/*
 * Copyright (c) 2014 Cisco Systems, Inc. and others.  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
 */
package org.opendaylight.yangtools.yang.data.codec.gson;

import static com.google.common.base.Verify.verifyNotNull;

import com.google.gson.JsonParseException;
import com.google.gson.stream.JsonReader;
import com.google.gson.stream.JsonToken;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.util.List;
import java.util.function.BiFunction;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.common.QNameModule;
import org.opendaylight.yangtools.yang.common.UnresolvedQName.Unqualified;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizationException;
import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizationResult;
import org.opendaylight.yangtools.yang.data.impl.codec.AbstractIntegerStringCodec;
import org.opendaylight.yangtools.yang.data.impl.codec.BinaryStringCodec;
import org.opendaylight.yangtools.yang.data.impl.codec.BitsStringCodec;
import org.opendaylight.yangtools.yang.data.impl.codec.BooleanStringCodec;
import org.opendaylight.yangtools.yang.data.impl.codec.DecimalStringCodec;
import org.opendaylight.yangtools.yang.data.impl.codec.EnumStringCodec;
import org.opendaylight.yangtools.yang.data.impl.codec.StringStringCodec;
import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
import org.opendaylight.yangtools.yang.data.impl.schema.NormalizationResultHolder;
import org.opendaylight.yangtools.yang.data.spi.node.ImmutableNodes;
import org.opendaylight.yangtools.yang.data.util.codec.AbstractInputStreamNormalizer;
import org.opendaylight.yangtools.yang.data.util.codec.CodecCache;
import org.opendaylight.yangtools.yang.data.util.codec.LazyCodecCache;
import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
import org.opendaylight.yangtools.yang.model.api.EffectiveStatementInference;
import org.opendaylight.yangtools.yang.model.api.type.BinaryTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.BitsTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.BooleanTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.DecimalTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.EmptyTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.EnumTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.IdentityrefTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.InstanceIdentifierTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Int16TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Int32TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Int64TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Int8TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.StringTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Uint16TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Uint32TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Uint64TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.Uint8TypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.UnionTypeDefinition;
import org.opendaylight.yangtools.yang.model.api.type.UnknownTypeDefinition;
import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;

/**
 * Factory for creating JSON equivalents of codecs. Each instance of this object is bound to
 * a particular {@link EffectiveModelContext}, but can be reused by multiple {@link JSONNormalizedNodeStreamWriter}s.
 */
public abstract sealed class JSONCodecFactory extends AbstractInputStreamNormalizer<JSONCodec<?>> {
    @Deprecated(since = "12.0.0", forRemoval = true)
    static final class Lhotka02 extends JSONCodecFactory {
        Lhotka02(final @NonNull EffectiveModelContext context, final @NonNull CodecCache<JSONCodec<?>> cache) {
            super(context, cache, InstanceIdentifierJSONCodec.Lhotka02::new);
        }

        @Override
        Lhotka02 rebaseTo(final EffectiveModelContext newSchemaContext, final CodecCache<JSONCodec<?>> newCache) {
            return new Lhotka02(newSchemaContext, newCache);
        }

        @Override
        JSONCodec<?> wrapDecimalCodec(final DecimalStringCodec decimalCodec) {
            return new NumberJSONCodec<>(decimalCodec);
        }

        @Override
        JSONCodec<?> wrapIntegerCodec(final AbstractIntegerStringCodec<?, ?> integerCodec) {
            return new NumberJSONCodec<>(integerCodec);
        }
    }

    static final class RFC7951 extends JSONCodecFactory {
        RFC7951(final @NonNull  EffectiveModelContext context, final @NonNull CodecCache<JSONCodec<?>> cache) {
            super(context, cache, InstanceIdentifierJSONCodec.RFC7951::new);
        }

        @Override
        RFC7951 rebaseTo(final EffectiveModelContext newSchemaContext, final CodecCache<JSONCodec<?>> newCache) {
            return new RFC7951(newSchemaContext, newCache);
        }

        @Override
        JSONCodec<?> wrapDecimalCodec(final DecimalStringCodec decimalCodec) {
            return new QuotedJSONCodec<>(decimalCodec);
        }

