Atomic returns Expression:
	{IntConstant} value=INT |
	{StringConstant} value=STRING |
	{BoolConstant} value=('true' | 'false') |
	{VariableRef} value=[VariableDeclaration];

Atomic returns Expression:
	{IntConstant} value=INT |
	{StringConstant} value=STRING |
	{BoolConstant} value=('true' | 'false') |
	{VariableRef} value=[VariableDeclaration]|
       {ClassMemberRef} value=[ClassDefinition.member];

grammar org.blockchain.rell.Rell with org.eclipse.xtext.common.Terminals

generate rell "http://www.blockchain.org/rell/Rell"

Model:
	entities+=ClassDefinition*
	operations+=Operation*;

ClassDefinition:
	'class' name=ID ('extends' superType=[ClassDefinition])? '{'
	attributes+=Attribute*
	'}';

Operation:
	"operation" name=ID "(" parameters=RelAttrubutesList? ")" "{" statements+=Statement* "}";

Statement:
	( relation=Relational |  variable=Variable | varInit=VariableInit) ';';

Variable:
	declaration=VariableDeclaration (('=' expression=Expression)?);

Relational:
	Update | Delete | Create;

Update:
	'update' entity=[ClassDefinition] '(' conditions=Conditions? ')' '{' variableList+=UpdateVariableInit
	(',' variableList+=UpdateVariableInit*)? '}';


Delete:
	'delete' entity=[ClassDefinition] '(' conditions=Conditions? ')';

Create:
	'create' entity=[ClassDefinition] '(' conditions=Conditions? ')';

Conditions:
	elements+=ConditionElement (',' elements+=ConditionElement*)?;

ConditionElement:
	name=ID ('==' | '!=' | '>' | '<' | '>=' | '<=') expr=Expression;

VariableInit:
	name=[VariableDeclaration] '=' expression=Expression;

UpdateVariableInit:
	name = ID '=' expression=Expression
;
Expression:
	or=Or;

Or returns Expression:
	And ({Or.left=current} "or" right=And)*;

And returns Expression:
	Equality ({And.left=current} "and" right=Equality)*;

Equality returns Expression:
	Comparison ({Equality.left=current} op=("==" | "!=")
	right=Comparison)*;

Comparison returns Expression:
	PlusOrMinus ({Comparison.left=current} op=(">=" | "<=" | ">" | "<")
	right=PlusOrMinus)*;

PlusOrMinus returns Expression:
	MulOrDiv (({Plus.left=current} '+' | {Minus.left=current} '-')
	right=MulOrDiv)*;

Atomic returns Expression:
	{IntConstant} value=INT |
	{StringConstant} value=STRING |
	{BoolConstant} value=('true' | 'false') |
	{VariableRef} value=[VariableDeclaration];

MulOrDiv returns Expression:
	Primary ({MulOrDiv.left=current} op=('*' | '/')
	right=Primary)*;

Primary returns Expression:
	'(' Expression ')' |
	{Not} "not" expression=Primary |
	Atomic;

RelAttrubutesList:
	value+=VariableDeclaration (',' value+=VariableDeclaration)*;

Attribute:
	modificator=Prefix? variable=VariableDeclaration ';';

VariableDeclaration:
	name=ID ':' type=TypeReference;

TypeReference:
	primitive=PrimitiveType | entityType=ClassType;

PrimitiveType:
	primitiveType=(Text | Integer | Json | ByteArray | Boolean);

ClassType:
	entityRef=[ClassDefinition];

Boolean:
	'bool';

Json:
	'json';

Integer:
	'integer' | 'timestamp';

Text:
	'text' | 'tuid' | 'name';

ByteArray:
	'byte_array' | 'signer' | 'guid' | 'pubkey';

Prefix:
	'key' | 'index';