/*
* Copyright 2025 Google. This software is provided as-is, without warranty or representation for any use or purpose.
* Your use of it is subject to your agreement with Google.
*/

package com.example.util;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.google.cloud.Timestamp;
import java.io.IOException;

/**
 * Custom Jackson Serializer for com.google.cloud.Timestamp.
 * This is crucial for ObjectMapper.convertValue to correctly handle Timestamp objects
 * when they are encountered in a Map<String, Object> and need to be internally
 * serialized before deserialization into a DTO. It converts Timestamp into a
 * simple JSON object with "seconds" and "nanos" fields.
 */
public class FirestoreTimestampSerializer extends JsonSerializer<Timestamp> {

    @Override
    public void serialize(Timestamp value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
        if (value == null) {
            gen.writeNull();
        } else {
            // Write Timestamp as a JSON object with seconds and nanos
            gen.writeStartObject();
            gen.writeNumberField("seconds", value.getSeconds());
            gen.writeNumberField("nanos", value.getNanos());
            gen.writeEndObject();
        }
    }
}