<?php
/**
 * @link https://craftcms.com/
 * @copyright Copyright (c) Pixel & Tonic, Inc.
 * @license https://craftcms.github.io/license/
 */

namespace craft\helpers;

use Craft;
use craft\base\Serializable;
use craft\db\Connection;
use craft\db\mysql\Schema as MysqlSchema;
use craft\db\pgsql\Schema as PgsqlSchema;
use craft\db\Query;
use craft\db\QueryParam;
use DateTimeInterface;
use DateTimeZone;
use Money\Money;
use PDO;
use Throwable;
use yii\base\Exception;
use yii\base\InvalidArgumentException;
use yii\base\NotSupportedException;
use yii\db\BatchQueryResult;
use yii\db\Exception as DbException;
use yii\db\ExpressionInterface;
use yii\db\pgsql\Schema as YiiPgqslSchema;
use yii\db\Query as YiiQuery;
use yii\db\QueryInterface;
use yii\db\Schema;

/**
 * Class Db
 *
 * @author Pixel & Tonic, Inc. <support@pixelandtonic.com>
 * @since 3.0.0
 */
class Db
{
    public const SIMPLE_TYPE_NUMERIC = 'numeric';
    public const SIMPLE_TYPE_TEXTUAL = 'textual';

    /**
     * @var string[]
     */
    private static array $_operators = ['not ', '!=', '<=', '>=', '<', '>', '='];

    /**
     * @var string[] Numeric column types
     */
    private static array $_numericColumnTypes = [
        Schema::TYPE_TINYINT,
        Schema::TYPE_SMALLINT,
        Schema::TYPE_INTEGER,
        Schema::TYPE_BIGINT,
        Schema::TYPE_FLOAT,
        Schema::TYPE_DOUBLE,
        Schema::TYPE_DECIMAL,
    ];

    /**
     * @var string[] Textual column types
     */
    private static array $_textualColumnTypes = [
        Schema::TYPE_CHAR,
        Schema::TYPE_STRING,
        Schema::TYPE_TEXT,

        // MySQL-specific ones:
        MysqlSchema::TYPE_TINYTEXT,
        MysqlSchema::TYPE_MEDIUMTEXT,
        MysqlSchema::TYPE_LONGTEXT,
        MysqlSchema::TYPE_ENUM,
    ];

    /**
     * @var array Types of integer columns and how many bytes they can store
     */
    private static array $_integerSizeRanges = [
        Schema::TYPE_SMALLINT => [-32768, 32767],
        Schema::TYPE_INTEGER => [-2147483648, 2147483647],
        Schema::TYPE_BIGINT => [-9223372036854775808, 9223372036854775807],
    ];

    /**
     * @var array Types of MySQL textual columns and how many bytes they can store
     */
    private static array $_mysqlTextSizes = [
        MysqlSchema::TYPE_TINYTEXT => 255,
        Schema::TYPE_TEXT => 65535,
        MysqlSchema::TYPE_MEDIUMTEXT => 16777215,
        MysqlSchema::TYPE_LONGTEXT => 4294967295,
    ];

    /**
     * Prepares an array or object’s values to be sent to the database.
     *
     * @param mixed $values The values to be prepared
     * @return array The prepared values
     */
    public static function prepareValuesForDb(mixed $values): array
    {
        // Normalize to an array
        $values = ArrayHelper::toArray($values, [], false);

        foreach ($values as $key => $value) {
            $values[$key] = static::prepareValueForDb($value);
        }

        return $values;
    }

    /**
     * Prepares a value to be sent to the database.
     *
     * @param mixed $value The value to be prepared
     * @param string|null $columnType The type of column the value will be stored in
     * @return mixed The prepped value
     */
    public static function prepareValueForDb(mixed $value, ?string $columnType = null): mixed
    {
        // Leave expressions alone
        if ($value instanceof ExpressionInterface) {
            return $value;
        }

        // If the object explicitly defines its savable value, use that
        if ($value instanceof Serializable) {
            return $value->serialize();
        }

        // Only DateTime objects and ISO-8601 strings should automatically be detected as dates
        if ($value instanceof DateTimeInterface || DateTimeHelper::isIso8601($value)) {
            return static::prepareDateForDb($value);
        }

        // If this isn’t a JSON column and the value is an object or array, JSON-encode it
        if (is_object($value) || is_array($value)) {
            if (in_array($columnType, [Schema::TYPE_JSON, YiiPgqslSchema::TYPE_JSONB])) {
                return ArrayHelper::toArray($value);
            }
            return Json::encode($value);
        }

        if ($columnType && static::isNumericColumnType($columnType) && is_bool($value)) {
            return (int)$value;
        }

        return $value;
    }

    /**
     * Prepares a date to be sent to the database.
     *
     * @param mixed $date The date to be prepared
     * @return string|null The prepped date, or `null` if it could not be prepared
     */
    public static function prepareDateForDb(mixed $date): ?string
    {
        $date = DateTimeHelper::toDateTime($date);

        if ($date === false) {
            return null;
        }

        $date = clone $date;
        $date->setTimezone(new DateTimeZone('UTC'));
        return $date->format('Y-m-d H:i:s');
    }

    /**
     * Prepares a money object to be sent to the database.
     *
     * @param mixed $money The money to be prepared
     * @return string|null The prepped date, or `null` if it could not be prepared
     * @since 4.0.0
     */
    public static function prepareMoneyForDb(mixed $money): ?string
    {
        $money = MoneyHelper::toMoney($money);

        if ($money === false) {
            return null;
        }

        return $money->getAmount();
    }

    /**
     * Prepares a value to be stored in a JSON column
     *
     * @param array $value The value to be stored as JSON
     * @param Connection|null $db The database connection
     * @return array|string
     * @since 5.0.0
     * @deprecated in 5.2.3
     */
    public static function prepareForJsonColumn(array $value, ?Connection $db = null): array|string
    {
        return $value;
    }

    /**
     * Returns the minimum number allowed for a given column type.
     *
     * @param string $columnType
     * @return int|false The min allowed number, or false if it can't be determined
     */
    public static function getMinAllowedValueForNumericColumn(string $columnType): int|false
    {
        $shortColumnType = self::parseColumnType($columnType);

        if (isset(self::$_integerSizeRanges[$shortColumnType])) {
            return self::$_integerSizeRanges[$shortColumnType][0];
        }

        // ¯\_(ツ)_/¯
        return false;
    }

    /**
     * Returns the maximum number allowed for a given column type.
     *
     * @param string $columnType
     * @return int|false The max allowed number, or false if it can't be determined
     */
    public static function getMaxAllowedValueForNumericColumn(string $columnType): int|false
    {
        $shortColumnType = self::parseColumnType($columnType);

        if (isset(self::$_integerSizeRanges[$shortColumnType])) {
            return self::$_integerSizeRanges[$shortColumnType][1];
        }

