##### http://autoconf-archive.cryp.to/ax_lib_sqlite3.html
#
# SYNOPSIS
#
#   AX_LIB_SQLITE3([MINIMUM-VERSION],[DEFAULT])
#
# DESCRIPTION
#
#   Test for the SQLite 3 library of a particular version (or newer)
#
#   This macro takes only one optional argument, required version of
#   SQLite 3 library. If required version is not passed, 3.0.0 is used
#   in the test of existance of SQLite 3.
#
#   If no intallation prefix to the installed SQLite library is given
#   the macro searches under /usr, /usr/local, and /opt.
#
#   This macro calls:
#
#     AC_SUBST(SQLITE3_CPPFLAGS)
#     AC_SUBST(SQLITE3_LDFLAGS)
#     AC_SUBST(SQLITE3_VERSION)
#
#   And sets:
#
#     HAVE_SQLITE3
#
# LAST MODIFICATION
#
#   2006-07-15
#
# COPYLEFT
#
#   Copyright (c) 2006 Mateusz Loskot <mateusz@loskot.net>
#
#   Copying and distribution of this file, with or without
#   modification, are permitted in any medium without royalty provided
#   the copyright notice and this notice are preserved.

AC_DEFUN([AX_LIB_SQLITE3],
[
    AC_ARG_WITH([sqlite3],
        AC_HELP_STRING(
            [--with-sqlite3@<:@=ARG@:>@],
            [use SQLite 3 library @<:@default=no@:>@, optionally specify the prefix for sqlite3 library]
        ),
        [
        if test "$withval" = "no"; then
            WANT_SQLITE3="no"
        elif test "$withval" = "yes"; then
            WANT_SQLITE3="yes"
            ac_sqlite3_path=""
        else
            WANT_SQLITE3="yes"
            ac_sqlite3_path="$withval"
        fi
        ],
        [WANT_SQLITE3="no"]
    )

    SQLITE3_CFLAGS=""
    SQLITE3_LDFLAGS=""
    SQLITE3_VERSION=""

    if test "x$WANT_SQLITE3" = "xyes"; then

        ac_sqlite3_header="sqlite3.h"

        sqlite3_version_req=ifelse([$1], [], [3.0.0], [$1])
        sqlite3_version_req_shorten=`expr $sqlite3_version_req : '\([[0-9]]*\.[[0-9]]*\)'`
        sqlite3_version_req_major=`expr $sqlite3_version_req : '\([[0-9]]*\)'`
        sqlite3_version_req_minor=`expr $sqlite3_version_req : '[[0-9]]*\.\([[0-9]]*\)'`
        sqlite3_version_req_micro=`expr $sqlite3_version_req : '[[0-9]]*\.[[0-9]]*\.\([[0-9]]*\)'`
        if test "x$sqlite3_version_req_micro" = "x" ; then
            sqlite3_version_req_micro="0"
        fi

        sqlite3_version_req_number=`expr $sqlite3_version_req_major \* 1000000 \
                                   \+ $sqlite3_version_req_minor \* 1000 \
                                   \+ $sqlite3_version_req_micro`

        AC_MSG_CHECKING([for SQLite3 library >= $sqlite3_version_req])

        if test "$ac_sqlite3_path" != ""; then
            ac_sqlite3_ldflags="-L$ac_sqlite3_path/lib"
            ac_sqlite3_cppflags="-I$ac_sqlite3_path/include"
        else
            for ac_sqlite3_path_tmp in /usr /usr/local /opt ; do
                if test -f "$ac_sqlite3_path_tmp/include/$ac_sqlite3_header" \
                    && test -r "$ac_sqlite3_path_tmp/include/$ac_sqlite3_header"; then
                    ac_sqlite3_path=$ac_sqlite3_path_tmp
                    ac_sqlite3_ldflags="-I$ac_sqlite3_path_tmp/include"
                    ac_sqlite3_cppflags="-L$ac_sqlite3_path_tmp/lib"
                    break;
                fi
            done
        fi

        ac_sqlite3_ldflags="$ac_sqlite3_ldflags -lsqlite3"

        saved_CPPFLAGS="$CPPFLAGS"
        CPPFLAGS="$CPPFLAGS $ac_sqlite3_cppflags"

dnl        AC_LANG_PUSH([C++])
        AC_COMPILE_IFELSE(
            [
            AC_LANG_PROGRAM([[@%:@include <sqlite3.h>]],
                [[
#if (SQLITE_VERSION_NUMBER >= $sqlite3_version_req_number)
// Everything is okay
#else
#  error SQLite version is too old
#endif
                ]]
            )
            ],
            [
            found_sqlite3="yes"
            AC_MSG_RESULT([yes])
            ],
            [
            found_sqlite3="no"
            AC_MSG_RESULT([no])
            ]
        )
dnl      AC_LANG_POP([C++])

        CPPFLAGS="$saved_CPPFLAGS"

        if test "$found_sqlite3" = "yes"; then

            SQLITE3_CPPFLAGS="$ac_sqlite3_cppflags"
            SQLITE3_LDFLAGS="$ac_sqlite3_ldflags"

            ac_sqlite3_header_path="$ac_sqlite3_path/include/$ac_sqlite3_header"

            dnl Retrieve SQLite release version
            if test "x$ac_sqlite3_header_path" != "x"; then
                ac_sqlite3_version=`cat $ac_sqlite3_header_path \
                    | grep '#define.*SQLITE_VERSION.*\"' | sed -e 's/.* "//' \
                        | sed -e 's/"//'`
                if test $ac_sqlite3_version != ""; then
                    SQLITE3_VERSION=$ac_sqlite3_version
                else
                    AC_MSG_WARN([Can not find SQLITE_VERSION macro in sqlite3.h header to retrieve SQLite version!])
                fi
            fi

            AC_SUBST(SQLITE3_CPPFLAGS)
            AC_SUBST(SQLITE3_LDFLAGS)
            AC_SUBST(SQLITE3_VERSION)
            AC_DEFINE(HAVE_SQLITE3, [1], [Define to 1 if SQLite libraries are available])
        fi
    fi
])