package org.simantics.scl.compiler.elaboration.expressions;


import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
import org.simantics.scl.compiler.common.names.Names;
import org.simantics.scl.compiler.constants.DoubleConstant;
import org.simantics.scl.compiler.constants.FloatConstant;
import org.simantics.scl.compiler.constants.IntegerConstant;
import org.simantics.scl.compiler.constants.LongConstant;
import org.simantics.scl.compiler.elaboration.contexts.ReplaceContext;
import org.simantics.scl.compiler.elaboration.contexts.SimplificationContext;
import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;
import org.simantics.scl.compiler.elaboration.contexts.TypingContext;
import org.simantics.scl.compiler.errors.Locations;
import org.simantics.scl.compiler.types.Type;
import org.simantics.scl.compiler.types.Types;
import org.simantics.scl.compiler.types.exceptions.MatchException;

import gnu.trove.map.hash.TObjectIntHashMap;
import gnu.trove.set.hash.TIntHashSet;

public class EIntegerLiteral extends SimplifiableExpression {
    public String value;
    public EVariable constraint;

    public EIntegerLiteral(String value) {
        this.value = value;
    }

    @Override
    public void collectVars(TObjectIntHashMap<Variable> allVars,
            TIntHashSet vars) {
    }
    
    public String getValue() {
        return value;
    }
    
    private Expression tryToConvertToPrimitive(Type requiredType) {
        if(requiredType.equals(Types.INTEGER))
            return new ELiteral(new IntegerConstant(Integer.parseInt(value)));
        else if(requiredType.equals(Types.DOUBLE))
            return new ELiteral(new DoubleConstant(Double.parseDouble(value)));
        else if(requiredType.equals(Types.FLOAT))
            return new ELiteral(new FloatConstant(Float.parseFloat(value)));
        else if(requiredType.equals(Types.LONG))
            return new ELiteral(new LongConstant(Long.parseLong(value)));
        else
            return null;
    }
    
    @Override
    public Expression checkBasicType(TypingContext context, Type requiredType) {
        requiredType = Types.canonical(requiredType);
        
        try {
            Expression primitive = tryToConvertToPrimitive(requiredType);
            if(primitive != null)
                return primitive;
        } catch(NumberFormatException e) {
            context.getErrorLog().log(getLocation(), "Invalid number format.");
        }
        
        setType(requiredType);
        constraint = new EVariable(location, null);
        constraint.setType(Types.pred(Types.RING, requiredType));
        context.addConstraintDemand(constraint);
        return this;        
    }
    
    @Override
    protected void updateType() throws MatchException {
        throw new InternalCompilerError();
    }

    @Override
    public Expression simplify(SimplificationContext context) {
        try {
            Expression primitive = tryToConvertToPrimitive(Types.canonical(getType()));
            if(primitive != null)
                return primitive;
            return context.apply(
                    context.getConstant(Names.Prelude_fromInteger, getType()),
                    constraint.simplify(context),
                    context.literal(new IntegerConstant(Integer.parseInt(value)))
                    );
        } catch(NumberFormatException e) {
            context.getErrorLog().log(getLocation(), "Invalid number format (maybe too long for the expected number type).");
            return this;
        }
    }

    @Override
    public Expression resolve(TranslationContext context) {
        return this;
    }
    
    @Override
    public Expression resolveAsPattern(TranslationContext context) {
        return this;
    }
    
    @Override
    public Expression replace(ReplaceContext context) {
        EIntegerLiteral copy = new EIntegerLiteral(value);
        copy.setType(getType().replace(context.tvarMap));
        copy.constraint = (EVariable)constraint.replace(context);
        return copy;
    }
    
    @Override
    public boolean isEffectful() {
    	return false;
    }
    
    @Override
    public void setLocationDeep(long loc) {
        if(location == Locations.NO_LOCATION) {
            location = loc;
            if(constraint != null)
                constraint.setLocationDeep(loc);
        }
    }
    
    @Override
    public void accept(ExpressionVisitor visitor) {
        visitor.visit(this);
    }
    
    @Override
    public boolean isPattern(int arity) {
        return arity == 0;
    }
    
    @Override
    public Expression accept(ExpressionTransformer transformer) {
        return transformer.transform(this);
    }

}