        // ¯\_(ツ)_/¯
        return false;
    }

    /**
     * Returns a number column type, taking the min, max, and number of decimal points into account.
     *
     * @param int|null $min
     * @param int|null $max
     * @param int|null $decimals
     * @return string
     * @throws Exception if no column types can contain this
     */
    public static function getNumericalColumnType(?int $min = null, ?int $max = null, ?int $decimals = null): string
    {
        // Normalize the arguments
        if (!is_numeric($min)) {
            $min = self::$_integerSizeRanges[Schema::TYPE_INTEGER][0];
        }

        if (!is_numeric($max)) {
            $max = self::$_integerSizeRanges[Schema::TYPE_INTEGER][1];
        }

        $decimals = is_numeric($decimals) && $decimals > 0 ? (int)$decimals : 0;

        // Figure out the max length
        $maxAbsSize = (int)max(abs($min), abs($max));
        $length = ($maxAbsSize ? mb_strlen((string)$maxAbsSize) : 0) + $decimals;

        // Decimal or int?
        if ($decimals > 0) {
            return Schema::TYPE_DECIMAL . "($length,$decimals)";
        }

        // Figure out the smallest possible int column type that will fit our min/max
        foreach (self::$_integerSizeRanges as $type => [$typeMin, $typeMax]) {
            if ($min >= $typeMin && $max <= $typeMax) {
                return $type . "($length)";
            }
        }

        throw new Exception("No integer column type can contain numbers between $min and $max");
    }

    /**
     * Returns the maximum number of bytes a given textual column type can hold for a given database.
     *
     * @param string $columnType The textual column type to check
     * @param Connection|null $db The database connection
     * @return int|null|false The storage capacity of the column type in bytes, null if unlimited, or false if it can't be determined.
     */
    public static function getTextualColumnStorageCapacity(string $columnType, ?Connection $db = null): int|null|false
    {
        if ($db === null) {
            $db = self::db();
        }

        $shortColumnType = self::parseColumnType($columnType);

        // CHAR and STRING depend on the defined length
        if ($shortColumnType === Schema::TYPE_CHAR || $shortColumnType === Schema::TYPE_STRING) {
            // Convert to the physical column type for the DB driver, to get the default length mixed in
            $physicalColumnType = $db->getQueryBuilder()->getColumnType($columnType);
            if (($length = self::parseColumnLength($physicalColumnType)) !== null) {
                return $length;
            }

            // ¯\_(ツ)_/¯
            return false;
        }

        if ($db->getIsMysql()) {
            return match ($shortColumnType) {
                MysqlSchema::TYPE_ENUM => null, // ENUM depends on the options
                'blob' => self::$_mysqlTextSizes[Schema::TYPE_TEXT],
                'longblob' => self::$_mysqlTextSizes[MysqlSchema::TYPE_LONGTEXT],
                default => self::$_mysqlTextSizes[$shortColumnType] ?? false,
            };
        }

        // Postgres doesn't impose a limit for text/binary fields
        if (in_array($shortColumnType, [Schema::TYPE_TEXT, Schema::TYPE_BINARY])) {
            return null;
        }

        // ¯\_(ツ)_/¯
        return false;
    }

    /**
     * Given a length of a piece of content, returns the underlying database column type to use for saving.
     *
     * @param int $contentLength
     * @param Connection|null $db The database connection
     * @return string
     * @throws Exception if using an unsupported connection type
     */
    public static function getTextualColumnTypeByContentLength(int $contentLength, ?Connection $db = null): string
    {
        if ($db === null) {
            $db = self::db();
        }

        if ($db->getIsMysql()) {
            // MySQL supports a bunch of non-standard text types
            if ($contentLength <= self::$_mysqlTextSizes[MysqlSchema::TYPE_TINYTEXT]) {
                return Schema::TYPE_STRING;
            }

            if ($contentLength <= self::$_mysqlTextSizes[Schema::TYPE_TEXT]) {
                return Schema::TYPE_TEXT;
            }

            if ($contentLength <= self::$_mysqlTextSizes[MysqlSchema::TYPE_MEDIUMTEXT]) {
                return MysqlSchema::TYPE_MEDIUMTEXT;
            }

            return MysqlSchema::TYPE_LONGTEXT;
        }

        return Schema::TYPE_TEXT;
    }

    /**
     * Parses a column type definition and returns just the column type, if it can be determined.
     *
     * @param string $columnType
     * @return string|null
     */
    public static function parseColumnType(string $columnType): ?string
    {
        if (!preg_match('/^\w+/', $columnType, $matches)) {
            return null;
        }

        return strtolower($matches[0]);
    }

    /**
     * Parses a column type definition and returns just the column length/size.
     *
     * @param string $columnType
     * @return int|null
     */
    public static function parseColumnLength(string $columnType): ?int
    {
        if (!preg_match('/^\w+\((\d+)\)/', $columnType, $matches)) {
            return null;
        }

        return (int)$matches[1];
    }

    /**
     * Parses a decimal column type definition and returns just the column precision and scale.
     *
     * @param string $columnType
     * @return array{0:int,1:int}|null
     * @since 5.2.2
     */
    public static function parseColumnPrecisionAndScale(string $columnType): ?array
    {
        if (!preg_match('/^\w+\((\d+),\s*(\d+)\)/', $columnType, $matches)) {
            return null;
        }

        return [(int)$matches[1], (int)$matches[2]];
    }

    /**
     * Returns a simplified version of a given column type.
     *
     * @param string $columnType
     * @return string
     */
    public static function getSimplifiedColumnType(string $columnType): string
    {
        if (($shortColumnType = self::parseColumnType($columnType)) === null) {
            return $columnType;
        }

        // Numeric?
        if (in_array($shortColumnType, self::$_numericColumnTypes, true)) {
            return self::SIMPLE_TYPE_NUMERIC;
        }

        // Textual?
        if (in_array($shortColumnType, self::$_textualColumnTypes, true)) {
            return self::SIMPLE_TYPE_TEXTUAL;
        }

        return $shortColumnType;
    }

    /**
     * Returns whether two column type definitions are relatively compatible with each other.
     *
     * @param string $typeA
     * @param string $typeB
     * @return bool
     */
    public static function areColumnTypesCompatible(string $typeA, string $typeB): bool
    {
        return static::getSimplifiedColumnType($typeA) === static::getSimplifiedColumnType($typeB);
    }

    /**
     * Returns whether the given column type is numeric.
     *
     * @param string $columnType
     * @return bool
     */
    public static function isNumericColumnType(string $columnType): bool
    {
        return in_array(self::parseColumnType($columnType), self::$_numericColumnTypes, true);
    }

    /**
     * Returns whether the given column type is textual.
     *
     * @param string $columnType
     * @return bool
     */
    public static function isTextualColumnType(string $columnType): bool
    {
        return in_array(self::parseColumnType($columnType), self::$_textualColumnTypes, true);
    }

    /**
     * Escapes commas, asterisks, and colons in a string, so they are not treated as special characters in
     * [[parseParam()]].
     *
     * @param string $value The param value.
     * @return string The escaped param value.
     */
    public static function escapeParam(string $value): string
    {
        if (in_array(strtolower($value), [':empty:', 'not :empty:', ':notempty:'])) {
            return "\\$value";
        }

