/**
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/.
 */
package org.mifosplatform.useradministration.service;

import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.commons.lang.StringUtils;
import org.mifosplatform.infrastructure.core.data.ApiParameterError;
import org.mifosplatform.infrastructure.core.data.DataValidatorBuilder;
import org.mifosplatform.infrastructure.core.exception.InvalidJsonException;
import org.mifosplatform.infrastructure.core.exception.PlatformApiDataValidationException;
import org.mifosplatform.infrastructure.core.serialization.FromJsonHelper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import com.google.gson.JsonElement;
import com.google.gson.reflect.TypeToken;

@Component
public final class RoleDataValidator {

    /**
     * The parameters supported for this command.
     */
    private final Set<String> supportedParameters = new HashSet<>(Arrays.asList("id", "name", "description"));

    private final FromJsonHelper fromApiJsonHelper;

    @Autowired
    public RoleDataValidator(final FromJsonHelper fromApiJsonHelper) {
        this.fromApiJsonHelper = fromApiJsonHelper;
    }

    public void validateForCreate(final String json) {
        if (StringUtils.isBlank(json)) { throw new InvalidJsonException(); }

        final Type typeOfMap = new TypeToken<Map<String, Object>>() {}.getType();
        this.fromApiJsonHelper.checkForUnsupportedParameters(typeOfMap, json, this.supportedParameters);

        final List<ApiParameterError> dataValidationErrors = new ArrayList<>();
        final DataValidatorBuilder baseDataValidator = new DataValidatorBuilder(dataValidationErrors).resource("role");

        final JsonElement element = this.fromApiJsonHelper.parse(json);

        final String name = this.fromApiJsonHelper.extractStringNamed("name", element);
        baseDataValidator.reset().parameter("name").value(name).notBlank().notExceedingLengthOf(100);

        final String description = this.fromApiJsonHelper.extractStringNamed("description", element);
        baseDataValidator.reset().parameter("description").value(description).notBlank().notExceedingLengthOf(500);

        throwExceptionIfValidationWarningsExist(dataValidationErrors);
    }

    public void validateForUpdate(final String json) {
        if (StringUtils.isBlank(json)) { throw new InvalidJsonException(); }

        final Type typeOfMap = new TypeToken<Map<String, Object>>() {}.getType();
        this.fromApiJsonHelper.checkForUnsupportedParameters(typeOfMap, json, this.supportedParameters);

        final List<ApiParameterError> dataValidationErrors = new ArrayList<>();
        final DataValidatorBuilder baseDataValidator = new DataValidatorBuilder(dataValidationErrors).resource("role");

        final JsonElement element = this.fromApiJsonHelper.parse(json);

        if (this.fromApiJsonHelper.parameterExists("name", element)) {
            final String username = this.fromApiJsonHelper.extractStringNamed("name", element);
            baseDataValidator.reset().parameter("name").value(username).notBlank().notExceedingLengthOf(100);
        }

        if (this.fromApiJsonHelper.parameterExists("description", element)) {
            final String description = this.fromApiJsonHelper.extractStringNamed("description", element);
            baseDataValidator.reset().parameter("description").value(description).notBlank().notExceedingLengthOf(500);
        }

        throwExceptionIfValidationWarningsExist(dataValidationErrors);
    }

    private void throwExceptionIfValidationWarningsExist(final List<ApiParameterError> dataValidationErrors) {
        if (!dataValidationErrors.isEmpty()) { throw new PlatformApiDataValidationException(dataValidationErrors); }
    }
}