##DESCRIPTION
##  Lewis Structures
##ENDDESCRIPTION

##KEYWORDS('lewis structures')

## Date('3/5/2023')
## Author('Lee McPherson')
## Institution('Portland Community College')


########################################################################

DOCUMENT();

loadMacros(
   "PGstandard.pl",     # Standard macros for PG language
   "MathObjects.pl",
   "PGML.pl",
   "parserLewisStructureTool.pl"
);

##############################################################

@moleculeFormulaLatex = ('NH_3','N_2', 'CH_4', 'CCl_4', 'PON', 'C_2H_6', 'C_2H_4', 'SF_6', 'SF_4', 'XeF_4', 'C_3H_8', 'C_4H_10', 'N_2O', 'O_3', 'SO_4^{2-}', 'NO_3^-');
#$rand_num_generator = new PGrandom();
#$index = random(0,scalar @moleculeFormulaLatex,1);
$index = 1;  # in case you don't want to make it random...

$formula = $moleculeFormulaLatex[$index];
$lewisStructure = LewisStructureTool($formula)->with(cmpOptions => {'debug'=> 1,'showFormalCharges'=> 0, 'formalChargePenalty'=>0.4, 'requirePerspective'=>0});
# With optional parameters for grading.
# $lewisStructure = LewisStructureTool($formula)->with(cmpOptions => { "bondOrderPenalty" => 0.333 } );

##############################################################
#
#  Problem
#
BEGIN_PGML
Draw the structure for [`\mathrm{[$formula]}`] in the box below:

[@ LABELED_ANS($lewisStructure->ANS_NAME, $lewisStructure->cmp); $lewisStructure->ans_rule @]*




END_PGML
#[____]{$lewisStructure}
#
BEGIN_PGML_SOLUTION

[@ $lewisStructure->showSolutionGuide() @]*

END_PGML_SOLUTION

ENDDOCUMENT();