# - Try to find FFMPEG
# Once done this will define
#  
#  FFMPEG_FOUND    - system has FFMPEG
#  FFMPEG_INCLUDE_DIR  - the include directories
#  FFMPEG_LIBRARY_DIR  - the directory containing the libraries
#  FFMPEG_LIBRARIES  - link these to use FFMPEG
#  FFMPEG_SWSCALE_FOUND  - FFMPEG also has SWSCALE
#   

IF( USE_FFMPEG )

  SET( FFMPEG_HEADERS avformat.h avcodec.h avutil.h avdevice.h )
  SET( FFMPEG_PATH_SUFFIXES libavformat libavcodec libavutil libavdevice libffmpeg )
  SET( FFMPEG_SWS_HEADERS swscale.h )
  SET( FFMPEG_SWS_PATH_SUFFIXES libswscale )


  SET( FFMPEG_LIBRARIES avformat avcodec avutil avdevice )
  SET( FFMPEG_SWS_LIBRARIES swscale )
  INCLUDE(FindPkgConfig)
  if ( PKG_CONFIG_FOUND )
    pkg_check_modules( AVFORMAT libavformat )
    pkg_check_modules( AVCODEC libavcodec )
    pkg_check_modules( AVUTIL libavutil )
    pkg_check_modules( AVDEVICE libavdevice )
    pkg_check_modules( SWSCALE libswscale )
  endif ( PKG_CONFIG_FOUND )

  SET( FFMPEG_LIBRARY_DIR   ${AVFORMAT_LIBRARY_DIRS}
          ${AVCODEC_LIBRARY_DIRS}
          ${AVUTIL_LIBRARY_DIRS}
          ${AVDEVICE_LIBRARY_DIRS} )
  SET( FFMPEG_INCLUDE_PATHS ${AVFORMAT_INCLUDE_DIRS}
          ${AVCODEC_INCLUDE_DIRS}
          ${AVUTIL_INCLUDE_DIRS}
          ${AVDEVICE_INCLUDE_DIRS} )


  # add in swscale if found
  IF ( SWSCALE_FOUND )
    SET( FFMPEG_LIBRARY_DIR   ${FFMPEG_LIBRARY_DIR}
                ${SWSCALE_LIBRARY_DIRS} )
    SET( FFMPEG_INCLUDE_PATHS ${FFMPEG_INCLUDE_PATHS}
                ${SWSCALE_INCLUDE_DIRS} )
    SET( FFMPEG_HEADERS       ${FFMPEG_HEADERS}
                ${FFMPEG_SWS_HEADERS} )
    SET( FFMPEG_PATH_SUFFIXES ${FFMPEG_PATH_SUFFIXES}
                ${FFMPEG_SWS_PATH_SUFFIXES} )
    SET( FFMPEG_LIBRARIES     ${FFMPEG_LIBRARIES}
                ${FFMPEG_SWS_LIBRARIES} )
  ENDIF ( SWSCALE_FOUND )

  # find includes
  SET( INC_SUCCESS 0 )
  SET( TMP_ TMP-NOTFOUND )
  SET( FFMPEG_INCLUDE_DIR ${FFMPEG_INCLUDE_PATHS} )
  FOREACH( INC_ ${FFMPEG_HEADERS} )
    message( "checking: " ${INC_} )

    FIND_PATH( TMP_ ${INC_}
          PATHS ${FFMPEG_INCLUDE_PATHS}
          PATH_SUFFIXES ${FFMPEG_PATH_SUFFIXES} )
    IF ( TMP_ )
        message( "found: " ${TMP_} )
        MATH( EXPR INC_SUCCESS ${INC_SUCCESS}+1 )
        SET( FFMPEG_INCLUDE_DIR ${FFMPEG_INCLUDE_DIR} ${TMP_} )
    ENDIF ( TMP_ )
    SET( TMP_ TMP-NOTFOUND )
  ENDFOREACH( INC_ )

  # clear out duplicates
  if(NOT "${FFMPEG_INCLUDE_DIR}" MATCHES "")
    LIST( REMOVE_DUPLICATES FFMPEG_INCLUDE_DIR )
  endif(NOT "${FFMPEG_INCLUDE_DIR}" MATCHES "")
  if(NOT "${FFMPEG_LIBRARY_DIR}" MATCHES "")
    LIST( REMOVE_DUPLICATES FFMPEG_LIBRARY_DIR )
  endif(NOT "${FFMPEG_LIBRARY_DIR}" MATCHES "")

  # find the full paths of the libraries
  SET( TMP_ TMP-NOTFOUND )
  IF ( NOT WIN32 )
    FOREACH( LIB_ ${FFMPEG_LIBRARIES} )
        FIND_LIBRARY( TMP_ NAMES ${LIB_} PATHS ${FFMPEG_LIBRARY_DIR} )
        IF ( TMP_ )
          SET( FFMPEG_LIBRARIES_FULL ${FFMPEG_LIBRARIES_FULL} ${TMP_} )
        ENDIF ( TMP_ )
        SET( TMP_ TMP-NOTFOUND )
    ENDFOREACH( LIB_ )
    SET ( FFMPEG_LIBRARIES ${FFMPEG_LIBRARIES_FULL} )
  ENDIF( NOT WIN32 )
  
  UNSET( TMP_ )

  LIST( LENGTH FFMPEG_HEADERS LIST_SIZE_ )

  SET( FFMPEG_FOUND FALSE )
  SET( FFMPEG_SWSCALE_FOUND FALSE )
  IF ( ${INC_SUCCESS} EQUAL ${LIST_SIZE_} )
    SET( FFMPEG_FOUND TRUE )
    SET( FFMPEG_SWSCALE_FOUND ${SWSCALE_FOUND} )
  ENDIF ( ${INC_SUCCESS} EQUAL ${LIST_SIZE_} ) 



  IF( NOT WIN32 )
      IF( NOT FFMPEG_FOUND )
          SET( USE_FFMPEG FALSE )
      ELSE()
          INCLUDE_DIRECTORIES( ${LIB_DIR}/ffmpeg )
          #SET( CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS} -D__STDC_CONSTANT_MACROS )
          INCLUDE_DIRECTORIES(${FFMPEG_INCLUDE_DIR} ${FFMPEG_INCLUDE_DIRS})
          ADD_LIBRARY( FFmpeg ${LIB_DIR}/ffmpeg/LibAvContextHandle.cpp )
          TARGET_LINK_LIBRARIES( FFmpeg ${FFMPEG_LIBRARIES} )
          SET( LINKER_LIBS ${LINKER_LIBS} FFmpeg )
      ENDIF()
  ELSE()
      SET( USE_FFMPEG FALSE )
  ENDIF()
ENDIF()