        $value = preg_replace('/(?<!\\\)[,*]/', '\\\$0', $value);

        // If the value starts with an operator, escape that too.
        foreach (self::$_operators as $operator) {
            if (stripos($value, $operator) === 0) {
                $value = "\\$value";
                break;
            }
        }

        return $value;
    }

    /**
     * Unescapes commas, asterisks, and colons added to a string via [[escapeParam()]].
     *
     * @param string $value The param value.
     * @return string The escaped param value.
     * @since 4.4.0
     */
    public static function unescapeParam(string $value): string
    {
        $value = preg_replace('/\\\([,*:])/', '$1', $value);

        // If the value starts with an escaped operator, unescape that too.
        foreach (self::$_operators as $operator) {
            if (stripos($value, "\\$operator") === 0) {
                $value = ltrim($value, '\\');
                break;
            }
        }

        return $value;
    }

    /**
     * Escapes commas in a string so the value doesn’t get interpreted as an array by [[parseParam()]].
     *
     * @param string $value The param value.
     * @return string The escaped param value.
     * @since 4.0.0
     */
    public static function escapeCommas(string $value): string
    {
        return preg_replace('/(?<!\\\),/', '\\\$0', $value);
    }

    /**
     * Escapes underscores within a value for a `LIKE` condition.
     *
     * @param string $value The value
     * @return string The escaped value
     * @since 4.3.7
     */
    public static function escapeForLike(string $value): string
    {
        return preg_replace('/(?<!\\\)_/', '\\_', $value);
    }

    /**
     * Parses a query param value and returns a [[\yii\db\QueryInterface::where()]]-compatible condition.
     *
     * If the `$value` is a string, it will automatically be converted to an array, split on any commas within the
     * string (via [[ArrayHelper::toArray()]]). If that is not desired behavior, you can escape the comma
     * with a backslash before it.
     *
     * The first value can be set to either `and`, `or`, or `not` to define whether *all*, *any*, or *none* of the values must match.
     * (`or` will be assumed by default.)
     *
     * Values can begin with the operators `'not '`, `'!='`, `'<='`, `'>='`, `'<'`, `'>'`, or `'='`. If they don’t,
     * `'='` will be assumed.
     *
     * Values can also be set to either `':empty:'` or `':notempty:'` if you want to search for empty or non-empty
     * database values. (An “empty” value is either `NULL` or an empty string of text).
     *
     * @param string $column The database column that the param is targeting.
     * @param string|int|array $value The param value(s).
     * @param string $defaultOperator The default operator to apply to the values
     * (can be `not`, `!=`, `<=`, `>=`, `<`, `>`, or `=`)
     * @param bool $caseInsensitive Whether the resulting condition should be case-insensitive
     * @param string|null $columnType The database column type the param is targeting
     * @return array|null
     * @throws InvalidArgumentException if the param value isn’t compatible with the column type.
     */
    public static function parseParam(
        string $column,
        mixed $value,
        string $defaultOperator = '=',
        bool $caseInsensitive = false,
        string|null $columnType = null,
    ): ?array {
        $param = QueryParam::parse($value);

        if (empty($param->values)) {
            return null;
        }

        $parsedColumnType = $columnType ? static::parseColumnType($columnType) : null;

        if ($param->operator === QueryParam::NOT) {
            $param->operator = QueryParam::AND;
            $negate = true;
        } else {
            $negate = false;
        }

        $condition = [$param->operator];
        $isMysql = self::db()->getIsMysql();

        // Only PostgreSQL supports case-sensitive strings on non-JSON column values
        if ($isMysql && $columnType !== Schema::TYPE_JSON) {
            $caseInsensitive = false;
        }

        if ($caseInsensitive) {
            $caseColumn = str_contains($column, '(') ? "lower($column)" : "lower([[$column]])";
        } else {
            $caseColumn = $column;
        }

        $inVals = [];
        $notInVals = [];

        foreach ($param->values as $val) {
            self::_normalizeEmptyValue($val);
            $operator = self::_parseParamOperator($val, $defaultOperator, $negate);

            if ($columnType !== null) {
                if ($parsedColumnType === Schema::TYPE_BOOLEAN) {
                    // Convert val to a boolean
                    $val = ($val && $val !== ':empty:');
                    if ($operator === '!=') {
                        $val = !$val;
                    }
                    $condition[] = [$column => $val];
                    continue;
                }

                if (
                    static::isNumericColumnType($columnType) &&
                    $val !== ':empty:' &&
                    !is_numeric($val)
                ) {
                    throw new InvalidArgumentException("Invalid numeric value: $val");
                }
            }

            if ($val === ':empty:') {
                // If this is a textual column type, also check for empty strings
                if (
                    ($columnType === null && $isMysql) ||
                    (
                        $columnType !== null &&
                        ($columnType === Schema::TYPE_JSON || static::isTextualColumnType($columnType))
                    )
                ) {
                    $valCondition = [
                        'or',
                        [$column => null],
                        [$column => ''],
                    ];
                } else {
                    $valCondition = [$column => null];
                }
                if ($operator === '!=') {
                    $valCondition = ['not', $valCondition];
                }
                $condition[] = $valCondition;
                continue;
            }

            if (is_string($val)) {
                // Trim any whitespace from the value
                $val = trim($val);

                // This could be a LIKE condition
                if ($operator === '=' || $operator === '!=') {
                    $val = preg_replace('/^\*|(?<!\\\)\*$/', '%', $val, -1, $count);
                    $like = (bool)$count;
                } else {
                    $like = false;
                }

                // Unescape any asterisks and :empty:/:notempty:
                if (in_array(strtolower($val), ['\\:empty:', '\\:notempty:', '\\not :empty:'])) {
                    $val = ltrim($val, '\\');
                } else {
                    $val = str_replace('\*', '*', $val);
                }

                // if we're prepping to compare to a timestamp - ensure the value is a number not a string
                if ($parsedColumnType === Schema::TYPE_TIMESTAMP) {
                    $val = (int)$val;
                }

                if ($like) {
                    if ($caseInsensitive && !$isMysql) {
                        $operator = $operator === '=' ? 'ilike' : 'not ilike';
                    } else {
                        $operator = $operator === '=' ? 'like' : 'not like';
                    }

                    if ($caseInsensitive && $isMysql) {
                        $condition[] = [$operator, $caseColumn, static::escapeForLike($val), false];
                    } else {
                        $condition[] = [$operator, $column, static::escapeForLike($val), false];
                    }
                    continue;
                }

                if ($caseInsensitive) {
                    $val = mb_strtolower($val);
                }
            }

            // ['or', 1, 2, 3] => IN (1, 2, 3)
            if ($param->operator == QueryParam::OR && $operator === '=') {
                $inVals[] = $val;
                continue;
            }

            // ['and', '!=1', '!=2', '!=3'] => NOT IN (1, 2, 3)
            if ($param->operator == QueryParam::AND && $operator === '!=') {
                $notInVals[] = $val;
                continue;
            }

