%--------------------------
 % @Author: Jingqiao Hu
 % @Date: 2021-09-03 17:52:28
 % @LastEditTime: 2021-09-08 21:01:28

 % return the boolean representing the border-dofs for each micro-ele
 % the inner-dofs = 1 - bdofs
%--------------------------
function [bdofs, ib_dofs, ii_dofs] = expanded_micro_dofs(microx, edofMat_mi)

    bdofs = zeros(microx^2, 8);

    be = zeros(8);
    ib_dofs = zeros(8,8,microx^2);
    ii_dofs = zeros(8,8,microx^2);

    % left
    i = 1;
    for j = 2:microx-1
        bdofs_e = [1,2,7,8];
        idofs_e = setdiff(1:8, bdofs_e);

        ele = (i-1) * microx + j;
        bdofs(ele, bdofs_e) = 1;

        be(:) = 0; be(idofs_e, bdofs_e) = 1;
        ib_dofs(:,:,ele) = be;

        be(:) = 0; be(idofs_e, idofs_e) = 1;
        ii_dofs(:,:,ele) = be;
    end
    % right
    i = microx;
    for j = 2:microx-1
        bdofs_e = 3:6;
        idofs_e = setdiff(1:8, bdofs_e);

        ele = (i-1) * microx + j;
        bdofs(ele, bdofs_e) = 1;

        be(:) = 0; be(idofs_e, bdofs_e) = 1;
        ib_dofs(:,:,ele) = be;

        be(:) = 0; be(idofs_e, idofs_e) = 1;
        ii_dofs(:,:,ele) = be;
    end
    % up
    j = 1;
    for i = 2 : microx-1
        bdofs_e = 5:8;
        idofs_e = setdiff(1:8, bdofs_e);

        ele = (i-1) * microx + j;
        bdofs(ele, bdofs_e) = 1;

        be(:) = 0; be(idofs_e, bdofs_e) = 1;
        ib_dofs(:,:,ele) = be;

        be(:) = 0; be(idofs_e, idofs_e) = 1;
        ii_dofs(:,:,ele) = be;
    end
    % down
    j = microx;
    for i = 2 : microx-1
        bdofs_e = 1:4;
        idofs_e = setdiff(1:8, bdofs_e);

        ele = (i-1) * microx + j;
        bdofs(ele, bdofs_e) = 1;

        be(:) = 0; be(idofs_e, bdofs_e) = 1;
        ib_dofs(:,:,ele) = be;

        be(:) = 0; be(idofs_e, idofs_e) = 1;
        ii_dofs(:,:,ele) = be;
    end
    % left-up corner
    i = 1; j = 1; ele = (i-1) * microx + j;
    bdofs_e = [1,2,5,6,7,8];
    idofs_e = setdiff(1:8, bdofs_e);

    bdofs(ele, bdofs_e) = 1;

    be(:) = 0; be(idofs_e, bdofs_e) = 1;
    ib_dofs(:,:,ele) = be;

    be(:) = 0; be(idofs_e, idofs_e) = 1;
    ii_dofs(:,:,ele) = be;

    % left-down corner
    i = 1; j = microx; ele = (i-1) * microx + j;
    bdofs_e = [1,2,3,4,7,8];
    idofs_e = setdiff(1:8, bdofs_e);

    bdofs(ele, bdofs_e) = 1;
    
    be(:) = 0; be(idofs_e, bdofs_e) = 1;
    ib_dofs(:,:,ele) = be;

    be(:) = 0; be(idofs_e, idofs_e) = 1;
    ii_dofs(:,:,ele) = be;

    % right-up corner
    i = microx; j = 1; ele = (i-1) * microx + j;
    bdofs_e = 3:8;
    idofs_e = setdiff(1:8, bdofs_e);

    bdofs(ele, bdofs_e) = 1;
    
    be(:) = 0; be(idofs_e, bdofs_e) = 1;
    ib_dofs(:,:,ele) = be;

    be(:) = 0; be(idofs_e, idofs_e) = 1;
    ii_dofs(:,:,ele) = be;

    % right-down corner
    i = microx; j = microx; ele = (i-1) * microx + j;
    bdofs_e = 1:6;
    idofs_e = setdiff(1:8, bdofs_e);

    bdofs(ele, bdofs_e) = 1;
    
    be(:) = 0; be(idofs_e, bdofs_e) = 1;
    ib_dofs(:,:,ele) = be;

    be(:) = 0; be(idofs_e, idofs_e) = 1;
    ii_dofs(:,:,ele) = be;

    % inner
    for i = 2:microx-1
        for j = 2:microx-1
            ele = (i-1) * microx + j;
            ii_dofs(:,:,ele) = 1;
        end
    end

    bdofs = bdofs';
end

%     % default value is 9, for the idofs or bdofs not in this micro-ele
%     bdofs = repmat(9, microx^2, 9);
%     idofs = repmat(1:9, microx^2, 1);