Helix\DB\Schema

Complexity

Total Complexity

33

Size/Duplication

Total Lines	499
Duplicated Lines	0 %

Importance

Changes	1
Bugs	0	Features	0

23 Methods

Rating	Name	Duplication	Size	Complexity
A	dropTable()	0	3	1
A	offsetUnset()	0	2	1
A	toUniqueKeyConstraint()	0	5	1
A	createJunctionTable()	0	5	1
A	offsetExists()	0	2	1
A	dropColumn()	0	4	1
A	toColumnDefinitions()	0	17	3
A	getTable()	0	17	4
A	toUniqueKeyConstraint_name()	0	3	1
A	offsetSet()	0	2	1
A	createRecordTable()	0	8	2
A	offsetGet()	0	2	1
A	toPrimaryKeyConstraint_name()	0	3	1
A	renameColumn()	0	4	1
A	renameTable()	0	4	1
A	createTable()	0	27	4
A	toForeignKeyConstraint()	0	7	1
A	createEavTable()	0	9	1
A	sortColumns()	0	6	2
A	__construct()	0	3	1
A	addColumn()	0	5	1
A	toPrimaryKeyConstraint()	0	5	1
A	toForeignKeyConstraint_name()	0	2	1

<?php

namespace Helix\DB;

use ArrayAccess;
use Helix\DB;
use LogicException;

/**
 * Schema control and metadata.
 *
 * The column definition constants are two bytes each, used in bitwise composition.
 * - The high-byte (`<I_CONST>`) is used for the specific index type.
 *      - Descending index priority. For example, `I_PRIMARY` is `0x8000` (highest bit)
 * - The low-byte (`<T_CONST>`) is used for the specific storage type.
 *      - Inverse size complexity. For example, `BOOL` is `0x0080`, and `T_BLOB` is `0x0002`
 *      - The final bit `0x0001` flags nullability.
 *      - Bit `0x0010` is reserved for future use (probably `DateTime`).
 * - The literal values may change in the future, do not hard code them.
 * - The values may expand to use a total of 4 or 8 bytes to accommodate more stuff.
 *
 * @method static static factory(DB $db)
 */
class Schema implements ArrayAccess {

    use FactoryTrait;

    /**
     * `<TABLE_CONST>`: Multi-column primary key.
     */
    const TABLE_PRIMARY = 0;

    /**
     * `<TABLE_CONST>`: Associative foreign keys.
     */
    const TABLE_FOREIGN = 1;

    /**
     * `<TABLE_CONST>`: Groups of columns are unique together.
     */
    const TABLE_UNIQUE = 2;

    /**
     * Higher byte mask (column index type).
     */
    protected const I_MASK = 0xFF00;

    /**
     * `<I_CONST>`: Column is the primary key.
     */
    const I_PRIMARY = 0x8000;

    /**
     * `<I_CONST>`: Column is the primary key and auto-increments.
     */
    const I_AUTOINCREMENT = 0x4000 | self::I_PRIMARY;

    /**
     * `<I_CONST>`: Column is unique.
     */
    const I_UNIQUE = 0x2000;

    /**
     * Lower-byte mask (column storage type).
     */
    protected const T_MASK = 0x00FF;

    /**
     * `<T_CONST>`: Column is the primary key and auto-increments (8-byte signed integer).
     */
    const T_AUTOINCREMENT = self::I_AUTOINCREMENT | self::T_INT_STRICT;

    /**
     * Flags whether a type is `NOT NULL`
     */
    protected const T_STRICT = 0x0001;

    /**
     * `<T_CONST>`: Boolean analog (numeric).
     */
    const T_BOOL = 0x0080;
    const T_BOOL_STRICT = self::T_BOOL | self::T_STRICT;

    /**
     * `<T_CONST>`: 8-byte signed integer.
     */
    const T_INT = 0x0040;
    const T_INT_STRICT = self::T_INT | self::T_STRICT;

    /**
     * `<T_CONST>`: 8-byte IEEE floating point number.
     */
    const T_FLOAT = 0x0020;
    const T_FLOAT_STRICT = self::T_FLOAT | self::T_STRICT;

    /**
     * `<T_CONST>`: UTF-8 up to 255 bytes.
     */
    const T_STRING = 0x0008;
    const T_STRING_STRICT = self::T_STRING | self::T_STRICT;

    /**
     * `<T_CONST>`: UTF-8 up to 64KiB.
     */
    const T_TEXT = 0x0004;
    const T_TEXT_STRICT = self::T_TEXT | self::T_STRICT;