            $condition[] = [$operator, $caseColumn, $val];
        }

        if (!empty($inVals)) {
            $condition[] = self::_inCondition($caseColumn, $inVals);
        }

        if (!empty($notInVals)) {
            $c = ['not', self::_inCondition($caseColumn, $notInVals)];

            if ($columnType === Schema::TYPE_JSON) {
                $c = [
                    'or',
                    [$column => null],
                    $c,
                ];
            }

            $condition[] = $c;
        }

        // Skip the glue if there's only one condition
        if (count($condition) === 2) {
            return $condition[1];
        }

        return $condition;
    }

    /**
     * Parses a query param value for a date/time column, and returns a
     * [[\yii\db\QueryInterface::where()]]-compatible condition.
     *
     * @param string $column The database column that the param is targeting.
     * @param string|array|DateTimeInterface $value The param value
     * @param string $defaultOperator The default operator to apply to the values
     * (can be `not`, `!=`, `<=`, `>=`, `<`, `>`, or `=`)
     * @return array|null
     */
    public static function parseDateParam(string $column, mixed $value, string $defaultOperator = '='): ?array
    {
        $param = QueryParam::parse($value);

        if (empty($param->values)) {
            return null;
        }

        $normalizedValues = [$param->operator];

        foreach ($param->values as $val) {
            // Is this an empty value?
            self::_normalizeEmptyValue($val);

            if ($val === ':empty:' || $val === 'not :empty:') {
                $normalizedValues[] = $val;

                // Sneak out early
                continue;
            }

            $operator = self::_parseParamOperator($val, $defaultOperator);

            // Assume that date params are set in the system timezone
            $val = DateTimeHelper::toDateTime($val, true);

            $normalizedValues[] = $operator . static::prepareDateForDb($val);
        }

        return static::parseParam($column, $normalizedValues, $defaultOperator, false, Schema::TYPE_DATETIME);
    }

    /**
     * Parses a query param value for a money column, and returns a
     * [[\yii\db\QueryInterface::where()]]-compatible condition.
     *
     * @param string $column The database column that the param is targeting.
     * @param string $currency The currency code to use for the money object.
     * @param string|array|Money $value The param value
     * @param string $defaultOperator The default operator to apply to the values
     * (can be `not`, `!=`, `<=`, `>=`, `<`, `>`, or `=`)
     * @return array|null
     * @since 4.0.0
     */
    public static function parseMoneyParam(
        string $column,
        string $currency,
        mixed $value,
        string $defaultOperator = '=',
    ): ?array {
        $param = QueryParam::parse($value);

        if (empty($param->values)) {
            return null;
        }

        $normalizedValues = [$param->operator];

        foreach ($param->values as $val) {
            // Is this an empty value?
            self::_normalizeEmptyValue($val);

            if ($val === ':empty:' || $val === 'not :empty:') {
                $normalizedValues[] = $val;

                // Sneak out early
                continue;
            }

            $operator = self::_parseParamOperator($val, $defaultOperator);

            // Assume that date params are set in the system timezone
            $val = MoneyHelper::toMoney(['value' => $val, 'currency' => $currency]);

            $normalizedValues[] = $operator . static::prepareMoneyForDb($val);
        }

        return static::parseParam($column, $normalizedValues, $defaultOperator, false, Schema::TYPE_DATETIME);
    }

    /**
     * Parses a query param value for a boolean column and returns a
     * [[\yii\db\QueryInterface::where()]]-compatible condition.
     *
     * The follow values are supported:
     *
     * - `true` or `false`
     * - `:empty:` or `:notempty:` (normalizes to `false` and `true`)
     * - `'not x'` or `'!= x'` (normalizes to the opposite of the boolean value of `x`)
     * - Anything else (normalizes to the boolean value of itself)
     *
     * If `$defaultValue` is set, and it matches the normalized `$value`, then the resulting condition will match any
     * `null` values as well.
     *
     * @param string $column The database column that the param is targeting.
     * @param string|bool|null|array<string|bool|null> $value The param value
     * @param bool|null $defaultValue How `null` values should be treated
     * @param string $columnType The database column type the param is targeting
     * @return array
     * @since 3.4.14
     */
    public static function parseBooleanParam(
        string $column,
        mixed $value,
        ?bool $defaultValue = null,
        string $columnType = Schema::TYPE_BOOLEAN,
    ): array {
        if (is_array($value)) {
            return [
                'or',
                ...array_map(fn($val) => static::parseBooleanParam($column, $val, $defaultValue, $columnType), $value),
            ];
        }

        if ($value !== null) {
            self::_normalizeEmptyValue($value);
            $operator = self::_parseParamOperator($value, '=');
            $value = $value && $value !== ':empty:';
        } else {
            $operator = self::_parseParamOperator($value, '=');
        }

        if ($operator === '!=' && is_bool($value)) {
            $value = !$value;
        }

        if ($columnType === Schema::TYPE_JSON) {
            /** @phpstan-ignore-next-line */
            $value = match ($value) {
                true => 'true',
                false => 'false',
                null => null,
            };
            $defaultValue = match ($defaultValue) {
                true => 'true',
                false => 'false',
                null => null,
            };
        }

        $condition = [$column => $value];
        if ($defaultValue === $value && $value !== null) {
            $condition = ['or', $condition, [$column => null]];
        }

        return $condition;
    }

    /**
     * Parses a query param value for a numeric column and returns a
     * [[\yii\db\QueryInterface::where()]]-compatible condition.
     *
     * The follow values are supported:
     *
     * - A number
     * - `:empty:` or `:notempty:`
     * - `'not x'` or `'!= x'`
     * - `'> x'`, `'>= x'`, `'< x'`, or `'<= x'`, or a combination of those
     *
     * @param string $column The database column that the param is targeting.
     * @param string|string[] $value The param value
     * @param string $defaultOperator The default operator to apply to the values
     * (can be `not`, `!=`, `<=`, `>=`, `<`, `>`, or `=`)
     * @param string|null $columnType The database column type the param is targeting
     * @return array|null
     * @throws InvalidArgumentException if the param value isn’t numeric
     * @since 4.0.0
     */
    public static function parseNumericParam(
        string $column,
        mixed $value,
        string $defaultOperator = '=',
        string|null $columnType = Schema::TYPE_INTEGER,
    ): ?array {
        return static::parseParam($column, $value, $defaultOperator, false, $columnType);
    }

    /**
     * Parses a query param value for a timestamp column and returns a
     * [[\yii\db\QueryInterface::where()]]-compatible condition.
     *
     * The follow values are supported:
     *
     * - A number
     * - `:empty:` or `:notempty:`
     * - `'not x'` or `'!= x'`
     * - `'> x'`, `'>= x'`, `'< x'`, or `'<= x'`, or a combination of those
     *
     * @param string $column The database column that the param is targeting.
     * @param string|string[] $value The param value
     * @param string $defaultOperator The default operator to apply to the values
     * (can be `not`, `!=`, `<=`, `>=`, `<`, `>`, or `=`)
     * @return array|null
     * @throws InvalidArgumentException if the param value isn’t numeric
     * @since 5.1.0
     */
    public static function parseTimestampParam(
        string $column,
        mixed $value,
        string $defaultOperator = '=',
    ): ?array {
        return static::parseParam($column, $value, $defaultOperator, false, Schema::TYPE_TIMESTAMP);
    }

