/*
 * generated by Xtext 2.12.0
 */
package rba.tool.editor.ui.contentassist

import com.google.common.base.Predicate
import com.google.common.base.Predicates
import com.google.inject.Inject
import org.apache.log4j.Logger
import org.eclipse.emf.ecore.EObject
import org.eclipse.emf.ecore.util.EcoreUtil
import org.eclipse.jface.text.contentassist.ICompletionProposal
import org.eclipse.jface.viewers.StyledString
import org.eclipse.swt.graphics.Image
import org.eclipse.xtext.Assignment
import org.eclipse.xtext.CrossReference
import org.eclipse.xtext.Keyword
import org.eclipse.xtext.RuleCall
import org.eclipse.xtext.conversion.ValueConverterException
import org.eclipse.xtext.resource.IEObjectDescription
import org.eclipse.xtext.scoping.IScope
import org.eclipse.xtext.ui.editor.contentassist.AbstractJavaBasedContentProposalProvider.DefaultProposalCreator
import org.eclipse.xtext.ui.editor.contentassist.ConfigurableCompletionProposal
import org.eclipse.xtext.ui.editor.contentassist.ContentAssistContext
import org.eclipse.xtext.ui.editor.contentassist.ICompletionProposalAcceptor
import rba.core.Content
import rba.core.LambdaExpression
import rba.core.RBACorePackage
import rba.core.Variable
import rba.sound.SoundContent
import rba.sound.SoundContentSet
import rba.sound.Zone
import rba.sound.ZoneSet
import rba.tool.editor.resource.RBAModelEObjectDescription
import rba.tool.editor.ui.util.CharacterUtil
import rba.view.Area
import rba.view.AreaSet
import rba.view.Display
import rba.view.Size
import rba.view.ViewContent
import rba.view.ViewContentSet

/**
 * See https://www.eclipse.org/Xtext/documentation/304_ide_concepts.html#content-assist
 * on how to customize the content assistant.
 */
class RBAModelProposalProvider extends AbstractRBAModelProposalProvider {

	private final static Logger log = Logger.getLogger(RBAModelProposalProvider);

	@Inject RBAModelExpressionScopeCreator expressionScopeCreator;

	override completeKeyword(Keyword keyword, ContentAssistContext contentAssistContext, ICompletionProposalAcceptor acceptor) {
		if (!CharacterUtil.isKeywordWorthyToPropose(keyword)) {
			super.completeKeyword(keyword, contentAssistContext, acceptor)
		}
	}

	override lookupCrossReference(CrossReference crossReference, ContentAssistContext contentAssistContext, ICompletionProposalAcceptor acceptor) {
		lookupCrossReference(crossReference, contentAssistContext, acceptor, getFeatureDescriptionPredicate(crossReference, contentAssistContext));
	}

	def protected Predicate<IEObjectDescription> getFeatureDescriptionPredicate(CrossReference crossReference, ContentAssistContext contentAssistContext) {
		return Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				if (input.EObjectOrProxy instanceof Variable) {
					return contentAssistContext.currentModel.internalLambdaExpression(input.EObjectOrProxy);
				}

				if (input.EObjectOrProxy instanceof Size) {
					return isValidSizeModel(input.EObjectOrProxy, crossReference)
				}

				return true;
			}
		});
	}

	def private boolean isValidSizeModel(EObject objectOrProxy, CrossReference crossReference) {
		var EObject tmpObj
		if (objectOrProxy.eIsProxy) {
			// resolve proxy object with crossReference
			tmpObj = EcoreUtil.resolve(objectOrProxy, crossReference);
		} else {
			tmpObj = objectOrProxy
		}
		// get the container of the real object
		if (tmpObj instanceof Size) {
			if (!(tmpObj.eContainer instanceof Area) && !(tmpObj.eContainer instanceof Content) && !(tmpObj.eContainer instanceof Display)) {
				return true;
			}
		}
		return false;
	}

	def protected boolean internalLambdaExpression(EObject eObj1, EObject eObj2) {
		if (eObj1 === null || !(eObj2 instanceof Variable)) {
			return false;
		}

		if (eObj1 instanceof LambdaExpression && (eObj1 as LambdaExpression).x === eObj2) {
			return true;
		}

