option(sodium_USE_STATIC_LIBS "enable to statically link against sodium" OFF)
endif()
if(NOT (sodium_USE_STATIC_LIBS EQUAL sodium_USE_STATIC_LIBS_LAST))
    unset(sodium_LIBRARY CACHE)
    unset(sodium_LIBRARY_DEBUG CACHE)
    unset(sodium_LIBRARY_RELEASE CACHE)
    unset(sodium_DLL_DEBUG CACHE)
    unset(sodium_DLL_RELEASE CACHE)
    set(sodium_USE_STATIC_LIBS_LAST
            ${sodium_USE_STATIC_LIBS}
            CACHE INTERNAL "internal change tracking variable")
endif()

# ##############################################################################
# UNIX
if(UNIX)
    # import pkg-config
    find_package(PkgConfig QUIET)
    if(PKG_CONFIG_FOUND)
        pkg_check_modules(sodium_PKG QUIET libsodium)
    endif()

    if(sodium_USE_STATIC_LIBS)
        if(sodium_PKG_STATIC_LIBRARIES)
            foreach(_libname ${sodium_PKG_STATIC_LIBRARIES})
                if(NOT _libname MATCHES "^lib.*\\.a$") # ignore strings already ending
                    # with .a
                    list(INSERT sodium_PKG_STATIC_LIBRARIES 0 "lib${_libname}.a")
                endif()
            endforeach()
            list(REMOVE_DUPLICATES sodium_PKG_STATIC_LIBRARIES)
        else()
            # if pkgconfig for libsodium doesn't provide static lib info, then
            # override PKG_STATIC here..
            set(sodium_PKG_STATIC_LIBRARIES libsodium.a)
        endif()

        set(XPREFIX sodium_PKG_STATIC)
    else()
        if(sodium_PKG_LIBRARIES STREQUAL "")
            set(sodium_PKG_LIBRARIES sodium)
        endif()

        set(XPREFIX sodium_PKG)
    endif()

    find_path(sodium_INCLUDE_DIR sodium.h HINTS ${${XPREFIX}_INCLUDE_DIRS})
    find_library(sodium_LIBRARY_DEBUG
            NAMES ${${XPREFIX}_LIBRARIES}
            HINTS ${${XPREFIX}_LIBRARY_DIRS})
    find_library(sodium_LIBRARY_RELEASE
            NAMES ${${XPREFIX}_LIBRARIES}
            HINTS ${${XPREFIX}_LIBRARY_DIRS})

    # ############################################################################
    # Windows
elseif(WIN32)
    set(sodium_DIR "$ENV{sodium_DIR}" CACHE FILEPATH "sodium install directory")
    mark_as_advanced(sodium_DIR)

    find_path(sodium_INCLUDE_DIR sodium.h
            HINTS ${sodium_DIR}
            PATH_SUFFIXES include)

    if(MSVC)
        # detect target architecture
        file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/arch.c" [=[
            #if defined _M_IX86
            #error ARCH_VALUE x86_32
            #elif defined _M_X64
            #error ARCH_VALUE x86_64
            #endif
            #error ARCH_VALUE unknown
        ]=])
        try_compile(_UNUSED_VAR "${CMAKE_CURRENT_BINARY_DIR}"
                "${CMAKE_CURRENT_BINARY_DIR}/arch.c"
                OUTPUT_VARIABLE _COMPILATION_LOG)
        string(REGEX
                REPLACE ".*ARCH_VALUE ([a-zA-Z0-9_]+).*"
                "\\1"
                _TARGET_ARCH
                "${_COMPILATION_LOG}")

        # construct library path
        if(_TARGET_ARCH STREQUAL "x86_32")
            string(APPEND _PLATFORM_PATH "Win32")
        elseif(_TARGET_ARCH STREQUAL "x86_64")
            string(APPEND _PLATFORM_PATH "x64")
        else()
            message(
                    FATAL_ERROR
                    "the ${_TARGET_ARCH} architecture is not supported by Findsodium.cmake."
            )
        endif()
        string(APPEND _PLATFORM_PATH "/$$CONFIG$$")

        if(MSVC_VERSION LESS 1900)
            math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 60")
        else()
            math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 50")
        endif()
        string(APPEND _PLATFORM_PATH "/v${_VS_VERSION}")

        if(sodium_USE_STATIC_LIBS)
            string(APPEND _PLATFORM_PATH "/static")
        else()
            string(APPEND _PLATFORM_PATH "/dynamic")
        endif()

        string(REPLACE "$$CONFIG$$"
                "Debug"
                _DEBUG_PATH_SUFFIX
                "${_PLATFORM_PATH}")
        string(REPLACE "$$CONFIG$$"
                "Release"
                _RELEASE_PATH_SUFFIX
                "${_PLATFORM_PATH}")