    /**
     * Normalizes a param value with a provided resolver function, unless the resolver function ever returns
     * an empty value.
     *
     * If the original param value began with `and`, `or`, or `not`, that will be preserved.
     *
     * @param mixed $value The param value to be normalized
     * @param callable $resolver Method to resolve non-model values to models
     * @return bool Whether the value was normalized
     * @since 3.7.40
     */
    public static function normalizeParam(&$value, callable $resolver): bool
    {
        if ($value === null) {
            return true;
        }

        if (!is_array($value)) {
            $testValue = [$value];
            if (static::normalizeParam($testValue, $resolver)) {
                $value = $testValue;
                return true;
            }
            return false;
        }

        $normalized = [];

        foreach ($value as $item) {
            if (
                empty($normalized) &&
                is_string($item) &&
                in_array(strtolower($item), [QueryParam::OR, QueryParam::AND, QueryParam::NOT], true)
            ) {
                $normalized[] = strtolower($item);
                continue;
            }

            $item = $resolver($item);
            if (!$item) {
                // The value couldn't be normalized in full, so bail
                return false;
            }

            $normalized[] = $item;
        }

        $value = $normalized;
        return true;
    }

    /**
     * Returns whether a given DB connection’s schema supports a column type.
     *
     * @param string $type
     * @param Connection|null $db
     * @return bool
     * @throws NotSupportedException
     */
    public static function isTypeSupported(string $type, ?Connection $db = null): bool
    {
        if ($db === null) {
            $db = self::db();
        }

        /** @var MysqlSchema|PgsqlSchema $schema */
        $schema = $db->getSchema();

        return isset($schema->typeMap[$type]);
    }

    /**
     * Creates and executes an `INSERT` SQL statement.
     *
     * The method will properly escape the column names, and bind the values to be inserted.
     *
     * If the table contains `dateCreated`, `dateUpdated`, and/or `uid` columns, those values will be included
     * automatically, if not already set.
     *
     * @param string $table The table that new rows will be inserted into
     * @param array $columns The column data (name=>value) to be inserted into the table
     * @param Connection|null $db The database connection to use
     * @return int The number of rows affected by the execution
     * @throws DbException if execution failed
     * @since 3.5.0
     */
    public static function insert(string $table, array $columns, Connection|null $db = null): int
    {
        if ($db === null) {
            $db = self::db();
        }

        return $db->createCommand()
            ->insert($table, $columns)
            ->execute();
    }

    /**
     * Creates and executes a batch `INSERT` SQL statement.
     *
     * The method will properly escape the column names, and bind the values to be inserted.
     *
     * If the table contains `dateCreated`, `dateUpdated`, and/or `uid` columns, those values will be included
     * automatically, if not already set.
     *
     * @param string $table The table that new rows will be inserted into
     * @param array $columns The column names
     * @param array $rows The rows to be batch inserted into the table
     * @param Connection|null $db The database connection to use
     * @return int The number of rows affected by the execution
     * @throws DbException if execution failed
     * @since 3.5.0
     */
    public static function batchInsert(string $table, array $columns, array $rows, Connection|null $db = null): int
    {
        if ($db === null) {
            $db = self::db();
        }

        return $db->createCommand()
            ->batchInsert($table, $columns, $rows)
            ->execute();
    }

    /**
     * Creates and executes a command to insert rows into a database table if
     * they do not already exist (matching unique constraints),
     * or update them if they do.
     *
     * The method will properly escape the column names, and bind the values to be inserted.
     *
     * If the table contains `dateCreated`, `dateUpdated`, and/or `uid` columns, those values will be included
     * for new rows automatically, if not already set.
     *
     * @param string $table the table that new rows will be inserted into/updated in
     * @param array|YiiQuery $insertColumns the column data (name => value) to be inserted into the table or instance
     * of [[Query]] to perform `INSERT INTO ... SELECT` SQL statement
     * @param array|bool $updateColumns the column data (name => value) to be updated if they already exist
     *
     * - If `true` is passed, the column data will be updated to match the insert column data.
     * - If `false` is passed, no update will be performed if the column data already exists.
     *
     * @param array $params the parameters to be bound to the command
     * @param bool $updateTimestamp Whether the `dateUpdated` column should be updated for existing rows, if the table has one.
     * @param Connection|null $db The database connection to use
     * @return int The number of rows affected by the execution
     * @throws DbException if execution failed
     * @since 3.5.0
     */
    public static function upsert(
        string $table,
        array|YiiQuery $insertColumns,
        array|bool $updateColumns = true,
        array $params = [],
        bool $updateTimestamp = true,
        Connection|null $db = null,
    ): int {
        if ($db === null) {
            $db = self::db();
        }

        return $db->createCommand()
            ->upsert($table, $insertColumns, $updateColumns, $params, $updateTimestamp)
            ->execute();
    }

    /**
     * Creates and executes an `UPDATE` SQL statement.
     *
     * The method will properly escape the column names and bind the values to be updated.
     *
     * @param string $table The table to be updated
     * @param array $columns The column data (name => value) to be updated
     * @param string|array $condition The condition that will be put in the `WHERE` part. Please
     * refer to [[Query::where()]] on how to specify condition
     * @param array $params The parameters to be bound to the command
     * @param bool $updateTimestamp Whether the `dateUpdated` column should be updated, if the table has one.
     * @param Connection|null $db The database connection to use
     * @return int The number of rows affected by the execution
     * @throws DbException if execution failed
     * @since 3.5.0
     */
    public static function update(
        string $table,
        array $columns,
        string|array $condition = '',
        array $params = [],
        bool $updateTimestamp = true,
        Connection|null $db = null,
    ): int {
        if ($db === null) {
            $db = self::db();
        }

        return $db->createCommand()
            ->update($table, $columns, $condition, $params, $updateTimestamp)
            ->execute();
    }

    /**
     * Creates and executes an SQL statement for replacing some text with other text in a given table column.
     *
     * @param string $table The table to be updated
     * @param string $column The column to be searched
     * @param string $find The text to be searched for
     * @param string $replace The replacement text
     * @param string|array $condition The condition that will be put in the `WHERE` part. Please
     * refer to [[Query::where()]] on how to specify condition.
     * @param array $params The parameters to be bound to the command
     * @param Connection|null $db The database connection to use
     * @return int The number of rows affected by the execution
     * @throws DbException if execution failed
     * @since 3.5.0
     */
    public static function replace(
        string $table,
        string $column,
        string $find,
        string $replace,
        string|array $condition = '',
        array $params = [],
        Connection|null $db = null,
    ): int {
        if ($db === null) {
            $db = self::db();
        }

        return $db->createCommand()
            ->replace($table, $column, $find, $replace, $condition, $params)
            ->execute();
    }

