ArekX\PQL\Drivers\Pdo\MySql\Builders\CaseWhenBuilder

Complexity

Total Complexity

7

Size/Duplication

Total Lines	73
Duplicated Lines	0 %

Test Coverage

Coverage

100%

Importance

Changes	1
Bugs	0	Features	0

6 Methods

Rating	Name	Duplication	Size	Complexity
A	getLastParts()	0	3	1
A	buildElse()	0	3	1
A	buildWhen()	0	12	2
A	getPartBuilders()	0	5	1
A	getInitialParts()	0	3	1
A	getRequiredParts()	0	3	1

<?php
/**
 * Copyright 2021 Aleksandar Panic
 *
 * 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.
 */

namespace ArekX\PQL\Drivers\Pdo\MySql\Builders;

use ArekX\PQL\Contracts\StructuredQuery;
use ArekX\PQL\Drivers\Pdo\MySql\Builders\Traits\ConditionTrait;
use ArekX\PQL\Drivers\Pdo\MySql\Builders\Traits\ValueColumnTrait;
use ArekX\PQL\Drivers\Pdo\MySql\MySqlQueryBuilderState;
use ArekX\PQL\Sql\Statement\CaseWhen;
use Exception;

/**
 * Represents a query builder for building a CASE statement
 *
 * @see CaseWhen
 */
class CaseWhenBuilder extends QueryPartBuilder
{
    use ConditionTrait;
    use ValueColumnTrait;

    /**
     * @inheritDoc
     */
    protected function getInitialParts(): array
    {
        return ['CASE'];
    }

    /**
     * @inheritDoc
     */
    protected function getLastParts(): array
    {
        return ['END'];
    }

    /**
     * @inheritDoc
     */
    protected function getRequiredParts(): array
    {
        return ['when'];
    }

    /**
     * @inheritDoc
     */
    protected function getPartBuilders(): array
    {
        return [
            'when' => fn($name, MySqlQueryBuilderState $state) => $this->buildWhen($name, $state),
            'else' => fn($name, MySqlQueryBuilderState $state) => $this->buildElse($name, $state),
        ];
    }

    /**
     * Build series of WHEN parts of the CASE.
     *
     * @param array $whenList List of [when, then] values to be built.
     * @param MySqlQueryBuilderState $state
     * @return string
     * @throws Exception
     */
    protected function buildWhen(array $whenList, MySqlQueryBuilderState $state): string
    {
        $result = [];

        foreach ($whenList as $whenItem) {
            [$when, $then] = $whenItem;

            $result[] = 'WHEN ' . $this->buildCondition($when, $state)
                . ' THEN ' . $this->buildValueColumn($then, $state);
        }

        return implode(' ', $result);
    }

    /**
     * Build ELSE part of the case
     *
     * @param array|StructuredQuery $else Value to be built
     * @param MySqlQueryBuilderState $state Current query builder state
     * @return string
     * @throws Exception
     */
    protected function buildElse(StructuredQuery|array $else, MySqlQueryBuilderState $state): string
    {
        return 'ELSE ' . $this->buildValueColumn($else, $state);
    }
}