1<?php
2/**
3 * `ALTER` statement.
4 */
5
6declare(strict_types=1);
7
8namespace PhpMyAdmin\SqlParser\Statements;
9
10use PhpMyAdmin\SqlParser\Components\AlterOperation;
11use PhpMyAdmin\SqlParser\Components\Expression;
12use PhpMyAdmin\SqlParser\Components\OptionsArray;
13use PhpMyAdmin\SqlParser\Parser;
14use PhpMyAdmin\SqlParser\Statement;
15use PhpMyAdmin\SqlParser\Token;
16use PhpMyAdmin\SqlParser\TokensList;
17
18use function implode;
19
20/**
21 * `ALTER` statement.
22 */
23class AlterStatement extends Statement
24{
25    /**
26     * Table affected.
27     *
28     * @var Expression
29     */
30    public $table;
31
32    /**
33     * Column affected by this statement.
34     *
35     * @var AlterOperation[]
36     */
37    public $altered = [];
38
39    /**
40     * Options of this statement.
41     *
42     * @var array
43     */
44    public static $OPTIONS = [
45        'ONLINE' => 1,
46        'OFFLINE' => 1,
47        'IGNORE' => 2,
48
49        'DATABASE' => 3,
50        'EVENT' => 3,
51        'FUNCTION' => 3,
52        'PROCEDURE' => 3,
53        'SERVER' => 3,
54        'TABLE' => 3,
55        'TABLESPACE' => 3,
56        'USER' => 3,
57        'VIEW' => 3,
58    ];
59
60    /**
61     * @param Parser     $parser the instance that requests parsing
62     * @param TokensList $list   the list of tokens to be parsed
63     */
64    public function parse(Parser $parser, TokensList $list)
65    {
66        ++$list->idx; // Skipping `ALTER`.
67        $this->options = OptionsArray::parse($parser, $list, static::$OPTIONS);
68        ++$list->idx;
69
70        // Parsing affected table.
71        $this->table = Expression::parse(
72            $parser,
73            $list,
74            [
75                'parseField' => 'table',
76                'breakOnAlias' => true,
77            ]
78        );
79        ++$list->idx; // Skipping field.
80
81        /**
82         * The state of the parser.
83         *
84         * Below are the states of the parser.
85         *
86         *      0 -----------------[ alter operation ]-----------------> 1
87         *
88         *      1 -------------------------[ , ]-----------------------> 0
89         *
90         * @var int
91         */
92        $state = 0;
93
94        for (; $list->idx < $list->count; ++$list->idx) {
95            /**
96             * Token parsed at this moment.
97             *
98             * @var Token
99             */
100            $token = $list->tokens[$list->idx];
101
102            // End of statement.
103            if ($token->type === Token::TYPE_DELIMITER) {
104                break;
105            }
106
107            // Skipping whitespaces and comments.
108            if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) {
109                continue;
110            }
111
112            if ($state === 0) {
113                $options = [];
114                if ($this->options->has('DATABASE')) {
115                    $options = AlterOperation::$DB_OPTIONS;
116                } elseif ($this->options->has('TABLE')) {
117                    $options = AlterOperation::$TABLE_OPTIONS;
118                } elseif ($this->options->has('VIEW')) {
119                    $options = AlterOperation::$VIEW_OPTIONS;
120                } elseif ($this->options->has('USER')) {
121                    $options = AlterOperation::$USER_OPTIONS;
122                }
123
124                $this->altered[] = AlterOperation::parse($parser, $list, $options);
125                $state = 1;
126            } elseif ($state === 1) {
127                if (($token->type === Token::TYPE_OPERATOR) && ($token->value === ',')) {
128                    $state = 0;
129                }
130            }
131        }
132    }
133
134    /**
135     * @return string
136     */
137    public function build()
138    {
139        $tmp = [];
140        foreach ($this->altered as $altered) {
141            $tmp[] = $altered::build($altered);
142        }
143
144        return 'ALTER ' . OptionsArray::build($this->options)
145            . ' ' . Expression::build($this->table)
146            . ' ' . implode(', ', $tmp);
147    }
148}
149