    /**
     * Creates and executes a `DELETE` SQL statement.
     *
     * @param string $table the table where the data will be deleted from
     * @param string|array $condition the conditions that will be put in the `WHERE` part. Please
     * refer to [[Query::where()]] on how to specify conditions.
     * @param array $params the parameters to be bound to the query.
     * @param Connection|null $db The database connection to use
     * @return int The number of rows affected by the execution
     * @throws DbException if execution failed
     * @since 3.5.0
     */
    public static function delete(
        string $table,
        string|array $condition = '',
        array $params = [],
        Connection|null $db = null,
    ): int {
        if ($db === null) {
            $db = self::db();
        }

        return $db->createCommand()
            ->delete($table, $condition, $params)
            ->execute();
    }

    /**
     * Creates and executes a `DELETE` SQL statement, but only if there are any rows to delete, avoiding deadlock issues
     * when deleting data from large tables.
     *
     * @param string $table the table where the data will be deleted from
     * @param string|array $condition the condition that will be put in the `WHERE` part. Please
     * refer to [[Query::where()]] on how to specify condition.
     * @param array $params the parameters to be bound to the command
     * @param Connection|null $db The database connection to use
     * @return int number of rows affected by the execution
     * @throws DbException execution failed
     * @since 3.0.12
     */
    public static function deleteIfExists(
        string $table,
        string|array $condition = '',
        array $params = [],
        Connection|null $db = null,
    ): int {
        if ($db === null) {
            $db = self::db();
        }

        $exists = (new Query())
            ->from($table)
            ->where($condition, $params)
            ->exists($db);

        return $exists ? static::delete($table, $condition, $params, $db) : 0;
    }

    /**
     * Creates and executes a `TRUNCATE TABLE` SQL statement.
     *
     * @param string $table the table where the data will be deleted from
     * @param Connection|null $db The database connection to use
     * @throws DbException if execution failed
     * @since 3.6.8
     */
    public static function truncateTable(string $table, ?Connection $db = null): void
    {
        if ($db === null) {
            $db = self::db();
        }

        $db->createCommand()
            ->truncateTable($table)
            ->execute();
    }

    /**
     * Creates and executes a SQL statement for dropping an index if it exists.
     *
     * @param string $table The table that the index was created for.
     * @param string|string[] $columns The column(s) that are included in the index. If there are multiple columns, separate them
     * by commas or use an array.
     * @param bool $unique Whether the index has a UNIQUE constraint.
     * @param Connection|null $db The database connection.
     * @since 4.0.0
     */
    public static function dropIndexIfExists(
        string $table,
        string|array $columns,
        bool $unique = false,
        Connection|null $db = null,
    ): void {
        if ($db === null) {
            $db = self::db();
        }

        $indexName = static::findIndex($table, $columns, $unique, $db);

        if ($indexName) {
            $db->createCommand()
                ->dropIndex($indexName, $table)
                ->execute();
        }
    }

    /**
     * Creates and executes a SQL statement for dropping a foreign key if it exists.
     *
     * @param string $table The table that the foreign key was created for.
     * @param string|string[] $columns The column(s) that are included in the foreign key. If there are multiple columns, separate them
     * by commas or use an array.
     * @param Connection|null $db The database connection.
     * @since 4.0.0
     */
    public static function dropForeignKeyIfExists(
        string $table,
        string|array $columns,
        Connection|null $db = null,
    ): void {
        if ($db === null) {
            $db = self::db();
        }

        $fkName = static::findForeignKey($table, $columns, $db);

        if ($fkName) {
            $db->createCommand()
                ->dropForeignKey($fkName, $table)
                ->execute();
        }
    }

    /**
     * Drops all the foreign keys that reference a table.
     *
     * @param string $table The table that the foreign keys should reference.
     * @param Connection|null $db The database connection.
     * @since 4.0.0
     */
    public static function dropAllForeignKeysToTable(string $table, ?Connection $db = null): void
    {
        if ($db === null) {
            $db = self::db();
        }

        $schema = $db->getSchema();
        $rawTableName = $schema->getRawTableName($table);

        foreach ($schema->getTableSchemas() as $otherTable) {
            foreach ($otherTable->foreignKeys as $fkName => $fk) {
                if ($fk[0] === $rawTableName) {
                    $db->createCommand()
                        ->dropForeignKey($fkName, $otherTable->name)
                        ->execute();
                }
            }
        }
    }

    /**
     * Renames a table and its corresponding sequence (if PostgreSQL).
     *
     * @param string $table The table to be renamed.
     * @param string $newName The new table name.
     * @param Connection|null $db The database connection.
     * @since 4.0.0
     */
    public static function renameTable(string $table, string $newName, ?Connection $db = null): void
    {
        if ($db === null) {
            $db = self::db();
        }

        $schema = $db->getSchema();
        $rawOldName = $schema->getRawTableName($table);
        $rawNewName = $schema->getRawTableName($newName);

        // Rename the table
        $db->createCommand()
            ->renameTable($rawOldName, $rawNewName)
            ->execute();

        if ($db->getIsPgsql()) {
            // Rename the corresponding sequence if there is one
            // see https://www.postgresql.org/message-id/200308211224.06775.jgardner%40jonathangardner.net
            $transaction = $db->beginTransaction();
            try {
                $db->createCommand()
                    ->renameSequence("{$rawOldName}_id_seq", "{$rawNewName}_id_seq")
                    ->execute();
                $transaction->commit();
            } catch (Throwable) {
                // Silently fail. The sequence probably doesn't exist
                $transaction->rollBack();
            }
        }
    }

    /**
     * Returns the `id` of a row in the given table by its `uid`.
     *
     * @param string $table
     * @param string $uid
     * @param Connection|null $db The database connection to use
     * @return int|null
     * @since 3.1.0
     */
    public static function idByUid(string $table, string $uid, ?Connection $db = null): ?int
    {
        if ($db === null) {
            $db = self::db();
        }

        $id = (new Query())
            ->select(['id'])
            ->from([$table])
            ->where(['uid' => $uid])
            ->scalar($db);

        return (int)$id ?: null;
    }

    /**
     * Returns an array `uid`:`id` pairs from a given table, by their `uid`s.
     *
     * @param string $table
     * @param string[] $uids
     * @param Connection|null $db The database connection to use
     * @return int[]
     * @since 3.1.0
     */
    public static function idsByUids(string $table, array $uids, ?Connection $db = null): array
    {
        if ($db === null) {
            $db = self::db();
        }

        return (new Query())
            ->select(['uid', 'id'])
            ->from([$table])
            ->where(['uid' => $uids])
            ->pairs($db);
    }

    /**
     * Returns the `uid` of a row in the given table by its `id`.
     *
     * @param string $table
     * @param int $id
     * @param Connection|null $db The database connection to use
     * @return string|null
     * @since 3.1.0
     */
    public static function uidById(string $table, int $id, ?Connection $db = null): ?string
    {
        if ($db === null) {
            $db = self::db();
        }

