ConditionalQueryBuilder.php

<?php

/*
 * Opulence
 *
 * @link      https://www.opulencephp.com
 * @copyright Copyright (C) 2021 David Young
 * @license   https://github.com/opulencephp/Opulence/blob/1.2/LICENSE.md
 */

namespace Opulence\QueryBuilders;

/**
 * Builds parts of a query that can use a "WHERE" clause
 */
class ConditionalQueryBuilder
{
    /** @var array The list of WHERE expressions */
    protected $whereConditions = [];

    /**
     * Adds a condition to a clause
     *
     * @param array $clauseConditions The list of conditions that already belong to the clause
     * @param string $operation Either "AND" or "OR", indicating how this condition is being added to the list of conditions
     * @param string ...$conditions A variable list of conditions to be met
     * @return array The input array with the condition added
     */
    public function addConditionToClause(array $clauseConditions, string $operation, string ...$conditions) : array
    {
        foreach ($conditions as $condition) {
            $clauseConditions[] = ['operation' => $operation, 'condition' => $condition];
        }

        return $clauseConditions;
    }

    /**
     * Adds to a "WHERE" condition that will be "AND"ed with other conditions
     *
     * @param string ...$condition A variable list of conditions to be met
     * @return self For method chaining
     */
    public function andWhere(string ...$condition) : self
    {
        $this->whereConditions = $this->addConditionToClause(
            $this->whereConditions, 'AND', ...$condition);

        return $this;
    }

    /**
     * Gets the SQL that makes up a clause that permits boolean operations ie "AND" and "OR"
     *
     * @param string $conditionType The name of the condition type ie "WHERE"
     * @param array $clauseConditions The array of condition data whose SQL we want
     * @return string The SQL that makes up the input clause(s)
     */
    public function getClauseConditionSql(string $conditionType, array $clauseConditions) : string
    {
        if (count($clauseConditions) === 0) {
            return '';
        }

        $sql = ' ' . strtoupper($conditionType);
        // This will help us keep track of whether or not we've added at least one clause
        $haveAddedAClause = false;

        foreach ($clauseConditions as $conditionData) {
            $sql .= ($haveAddedAClause ? ' ' . strtoupper($conditionData['operation']) : '')
                . " ({$conditionData['condition']})";
            $haveAddedAClause = true;
        }

        return $sql;
    }

    /**
     * @return array
     */
    public function getWhereConditions() : array
    {
        return $this->whereConditions;
    }

    /**
     * Adds to a "WHERE" condition that will be "OR"ed with other conditions
     *
     * @param string ...$condition A variable list of conditions to be met
     * @return self For method chaining
     */
    public function orWhere(string ...$condition) : self
    {
        $this->whereConditions = $this->addConditionToClause(
            $this->whereConditions, 'OR', ...$condition);

        return $this;
    }

    /**
     * Starts a "WHERE" condition
     * Only call this method once per query because it will overwrite any previously-set "WHERE" expressions
     *
     * @param string ...$condition A variable list of conditions to be met
     * @return self For method chaining
     */
    public function where(string ...$condition) : self
    {
        // We want to wipe out anything already in the condition list
        $this->whereConditions = [];
        $this->whereConditions = $this->addConditionToClause(
            $this->whereConditions, 'AND', ...$condition);

        return $this;
    }
}