<?php
use Index\Data\IDbConnection;
use Index\Data\Migration\IDbMigration;

final class InitialStructure_20231106_004121 implements IDbMigration {
    public function migrate(IDbConnection $conn): void {
        $existingTables = [];
        $result = $conn->query('SHOW TABLES');
        while($result->next())
            $existingTables[] = $result->getString(0);

        if(!in_array('exchange-rates', $existingTables))
            $conn->execute('
                CREATE TABLE `exchange-rates` (
                    rate_from BINARY(3) NOT NULL,
                    rate_to BINARY(3) NOT NULL,
                    rate_value DECIMAL(20,6) NOT NULL,
                    rate_stored TIMESTAMP NOT NULL DEFAULT current_timestamp(),
                    PRIMARY KEY (rate_from, rate_to),
                    KEY rate_stored (rate_stored)
                ) ENGINE=InnoDB COLLATE="utf8mb4_bin"
            ');
    }
}