    /**
     * `<T_CONST>`: Arbitrary binary data up to 4GiB.
     */
    const T_BLOB = 0x0002;
    const T_BLOB_STRICT = self::T_BLOB | self::T_STRICT;

    /**
     * Maps native/annotated types to storage types.
     */
    protected const PHP_TYPES = [
        'bool' => self::T_BOOL,
        'double' => self::T_FLOAT,
        'float' => self::T_FLOAT,
        'int' => self::T_INT,
        'string' => self::T_STRING,
        'String' => self::T_TEXT,
        'STRING' => self::T_BLOB
    ];
    /**
     * Driver-specific schema phrases.
     */
    protected const COLUMN_DEFINITIONS = [
        'mysql' => [
            self::I_AUTOINCREMENT => 'PRIMARY KEY AUTO_INCREMENT',
            self::I_PRIMARY => 'PRIMARY KEY',
            self::I_UNIQUE => 'UNIQUE',
            self::T_BLOB => 'LONGBLOB NULL DEFAULT NULL',
            self::T_BOOL => 'BOOLEAN NULL DEFAULT NULL',
            self::T_FLOAT => 'DOUBLE PRECISION NULL DEFAULT NULL',
            self::T_INT => 'BIGINT NULL DEFAULT NULL',
            self::T_STRING => 'VARCHAR(255) NULL DEFAULT NULL',
            self::T_TEXT => 'TEXT NULL DEFAULT NULL',
            self::T_BLOB_STRICT => 'LONGBLOB NOT NULL',
            self::T_BOOL_STRICT => 'BOOLEAN NOT NULL',
            self::T_FLOAT_STRICT => 'DOUBLE PRECISION NOT NULL',
            self::T_INT_STRICT => 'BIGINT NOT NULL',
            self::T_STRING_STRICT => 'VARCHAR(255) NOT NULL',
            self::T_TEXT_STRICT => 'TEXT NOT NULL',
        ],
        'sqlite' => [
            self::I_AUTOINCREMENT => 'PRIMARY KEY AUTOINCREMENT',
            self::I_PRIMARY => 'PRIMARY KEY',
            self::I_UNIQUE => 'UNIQUE',
            self::T_BLOB => 'BLOB DEFAULT NULL',
            self::T_BOOL => 'BOOLEAN DEFAULT NULL',
            self::T_FLOAT => 'REAL DEFAULT NULL',
            self::T_INT => 'INTEGER DEFAULT NULL',
            self::T_STRING => 'TEXT DEFAULT NULL',
            self::T_TEXT => 'TEXT DEFAULT NULL',
            self::T_BLOB_STRICT => 'BLOB NOT NULL',
            self::T_BOOL_STRICT => 'BOOLEAN NOT NULL',
            self::T_FLOAT_STRICT => 'REAL NOT NULL',
            self::T_INT_STRICT => 'INTEGER NOT NULL',
            self::T_STRING_STRICT => 'TEXT NOT NULL',
            self::T_TEXT_STRICT => 'TEXT NOT NULL',
        ]
    ];

    /**
     * @var int[]
     */
    protected $colDefs;

    /**
     * @var DB
     */
    protected $db;

    /**
     * @var Table[]
     */
    protected $tables = [];

    /**
     * @param DB $db
     */
    public function __construct (DB $db) {
        $this->db = $db;
        $this->colDefs ??= self::COLUMN_DEFINITIONS[$db->getDriver()];
    }

    /**
     * `ALTER TABLE $table ADD COLUMN $column ...`
     *
     * @param string $table
     * @param string $column
     * @param int $type
     * @return $this
     */
    public function addColumn (string $table, string $column, int $type = self::T_STRING) {
        $type = $this->colDefs[$type & self::T_MASK];
        $this->db->exec("ALTER TABLE {$table} ADD COLUMN {$column} {$type}");
        unset($this->tables[$table]);
        return $this;
    }

    /**
     * Creates the underlying storage for an {@link EAV}
     *
     * @param Record $record From {@link DB::getRecord()}
     * @param string $property The EAV property name in the record.
     * @return $this
     */
    public function createEavTable (Record $record, string $property) {
        $eav = $record->getEav($property);
        return $this->createTable($eav, [
            'entity' => self::T_INT_STRICT,
            'attribute' => self::T_STRING_STRICT,
            'value' => self::PHP_TYPES[$eav->getValueType()],
        ], [
            self::TABLE_PRIMARY => ['entity', 'attribute'],
            self::TABLE_FOREIGN => ['entity' => $record['id']]
        ]);
    }

