1
|
|
|
<?php |
2
|
|
|
|
3
|
|
|
declare(strict_types=1); |
4
|
|
|
|
5
|
|
|
namespace PhpMyAdmin\SqlParser\Components; |
6
|
|
|
|
7
|
|
|
use PhpMyAdmin\SqlParser\Component; |
8
|
|
|
use PhpMyAdmin\SqlParser\Context; |
9
|
|
|
use PhpMyAdmin\SqlParser\Parser; |
10
|
|
|
use PhpMyAdmin\SqlParser\Token; |
11
|
|
|
use PhpMyAdmin\SqlParser\TokensList; |
12
|
|
|
|
13
|
|
|
use function count; |
14
|
|
|
|
15
|
|
|
/** |
16
|
|
|
* Parses a reference to a CASE expression. |
17
|
|
|
*/ |
18
|
|
|
final class CaseExpression implements Component |
19
|
|
|
{ |
20
|
|
|
/** |
21
|
|
|
* The value to be compared. |
22
|
|
|
* |
23
|
|
|
* @var Expression|null |
24
|
|
|
*/ |
25
|
|
|
public $value; |
26
|
|
|
|
27
|
|
|
/** |
28
|
|
|
* The conditions in WHEN clauses. |
29
|
|
|
* |
30
|
|
|
* @var Condition[][] |
31
|
|
|
*/ |
32
|
|
|
public $conditions = []; |
33
|
|
|
|
34
|
|
|
/** |
35
|
|
|
* The results matching with the WHEN clauses. |
36
|
|
|
* |
37
|
|
|
* @var Expression[] |
38
|
|
|
*/ |
39
|
|
|
public $results = []; |
40
|
|
|
|
41
|
|
|
/** |
42
|
|
|
* The values to be compared against. |
43
|
|
|
* |
44
|
|
|
* @var Expression[] |
45
|
|
|
*/ |
46
|
|
|
public $compareValues = []; |
47
|
|
|
|
48
|
|
|
/** |
49
|
|
|
* The result in ELSE section of expr. |
50
|
|
|
* |
51
|
|
|
* @var Expression|null |
52
|
|
|
*/ |
53
|
|
|
public $elseResult; |
54
|
|
|
|
55
|
|
|
/** |
56
|
|
|
* The alias of this CASE statement. |
57
|
|
|
* |
58
|
|
|
* @var string|null |
59
|
|
|
*/ |
60
|
|
|
public $alias; |
61
|
|
|
|
62
|
|
|
/** |
63
|
|
|
* The sub-expression. |
64
|
|
|
* |
65
|
|
|
* @var string |
66
|
|
|
*/ |
67
|
|
|
public $expr = ''; |
68
|
|
|
|
69
|
|
|
/** |
70
|
|
|
* @param Parser $parser the parser that serves as context |
71
|
|
|
* @param TokensList $list the list of tokens that are being parsed |
72
|
|
|
* @param array<string, mixed> $options parameters for parsing |
73
|
|
|
* |
74
|
|
|
* @return CaseExpression |
75
|
|
|
*/ |
76
|
64 |
|
public static function parse(Parser $parser, TokensList $list, array $options = []) |
77
|
|
|
{ |
78
|
64 |
|
$ret = new static(); |
79
|
|
|
|
80
|
|
|
/** |
81
|
|
|
* State of parser. |
82
|
|
|
* |
83
|
|
|
* @var int |
84
|
|
|
*/ |
85
|
64 |
|
$state = 0; |
86
|
|
|
|
87
|
|
|
/** |
88
|
|
|
* Syntax type (type 0 or type 1). |
89
|
|
|
* |
90
|
|
|
* @var int |
91
|
|
|
*/ |
92
|
64 |
|
$type = 0; |
93
|
|
|
|
94
|
64 |
|
++$list->idx; // Skip 'CASE' |
95
|
|
|
|
96
|
64 |
|
for (; $list->idx < $list->count; ++$list->idx) { |
97
|
|
|
/** |
98
|
|
|
* Token parsed at this moment. |
99
|
|
|
*/ |
100
|
64 |
|
$token = $list->tokens[$list->idx]; |
101
|
|
|
|
102
|
|
|
