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package com.fitbur.jackson.databind.ser.std;

import java.io.IOException;
import java.util.Calendar;
import java.util.Date;

import com.fitbur.jackson.core.*;
import com.fitbur.jackson.databind.*;
import com.fitbur.jackson.databind.ser.impl.PropertySerializerMap;

@SuppressWarnings("serial")
public class StdKeySerializers
{
    protected final static JsonSerializer DEFAULT_KEY_SERIALIZER = new StdKeySerializer();

    protected final static JsonSerializer DEFAULT_STRING_SERIALIZER = new StringKeySerializer();

    private StdKeySerializers() { }

    /**
     * @param config Serialization configuration in use, may be needed in choosing
     *    serializer to use
     * @param rawKeyType Type of key values to serialize
     * @param useDefault If no match is found, should we return fallback deserializer
     *    (true), or null (false)?
     */
    public static JsonSerializer getStdKeySerializer(SerializationConfig config,
            Class rawKeyType, boolean useDefault)
    {
        // 24-Sep-2015, tatu: Important -- should ONLY consider types for which `@JsonValue`
        //    can not be used, since caller has not yet checked for that annotation
        //    This is why Enum types are not handled here quite yet

        // [databind#943: Use a dynamic key serializer if we are not given actual
        // type declaration
        if ((rawKeyType == null) || (rawKeyType == Object.class)) {
            return new Dynamic();
        }
        if (rawKeyType == String.class) {
            return DEFAULT_STRING_SERIALIZER;
        }
        if (rawKeyType.isPrimitive() || Number.class.isAssignableFrom(rawKeyType)) {
            return DEFAULT_KEY_SERIALIZER;
        }
        if (rawKeyType == Class.class) {
            return new Default(Default.TYPE_CLASS, rawKeyType);
        }
        if (Date.class.isAssignableFrom(rawKeyType)) {
            return new Default(Default.TYPE_DATE, rawKeyType);
        }
        if (Calendar.class.isAssignableFrom(rawKeyType)) {
            return new Default(Default.TYPE_CALENDAR, rawKeyType);
        }
        // other JDK types we know convert properly with 'toString()'?
        if (rawKeyType == java.util.UUID.class) {
            return new Default(Default.TYPE_TO_STRING, rawKeyType);
        }
        return useDefault ? DEFAULT_KEY_SERIALIZER : null;
    }

    /**
     * Method called if no specified key serializer was located; will return a
     * "default" key serializer.
     *
     * @since 2.7
     */
    public static JsonSerializer getFallbackKeySerializer(SerializationConfig config,
            Class rawKeyType) {
        if (rawKeyType != null) {
            // 29-Sep-2015, tatu: Odd case here, of `Enum`, which we may get for `EnumMap`; not sure
            //   if that is a bug or feature. Regardless, it seems to require dynamic handling
            //   (compared to getting actual fully typed Enum).
            //  Note that this might even work from the earlier point, but let's play it safe for now
            if (rawKeyType == Enum.class) {
                return new Dynamic();
            }
            if (rawKeyType.isEnum()) {
                return new Default(Default.TYPE_ENUM, rawKeyType);
            }
        }
        return DEFAULT_KEY_SERIALIZER;
    }

    /**
     * @deprecated since 2.7
     */
    @Deprecated
    public static JsonSerializer getDefault() {
        return DEFAULT_KEY_SERIALIZER;
    }

    /*
    /**********************************************************
    /* Standard implementations used
    /**********************************************************
     */

    /**
     * This is a "chameleon" style multi-type key serializer for simple
     * standard JDK types.
     *

* TODO: Should (but does not yet) support re-configuring format used for * {@link java.util.Date} and {@link java.util.Calendar} key serializers, * as well as alternative configuration of Enum key serializers. */ public static class Default extends StdSerializer { final static int TYPE_DATE = 1; final static int TYPE_CALENDAR = 2; final static int TYPE_CLASS = 3; final static int TYPE_ENUM = 4; final static int TYPE_TO_STRING = 5; protected final int _typeId; public Default(int typeId, Class type) { super(type, false); _typeId = typeId; } @Override public void serialize(Object value, JsonGenerator g, SerializerProvider provider) throws IOException { switch (_typeId) { case TYPE_DATE: provider.defaultSerializeDateKey((Date)value, g); break; case TYPE_CALENDAR: provider.defaultSerializeDateKey(((Calendar) value).getTimeInMillis(), g); break; case TYPE_CLASS: g.writeFieldName(((Class)value).getName()); break; case TYPE_ENUM: { String str = provider.isEnabled(SerializationFeature.WRITE_ENUMS_USING_TO_STRING) ? value.toString() : ((Enum) value).name(); g.writeFieldName(str); } break; case TYPE_TO_STRING: default: g.writeFieldName(value.toString()); } } } /** * Key serializer used when key type is not known statically, and actual key * serializer needs to be dynamically located. */ public static class Dynamic extends StdSerializer { // Important: MUST be transient, to allow serialization of key serializer itself protected transient PropertySerializerMap _dynamicSerializers; public Dynamic() { super(String.class, false); _dynamicSerializers = PropertySerializerMap.emptyForProperties(); } Object readResolve() { // Since it's transient, and since JDK serialization by-passes ctor, need this: _dynamicSerializers = PropertySerializerMap.emptyForProperties(); return this; } @Override public void serialize(Object value, JsonGenerator g, SerializerProvider provider) throws IOException { Class cls = value.getClass(); PropertySerializerMap m = _dynamicSerializers; JsonSerializer ser = m.serializerFor(cls); if (ser == null) { ser = _findAndAddDynamic(m, cls, provider); } ser.serialize(value, g, provider); } protected JsonSerializer _findAndAddDynamic(PropertySerializerMap map, Class type, SerializerProvider provider) throws JsonMappingException { PropertySerializerMap.SerializerAndMapResult result = // null -> for now we won't keep ref or pass BeanProperty; could change map.findAndAddKeySerializer(type, provider, null); // did we get a new map of serializers? If so, start using it if (map != result.map) { _dynamicSerializers = result.map; } return result.serializer; } } /** * Simple and fast key serializer when keys are Strings. */ public static class StringKeySerializer extends StdSerializer { public StringKeySerializer() { super(String.class, false); } @Override public void serialize(Object value, JsonGenerator g, SerializerProvider provider) throws IOException { g.writeFieldName((String) value); } } }