		return internalLambdaExpression(eObj1.eContainer, eObj2);
	}

	override protected getProposalFactory(String ruleName, ContentAssistContext contentAssistContext) {
		return new DefaultProposalCreator(contentAssistContext, ruleName, getQualifiedNameConverter()) {
			override apply(IEObjectDescription candidate) {
				if (candidate === null)
					return null;
				var ICompletionProposal result = null;
				var String proposal = qualifiedNameConverter.toString(candidate.getName());
				if (valueConverter !== null) {
					try {
						proposal = valueConverter.toString(proposal);
					} catch (ValueConverterException e) {
						log.debug(e.getMessage(), e);
						return null;
					}
				} else if (ruleName !== null) {
					try {
						proposal = getValueConverter().toString(proposal, ruleName);
					} catch (ValueConverterException e) {
						log.debug(e.getMessage(), e);
						return null;
					}
				}
				val EObject objectOrProxy = candidate.getEObjectOrProxy();
				val StyledString displayString = getStyledDisplayString(candidate);
				val Image image = getImage(candidate);
				result = createCompletionProposal(proposal, displayString, image, contentAssistContext);
				if (result instanceof ConfigurableCompletionProposal) {
					(result as ConfigurableCompletionProposal).setProposalContextResource(contentAssistContext.getResource());
					(result as ConfigurableCompletionProposal).setAdditionalProposalInfo(objectOrProxy);
					(result as ConfigurableCompletionProposal).setHover(hover);

					if (candidate instanceof RBAModelEObjectDescription) {
						(result as ConfigurableCompletionProposal).setCursorPosition((result as ConfigurableCompletionProposal).cursorPosition +
							(candidate as RBAModelEObjectDescription).getAdditionalInfo().get(0));
						(result as ConfigurableCompletionProposal).setPriority((result as ConfigurableCompletionProposal).priority +
							(candidate as RBAModelEObjectDescription).getAdditionalInfo().get(1));
					}
				}
				getPriorityHelper().adjustCrossReferencePriority(result, contentAssistContext.getPrefix());
				return result;
			}
		};
	}

	override completeAreaSet_Target(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof Area || input.EObjectOrProxy instanceof AreaSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeViewContentSet_Target(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof ViewContent || input.EObjectOrProxy instanceof ViewContentSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeViewContentSet_Allocatable(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof Area || input.EObjectOrProxy instanceof AreaSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeZoneSet_Target(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof Zone || input.EObjectOrProxy instanceof ZoneSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeSoundContentSet_Target(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof SoundContent || input.EObjectOrProxy instanceof SoundContentSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeSoundContentSet_Allocatable(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof Zone || input.EObjectOrProxy instanceof ZoneSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeViewContent_Allocatable(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof Area || input.EObjectOrProxy instanceof AreaSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeSoundContent_Allocatable(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val Predicate<IEObjectDescription> filter = Predicates.and(new Predicate<IEObjectDescription>() {
			override public boolean apply(IEObjectDescription input) {
				return (input.EObjectOrProxy instanceof Zone || input.EObjectOrProxy instanceof ZoneSet);
			}
		});
		lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor, filter);
	}

	override completeCMemberFeatureReference_RefObject(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		createMemberAndOperatorProposals(model, assignment, context, acceptor);
	}

	override completeVMemberFeatureReference_RefObject(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		createMemberAndOperatorProposals(model, assignment, context, acceptor);
	}

	def protected void createMemberAndOperatorProposals(EObject model, Assignment assignment, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val IScope scope = expressionScopeCreator.getExpressionScope(model, context);
		if (scope === null) {
			lookupCrossReference((assignment.getTerminal() as CrossReference), context, acceptor);
		} else {
			getCrossReferenceProposalCreator().lookupCrossReference(scope, model, RBACorePackage.Literals.OBJECT_REFERENCE__REF_OBJECT, acceptor,
				getFeatureDescriptionPredicate((assignment.getTerminal() as CrossReference), context), getProposalFactory("ValidID", context));
		}
	}

	override complete_OpGetProperty(EObject model, RuleCall ruleCall, ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
		val IScope scope = expressionScopeCreator.getExpressionScope(model, context);
		if (scope !== null) {
			getCrossReferenceProposalCreator().lookupCrossReference(scope, model, RBACorePackage.Literals.OPERATOR__OPERAND, acceptor, Predicates.<IEObjectDescription>alwaysTrue(),
				getProposalFactory(null, context));
		}
	}

}