    /**
     * Creates the underlying storage for a {@link Junction}
     *
     * @param Junction $junction From {@link DB::getJunction()}
     * @return $this
     */
    public function createJunctionTable (Junction $junction) {
        $records = $junction->getRecords();
        return $this->createTable($junction, array_map(fn() => self::T_INT_STRICT, $records), [
            self::TABLE_PRIMARY => array_keys($records),
            self::TABLE_FOREIGN => array_map(fn(Record $record) => $record['id'], $records)
        ]);
    }

    /**
     * Creates the underlying storage for a {@link Record}
     *
     * @param Record $record From {@link DB::getRecord()}
     * @param array[] $constraints See {@link Schema::createTable()}
     * @return $this
     */
    public function createRecordTable (Record $record, array $constraints = []) {
        $columns = $record->getTypes();
        array_walk($columns, function(string &$type, string $property) use ($record) {
            $type = self::PHP_TYPES[$type] | ($record->isNullable($property) ? 0 : self::T_STRICT);
        });
        $columns['id'] = self::T_AUTOINCREMENT; // force to autoincrement
        unset($constraints[self::TABLE_PRIMARY]); // `id` is the sole pk
        return $this->createTable($record, $columns, $constraints);
    }

    /**
     * `CREATE TABLE $table ...`
     *
     * At least one column must be given.
     *
     * `$constraints` is a multidimensional array of table-level constraints.
     * - `C_PRIMARY => [col, col, col]`
     *      - A list of columns composing the primary key.
     * - `C_UNIQUE => [ [col, col, col] , ... ]`
     *      - One or more column groups, each group composing a unique key.
     * - `C_FOREIGN => [ local column => <Column> ]`
     *      - Associative local columns that are each foreign keys to a {@link Column}
     *
     * @param string $table
     * @param int[] $columns `[ name => <I_CONST> | <T_CONST> ]`
     * @param array[] $constraints `[ <TABLE_CONST> => table constraint spec ]`
     * @return $this
     */
    public function createTable (string $table, array $columns, array $constraints = []) {
        $defs = $this->toColumnDefinitions($columns);

        /** @var string[] $pk */
        if ($pk = $constraints[self::TABLE_PRIMARY] ?? []) {
            $defs[] = $this->toPrimaryKeyConstraint($table, $pk);
        }

        /** @var string[] $unique */
        foreach ($constraints[self::TABLE_UNIQUE] ?? [] as $unique) {
            $defs[] = $this->toUniqueKeyConstraint($table, $unique);
        }

        /** @var string $local */
        /** @var Column $foreign */
        foreach ($constraints[self::TABLE_FOREIGN] ?? [] as $local => $foreign) {
            $defs[] = $this->toForeignKeyConstraint($table, $local, $foreign);
        }

        $sql = sprintf(
            "CREATE TABLE %s (%s)",
            $table,
            implode(', ', $defs)
        );

        $this->db->exec($sql);
        return $this;
    }

    /**
     * `ALTER TABLE $table DROP COLUMN $column`
     *
     * @param string $table
     * @param string $column
     * @return $this
     */
    public function dropColumn (string $table, string $column) {
        $this->db->exec("ALTER TABLE {$table} DROP COLUMN {$column}");
        unset($this->tables[$table]);
        return $this;
    }

    /**
     * `DROP TABLE IF EXISTS $table`
     *
     * @param string $table
     */
    public function dropTable (string $table): void {
        $this->db->exec("DROP TABLE IF EXISTS {$table}");
        unset($this->tables[$table]);
    }

    /**
     * @param string $name
     * @return null|Table
     */
    public function getTable (string $name) {
        if (!isset($this->tables[$name])) {
            if ($this->db->isSQLite()) {
                $info = $this->db->query("PRAGMA table_info({$name})")->fetchAll();
                $cols = array_column($info, 'name');
            }
            else {
                $cols = $this->db->query(
                    "SELECT column_name FROM information_schema.tables WHERE table_name = \"{$name}\""
                )->fetchAll(DB::FETCH_COLUMN);
            }
            if (!$cols) {

The expression $cols of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using empty($expr) instead to make it clear that you intend to check for an array without elements.

                return null;
            }
            $this->tables[$name] = Table::factory($this->db, $name, $cols);
        }
        return $this->tables[$name];
    }

    /**
     * Whether a table exists.
     *
     * @param string $table
     * @return bool
     */
    final public function offsetExists ($table): bool {
        return (bool)$this->offsetGet($table);
    }