// Skipping whitespaces and comments. |
103
|
64 |
|
if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) { |
104
|
64 |
|
continue; |
105
|
|
|
} |
106
|
|
|
|
107
|
64 |
|
if ($state === 0) { |
108
|
64 |
|
if ($token->type === Token::TYPE_KEYWORD) { |
109
|
48 |
|
switch ($token->keyword) { |
110
|
48 |
|
case 'WHEN': |
111
|
30 |
|
++$list->idx; // Skip 'WHEN' |
112
|
30 |
|
$newCondition = Condition::parse($parser, $list); |
113
|
30 |
|
$type = 1; |
114
|
30 |
|
$state = 1; |
115
|
30 |
|
$ret->conditions[] = $newCondition; |
116
|
30 |
|
break; |
117
|
46 |
|
case 'ELSE': |
118
|
16 |
|
++$list->idx; // Skip 'ELSE' |
119
|
16 |
|
$ret->elseResult = Expression::parse($parser, $list); |
120
|
16 |
|
$state = 0; // last clause of CASE expression |
121
|
16 |
|
break; |
122
|
46 |
|
case 'END': |
123
|
44 |
|
$state = 3; // end of CASE expression |
124
|
44 |
|
++$list->idx; |
125
|
44 |
|
break 2; |
126
|
|
|
default: |
127
|
2 |
|
$parser->error('Unexpected keyword.', $token); |
128
|
32 |
|
break 2; |
129
|
|
|
} |
130
|
|
|
} else { |
131
|
32 |
|
$ret->value = Expression::parse($parser, $list); |
132
|
32 |
|
$type = 0; |
133
|
62 |
|
$state = 1; |
134
|
|
|
} |
135
|
62 |
|
} elseif ($state === 1) { |
136
|
62 |
|
if ($type === 0) { |
137
|
32 |
|
if ($token->type === Token::TYPE_KEYWORD) { |
138
|
32 |
|
switch ($token->keyword) { |
139
|
32 |
|
case 'WHEN': |
140
|
28 |
|
++$list->idx; // Skip 'WHEN' |
141
|
28 |
|
$newValue = Expression::parse($parser, $list); |
142
|
28 |
|
$state = 2; |
143
|
28 |
|
$ret->compareValues[] = $newValue; |
144
|
28 |
|
break; |
145
|
30 |
|
case 'ELSE': |
146
|
16 |
|
++$list->idx; // Skip 'ELSE' |
147
|
16 |
|
$ret->elseResult = Expression::parse($parser, $list); |
148
|
16 |
|
$state = 0; // last clause of CASE expression |
149
|
16 |
|
break; |
150
|
14 |
|
case 'END': |
151
|
10 |
|
$state = 3; // end of CASE expression |
152
|
10 |
|
++$list->idx; |
153
|
10 |
|
break 2; |
154
|
|
|
default: |
155
|
4 |
|
$parser->error('Unexpected keyword.', $token); |
156
|
32 |
|
break 2; |
157
|
|
|
} |
158
|
|
|
} |
159
|
|
|
} else { |
160
|
30 |
|
if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'THEN') { |
161
|
28 |
|
++$list->idx; // Skip 'THEN' |
162
|
28 |
|
$newResult = Expression::parse($parser, $list); |
163
|
28 |
|
$state = 0; |
164
|
28 |
|
$ret->results[] = $newResult; |
165
|
2 |
|
} elseif ($token->type === Token::TYPE_KEYWORD) { |
166
|
2 |
|
$parser->error('Unexpected keyword.', $token); |
167
|
58 |
|
break; |
168
|
|
|
} |
169
|
|
|
} |
170
|
28 |
|
} elseif ($state === 2) { |
171
|
28 |
|
if ($type === 0) { |
172
|
28 |
|
if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'THEN') { |
