package org.simantics.scl.compiler.module;

import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.Function;

import org.simantics.scl.compiler.constants.Constant;
import org.simantics.scl.compiler.elaboration.chr.CHRRuleset;
import org.simantics.scl.compiler.elaboration.modules.Documentation;
import org.simantics.scl.compiler.elaboration.modules.SCLValue;
import org.simantics.scl.compiler.elaboration.modules.TypeClass;
import org.simantics.scl.compiler.elaboration.modules.TypeClassInstance;
import org.simantics.scl.compiler.elaboration.modules.TypeDescriptor;
import org.simantics.scl.compiler.elaboration.relations.SCLEntityType;
import org.simantics.scl.compiler.elaboration.relations.SCLRelation;
import org.simantics.scl.compiler.elaboration.rules.MappingRelation;
import org.simantics.scl.compiler.elaboration.rules.TransformationRule;
import org.simantics.scl.compiler.errors.CompilationError;
import org.simantics.scl.compiler.internal.codegen.effects.EffectConstructor;
import org.simantics.scl.compiler.top.ModuleInitializer;
import org.simantics.scl.compiler.types.TCon;
import org.simantics.scl.runtime.profiling.BranchPoint;

import gnu.trove.map.hash.THashMap;

public abstract class LazyModule implements Module {

    private final String moduleName;
    private final ConcurrentHashMap<String, SCLValue> values = new ConcurrentHashMap<String, SCLValue>();
    private final ConcurrentHashMap<String, SCLRelation> relations = new ConcurrentHashMap<String, SCLRelation>();
    private final ConcurrentHashMap<String, SCLEntityType> entityTypes = new ConcurrentHashMap<String, SCLEntityType>();
    
    protected abstract SCLValue createValue(String name);
    
    protected SCLRelation createRelation(String name) {
        return null;
    }
    
    protected SCLEntityType createEntityType(String name) {
        return null;
    }
    
    @Override
    public MappingRelation getMappingRelation(String name) {
        return null;
    }
    
    @Override
    public TransformationRule getRule(String name) {
        return null;
    }
    
    public LazyModule(String moduleName) {
        this.moduleName = moduleName;
    }
        
    @Override
    public String getName() {
        return moduleName;
    }
    
    public void findValuesForPrefix(final Collection<SCLValue> values, final String prefix) {    	
    }

    private final Function<String, SCLValue> createValue = this::createValue;
    
    @Override
    public SCLValue getValue(String name) {
        return values.computeIfAbsent(name, createValue);
    }
    
    @Override
    public List<Constant> getFieldAccessors(String name) {
        return null;
    }
    
    private final Function<String, SCLRelation> createRelation = this::createRelation;
    
    public SCLRelation getRelation(String name) {
        return relations.computeIfAbsent(name, createRelation);
    }
    
    private final Function<String, SCLEntityType> createEntityType = this::createEntityType;
    
    public SCLEntityType getEntityType(String name) {
        return entityTypes.computeIfAbsent(name, createEntityType);
    } 

    @Override
    public TypeClass getTypeClass(String name) {
        return null;
    }
   
    @Override
    public Collection<TypeClassInstance> getInstances(TCon typeClass) {
        return Collections.emptyList();
    }

    @Override
    public TypeDescriptor getTypeDescriptor(String name) {
        return null;
    }

    @Override
    public Documentation getDocumentation() {
        return null;
    }
    
    @Override
    public byte[] getClass(String name) {
        return null;
    }
    
    @Override
    public ModuleInitializer getModuleInitializer() {
        return null;
    }
    
    @Override
    public EffectConstructor getEffectConstructor(String name) {
        return null;
    }
    
    @Override
    public Collection<TransformationRule> getRules() {
        return Collections.emptyList();
    }
    
    @Override
    public THashMap<String, BranchPoint[]> getBranchPoints() {
        return null;
    }
    
    @Override
    public CompilationError[] getWarnings() {
        return CompilationError.EMPTY_ARRAY;
    }
    
    @Override
    public CHRRuleset getRuleset(String name) {
        return null;
    }
    
    @Override
    public String getDeprecation() {
        return null;
    }
}