#ifdef PASS_PRE1
#define _AND_ &&
#define _OR_ ||
#define _NOT_ !
#define IS_INNER_LAYER (_NOT_ (IS_BOTTOM_LEVEL _OR_ IS_TOP_LAYER))
#define IS_INNER_INTERFACE (_NOT_ (IS_BOTTOM_LEVEL _OR_ IS_TOP_INTERFACE))
#endif

#ifdef PASS_PRE2

#define BARRIER !$OMP BARRIER
#define IS_INNER_INTERFACE (.NOT. (IS_BOTTOM_LEVEL .OR. IS_TOP_INTERFACE))
#define KERNEL(name) {% call() define_kernel(#name) %}
#define FORALL_CELLS(...) {% call(lrange,flags) forall_cells(__VA_ARGS__) %}
#define FORALL_CELLS_EXT(...) {% call(lrange,flags) forall_cells(__VA_ARGS__) %}
#define ON_PRIMAL {% call(mesh, degree=0) on_mesh('primal',lrange,flags) %}
#define ON_DUAL {% call(mesh, degree=0) on_mesh('dual',lrange,flags) %}
#define ON_EDGES {% call(mesh, degree=0) on_edges('edge',lrange,flags) %}
#define FORALL_EDGES {% call forall_edges(mesh,degree) %}
#define FORALL_VERTICES {% call forall_vertices(mesh,degree) %}
#define FORALL_TRISK {% call forall_trisk(degree) %}
#define END_BLOCK {% endcall %}
#define SEQUENCE {% call sequence() %} 
#define SEQUENCE_EXT {% call sequence() %} 
#define PROLOGUE(level) {% call at_level(level) %}
#define EPILOGUE(level) {% call at_level(level) %}
#define BODY(range) {% call(cell_up,cell_down) body(range) %}

#define CST_IF(condition, action) {{ cst_if(#condition, #action) }}
#define CST_IFTHEN(condition) {{flat}}if condition
#define CST_ELSEIF(condition) {{flat}}elif condition
#define CST_ELSE {{flat}}else
#define CST_ENDIF {{flat}}endif

#endif

#ifdef PASS_JINJA

{#  -------------------------- Design notes ------------------------------

The syntax 
{% call(ARGNAMES) macro(ARGS) %}
...
{% endcall %}
passes ARGS to macro ; this macro "calls" the body using the syntax 'caller(arg1,...)' ; these arguments
are available in the body under the names ARGNAMES, as if it were a macro caller(ARGNAMES).

Using its optional argument 'options', forall_cells() sets variable 'flags' 
and passes it on to on_mesh() / on_edges()

Similarly variable 'lrange' is passed from forall_cells to on_mesh() / on_egdes()  

-------------------------------------------------------------------------- #}


{# ----------------------- SEQUENCE, FORALL ----------------------- #}

{% macro sequence() -%}
  
!$OMP DO SCHEDULE(STATIC)                                                                            
  DO ij=1,primal_num
    {{ caller() }}
  END DO
!$OMP END DO

{%- endmacro %}

{% macro body(range) -%}
  {{ define('CELL','l,ij') }}
    DO l = {{ range }}
      {{ caller() }}
    END DO
  {{ undef('CELL') }}
{%- endmacro %}

{% macro at_level(lev) -%}
  {{ define('CELL','l,ij') }}
  l={{ lev }}
  {{ caller() }}
  {{ undef('CELL') }}
{%- endmacro %}

{% macro forall_cells(start='1', end='llm', options=[]) -%}
  {% set flags=[options] if options is string else options %}
  {{ caller((start,end),flags) }}
{%- endmacro %}

{# ------------------------------ MESHES --------------------------- #}

{# argument 'code' is the body enclosed by ON_XXX ... END_BLOCK ; it takes arguments : mesh,degree=0 #}

{% macro vloop_unroll(mesh, lrange, flags, code) %}

{% set thecode, has_primal, has_dual, has_trisk, has_none = code(mesh), False, False, False, True %}

{% if 'primal_deg' in thecode %}
! this VLOOP iterates over primal cell edges
{% set has_primal, has_none = True,False %}
{% endif %}
{% if 'dual_deg' in thecode %}
! this VLOOP iterates over dual cell edges
{% set has_dual,has_none = True,False %}
{% endif %}
{% if 'trisk_deg' in thecode %}
! this VLOOP iterates over the TRISK stencil
{% set has_trisk,has_none = True,False %}
{% endif %}

