grammar com.septentrio.infrastructure.flax.Flax with org.eclipse.xtext.common.Terminals

generate language "http://www.septentrio.com/infrastructure/flax/Flax"

Flax:
    ('package' name=QualifiedName)?
    (imports+=Import)*
    (entities+=Entity)*;

Import:
    'import' importedNamespace=QualifiedNameWithWildcard;

QualifiedName:
    ID ('.' ID)*;

QualifiedNameWithWildcard:
    QualifiedName '.*'?;

Entity:
    Tag|Class;

Tag:
    'tag' name=ID
    ( '{' properties+=TagProperty* '}' )?;

TagProperty:
    name=ID;

Class:
    tagrefs+=TagReference*
	'class' name=ID
	( 'extends' (parents+=[Class|QualifiedName]','?)+ )?
	( '{' sections+=Section* '}' )?;

TagReference:
    '@' tag=[Tag]
    ( '(' ( arguments+=[TagProperty|QualifiedName] ','? )* ')' )?;

Section:
    PropertySection|MethodSection;

PropertySection:
    'properties' '{' properties+=Property* '}';

MethodSection:
    'methods' '{' methods+=Method* '}';

Member:
    Property|Method;

Property:
	type=ElementType name=ID;

Method:
    type=ElementType? name=ID
    ( '(' (parameters+=Parameter','?)* ')' )?
    body=Block;

Block:
    '{' (expressions+=Expression)* '}';

ElementType:
	BasicType|ClassType;

BasicType:
	type=('void'|'any'|'enum'|'logical'|'string'|'integer'|'float');

ClassType:
	type=[Class|QualifiedName];

Parameter:
    type=ElementType name=ID;

Symbol:
    Entity|Parameter|Member;

Expression:
    Primary ( {Selection.operand=current} levels+=SelectionLevel )*;

Primary returns Expression:
    '(' Expression ')' |
    {Boolean} value=('true'|'false') |
    {Integer} value=INT |
    {SymbolReference} symbol=[Symbol] => Parameters? |
    {Metadata} '?' name=ID;

SelectionLevel returns Expression:
    {MemberSelection} '.' name=[Member] => Parameters?;

fragment Parameters:
    parameterized ?= '(' (parameters+=Expression','?)* ')';

@Check
def duplicateArgument(TagReference t) {
	val visited = <TagProperty>newArrayList
	for (argument: t.arguments)
		if (visited.contains(argument))
			error(
					'''Duplicate argument "«argument.name»" for tag "«t.tag.name»" for class "«t.getContainerOfType(Class).name»"''',
					LanguagePackage.Literals.TAG_REFERENCE__ARGUMENTS,
					DUPLICATE_ELEMENT
			)
		else
			visited.add(argument)
}

tag Animal {
    Running
    Sleeping
}

@Animal(Running, Sleeping, Sleeping)
class Horse

@Test
def void testDuplicateClassTagReferenceArgument() {
	'''
	tag Tool {
		Powered
		Colored
	}
	@Tool(Colored, Powered, Powered)
	class Lamp
	''' => [
		parse
		.assertError(
				LanguagePackage.Literals.TAG_REFERENCE,
				FlaxValidator.DUPLICATE_ELEMENT,
				StringUtils.ordinalIndexOf(it, 'Powered', 2),
				'Powered'.length,
				'Duplicate argument "Powered" for tag "Tool" for class "Lamp"'
		)
	]
}