        $uid = (new Query())
            ->select(['uid'])
            ->from([$table])
            ->where(['id' => $id])
            ->scalar($db);

        return $uid ?: null;
    }

    /**
     * Returns an array `id`:`uid` pairs from a given table, by their `id`s.
     *
     * @param string $table
     * @param int[] $ids
     * @param Connection|null $db The database connection to use
     * @return string[]
     * @since 3.1.0
     */
    public static function uidsByIds(string $table, array $ids, ?Connection $db = null): array
    {
        if ($db === null) {
            $db = self::db();
        }

        return (new Query())
            ->select(['id', 'uid'])
            ->from([$table])
            ->where(['id' => $ids])
            ->pairs($db);
    }

    /**
     * Parses a DSN string and returns an array with the `driver` and any driver params, or just a single key.
     *
     * @param string $dsn
     * @param string|null $key The key that is needed from the DSN, if only one param is needed.
     * @return array|string|false The full array, or the specific key value, or `false` if `$key` is a param that
     * doesn’t exist in the DSN string.
     * @throws InvalidArgumentException if $dsn is invalid
     * @since 3.4.0
     */
    public static function parseDsn(string $dsn, ?string $key = null): array|string|false
    {
        if (($pos = strpos($dsn, ':')) === false) {
            throw new InvalidArgumentException('Invalid DSN: ' . $dsn);
        }

        $driver = strtolower(substr($dsn, 0, $pos));
        if ($key === 'driver') {
            return $driver;
        }
        if ($key === null) {
            $parsed = [
                'driver' => $driver,
            ];
        }

        $params = substr($dsn, $pos + 1);
        foreach (ArrayHelper::filterEmptyStringsFromArray(explode(';', $params)) as $param) {
            [$n, $v] = array_pad(explode('=', $param, 2), 2, '');
            if ($key === $n) {
                return $v;
            }
            if ($key === null) {
                $parsed[$n] = $v;
            }
        }

        if ($key === null) {
            // todo: remove comment when phpstan#5401 is fixed
            /** @phpstan-ignore-next-line */
            return $parsed;
        }

        return false;
    }

    /**
     * Returns whether the database supports time zone conversions.
     *
     * This could return `false` if MySQL’s time zone tables haven’t been populated yet. See
     * https://dev.mysql.com/doc/refman/5.7/en/time-zone-support.html for more info.
     *
     * @param Connection|null $db
     * @return bool
     * @since 3.6.16
     */
    public static function supportsTimeZones(?Connection $db = null): bool
    {
        if ($db === null) {
            $db = self::db();
        }

        if ($db->getIsPgsql()) {
            return true;
        }

        $result = $db->createCommand("SELECT CONVERT_TZ('2007-03-11 02:00:00','America/Los_Angeles','America/New_York') AS time1")->queryScalar();
        return (bool)$result;
    }

    /**
     * Generates a DB config from a database connection URL.
     *
     * This can be used from `config/db.php`:
     * ---
     * ```php
     * $url = craft\helpers\App::env('CRAFT_DB_URL');
     * return craft\helpers\Db::url2config($url);
     * ```
     *
     * @param string $url
     * @return array
     * @since 3.4.0
     */
    public static function url2config(string $url): array
    {
        $parsed = parse_url($url);

        if (!isset($parsed['scheme'])) {
            throw new InvalidArgumentException('Invalid URL: ' . $url);
        }

        $config = [];

        // user & password
        if (isset($parsed['user'])) {
            $config['user'] = $parsed['user'];
        }
        if (isset($parsed['pass'])) {
            $config['password'] = $parsed['pass'];
        }

        // URL scheme => driver
        if (in_array(strtolower($parsed['scheme']), ['pgsql', 'postgres', 'postgresql'], true)) {
            $config['driver'] = Connection::DRIVER_PGSQL;
        } else {
            $config['driver'] = Connection::DRIVER_MYSQL;
        }

        // Other URL params
        $urlParams = [
            'host' => ['server', 'host'],
            'port' => ['port', 'port'],
            'path' => ['database', 'dbname'],
        ];
        $dsnParams = [];
        foreach ($urlParams as $urlParam => [$configKey, $dsnParam]) {
            if (isset($parsed[$urlParam])) {
                $value = trim($parsed[$urlParam], '/');
                $config[$configKey] = $value;
                $dsnParams[] = sprintf('%s=%s', $dsnParam, $value);
            }
        }

        $config['dsn'] = "{$config['driver']}:" . implode(';', $dsnParams);

        // Append any query params to the DSN
        if (isset($parsed['query'])) {
            $config['dsn'] .= ';' . $parsed['query'];
        }

        return $config;
    }

    /**
     * Returns the main application's DB connection.
     *
     * @return Connection
     */
    private static function db(): Connection
    {
        return self::$_db ?? (self::$_db = Craft::$app->getDb());
    }

    /**
     * @var Connection|null
     */
    private static ?Connection $_db = null;

    /**
     * Resets the memoized database connection.
     *
     * @since 3.5.12.1
     */
    public static function reset(): void
    {
        if (isset(self::$_db)) {
            self::$_db->close();
        }
        self::$_db = null;
    }

    /**
     * Normalizes “empty” values.
     *
     * @param mixed $value The param value.
     */
    private static function _normalizeEmptyValue(mixed &$value): void
    {
        if ($value === null) {
            $value = ':empty:';
            return;
        }

        if (!is_string($value) || $value === ':empty:' || $value === 'not :empty:') {
            return;
        }

        $lower = strtolower($value);

        if ($lower === ':empty:') {
            $value = ':empty:';
        } elseif ($lower === ':notempty:' || $lower === 'not :empty:') {
            $value = 'not :empty:';
        }
    }

    /**
     * Extracts the operator from a DB param and returns it.
     *
     * @param mixed $value Te param value.
     * @param string $default The default operator to use
     * @param bool $negate Whether to reverse whatever the selected operator is
     * @return string The operator ('!=', '<=', '>=', '<', '>', or '=')
     */
    private static function _parseParamOperator(mixed &$value, string $default, bool $negate = false): string
    {
        $op = null;

        if (is_string($value)) {
            foreach (self::$_operators as $operator) {
                // Does the value start with this operator?
                if (stripos($value, $operator) === 0) {
                    $value = mb_substr($value, strlen($operator));
                    $op = $operator === 'not ' ? '!=' : $operator;
                    break;
                }
                // Does it start with this operator, but escaped?
                if (stripos($value, "\\$operator") === 0) {
                    $value = substr($value, 1);
                    break;
                }
            }
        }

        if ($op === null) {
            $op = $default === 'not' || $default === 'not ' ? '!=' : $default;
        }

        if ($negate) {
            switch ($op) {
                case '!=':
                    return '=';
                case '<=':
                    return '>';
                case '>=':
                    return '<';
                case '<':
                    return '>=';
                case '>':
                    return '<=';
                case '=':
                    return '!=';
            }
        }

        return $op;
    }

    /**
     * @param string $column
     * @param array $values
     * @return array
     */
    private static function _inCondition(string $column, array $values): array
    {
        return [
            $column => count($values) === 1 ? $values[0] : $values,
        ];
    }

