package at.gv.egiz.moazs.preprocess;

import at.gv.zustellung.app2mzs.xsd.ConfigType;
import at.gv.zustellung.app2mzs.xsd.DeliveryRequestType;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.Map;

import static at.gv.egiz.moazs.MoaZSException.moaZSException;
import static at.gv.zustellung.app2mzs.xsd.DeliveryRequestType.deliveryRequestTypeBuilder;
import static java.lang.String.format;

@Component
public class DeliveryRequestAugmenter {

    private final ConfigUtil util;
    private final Map<String, ConfigType> configs;
    private final MzsDeliveryRequestValidator validator;

    private static final String INCOMPLETE_TNVZ_ERROR_MESSAGE = "mzs:DeliveryRequest is incomplete because mandatory " +
            "fields for sending a tnvz:QueryPersonRequest are missing.";
    private static final String INCOMPLETE_CONFIG_ERROR_MESSAGE = "Could not find a profile for " +
            "the delivery request configuration, and the configuration attached to mzs:DeliveryRequest is incomplete.";
    private static final String INCOMPLETE_MERGED_CONFIG_ERROR_MESSAGE = "I merged parameters from " +
            "mzs:DeliveryRequest/Config with parameters from config profile with ProfileId='%s', but the " +
            "configuration is incomplete.";

    @Autowired
    public DeliveryRequestAugmenter(Map<String, ConfigType> deliveryRequestConfigs, ConfigUtil util, MzsDeliveryRequestValidator validator) {
        this.configs = deliveryRequestConfigs;
        this.util = util;
        this.validator = validator;
    }

    /**
     * Augments an incoming {@code request} by filling gaps with config- or default parameters.
     *
     * @param request
     * @throws at.gv.egiz.moazs.MoaZSException
     * @return augmented request and validated
     */
    public DeliveryRequestType augment(DeliveryRequestType request) {

        var requestConfig = request.getConfig();
        var fallbackProfileId = determineProfileIdFrom(requestConfig);
        var fallbackConfig = configs.get(fallbackProfileId);

        if (fallbackConfig == null) {

            if (!validator.isConfigProfileComplete(request.getConfig())) {
                throw moaZSException(INCOMPLETE_CONFIG_ERROR_MESSAGE);
            } else if (!validator.isTnvzComplete(request)) {
                throw moaZSException(INCOMPLETE_TNVZ_ERROR_MESSAGE);
            } else {
                return request;
            }

        } else {

            var mergedConfig = (requestConfig == null)
                    ? fallbackConfig
                    : util.merge(requestConfig, fallbackConfig);

            if (!validator.isConfigProfileComplete(mergedConfig)) {
                var message = format(INCOMPLETE_MERGED_CONFIG_ERROR_MESSAGE, fallbackProfileId);
                throw moaZSException(message);
            }

            var mergedRequest = deliveryRequestTypeBuilder(request)
                    .withConfig(mergedConfig)
                    .build();

            if (!validator.isTnvzComplete(mergedRequest)) {
                throw moaZSException(INCOMPLETE_TNVZ_ERROR_MESSAGE);
            }

            return mergedRequest;

        }
    }

    private String determineProfileIdFrom(ConfigType requestConfig) {
        return (requestConfig == null
                || requestConfig.getProfileID() == null
                || isProfileMissing(requestConfig.getProfileID()))
                ? "default"
                : requestConfig.getProfileID();
    }

    private boolean isProfileMissing(String id) {
        return !configs.containsKey(id);
    }

}