/*
 * Copyright 2019 Scott Logic Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.scottlogic.datahelix.generator.profile.validators.profile.constraints.atomic;


import com.scottlogic.datahelix.generator.common.profile.FieldType;
import com.scottlogic.datahelix.generator.common.validators.ValidationResult;
import com.scottlogic.datahelix.generator.profile.dtos.FieldDTO;
import com.scottlogic.datahelix.generator.profile.dtos.constraints.atomic.textual.RegexConstraintDTO;

import java.util.List;
import java.util.regex.Pattern;

public class RegexConstraintValidator extends AtomicConstraintValidator<RegexConstraintDTO>
{
    public RegexConstraintValidator(List<FieldDTO> fields)
    {
        super(fields);
    }

    @Override
    public final ValidationResult validate(RegexConstraintDTO dto)
    {
        ValidationResult fieldMustBeValid = fieldMustBeValid(dto);
        if(!fieldMustBeValid.isSuccess) return fieldMustBeValid;

        ValidationResult regexMustBeValid = regexMustBeValid(dto);
        if(!regexMustBeValid.isSuccess) return regexMustBeValid;

        return fieldTypeMustMatchValueType(dto, FieldType.STRING);
    }

    private ValidationResult regexMustBeValid(RegexConstraintDTO dto)
    {
        ValidationResult regexMustBeSpecified = regexMustBeSpecified(dto);
        if(!regexMustBeSpecified.isSuccess) return regexMustBeSpecified;
        try
        {
             Pattern.compile(dto.getRegex());
             return ValidationResult.success();
        }
        catch (Exception e)
        {
            return ValidationResult.failure("Regex is invalid | " + e.getMessage());
        }
    }

    private ValidationResult regexMustBeSpecified(RegexConstraintDTO dto)
    {
        String regex = dto.getRegex();
        return regex != null && !regex.isEmpty()
            ? ValidationResult.success()
            : ValidationResult.failure("Text must be specified" + getErrorInfo(dto));
    }
}
