# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# ZSTD_HOME environmental variable is used to check for Zstd headers and static library

# ZSTD_INCLUDE_DIR: directory containing headers
# ZSTD_LIBS: directory containing zstd libraries
# ZSTD_STATIC_LIB: path to libzstd.a
# ZSTD_FOUND: whether zstd has been found

if( NOT "${ZSTD_HOME}" STREQUAL "")
  file (TO_CMAKE_PATH "${ZSTD_HOME}" _zstd_path)
endif()

message (STATUS "ZSTD_HOME: ${ZSTD_HOME}")

if (NOT ZSTD_STATIC_LIB_NAME)
  set (ZSTD_STATIC_LIB_NAME ${CMAKE_STATIC_LIBRARY_PREFIX}zstd)
endif()

find_path (ZSTD_INCLUDE_DIR zstd.h HINTS
        ${_zstd_path}
        NO_DEFAULT_PATH
        PATH_SUFFIXES "include")

find_library (ZSTD_LIBRARIES NAMES ${ZSTD_STATIC_LIB_NAME} HINTS
        ${_zstd_path}
        PATH_SUFFIXES "lib")

if (ZSTD_INCLUDE_DIR AND ZSTD_LIBRARIES)
  set (ZSTD_FOUND TRUE)
  get_filename_component (ZSTD_LIBS ${ZSTD_LIBRARIES} PATH)
  set (ZSTD_HEADER_NAME zstd.h)
  set (ZSTD_HEADER ${ZSTD_INCLUDE_DIR}/${ZSTD_HEADER_NAME})
  set (ZSTD_STATIC_LIB ${ZSTD_LIBS}/${ZSTD_STATIC_LIB_NAME}${CMAKE_STATIC_LIBRARY_SUFFIX})
else ()
  set (ZSTD_FOUND FALSE)
endif ()

if (ZSTD_FOUND)
  message (STATUS "Found the zstd header: ${ZSTD_HEADER}")
  message (STATUS "Found the zstd library: ${ZSTD_STATIC_LIB}")
else()
  if (_ZSTD_path)
    set (ZSTD_ERR_MSG "Could not find zstd. Looked in ${_zstd_path}.")
  else ()
    set (ZSTD_ERR_MSG "Could not find zstd in system search paths.")
  endif()

  if (ZSTD_FIND_REQUIRED)
    message (FATAL_ERROR "${ZSTD_ERR_MSG}")
  else ()
    message (STATUS "${ZSTD_ERR_MSG}")
  endif ()
endif()

mark_as_advanced (
        ZSTD_INCLUDE_DIR
        ZSTD_STATIC_LIB
        ZSTD_LIBS
        ZSTD_LIBRARIES
)