IO.java

/*******************************************************************************
 * Copyright (c) 2009-2013 CWI All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License v1.0 which accompanies this
 * distribution, and is available at http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 * 
 * * Jurgen J. Vinju - Jurgen.Vinju@cwi.nl - CWI 
 * * Mark Hills - Mark.Hills@cwi.nl (CWI) 
 * * Arnold - Lankamp - Arnold.Lankamp@cwi.nl 
 * * Bert Lisser - Bert.Lisser@cwi.nl
 *******************************************************************************/
package org.rascalmpl.library.lang.json;

import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.nio.charset.Charset;
import java.util.Map;
import java.util.stream.Collectors;
import org.rascalmpl.debug.IRascalMonitor;
import org.rascalmpl.exceptions.RuntimeExceptionFactory;
import org.rascalmpl.library.lang.json.internal.JsonValueReader;
import org.rascalmpl.library.lang.json.internal.JsonValueWriter;
import org.rascalmpl.types.ReifiedType;
import org.rascalmpl.types.TypeReifier;
import org.rascalmpl.uri.URIResolverRegistry;
import org.rascalmpl.values.IRascalValueFactory;
import org.rascalmpl.values.functions.IFunction;

import io.usethesource.vallang.IBool;
import io.usethesource.vallang.IConstructor;
import io.usethesource.vallang.IInteger;
import io.usethesource.vallang.IMap;
import io.usethesource.vallang.ISourceLocation;
import io.usethesource.vallang.IString;
import io.usethesource.vallang.ITuple;
import io.usethesource.vallang.IValue;
import io.usethesource.vallang.type.Type;
import io.usethesource.vallang.type.TypeStore;

import com.google.gson.stream.JsonWriter;

public class IO {
    private final IRascalValueFactory values;
    private final IRascalMonitor monitor;

    public IO(IRascalValueFactory values, IRascalMonitor monitor) {
        super();
        this.values = values;
        this.monitor = monitor;
    }

    private IValue doReadJSON(Reader in, 
        IValue type, ISourceLocation loc, IString dateTimeFormat, IBool lenient, IBool trackOrigins,
        IFunction parsers, IMap nulls, IBool explicitConstructorNames, IBool explicitDataTypes) throws IOException {

        TypeStore store = new TypeStore();
        Type start = new TypeReifier(values).valueToType((IConstructor) type, store);
        
        if (parsers.getType() instanceof ReifiedType && parsers.getType().getTypeParameters().getFieldType(0).isTop()) {
            // ignore the default parser
            parsers = null;
        }

        try {
            return new JsonValueReader(values, store, monitor, loc)
                    .setCalendarFormat(dateTimeFormat.getValue())
                    .setLenient(lenient.getValue())
                    .setParsers(parsers) 
                    .setNulls(unreify(nulls))
                    .setExplicitConstructorNames(explicitConstructorNames.getValue())
                    .setExplicitDataTypes(explicitDataTypes.getValue())
                    .setTrackOrigins(trackOrigins.getValue())
                    .read(in, start);
        }
        catch (NullPointerException e) {
            throw RuntimeExceptionFactory.io("NPE in error handling code");
        }
    }
        
    public IValue readJSON(
        IValue type, ISourceLocation loc, IString dateTimeFormat, IBool lenient, IBool trackOrigins,
        IFunction parsers, IMap nulls, IBool explicitConstructorNames, IBool explicitDataTypes) {

        try (Reader in = URIResolverRegistry.getInstance().getCharacterReader(loc)) {
            return doReadJSON(in, type, loc, dateTimeFormat, lenient, trackOrigins, parsers, nulls, explicitConstructorNames, explicitDataTypes);
        }
        catch (IOException e) {
            throw RuntimeExceptionFactory.io(e);
        }
    }

    public IValue parseJSON(IValue type, IString src, IString dateTimeFormat, IBool lenient, IBool trackOrigins,
        IFunction parsers, IMap nulls, IBool explicitConstructorNames, IBool explicitDataTypes) {
       
        try (Reader in = new StringReader(src.getValue())) {
            return doReadJSON(in, type, null, dateTimeFormat, lenient, trackOrigins, parsers, nulls, explicitConstructorNames, explicitDataTypes);
        }
        catch (IOException e) {
            throw RuntimeExceptionFactory.io(e);
        }
    }

    public void writeJSON(ISourceLocation loc, IValue value, IBool unpackedLocations, IString dateTimeFormat,
        IBool dateTimeAsInt, IBool rationalsAsString, IInteger indent, IBool dropOrigins, IFunction formatter, IBool explicitConstructorNames,
        IBool explicitDataTypes, IBool fileLocationsAsPathOnly) {
        try (JsonWriter out =
            new JsonWriter(new OutputStreamWriter(URIResolverRegistry.getInstance().getOutputStream(loc, false),
                Charset.forName("UTF8")))) {
            if (indent.intValue() > 0) {
                out.setIndent("        ".substring(0, indent.intValue() % 9));
            }

            new JsonValueWriter()
                .setCalendarFormat(dateTimeFormat.getValue())
                .setDatesAsInt(dateTimeAsInt.getValue())
                .setRationalsAsString(rationalsAsString.getValue())
                .setUnpackedLocations(unpackedLocations.getValue())
                .setDropOrigins(dropOrigins.getValue())
                .setFormatters(formatter)
                .setExplicitConstructorNames(explicitConstructorNames.getValue())
                .setExplicitDataTypes(explicitDataTypes.getValue())
                .setFileLocationsAsPathOnly(fileLocationsAsPathOnly.getValue())
                .write(out, value);
        }
        catch (IOException e) {
            throw RuntimeExceptionFactory.io(e);
        }
    }

    public IString asJSON(IValue value, IBool unpackedLocations, IString dateTimeFormat, IBool dateTimeAsInt, IBool rationalsAsString,
        IInteger indent, IBool dropOrigins, IFunction formatter, IBool explicitConstructorNames,
        IBool explicitDataTypes, IBool fileLocationsAsPathOnly) {
        StringWriter string = new StringWriter();

        try (JsonWriter out = new JsonWriter(string)) {
            if (indent.intValue() > 0) {
                out.setIndent("        ".substring(0, indent.intValue() % 9));
            }
            new JsonValueWriter()
                .setCalendarFormat(dateTimeFormat.getValue())
                .setDatesAsInt(dateTimeAsInt.getValue())
                .setRationalsAsString(rationalsAsString.getValue())
                .setUnpackedLocations(unpackedLocations.getValue())
                .setDropOrigins(dropOrigins.getValue())
                .setFormatters(formatter)
                .setExplicitConstructorNames(explicitConstructorNames.getValue())
                .setExplicitDataTypes(explicitDataTypes.getValue())
                .setFileLocationsAsPathOnly(fileLocationsAsPathOnly.getValue())
                .write(out, value);

            return values.string(string.toString());
        }
        catch (IOException e) {
            throw RuntimeExceptionFactory.io(e);
        }
    }

    private Map<Type, IValue> unreify(IMap nulls) {
        var tr = new TypeReifier(values);
        return nulls.stream().map(t -> (ITuple) t)
            .collect(Collectors.toMap(t -> tr.valueToType((IConstructor) t.get(0)), t -> t.get(1)));
    }    
}