        @Override
        JSONCodec<?> wrapIntegerCodec(final AbstractIntegerStringCodec<?, ?> integerCodec) {
            return new QuotedJSONCodec<>(integerCodec);
        }
    }

    private final @NonNull InstanceIdentifierJSONCodec iidCodec;

    @SuppressFBWarnings(value = "MC_OVERRIDABLE_METHOD_CALL_IN_CONSTRUCTOR",
        justification = "https://github.com/spotbugs/spotbugs/issues/1867")
    private JSONCodecFactory(final @NonNull EffectiveModelContext context,
            final @NonNull CodecCache<JSONCodec<?>> cache,
            final BiFunction<EffectiveModelContext, JSONCodecFactory, @NonNull InstanceIdentifierJSONCodec> iidCodec) {
        super(context, cache);
        this.iidCodec = verifyNotNull(iidCodec.apply(context, this));
    }

    @Override
    protected final JSONCodec<?> binaryCodec(final BinaryTypeDefinition type) {
        return new QuotedJSONCodec<>(BinaryStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> booleanCodec(final BooleanTypeDefinition type) {
        return new BooleanJSONCodec(BooleanStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> bitsCodec(final BitsTypeDefinition type) {
        return new QuotedJSONCodec<>(BitsStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> decimalCodec(final DecimalTypeDefinition type) {
        return wrapDecimalCodec(DecimalStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> emptyCodec(final EmptyTypeDefinition type) {
        return EmptyJSONCodec.INSTANCE;
    }

    @Override
    protected final JSONCodec<?> enumCodec(final EnumTypeDefinition type) {
        return new QuotedJSONCodec<>(EnumStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<QName> identityRefCodec(final IdentityrefTypeDefinition type, final QNameModule module) {
        return new IdentityrefJSONCodec(modelContext(), module);
    }

    @Override
    protected final JSONCodec<YangInstanceIdentifier> instanceIdentifierCodec(
            final InstanceIdentifierTypeDefinition type) {
        return iidCodec;
    }

    @Override
    public JSONCodec<YangInstanceIdentifier> instanceIdentifierCodec() {
        return iidCodec;
    }

    @Override
    protected final JSONCodec<?> int8Codec(final Int8TypeDefinition type) {
        return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> int16Codec(final Int16TypeDefinition type) {
        return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> int32Codec(final Int32TypeDefinition type) {
        return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> int64Codec(final Int64TypeDefinition type) {
        return wrapIntegerCodec(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> stringCodec(final StringTypeDefinition type) {
        return new QuotedJSONCodec<>(StringStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> uint8Codec(final Uint8TypeDefinition type) {
        return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> uint16Codec(final Uint16TypeDefinition type) {
        return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> uint32Codec(final Uint32TypeDefinition type) {
        return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> uint64Codec(final Uint64TypeDefinition type) {
        return wrapIntegerCodec(AbstractIntegerStringCodec.from(type));
    }

    @Override
    protected final JSONCodec<?> unionCodec(final UnionTypeDefinition type, final List<JSONCodec<?>> codecs) {
        return UnionJSONCodec.create(type, codecs);
    }

    @Override
    @Deprecated(since = "13.0.3", forRemoval = true)
    protected final JSONCodec<?> unknownCodec(final UnknownTypeDefinition type) {
        return NullJSONCodec.INSTANCE;
    }

    // Returns a one-off factory for the purposes of normalizing an anydata tree.
    //
    // FIXME: 7.0.0: this is really ugly, as we should be able to tell if the new context is the same as ours and
    //               whether our cache is thread-safe -- in which case we should just return this.
    //               The supplier/cache/factory layout needs to be reworked so that this call ends up being equivalent
    //               to JSONCodecFactorySupplier.getShared() in case this factory is not thread safe.
    //
    //               The above is not currently possible, as we cannot reference JSONCodecFactorySupplier from the
    //               factory due to that potentially creating a circular reference.
    final JSONCodecFactory rebaseTo(final EffectiveModelContext newSchemaContext) {
        return rebaseTo(newSchemaContext, new LazyCodecCache<>());
    }

    abstract JSONCodecFactory rebaseTo(EffectiveModelContext newSchemaContext, CodecCache<JSONCodec<?>> newCache);

    abstract JSONCodec<?> wrapDecimalCodec(DecimalStringCodec decimalCodec);

    abstract JSONCodec<?> wrapIntegerCodec(AbstractIntegerStringCodec<?, ?> integerCodec);