    /**
     * Returns a table by name.
     *
     * @param string $table
     * @return null|Table
     */
    public function offsetGet ($table) {
        return $this->getTable($table);
    }

    /**
     * @param $offset
     * @param $value
     * @throws LogicException
     */
    final public function offsetSet ($offset, $value) {
        throw new LogicException('The schema cannot be altered this way.');
    }

    /**
     * @param $offset
     * @throws LogicException
     */
    final public function offsetUnset ($offset) {
        throw new LogicException('The schema cannot be altered this way.');
    }

    /**
     * `ALTER TABLE $table RENAME COLUMN $oldName TO $newName`
     *
     * @param string $table
     * @param string $oldName
     * @param string $newName
     * @return $this
     */
    public function renameColumn (string $table, string $oldName, string $newName) {
        $this->db->exec("ALTER TABLE {$table} RENAME COLUMN {$oldName} TO {$newName}");
        unset($this->tables[$table]);
        return $this;
    }

    /**
     * `ALTER TABLE $oldName RENAME TO $newName`
     *
     * @param string $oldName
     * @param string $newName
     * @return $this
     */
    public function renameTable (string $oldName, string $newName) {
        $this->db->exec("ALTER TABLE {$oldName} RENAME TO {$newName}");
        unset($this->tables[$oldName]);
        return $this;
    }

    /**
     * Sorts according to index priority, storage size/complexity, and name.
     *
     * @param int[] $types
     * @return int[]
     */
    protected function sortColumns (array $types): array {
        uksort($types, function(string $a, string $b) use ($types) {
            // descending index priority, increasing size, name
            return $types[$b] <=> $types[$a] ?: $a <=> $b;
        });
        return $types;
    }

    /**
     * @param int[] $columns `[ name => <I_CONST> | <T_CONST> ]`
     * @return string[]
     */
    protected function toColumnDefinitions (array $columns): array {
        assert(count($columns) > 0);
        $columns = $this->sortColumns($columns);
        $defs = [];

        /**
         * @var string $name
         * @var int $type
         */
        foreach ($columns as $name => $type) {
            $defs[$name] = sprintf("%s %s", $name, $this->colDefs[$type & self::T_MASK]);
            if ($indexSql = $type & self::I_MASK) {
                $defs[$name] .= " {$this->colDefs[$indexSql]}";
            }
        }

        return $defs;
    }

    /**
     * @param string $table
     * @param string $local
     * @param Column $foreign
     * @return string
     */
    protected function toForeignKeyConstraint (string $table, string $local, Column $foreign): string {
        return sprintf(
            'CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s(%s) ON DELETE CASCADE',
            $this->toForeignKeyConstraint_name($table, $local),
            $local,
            $foreign->getQualifier(),
            $foreign->getName()
        );
    }

    /**
     * `FK_TABLE__COLUMN__COLUMN__COLUMN`
     *
     * @param string $table
     * @param string $column
     * @return string
     */
    protected function toForeignKeyConstraint_name (string $table, string $column): string {
        return 'FK_' . $table . '__' . $column;
    }

    /**
     * @param string $table
     * @param string[] $columns
     * @return string
     */
    protected function toPrimaryKeyConstraint (string $table, array $columns): string {
        return sprintf(
            'CONSTRAINT %s PRIMARY KEY (%s)',
            $this->toPrimaryKeyConstraint_name($table, $columns),
            implode(',', $columns)
        );
    }

    /**
     * `PK_TABLE__COLUMN__COLUMN__COLUMN`
     *
     * @param string $table
     * @param string[] $columns
     * @return string
     */
    protected function toPrimaryKeyConstraint_name (string $table, array $columns): string {
        sort($columns, SORT_STRING);
        return 'PK_' . $table . '__' . implode('__', $columns);
    }

    /**
     * @param string $table
     * @param string[] $columns
     * @return string
     */
    protected function toUniqueKeyConstraint (string $table, array $columns): string {
        return sprintf(
            'CONSTRAINT %s UNIQUE (%s)',
            $this->toUniqueKeyConstraint_name($table, $columns),
            implode(',', $columns)
        );
    }

    /**
     * `UQ_TABLE__COLUMN__COLUMN__COLUMN`
     *
     * @param string $table
     * @param string[] $columns
     * @return string
     */
    protected function toUniqueKeyConstraint_name (string $table, array $columns): string {
        sort($columns, SORT_STRING);
        return 'UQ_' . $table . '__' . implode('__', $columns);
    }
}