{% if has_none %}
{{ vloop(mesh, lrange, flags, code) }}
{% endif %}

{% if has_primal %}
SELECT CASE(primal_deg(ij))
CASE(4)
{{ vloop(mesh, lrange, flags, code, 4) }}
CASE(5)
{{ vloop(mesh, lrange, flags, code, 5) }}
CASE(6)
{{ vloop(mesh, lrange, flags, code, 6) }}
CASE DEFAULT
{{ vloop(mesh, lrange, flags, code) }}
END SELECT
{% endif %}

{% if has_dual %}
SELECT CASE(dual_deg(ij))
CASE(3)
{{ vloop(mesh, lrange, flags, code, 3) }}
CASE(4)
{{ vloop(mesh, lrange, flags, code, 4) }}
CASE DEFAULT
{{ vloop(mesh, lrange, flags, code) }}
END SELECT
{% endif %}

{% if has_trisk %}
SELECT CASE(trisk_deg(edge))
CASE(10)
{{ vloop(mesh, lrange, flags, code, 10) }}
CASE(4)
{{ vloop(mesh, lrange, flags, code, 4) }}
CASE DEFAULT
{{ vloop(mesh, lrange, flags, code) }}
END SELECT
{% endif %}

{%- endmacro %}

{% macro vloop(mesh, lrange, flags, code, degree=0) %}

{% set start,end = lrange %}
{% set thecode, is_top_layer, is_top_inter = code(mesh,degree), False, False %}

{{ define('IS_TOP_LAYER', '_FALSE_') }}
{{ define('IS_TOP_INTERFACE', '_FALSE_') }}

{% if 'IS_BOTTOM_LEVEL' in thecode or 'KDOWN' in thecode%}
{# the code in the loop checks whether l==1, for the sake of performance 
we shall write special code for l=1 and start the loop at l=2 #}
{{ define('IS_BOTTOM_LEVEL', '_TRUE_') }}
{{ 'kdown = 1' if 'KDOWN' in thecode }}
{{ 'kup   = 1' if 'KUP'   in thecode }}
l=1
{{ thecode }}
{% set start='2' %}
{% endif %}

{% if 'IS_TOP_LAYER' in thecode %}
{{ 'ERROR : using IS_TOP_LAYER in a loop ending at l=llm+1' if end=='llm+1' }}
{# the code checks whether l==llm, write special code for l=llm and end the loop at l=llm-1 #}
{% set end, is_top_layer = 'llm-1', True %}
{% endif %}

{% if 'IS_TOP_INTERFACE' in thecode or 'KUP' in thecode %}
{# the code checks whether l==llm+1, write special code for l=llm+1 and end the loop at l=llm #}
{{ 'ERROR : using IS_TOP_INTERFACE in a loop ending at l=llm' if end=='llm' }}
{% set end, is_top_inter ='llm', True %}
{% endif %}

{{ define('IS_BOTTOM_LEVEL', '_FALSE_') }}
  DO l = {{start}}, {{end}}
    {{ 'kdown = l-1' if 'KDOWN' in thecode }}
    {{ 'kup   = l' if 'KUP'   in thecode }}
    {{ thecode }}
  END DO

{% if is_top_layer %}
{{ define('IS_TOP_LAYER', '_TRUE_') }}
{{ 'kdown = llm-1' if 'KDOWN' in thecode }}
{{ 'kup   = llm' if 'KUP'   in thecode }}
l=llm
{{ thecode }}
{% endif %}

{% if is_top_inter %}
{{ define('IS_TOP_INTERFACE', '_TRUE_') }}
{{ 'kdown = llm' if 'KDOWN' in thecode }}
{{ 'kup   = llm' if 'KUP'   in thecode }}
l=llm+1
{{ thecode }}
{% endif %}

{% endmacro %}

{% macro on_mesh(mesh,lrange,flags) -%}
{{ define('CELL','l,ij') if mesh=='primal' }}
{{ define('DUAL_CELL', 'l,ij') if mesh=='dual'}}
!$OMP DO SCHEDULE(STATIC)                                                                            
DO ij = 1, {{ mesh }}_num
{{ vloop_unroll(mesh, lrange, flags, caller) }}
END DO
!$OMP END DO
{{ undef('CELL') }}
{{ undef('DUAL_CELL') }}
{%- endmacro %}

