<?php
/**
 * Jingga
 *
 * PHP Version 8.2
 *
 * @package   phpOMS\DataStorage\Database\Schema\Grammar
 * @copyright Dennis Eichhorn
 * @license   OMS License 2.2
 * @version   1.0.0
 * @link      https://jingga.app
 */
declare(strict_types=1);

namespace phpOMS\DataStorage\Database\Schema\Grammar;

use phpOMS\DataStorage\Database\BuilderAbstract;
use phpOMS\DataStorage\Database\Query\Builder;
use phpOMS\DataStorage\Database\Schema\Builder as SchemaBuilder;
use phpOMS\DataStorage\Database\Schema\QueryType;

/**
 * Database query grammar.
 *
 * @package phpOMS\DataStorage\Database\Schema\Grammar
 * @license OMS License 2.2
 * @link    https://jingga.app
 * @since   1.0.0
 */
class MysqlGrammar extends Grammar
{
    /**
     * System identifier.
     *
     * @var string
     * @since 1.0.0
     */
    public string $systemIdentifierStart = '`';

    /**
     * System identifier.
     *
     * @var string
     * @since 1.0.0
     */
    public string $systemIdentifierEnd = '`';

    /**
     * {@inheritdoc}
     */
    public function compilePostQueries(BuilderAbstract $query) : array
    {
        /** @var SchemaBuilder $query */

        $sql = [];
        switch ($query->getType()) {
            case QueryType::CREATE_TABLE:
                foreach ($query->createFields as $name => $field) {
                    if (isset($field['meta']['multi_autoincrement'])) {
                        $tmpSql = 'CREATE TRIGGER update_' . $name
                            . ' BEFORE INSERT ON ' . $query->createTable
                            . ' FOR EACH ROW BEGIN'
                            . ' SET NEW.' . $name . ' = ('
                                . 'SELECT COALESCE(MAX(' . $name . '), 0) + 1'
                                . ' FROM ' . $query->createTable
                                . ' WHERE';

                        foreach ($field['meta']['multi_autoincrement'] as $index => $autoincrement) {
                            $tmpSql .= ($index > 0 ? ' AND' : '') . ' ' . $autoincrement . ' = NEW.' . $autoincrement;
                        }

                        $tmpSql .= ' LIMIT 1); END;';

                        $sql[] = $tmpSql;
                    }
                }

                break;
            default:
                return [];
        }

        return $sql;
    }

    /**
     * Compile remove
     *
     * @param Builder $query  Builder
     * @param array   $remove Remove data
     *
     * @return string
     *
     * @since 1.0.0
     */
    protected function compileAlterRemove(BuilderAbstract $query, array $remove) : string
    {
        $keyWord = $remove['type'] === 'CONSTRAINT' ? 'FOREIGN KEY ' : 'COLUMN';

        return 'DROP ' . $keyWord . ' ' . $remove['identifier'];
    }

    /**
     * Compile from.
     *
     * @param SchemaBuilder $query Builder
     * @param array         $table Tables
     *
     * @return string
     *
     * @since 1.0.0
     */
    protected function compileSelectTables(SchemaBuilder $query, array $table) : string
    {
        $builder = new Builder($query->getConnection());
        $builder->select('table_name')
            ->from('information_schema.tables')
            ->where('table_schema', '=', $query->getConnection()->getDatabase());

        $sql = $builder->toSql();

        foreach ($builder->binds as $bind) {
            $query->bind($bind);
        }

        return \rtrim($sql, ';');
    }

    /**
     * Compile from.
     *
     * @param SchemaBuilder $query Builder
     * @param string        $table Tables
     *
     * @return string
     *
     * @since 1.0.0
     */
    protected function compileSelectFields(SchemaBuilder $query, string $table) : string
    {
        $builder = new Builder($query->getConnection());
        $builder->select('*')
            ->from('information_schema.columns')
            ->where('table_schema', '=', $query->getConnection()->getDatabase())
            ->andWhere('table_name', '=', $table);

        $sql = $builder->toSql();

        foreach ($builder->binds as $bind) {
            $query->bind($bind);
        }

        return \rtrim($sql, ';');
    }

    /**
     * Compile create table fields query.
     *
     * @param SchemaBuilder $query  Query
     * @param array         $fields Fields to create
     *
     * @return string
     *
     * @since 1.0.0
     */
    protected function compileCreateFields(SchemaBuilder $query, array $fields) : string
    {
        $fieldQuery = '';
        $keys       = '';

        foreach ($fields as $name => $field) {
            $fieldQuery .= ' ' . $this->expressionizeTableColumn([$name]) . ' ' . $field['type'];

            if (isset($field['default']) || ($field['default'] === null && ($field['null'] ?? false))) {
                $fieldQuery .= ' DEFAULT ' . $this->compileValue($query, $field['default']);
            }

            if ($field['null'] ?? false) {
                $fieldQuery .= ' ' . ($field['null'] ? '' : 'NOT ') . 'NULL';
            }

            if ($field['autoincrement'] ?? false) {
                $fieldQuery .= ' AUTO_INCREMENT';
            }

            $fieldQuery .= ',';

            if ($field['primary'] ?? false) {
                $keys .= ' PRIMARY KEY (' .  $this->expressionizeTableColumn([$name]) . '),';
            }

            if ($field['unique'] ?? false) {
                $keys .= ' UNIQUE KEY (' .  $this->expressionizeTableColumn([$name]) . '),';
            }

            if (isset($field['foreignTable'], $field['foreignKey'])) {
                $keys .= ' FOREIGN KEY (' .  $this->expressionizeTableColumn([$name]) . ') REFERENCES '
                    . $this->expressionizeTableColumn([$field['foreignTable']])
                    . ' (' . $this->expressionizeTableColumn([$field['foreignKey']]) . '),';
            }

            if (isset($field['meta']['multi_autoincrement'])) {
                $query->hasPostQuery = true;
            }
        }

        return '(' . \ltrim(\rtrim($fieldQuery . $keys, ','), ' ') . ')';
    }

    /**
     * Compile create table settings query.
     *
     * @param BuilderAbstract $query    Query
     * @param bool            $settings Has settings
     *
     * @return string
     *
     * @since 1.0.0
     */
    protected function compileCreateTableSettings(BuilderAbstract $query, bool $settings) : string
    {
        return 'ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 AUTO_INCREMENT=1';
    }
}