## Parses the VERSION_STRING variable and places
## the first, second and third number values in
## the major, minor and patch variables.
function( parse_version VERSION_STRING )

    string ( FIND ${VERSION_STRING} "-" STRING_INDEX )

    if ( ${STRING_INDEX} GREATER -1 )
        math ( EXPR STRING_INDEX "${STRING_INDEX} + 1" )
        string ( SUBSTRING ${VERSION_STRING} ${STRING_INDEX} -1 VERSION_BUILD )
    endif ()

    string ( REGEX MATCHALL "[0123456789]+" VERSIONS ${VERSION_STRING} )
    list ( LENGTH VERSIONS VERSION_COUNT )

    if ( ${VERSION_COUNT} GREATER 0)
        list ( GET VERSIONS 0 MAJOR )
        set ( VERSION_MAJOR ${MAJOR} PARENT_SCOPE )
        set ( TEMP_VERSION_STRING "${MAJOR}" )
    endif ()

    if ( ${VERSION_COUNT} GREATER 1 )
        list ( GET VERSIONS 1 MINOR )
        set ( VERSION_MINOR ${MINOR} PARENT_SCOPE )
        set ( TEMP_VERSION_STRING "${TEMP_VERSION_STRING}.${MINOR}" )
    endif ()

    if ( ${VERSION_COUNT} GREATER 2 )
        list ( GET VERSIONS 2 PATCH )
        set ( VERSION_PATCH ${PATCH} PARENT_SCOPE )
        set ( TEMP_VERSION_STRING "${TEMP_VERSION_STRING}.${PATCH}" )
    endif ()

    if ( DEFINED VERSION_BUILD )
        set ( VERSION_BUILD "${VERSION_BUILD}" PARENT_SCOPE )
    endif ()

    set ( VERSION_STRING "${TEMP_VERSION_STRING}" PARENT_SCOPE )

endfunction ()

## Gets the current version of the repository
## using versioning tags and git describe.
## Passes back a packaging version string
## and a library version string.
function ( get_version DEFAULT_VERSION_STRING )

    parse_version ( ${DEFAULT_VERSION_STRING} )

    find_program ( GIT NAMES git )

    if ( GIT )

        execute_process ( COMMAND "git describe --dirty --long --match [0-9]* 2>/dev/null"
                          WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
                          OUTPUT_VARIABLE GIT_TAG_STRING
                          OUTPUT_STRIP_TRAILING_WHITESPACE
                          RESULT_VARIABLE RESULT )

        if ( ${RESULT} EQUAL 0 )

            parse_version ( ${GIT_TAG_STRING} )

        endif ()

    endif ()

    set( VERSION_STRING "${VERSION_STRING}" PARENT_SCOPE )
    set( VERSION_MAJOR  "${VERSION_MAJOR}" PARENT_SCOPE )
    set( VERSION_MINOR  "${VERSION_MINOR}" PARENT_SCOPE )
    set( VERSION_PATCH  "${VERSION_PATCH}" PARENT_SCOPE )
    set( VERSION_BUILD  "${VERSION_BUILD}" PARENT_SCOPE )

endfunction()

function(get_git_rev GIT_REVISION_OUT)
    find_package(Git)

    if(Git_FOUND)
        execute_process(
            COMMAND ${GIT_EXECUTABLE} describe --tags
            OUTPUT_VARIABLE GIT_DESCRIBE
            OUTPUT_STRIP_TRAILING_WHITESPACE
            RESULT_VARIABLE _GIT_DESCRIBE_RESULT
            ERROR_QUIET)
        if(NOT _GIT_DESCRIBE_RESULT EQUAL 0)
            execute_process(
                COMMAND ${GIT_EXECUTABLE} describe
                OUTPUT_VARIABLE GIT_DESCRIBE
                OUTPUT_STRIP_TRAILING_WHITESPACE
                RESULT_VARIABLE _GIT_DESCRIBE_RESULT
                ERROR_QUIET)
        endif()

        execute_process(
            COMMAND ${GIT_EXECUTABLE} rev-parse HEAD
            WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
            OUTPUT_VARIABLE GIT_REVISION
            OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET)
        set(${GIT_REVISION_OUT} "${GIT_REVISION}" PARENT_SCOPE)
    else()
        set(${GIT_REVISION_OUT} "" PARENT_SCOPE)
    endif()
endfunction()

## Configure Copyright File for Debian Package
function( configure_pkg PACKAGE_NAME_T COMPONENT_NAME_T PACKAGE_VERSION_T MAINTAINER_NM_T MAINTAINER_EMAIL_T)
    # Check If Debian Platform
    find_file (DEBIAN debian_version debconf.conf PATHS /etc)
    if(DEBIAN)
        set( BUILD_DEBIAN_PKGING_FLAG ON CACHE BOOL "Internal Status Flag to indicate Debian Packaging Build" FORCE )
        set_debian_pkg_cmake_flags( ${PACKAGE_NAME_T} ${PACKAGE_VERSION_T}
                                    ${MAINTAINER_NM_T} ${MAINTAINER_EMAIL_T} )