{# ------------------------------ STENCILS --------------------------- #}

{% macro on_edges(mesh,lrange,flags) -%}
{% set thecode = caller(mesh) %}
{{ define('EDGE', 'l,edge') }}
{{ define('LE_DE', 'le_de(edge)') }}
{{ define('SIGN', '1.') }}
{{ define('CELL1', 'l,ij_left') }}
{{ define('CELL2',  'l,ij_right') }}
{{ define('VERTEX1', 'l,ij_down') }}
{{ define('VERTEX2', 'l,ij_up') }}
!$OMP DO SCHEDULE(STATIC)
DO edge = 1, edge_num
{{ 'ij_left = left(edge)'   if 'CELL1'    in thecode }}
{{ 'ij_right = right(edge)' if 'CELL2'   in thecode }}
{{ 'ij_up = up(edge)'       if 'VERTEX1' in thecode }}
{{ 'ij_down = down(edge)'   if 'VERTEX2' in thecode }}
{{ vloop_unroll(mesh, lrange, flags, caller) }}
END DO
!$OMP END DO
{{ undef('EDGE') }}
{{ undef('LE_DE') }}
{{ undef('SIGN') }}
{{ undef('CELL1') }}
{{ undef('CELL2') }}
{{ undef('VERTEX1') }}
{{ undef('VERTEX2') }}
{%- endmacro %}

{% macro forall_edges(mesh,degree) -%}
{% set thecode = caller() %}
{{ define('EDGE', 'l,edge') }}
{{ define('VERTEX1', 'l,ij_down') }}
{{ define('VERTEX2', 'l,ij_up') }}
{{ define('SIGN', mesh + '_ne(iedge,ij)') }}
{{ define('LE_DE', 'le_de(edge)') }}

{% if degree>1 %}
{% for iedge in range(1,degree+1) %}
  iedge = {{ iedge }}
  edge = {{ mesh }}_edge({{ iedge }},ij)
  {{ 'ij_up = up(edge)'       if 'VERTEX1' in thecode }}
  {{ 'ij_down = down(edge)'   if 'VERTEX2' in thecode }}
  {{ thecode }}
{% endfor %}
{% else %}
DO iedge = 1, {{ mesh }}_deg(ij)
  edge = {{ mesh }}_edge(iedge,ij)
  {{ 'ij_up = up(edge)'       if 'VERTEX1' in thecode }}
  {{ 'ij_down = down(edge)'   if 'VERTEX2' in thecode }}
  {{ thecode }}
END DO
{% endif %}

{{ undef('EDGE') }}
{{ undef('SIGN') }}
{{ undef('LE_DE') }}
{%- endmacro %}

{% macro forall_trisk(degree) -%}
{% set thecode = caller() %}
{{ define('EDGE_TRISK', 'l,edge_trisk') }}
{% if degree>1 %}
{% for itrisk in range(1,degree+1) %}
  edge_trisk = trisk({{ itrisk }},edge)
  {{ thecode }}
{% endfor %}
{% else %}
DO itrisk = 1, trisk_deg(edge)
  edge_trisk = trisk(itrisk,edge)
  {{ thecode }}
END DO
{% endif %}
{{ undef('EDGE_TRISK') }}
{%- endmacro %}

{% macro forall_vertices(mesh,degree) -%}
{% set thecode = caller() %}
{{ define('VERTEX', 'l,vertex') }}
{% if degree>1 %}
{% for ivertex in range(1,degree+1) %}
  ivertex = {{ ivertex }}
  vertex = {{ mesh }}_vertex({{ ivertex }},ij) 
  {{ thecode }}
{% endfor %}
{% else %}
DO ivertex = 1, {{ mesh }}_deg(ij)
  vertex = {{ mesh }}_vertex(ivertex,ij)
  {{ thecode }}
END DO
{% endif %}
{{ undef('VERTEX') }}
{%- endmacro %}

{# --------------------------------------------------------- #}

{% set llm='llm' %}

{{ undef('SIGN') }}
{{ undef('CELL') }}
{{ undef('CELL1') }}
{{ undef('CELL2') }}
{{ undef('VERTEX1') }}
{{ undef('VERTEX2') }}
{{ undef('EDGE_TRISK') }}

{# --------------------- END JINJA ------------------------- #}

#endif

#ifdef PASS_POST1

#define _TRUE_ (0==0)
#define _FALSE_ (0==1)

#define RIV2 Riv2(ivertex,ij)
#define AI Ai(ij)
#define AV Av(ij)
#define FV fv(ij)
#define WEE wee(itrisk,edge)
#define edge_ne(iedge,ij) 1.
#endif

#ifdef PASS_POST2
#define KUP(l,ij) kup,ij
#define KDOWN(l,ij) kdown,ij
#define DOWN(l,ij) l-1,ij
#define UP(l,ij) l+1,ij
#define HIDX(l,ij) ij
#define VIDX(l,ij) l
#endif