    /**
     * Starts a batch query, similar to [[YiiQuery::batch()]].
     *
     * Each iteration will be a batch of rows.
     *
     * ```php
     * foreach (Db::batch($query) as $batch) {
     *     foreach ($batch as $row) {
     *         // ...
     *     }
     * }
     * ```
     *
     * If using MySQL and `$db` is null, a new [unbuffered](https://www.php.net/manual/en/mysqlinfo.concepts.buffering.php)
     * DB connection will be created for the query so that the data can actually be retrieved in batches,
     * to work around [limitations](https://www.yiiframework.com/doc/guide/2.0/en/db-query-builder#batch-query-mysql)
     * with query batching in MySQL. Therefore keep in mind that the data retrieved by the batch query won’t
     * reflect any changes that have been made over the main DB connection, if a transaction is currently
     * active.
     *
     * @param QueryInterface $query The query that should be executed
     * @param int $batchSize The number of rows to be fetched in each batch
     * @return BatchQueryResult The batched query to be iterated on
     * @since 3.7.0
     */
    public static function batch(QueryInterface $query, int $batchSize = 100): BatchQueryResult
    {
        return self::_batch($query, $batchSize, false);
    }

    /**
     * Starts a batch query and retrieves data row by row.
     *
     * This method is similar to [[batch()]] except that in each iteration of the result,
     * only one row of data is returned.
     *
     * ```php
     * foreach (Db::each($query) as $row) {
     *     // ...
     * }
     * ```
     *
     * If using MySQL and `$db` is null, a new [unbuffered](https://www.php.net/manual/en/mysqlinfo.concepts.buffering.php)
     * DB connection will be created for the query so that the data can actually be retrieved in batches,
     * to work around [limitations](https://www.yiiframework.com/doc/guide/2.0/en/db-query-builder#batch-query-mysql)
     * with query batching in MySQL. Therefore keep in mind that the data retrieved by the batch query won’t
     * reflect any changes that have been made over the main DB connection, if a transaction is currently
     * active.
     *
     * @param QueryInterface $query The query that should be executed
     * @param int $batchSize The number of rows to be fetched in each batch
     * @return BatchQueryResult The batched query to be iterated on
     * @since 3.7.0
     */
    public static function each(QueryInterface $query, int $batchSize = 100): BatchQueryResult
    {
        return self::_batch($query, $batchSize, true);
    }

    /**
     * Starts a new batch query for batch() and each().
     *
     * @param QueryInterface $query
     * @param int $batchSize
     * @param bool $each
     * @return BatchQueryResult
     */
    private static function _batch(QueryInterface $query, int $batchSize, bool $each): BatchQueryResult
    {
        $db = self::db();
        $unbuffered = $db->getIsMysql() && Craft::$app->getConfig()->getDb()->useUnbufferedConnections;

        if ($unbuffered) {
            $db = Craft::$app->getComponents()['db'];
            if (!is_object($db) || is_callable($db)) {
                $db = Craft::createObject($db);
            }
            $db->on(Connection::EVENT_AFTER_OPEN, function() use ($db) {
                $db->pdo->setAttribute(PDO::MYSQL_ATTR_USE_BUFFERED_QUERY, false);
            });
        }

        /** @var BatchQueryResult $result */
        $result = Craft::createObject([
            'class' => BatchQueryResult::class,
            'query' => $query,
            'batchSize' => $batchSize,
            'db' => $db,
            'each' => $each,
        ]);

        if ($unbuffered) {
            $result->on(BatchQueryResult::EVENT_FINISH, function() use ($db) {
                $db->close();
            });
            $result->on(BatchQueryResult::EVENT_RESET, function() use ($db) {
                $db->close();
            });
        }

        return $result;
    }

    /**
     * Looks for an index on the given table with the given columns and unique property, and returns its name,
     * or null if no match is found.
     *
     * @param string $tableName The table that the index was created for.
     * @param string|string[] $columns The column(s) that are included in the index. If there are multiple
     * columns, separate them by commas or use an array.
     * @param bool $unique Whether the index has a UNIQUE constraint.
     * @param Connection|null $db The database connection.
     * @return string|null The index name, or `null` if there isn’t a matching one.
     * @since 4.0.0
     */
    public static function findIndex(
        string $tableName,
        string|array $columns,
        bool $unique = false,
        Connection|null $db = null,
    ): ?string {
        if (is_string($columns)) {
            $columns = StringHelper::split($columns);
        }

        if ($db === null) {
            $db = self::db();
        }

        foreach ($db->getSchema()->findIndexes($tableName) as $name => $index) {
            if ($index['columns'] === $columns && $index['unique'] === $unique) {
                return $name;
            }
        }

        return null;
    }

    /**
     * Looks for a foreign key on the given table with the given columns, and returns its name, or null if no
     * match is found.
     *
     * @param string $tableName The table that the foreign key is on
     * @param string|string[] $columns The column(s) that are included in the foreign key. If there are multiple
     * columns, separate them by commas or use an array.
     * @param Connection|null $db The database connection.
     * @return string|null The foreign key name, or `null` if there isn’t a matching one.
     * @since 4.0.0
     */
    public static function findForeignKey(
        string $tableName,
        string|array $columns,
        Connection|null $db = null,
    ): ?string {
        if (is_string($columns)) {
            $columns = StringHelper::split($columns);
        }

        if ($db === null) {
            $db = self::db();
        }

        $schema = $db->getSchema();
        $tableName = $schema->getRawTableName($tableName);
        $table = $schema->getTableSchema($tableName);

        foreach ($table->foreignKeys as $name => $fk) {
            $fkColumns = [];

            foreach ($fk as $count => $value) {
                if ($count !== 0) {
                    $fkColumns[] = $count;
                }
            }

            // Could be a composite key, so make sure all required values exist!
            if (count(array_intersect($fkColumns, $columns)) === count($columns)) {
                return $name;
            }
        }

        return null;
    }

    /**
     * Returns a table name with curly brackets and percent sign removed.
     *
     * @param string $name
     * @return string
     * @since 4.4.0
     */
    public static function rawTableShortName(string $name): string
    {
        // Based on Schema::getRawTableName(),
        // except we drop the % rather than replacing it with the table alias
        if (str_contains($name, '{{')) {
            $name = preg_replace('/\\{\\{(.*?)\\}\\}/', '\1', $name);
            // % could technically not be anywhere in the string
            return str_replace('%', '', $name);
        }

        return $name;
    }

    /**
     * Returns the default collation that should be used, based on the current MySQL version.
     *
     * - If MySQL 8.0+, `utf8mb4_0900_ai_ci` will be returned.
     * - Otherwise, `utf8mb4_unicode_ci` will be returned.
     *
     * @param Connection|null $db The database connection
     * @since 5.0.0
     */
    public static function defaultCollation(?Connection $db = null): string
    {
        if ($db === null) {
            $db = self::db();
        }

        if (!$db->getIsMaria() && version_compare($db->getServerVersion(), '8.0', '>=')) {
            return 'utf8mb4_0900_ai_ci';
        }

        return 'utf8mb4_unicode_ci';
    }
}
