grammar org.casualintellect.CasualIntellect with org.eclipse.xtext.common.Terminals

generate casualIntellect "http://www.casualintellect.org/CasualIntellect"

Model:
	list_of_states+=State+;

State:
	'state' name=ID '{' before=ProcessBeforeState after=ProcessAfterState? inProcess=ProcessInState transitions=Transitions? '}';

Transitions:
	'transitions' ':' '{' list+=Transition? (',' list+=Transition)* '}';

TransitionsList:
	transitions+=Transition (';' transitions+=Transition)*;

Transition:
	'transition' ':' name=ID ';' 'condition' ':' condition=Expression ';' ('methods' ':' methods+= ID (',' methods+=ID)*)?;

ProcessInState:
	'in_process' ':' methods+=ID? (',' methods+=ID)* ';';

ProcessAfterState:
	'after' ':' methods+=ID? (',' methods+=ID)* ';'; 

ProcessBeforeState:
	'before' ':' methods+=ID? (',' methods+=ID)* ';';

Expression:	Or;

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

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

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

Atomic returns Expression:
	{StringConstant} value=ID |
	{BoolConstant} value=('true' | 'false');

	

/*
 * generated by Xtext
 */
package org.casualintellect.generator

import java.util.List
import org.casualintellect.casualIntellect.And
import org.casualintellect.casualIntellect.BoolConstant
import org.casualintellect.casualIntellect.Expression
import org.casualintellect.casualIntellect.Not
import org.casualintellect.casualIntellect.Or
import org.casualintellect.casualIntellect.State
import org.casualintellect.casualIntellect.StringConstant
import org.eclipse.emf.ecore.resource.Resource
import org.eclipse.xtext.generator.IFileSystemAccess
import org.eclipse.xtext.generator.IGenerator

/**
 * Generates code from your model files on save.
 * 
 * see http://www.eclipse.org/Xtext/documentation.html#TutorialCodeGeneration
 */
class CasualIntellectGenerator implements IGenerator {

	override void doGenerate(Resource resource, IFileSystemAccess fsa) {
		var states = "";
		for (e : resource.allContents.toIterable.filter(typeof(State))) {
			states = states + e.compile;
			states = states + "\n"
		}
		fsa.generateFile("states/states" + ".xml", states)
	}

	def compile(State state) {
		'''<state name="«state.name»">
	<before methods="«if(state.before != null) processMethodsList(state.before.methods)»"/>
	<after methods="«if(state.after != null) processMethodsList(state.after.methods)»"/>	
	<in_process methods="«if(state.inProcess != null) processMethodsList(state.inProcess.methods)»"/>
	<transitions>«IF (state.transitions != null)»
		«FOR transition : state.transitions.list»
			<transition>
				«FOR method : transition.methods»
				<method>«method»</method>
				«ENDFOR»
				<condition function="«transition.condition.compile»"/>
			</transition>
		«ENDFOR»
	«ENDIF»</transitions>
</state>'''
	}

	def compile(Expression expression) {
		switch (expression) {
			Or: {

				compile(expression.left) + ' || ' + compile(expression.right);
			}
			And: {
				compile(expression.left) + ' && ' + compile(expression.right);
			}
			Not: expression.expression.compile
			
			BoolConstant:
				Boolean::parseBoolean(expression.value)
			StringConstant:
				expression.value
		}
	}

	def processMethodsList(List<String> methods) {
		var methodsStr = "";
		for (var i = 0; i < methods.length; i++) {
			methodsStr = methodsStr + methods.get(i);
			if (i < methods.length - 1) {
				methodsStr += ',';
			}
		}
		methodsStr;
	}
}

@Test
def void testWithBrackets() {

		'''state state1{
			before: salo, pivo, vodka;
		    after:salo,pivo,vodka; 
		    in_process:pivo, vodka, salo; 
		    transitions: {transition:salo; condition:(f1 || f2)&&!false;} 
		  }'''.
			assertCompilesTo(
				'''<state name="state1">
	<before methods="salo,pivo,vodka"/>
	<after methods="salo,pivo,vodka"/>	
	<in_process methods="pivo,vodka,salo"/>
	<transitions>
	<transition>
		<condition function="(f1 || f2) && false"/>
	</transition>
	</transitions>
</state>
''')
	}