    @Override
    protected final NormalizationResult<ContainerNode> parseDatastore(final InputStream stream,
            final NodeIdentifier containerName, final Unqualified moduleName)
                throws IOException, NormalizationException {
        // This is bit more involved: given this example document:
        //
        //          {
        //            "ietf-restconf:data" : {
        //              "foo:foo" : {
        //                "str" : "str"
        //              }
        //            }
        //          }
        //
        // we need to first peel this part:
        //
        //          {
        //            "ietf-restconf:data" :
        //
        // validating it really the name matches rootName and that it is followed by '{', i.e. it really is an object.
        //
        // We then need to essentially do the equivalent of parseStream() on the EffectiveModelContext, but the receiver
        // should be the builder for our resulting node -- we cannot and do not want to use a holder, as can legally
        // more than one child.
        //
        // Then we need to take care of the last closing brace, raising an error if there is any other content -- i.e.
        // we need to reach the end of JsonReader.
        //
        // And then it's just a matter of returning the built container.
        try (var reader = new JsonReader(new InputStreamReader(stream, StandardCharsets.UTF_8))) {
            reader.beginObject();
            final var name = reader.nextName();
            final var expected = moduleName.getLocalName() + ':' + containerName.getNodeType().getLocalName();
            if (!expected.equals(name)) {
                throw NormalizationException.ofMessage("Expected name '" + expected + "', got '" + name + "'");
            }

            final var builder = ImmutableNodes.newContainerBuilder().withNodeIdentifier(containerName);

            if (reader.peek() == JsonToken.BEGIN_OBJECT) {
                try (var writer = ImmutableNormalizedNodeStreamWriter.from(builder)) {
                    try (var parser = JsonParserStream.create(writer, this)) {
                        parser.parse(reader);
                    } catch (JsonParseException e) {
                        throw NormalizationException.ofCause(e);
                    }
                }
            }

            reader.endObject();
            final var nextToken = reader.peek();
            if (nextToken != JsonToken.END_DOCUMENT) {
                throw NormalizationException.ofMessage("Expected end of JSON document, got " + nextToken);
            }
            return new NormalizationResult<>(builder.build());
        } catch (IllegalStateException e) {
            throw NormalizationException.ofCause(e);
        }
    }

    @Override
    protected final NormalizationResult<?> parseData(final SchemaInferenceStack stack, final InputStream stream)
            throws IOException, NormalizationException {
        // Point to parent node
        stack.exit();
        return parseStream(stack.toInference(), stream);
    }

    @Override
    protected final NormalizationResult<?> parseChildData(final InputStream stream,
            final EffectiveStatementInference inference) throws IOException, NormalizationException {
        return parseStream(inference, stream);
    }

    @Override
    protected final NormalizationResult<?> parseInputOutput(final SchemaInferenceStack stack, final QName expected,
            final InputStream stream) throws IOException, NormalizationException {
        return checkNodeName(parseStream(stack.toInference(), stream), expected);
    }

    private @NonNull NormalizationResult<?> parseStream(final @NonNull EffectiveStatementInference inference,
            final @NonNull InputStream stream) throws IOException, NormalizationException {
        try (var reader = new JsonReader(new InputStreamReader(stream, StandardCharsets.UTF_8))) {
            final var holder = new NormalizationResultHolder();
            try (var writer = ImmutableNormalizedNodeStreamWriter.from(holder)) {
                try (var parser = JsonParserStream.create(writer, this, inference)) {
                    parser.parse(reader);
                } catch (JsonParseException e) {
                    throw NormalizationException.ofCause(e);
                }
            }
            return holder.getResult();
        }
    }
}