package cy.agorise.graphenej;

import com.google.gson.JsonArray;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonParseException;

import java.lang.reflect.Type;

import cy.agorise.graphenej.interfaces.ByteSerializable;
import cy.agorise.graphenej.interfaces.JsonSerializable;
import cy.agorise.graphenej.operations.TransferOperation;

/**
 * Base class that represents a generic operation
 */
public abstract class BaseOperation implements ByteSerializable, JsonSerializable {

    public static final String KEY_FEE = "fee";
    public static final String KEY_EXTENSIONS = "extensions";

    protected OperationType type;
    protected Extensions extensions;

    public BaseOperation(OperationType type){
        this.type = type;
        this.extensions = new Extensions();
    }

    public byte getId() {
        return (byte) this.type.ordinal();
    }

    public abstract void setFee(AssetAmount assetAmount);

    public JsonElement toJsonObject(){
        JsonArray array = new JsonArray();
        array.add(this.getId());
        return array;
    }

    /**
     * <p>
     * De-serializer used to unpack data from a generic operation. The general format used in the
     * JSON-RPC blockchain API is the following:
     * </p>
     *
     * <code>[OPERATION_ID, OPERATION_OBJECT]</code><br>
     *
     * <p>
     * Where <code>OPERATION_ID</code> is one of the operations defined in {@link cy.agorise.graphenej.OperationType}
     * and <code>OPERATION_OBJECT</code> is the actual operation serialized in the JSON format.
     * </p>
     * Here's an example of this serialized form for a transfer operation:<br><br>
     *<pre>
     *[
     *   0,
     *   {
     *       "fee": {
     *           "amount": 264174,
     *           "asset_id": "1.3.0"
     *       },
     *       "from": "1.2.138632",
     *       "to": "1.2.129848",
     *       "amount": {
     *           "amount": 100,
     *           "asset_id": "1.3.0"
     *       },
     *       "extensions": []
     *   }
     *]
     *</pre><br>
     * If this class is used, this serialized data will be translated to a TransferOperation object instance.<br>
     *
     * TODO: Add support for operations other than the 'transfer'
     */
    public static class OperationDeserializer implements JsonDeserializer<BaseOperation> {

        @Override
        public BaseOperation deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
            BaseOperation operation = null;
            if(json.isJsonArray()){
                JsonArray array = json.getAsJsonArray();
                if(array.get(0).getAsLong() == OperationType.TRANSFER_OPERATION.ordinal()){
                    operation = context.deserialize(array.get(1), TransferOperation.class);
                }
            }
            return operation;
        }
    }
}