<?php
/*
	Copyright (c) TPsoft.org 2000-2025
	Author: Ing. Igor Mino <mino@tpsoft.org>
	License: GNU GPL-3.0 or later

	Description: Tool for automatic maintenance of database in your project.
	Version: 1.0.0

	Milestones:
	2025-05-29 07:59  Igor - Forked from Beteha to standalone public library
*/

namespace TPsoft\DBmodel;

class Maintenance
{
	public const ABNORMAL = 0;
	public const OK = 1;
	public const FIXED = 2;
	public const FIX_FAILED = 3;
	public const UPDATED = 4;
	public const UPDATE_FAIL = 5;

	public string $lastMessage = '';

	protected DBmodel $dbh;

	public function __construct(?DBmodel $dbh)
	{
		if (is_null($dbh)) {
			if (!is_null(DBmodel::$instance)) {
				$this->dbh = DBmodel::$instance;
			} else {
				throw new \Exception('DB handler is null');
			}
		} else {
			$this->dbh = $dbh;
		}
	}

	public function testDB($test, $test_out)
	{
		if (is_array($test_out)) {
			$test_out = array_change_key_case($test_out, CASE_LOWER);
			$row = $this->dbh->getRow($test);
			if (!is_array($row)) return false;
			$row = array_change_key_case($row, CASE_LOWER);
			foreach ($test_out as $col => $val) {
				if (strlen($row[$col]) != strlen($val)) {
					$max_len = min(strlen($row[$col]), strlen($val));
					if (substr(strtolower($row[$col]), 0, $max_len) != substr(strtolower($val), 0, $max_len)) {
						return false;
					}
				} else {
					if (strtolower($row[$col]) != strtolower($val)) {
						return false;
					}
				}
			}
			return true;
		} else {
			return $this->dbh->getOne($test) == $test_out;
		}
	}

	public function checkDB($test, $test_out, $fix)
	{
		if ($this->testDB($test, $test_out)) {
			return Maintenance::OK;
		} else {
			$this->dbh->query($fix);
			if ($this->testDB($test, $test_out)) {
				return Maintenance::FIXED;
			} else {
				return Maintenance::FIX_FAILED;
			}
		}
		return 0;
	}

	public function existsTable($table_name)
	{
		return $this->testDB(
			'SHOW TABLES LIKE "' . $table_name . '"',
			$table_name
		);
	}

	public function checkDBTable($table_name, $definition, $after_definition = '')
	{
		if (strlen($table_name) <= 0) {
			$this->lastMessage = 'Table ' . strtoupper($table_name) . ' - invalid index';
			return Maintenance::ABNORMAL;
		}
		$status = $this->checkDB(
			// TEST query
			'SHOW TABLES LIKE "' . $table_name . '"',
			// TEST output
			$table_name,
			// FIX query
			'CREATE TABLE `' . $table_name . '` (' . $definition . ') ' . $after_definition
		);
		$this->lastMessage = 'Table ' . strtoupper($table_name) . ' (' . $table_name . ')';
		return $status;
	}

	public function existsColumn($table_name, $column)
	{
		return $this->testDB(
			'DESCRIBE `' . $table_name . '` `' . $column . '`',
			$column
		);
	}

	public function checkDBAdd($table_name, $column, $definition)
	{
		$status = $this->checkDB(
			// TEST query
			'DESCRIBE `' . $table_name . '` `' . $column . '`',
			// TEST output
			$column,
			// FIX query
			'ALTER TABLE `' . $table_name . '` ADD `' . $column . '` ' . $definition
		);
		$this->lastMessage = "Added column $column to table $table_name";
		return $status;
	}

	public function checkDBRename($table_name, $column_old, $column_new, $definition, $test = null)
	{
		if (!$this->existsColumn($table_name, $column_old)) {
			return Maintenance::ABNORMAL;
		}
		$status = $this->checkDB(
			// TEST query
			'DESCRIBE `' . $table_name . '` `' . $column_old . '`',
			// TEST output
			$test,
			// FIX query
			'ALTER TABLE `' . $table_name . '` CHANGE `' . $column_old . '` `' . $column_new . '` ' . $definition
		);
		$this->lastMessage = "Renamed  column $column_old to $column_new for $table_name";
		return $status;
	}

	public function checkDBRetype($table_name, $column, $new_type, $definition)
	{
		if (!$this->existsColumn($table_name, $column)) {
			return Maintenance::ABNORMAL;
		}
		$status = $this->checkDB(
			// TEST query
			'DESCRIBE `' . $table_name . '` `' . $column . '`',
			// TEST output
			array('type' => strtolower($new_type)),
			// FIX query
			'ALTER TABLE `' . $table_name . '` CHANGE `' . $column . '` `' . $column . '` ' . $definition
		);
		$this->lastMessage = "Changed type of column $column for table " . strtoupper($table_name) . " to tyoe " . strtoupper($new_type);
		return $status;
	}

	public function checkDBRemove($table_name, $column)
	{
		$status = $this->checkDB(
			// TEST query
			'DESCRIBE `' . $table_name . '` `' . $column . '`',
			// TEST output
			NULL,
			// FIX query
			'ALTER TABLE `' . $table_name . '` DROP COLUMN `' . $column . '`'
		);
		$this->lastMessage = "Removed column $column for " . strtoupper($table_name);
		return $status;
	}

	public function addKey($table_name, $key)
	{
		$test = 'SHOW INDEX FROM `' . $table_name . '` WHERE column_name = "' . $key . '"';
		$test_out = array('table' => $table_name);
		if ($this->testDB($test, $test_out)) {
			$status = Maintenance::OK;
		} else {
			$fix = 'CREATE INDEX `' . $key . '` ON `' . $table_name . '` (`' . $key . '`)';
			$this->dbh->query($fix);
			if ($this->testDB($test, $test_out)) {
				$status = Maintenance::FIXED;
			} else {
				$status = Maintenance::FIX_FAILED;
			}
		}
		$this->lastMessage = 'Added KEY ' . $key . ' for ' . strtoupper($table_name);
		return $status;
	}

	public function dropKey($table_name, $key)
	{
		$test = 'SHOW INDEX FROM `' . $table_name . '` WHERE column_name = "' . $key . '"';
		$test_out = null;
		if ($this->testDB($test, $test_out)) {
			$status = Maintenance::OK;
		} else {
			$index_info = $this->dbh->getRow('SHOW INDEX FROM `' . $table_name . '` WHERE column_name = "' . $key . '"');
			$index_info = array_change_key_case($index_info, CASE_LOWER);
			$index_name = $index_info['key_name'];
			$fix = 'ALTER TABLE `' . $table_name . '` DROP INDEX `' . $index_name . '`';
			$this->dbh->query($fix);
			if ($this->testDB($test, $test_out)) {
				$status = Maintenance::FIXED;
			} else {
				$status = Maintenance::FIX_FAILED;
			}
		}
		$this->lastMessage = 'Deleted KEY ' . $key . ' for ' . strtoupper($table_name);
		return $status;
	}

	public function updateDB($test, $test_out, $update)
	{
		if (!$this->testDB($test, $test_out)) {
			return Maintenance::OK;
		} else {
			$suc = $this->dbh->query($update);
			if ($suc !== false) {
				return Maintenance::UPDATED;
			} else {
				return Maintenance::UPDATE_FAIL;
			}
		}
		return 0;
	}
}