#include <petsc/finclude/petscsys.h>
#include <petsc/finclude/petscbag.h>
#include <petsc/finclude/petscviewer.h>

module ex5f90module
  use petscsys
  use petscbag
!     Data structure used to contain information about the problem
!     You can add physical values etc here

  type tuple
    PetscReal:: x1, x2
  end type tuple

  type bag_data_type
    PetscScalar :: x
    PetscReal :: y
    PetscInt  :: nxc
    PetscReal :: rarray(3)
    PetscBool  :: t
    PetscBool  :: tarray(3)
    PetscEnum :: enum
    character*(80) :: c
    type(tuple) :: pos
  end type bag_data_type
end module ex5f90module

module ex5f90Bag_interface_module
  use ex5f90module

  interface PetscBagGetData
    subroutine PetscBagGetData(bag, data, ierr)
      use ex5f90module
      PetscBag bag
      type(bag_data_type), pointer :: data
      PetscErrorCode ierr
    end subroutine PetscBagGetData
  end interface
end module ex5f90Bag_interface_module

program ex5f90
  use ex5f90Bag_interface_module
  use petsc
  implicit none

  PetscBag bag
  PetscErrorCode ierr
  type(bag_data_type), pointer :: data
  type(bag_data_type)          :: dummydata
  character(len=1), pointer     :: dummychar(:)
  PetscViewer viewer
  PetscSizeT sizeofbag
  Character(len=99) list(6)
  PetscInt three, int56
  PetscReal value
  PetscScalar svalue

  PetscCallA(PetscInitialize(ierr))
  list(1) = 'a123'
  list(2) = 'b456'
  list(3) = 'c789'
  list(4) = 'list'
  list(5) = 'prefix_'
  list(6) = ''
!     cannot just pass a 3 to PetscBagRegisterXXXArray() because it is expecting a PetscInt
  three = 3

!   compute size of the data
!
  sizeofbag = size(transfer(dummydata, dummychar))

! create the bag
  PetscCallA(PetscBagCreate(PETSC_COMM_WORLD, sizeofbag, bag, ierr))
  PetscCallA(PetscBagGetData(bag, data, ierr))
  PetscCallA(PetscBagSetName(bag, 'demo parameters', 'super secret demo parameters in a bag', ierr))
  PetscCallA(PetscBagSetOptionsPrefix(bag, 'pbag_', ierr))

! register the data within the bag, grabbing values from the options database
!     Need to put the value into a variable for 64-bit indices
  int56 = 56
  PetscCallA(PetscBagRegisterInt(bag, data%nxc, int56, 'nxc', 'nxc_variable help message', ierr))
  PetscCallA(PetscBagRegisterRealArray(bag, data%rarray, three, 'rarray', 'rarray help message', ierr))
!     Need to put the value into a variable to pass correctly for 128 bit quad precision numbers
  svalue = 103.20
  PetscCallA(PetscBagRegisterScalar(bag, data%x, svalue, 'x', 'x variable help message', ierr))
  PetscCallA(PetscBagRegisterBool(bag, data%t, PETSC_TRUE, 't', 't boolean help message', ierr))
  PetscCallA(PetscBagRegisterBoolArray(bag, data%tarray, three, 'tarray', 'tarray help message', ierr))
  PetscCallA(PetscBagRegisterString(bag, data%c, 'hello', 'c', 'string help message', ierr))
  value = -11.00
  PetscCallA(PetscBagRegisterReal(bag, data%y, value, 'y', 'y variable help message', ierr))
  value = 1.00
  PetscCallA(PetscBagRegisterReal(bag, data%pos%x1, value, 'pos_x1', 'tuple value 1 help message', ierr))
  value = 2.00
  PetscCallA(PetscBagRegisterReal(bag, data%pos%x2, value, 'pos_x2', 'tuple value 2 help message', ierr))
  PetscCallA(PetscBagRegisterEnum(bag, data%enum, list, 1, 'enum', 'tuple value 2 help message', ierr))
  PetscCallA(PetscBagView(bag, PETSC_VIEWER_STDOUT_WORLD, ierr))

  data%nxc = 23
  data%rarray(1) = -1.0
  data%rarray(2) = -2.0
  data%rarray(3) = -3.0
  data%x = 155.4
  data%c = 'a whole new string'
  data%t = PETSC_TRUE
  data%tarray = (/PETSC_TRUE, PETSC_FALSE, PETSC_TRUE/)
  PetscCallA(PetscBagView(bag, PETSC_VIEWER_BINARY_WORLD, ierr))

  PetscCallA(PetscViewerBinaryOpen(PETSC_COMM_WORLD, 'binaryoutput', FILE_MODE_READ, viewer, ierr))
  PetscCallA(PetscBagLoad(viewer, bag, ierr))
  PetscCallA(PetscViewerDestroy(viewer, ierr))
  PetscCallA(PetscBagView(bag, PETSC_VIEWER_STDOUT_WORLD, ierr))

  PetscCallA(PetscBagSetFromOptions(bag, ierr))
  PetscCallA(PetscBagView(bag, PETSC_VIEWER_STDOUT_WORLD, ierr))
  PetscCallA(PetscBagDestroy(bag, ierr))

  PetscCallA(PetscFinalize(ierr))
end program ex5f90

!
!/*TEST
!
!   build:
!      requires: defined(PETSC_USING_F2003) defined(PETSC_USING_F90FREEFORM)
!
!   test:
!      args: -pbag_rarray 4,5,88
!
!TEST*/