        # Create debian directory in build tree
        file(MAKE_DIRECTORY "${CMAKE_BINARY_DIR}/DEBIAN")

        # Configure the copyright file
        configure_file(
            "${CMAKE_SOURCE_DIR}/DEBIAN/copyright.in"
            "${CMAKE_BINARY_DIR}/DEBIAN/copyright"
            @ONLY
        )

        # Install copyright file
        install ( FILES "${CMAKE_BINARY_DIR}/DEBIAN/copyright"
                DESTINATION "${CMAKE_INSTALL_DOCDIR}"
                COMPONENT ${COMPONENT_NAME_T} )

        # Configure the changelog file
        configure_file(
            "${CMAKE_SOURCE_DIR}/DEBIAN/changelog.in"
            "${CMAKE_BINARY_DIR}/DEBIAN/changelog.Debian"
            @ONLY
        )

        # Install Change Log
        find_program ( DEB_GZIP_EXEC gzip )
        if(EXISTS "${CMAKE_BINARY_DIR}/DEBIAN/changelog.Debian" )
            execute_process(
            COMMAND ${DEB_GZIP_EXEC} -f -n -9 "${CMAKE_BINARY_DIR}/DEBIAN/changelog.Debian"
            WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/DEBIAN"
            RESULT_VARIABLE result
            OUTPUT_VARIABLE output
            ERROR_VARIABLE error
            )
            if(NOT ${result} EQUAL 0)
                message(FATAL_ERROR "Failed to compress: ${error}")
            endif()
            install ( FILES "${CMAKE_BINARY_DIR}/DEBIAN/${DEB_CHANGELOG_INSTALL_FILENM}"
                    DESTINATION ${CMAKE_INSTALL_DOCDIR}
                    COMPONENT ${COMPONENT_NAME_T})
        endif()
      
    else()
        # License file
        install ( FILES ${LICENSE_FILE}
            DESTINATION ${CMAKE_INSTALL_DOCDIR} RENAME LICENSE.txt
            COMPONENT ${COMPONENT_NAME_T})
    endif()
endfunction()

# Set variables for changelog and copyright
# For Debian specific Packages
function( set_debian_pkg_cmake_flags DEB_PACKAGE_NAME_T DEB_PACKAGE_VERSION_T DEB_MAINTAINER_NM_T DEB_MAINTAINER_EMAIL_T )
    # Setting configure flags
    set( DEB_PACKAGE_NAME             "${DEB_PACKAGE_NAME_T}" CACHE STRING "Debian Package Name" )
    set( DEB_PACKAGE_VERSION          "${DEB_PACKAGE_VERSION_T}" CACHE STRING "Debian Package Version String" )
    set( DEB_MAINTAINER_NAME          "${DEB_MAINTAINER_NM_T}" CACHE STRING "Debian Package Maintainer Name" )
    set( DEB_MAINTAINER_EMAIL         "${DEB_MAINTAINER_EMAIL_T}" CACHE STRING "Debian Package Maintainer Email" )
    set( DEB_COPYRIGHT_YEAR           "2025" CACHE STRING "Debian Package Copyright Year" )
    set( DEB_LICENSE                  "MIT" CACHE STRING "Debian Package License Type" )
    set( DEB_CHANGELOG_INSTALL_FILENM "changelog.Debian.gz" CACHE STRING "Debian Package ChangeLog File Name" )

    # Get TimeStamp
    find_program( DEB_DATE_TIMESTAMP_EXEC date )
    set ( DEB_TIMESTAMP_FORMAT_OPTION "-R" )
    execute_process (
        COMMAND ${DEB_DATE_TIMESTAMP_EXEC} ${DEB_TIMESTAMP_FORMAT_OPTION}
        OUTPUT_VARIABLE TIMESTAMP_T
    )
    set( DEB_TIMESTAMP                "${TIMESTAMP_T}" CACHE STRING "Current Time Stamp for Copyright/Changelog" )

    message(STATUS "DEB_PACKAGE_NAME             : ${DEB_PACKAGE_NAME}" )
    message(STATUS "DEB_PACKAGE_VERSION          : ${DEB_PACKAGE_VERSION}" )
    message(STATUS "DEB_MAINTAINER_NAME          : ${DEB_MAINTAINER_NAME}" )
    message(STATUS "DEB_MAINTAINER_EMAIL         : ${DEB_MAINTAINER_EMAIL}" )
    message(STATUS "DEB_COPYRIGHT_YEAR           : ${DEB_COPYRIGHT_YEAR}" )
    message(STATUS "DEB_LICENSE                  : ${DEB_LICENSE}" )
    message(STATUS "DEB_TIMESTAMP                : ${DEB_TIMESTAMP}" )
    message(STATUS "DEB_CHANGELOG_INSTALL_FILENM : ${DEB_CHANGELOG_INSTALL_FILENM}" )
endfunction()