        find_library(sodium_LIBRARY_DEBUG libsodium.lib
                HINTS ${sodium_DIR}
                PATH_SUFFIXES ${_DEBUG_PATH_SUFFIX})
        find_library(sodium_LIBRARY_RELEASE libsodium.lib
                HINTS ${sodium_DIR}
                PATH_SUFFIXES ${_RELEASE_PATH_SUFFIX})
        if(NOT sodium_USE_STATIC_LIBS)
            set(CMAKE_FIND_LIBRARY_SUFFIXES_BCK ${CMAKE_FIND_LIBRARY_SUFFIXES})
            set(CMAKE_FIND_LIBRARY_SUFFIXES ".dll")
            find_library(sodium_DLL_DEBUG libsodium
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES ${_DEBUG_PATH_SUFFIX})
            find_library(sodium_DLL_RELEASE libsodium
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES ${_RELEASE_PATH_SUFFIX})
            set(CMAKE_FIND_LIBRARY_SUFFIXES ${CMAKE_FIND_LIBRARY_SUFFIXES_BCK})
        endif()

    elseif(_GCC_COMPATIBLE)
        if(sodium_USE_STATIC_LIBS)
            find_library(sodium_LIBRARY_DEBUG libsodium.a
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES lib)
            find_library(sodium_LIBRARY_RELEASE libsodium.a
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES lib)
        else()
            find_library(sodium_LIBRARY_DEBUG libsodium.dll.a
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES lib)
            find_library(sodium_LIBRARY_RELEASE libsodium.dll.a
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES lib)

            file(GLOB _DLL
                    LIST_DIRECTORIES false
                    RELATIVE "${sodium_DIR}/bin"
                    "${sodium_DIR}/bin/libsodium*.dll")
            find_library(sodium_DLL_DEBUG ${_DLL} libsodium
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES bin)
            find_library(sodium_DLL_RELEASE ${_DLL} libsodium
                    HINTS ${sodium_DIR}
                    PATH_SUFFIXES bin)
        endif()
    else()
        message(FATAL_ERROR "this platform is not supported by FindSodium.cmake")
    endif()

    # ############################################################################
    # unsupported
else()
    message(FATAL_ERROR "this platform is not supported by FindSodium.cmake")
endif()

# ##############################################################################
# common stuff

# extract sodium version
if(sodium_INCLUDE_DIR)
    set(_VERSION_HEADER "${sodium_INCLUDE_DIR}/sodium/version.h")
    if(EXISTS "${_VERSION_HEADER}")
        file(READ "${_VERSION_HEADER}" _VERSION_HEADER_CONTENT)
        string(REGEX
                REPLACE ".*define[ \t]+SODIUM_VERSION_STRING[^\"]+\"([^\"]+)\".*"
                "\\1"
                sodium_VERSION_STRING
                "${_VERSION_HEADER_CONTENT}")
        set(sodium_VERSION_STRING "${sodium_VERSION_STRING}")
    endif()
endif()

# communicate results
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(sodium
        REQUIRED_VARS
        sodium_LIBRARY_RELEASE
        sodium_LIBRARY_DEBUG
        sodium_INCLUDE_DIR
        VERSION_VAR
        sodium_VERSION_STRING)

# mark file paths as advanced
mark_as_advanced(sodium_INCLUDE_DIR)
mark_as_advanced(sodium_LIBRARY_DEBUG)
mark_as_advanced(sodium_LIBRARY_RELEASE)
if(WIN32)
    mark_as_advanced(sodium_DLL_DEBUG)
    mark_as_advanced(sodium_DLL_RELEASE)
endif()

# create imported target
if(sodium_USE_STATIC_LIBS)
    set(_LIB_TYPE STATIC)
else()
    set(_LIB_TYPE SHARED)
endif()
add_library(sodium ${_LIB_TYPE} IMPORTED)

set_target_properties(sodium
        PROPERTIES INTERFACE_INCLUDE_DIRECTORIES
        "${sodium_INCLUDE_DIR}"
        IMPORTED_LINK_INTERFACE_LANGUAGES
        "C")

if(sodium_USE_STATIC_LIBS)
    set_target_properties(sodium
            PROPERTIES INTERFACE_COMPILE_DEFINITIONS
            "SODIUM_STATIC"
            IMPORTED_LOCATION
            "${sodium_LIBRARY_RELEASE}"
            IMPORTED_LOCATION_DEBUG
            "${sodium_LIBRARY_DEBUG}")
else()
    if(UNIX)
        set_target_properties(sodium
                PROPERTIES IMPORTED_LOCATION
                "${sodium_LIBRARY_RELEASE}"
                IMPORTED_LOCATION_DEBUG
                "${sodium_LIBRARY_DEBUG}")
    elseif(WIN32)
        set_target_properties(sodium
                PROPERTIES IMPORTED_IMPLIB
                "${sodium_LIBRARY_RELEASE}"
                IMPORTED_IMPLIB_DEBUG
                "${sodium_LIBRARY_DEBUG}")
        if(NOT (sodium_DLL_DEBUG MATCHES ".*-NOTFOUND"))
            set_target_properties(sodium
                    PROPERTIES IMPORTED_LOCATION_DEBUG
                    "${sodium_DLL_DEBUG}")
        endif()
        if(NOT (sodium_DLL_RELEASE MATCHES ".*-NOTFOUND"))
            set_target_properties(sodium
                    PROPERTIES IMPORTED_LOCATION_RELWITHDEBINFO
                    "${sodium_DLL_RELEASE}"
                    IMPORTED_LOCATION_MINSIZEREL
                    "${sodium_DLL_RELEASE}"
                    IMPORTED_LOCATION_RELEASE
                    "${sodium_DLL_RELEASE}")
        endif()
    endif()
endif()