173
|
28 |
|
++$list->idx; // Skip 'THEN' |
174
|
28 |
|
$newResult = Expression::parse($parser, $list); |
175
|
28 |
|
$ret->results[] = $newResult; |
176
|
28 |
|
$state = 1; |
177
|
2 |
|
} elseif ($token->type === Token::TYPE_KEYWORD) { |
178
|
2 |
|
$parser->error('Unexpected keyword.', $token); |
179
|
2 |
|
break; |
180
|
|
|
} |
181
|
|
|
} |
182
|
|
|
} |
183
|
|
|
} |
184
|
|
|
|
185
|
64 |
|
if ($state !== 3) { |
186
|
10 |
|
$parser->error('Unexpected end of CASE expression', $list->tokens[$list->idx - 1]); |
187
|
|
|
} else { |
188
|
|
|
// Parse for alias of CASE expression |
189
|
54 |
|
$asFound = false; |
190
|
54 |
|
for (; $list->idx < $list->count; ++$list->idx) { |
191
|
54 |
|
$token = $list->tokens[$list->idx]; |
192
|
|
|
|
193
|
|
|
// End of statement. |
194
|
54 |
|
if ($token->type === Token::TYPE_DELIMITER) { |
195
|
20 |
|
break; |
196
|
|
|
} |
197
|
|
|
|
198
|
|
|
// Skipping whitespaces and comments. |
199
|
40 |
|
if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) { |
200
|
40 |
|
continue; |
201
|
|
|
} |
202
|
|
|
|
203
|
|
|
// Handle optional AS keyword before alias |
204
|
40 |
|
if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'AS') { |
205
|
20 |
|
if ($asFound || ! empty($ret->alias)) { |
206
|
2 |
|
$parser->error('Potential duplicate alias of CASE expression.', $token); |
207
|
2 |
|
break; |
208
|
|
|
} |
209
|
|
|
|
210
|
20 |
|
$asFound = true; |
211
|
20 |
|
continue; |
212
|
|
|
} |
213
|
|
|
|
214
|
|
|
if ( |
215
|
36 |
|
$asFound |
216
|
36 |
|
&& $token->type === Token::TYPE_KEYWORD |
217
|
36 |
|
&& ($token->flags & Token::FLAG_KEYWORD_RESERVED || $token->flags & Token::FLAG_KEYWORD_FUNCTION) |
218
|
|
|
) { |
219
|
2 |
|
$parser->error('An alias expected after AS but got ' . $token->value, $token); |
220
|
2 |
|
$asFound = false; |
221
|
2 |
|
break; |
222
|
|
|
} |
223
|
|
|
|
224
|
|
|
if ( |
225
|
34 |
|
$asFound |
226
|
32 |
|
|| $token->type === Token::TYPE_STRING |
227
|
32 |
|
|| ($token->type === Token::TYPE_SYMBOL && ! $token->flags & Token::FLAG_SYMBOL_VARIABLE) |
228
|
34 |
|
|| $token->type === Token::TYPE_NONE |
229
|
|
|
) { |
230
|
|
|
// An alias is expected (the keyword `AS` was previously found). |
231
|
20 |
|
if (! empty($ret->alias)) { |
232
|
2 |
|
$parser->error('An alias was previously found.', $token); |
233
|
2 |
|
break; |
234
|
|
|
} |
235
|
|
|
|
236
|
20 |
|
$ret->alias = $token->value; |
237
|
20 |
|
$asFound = false; |
238
|
|
|
|
239
|
20 |
|
continue; |
240
|
|
|
} |
241
|
|
|
|
242
|
28 |
|
break; |
243
|
|
|
} |
244
|
|
|
|
245
|
54 |
|
if ($asFound) { |
246
|
4 |
|
$parser->error('An alias was expected after AS.', $list->tokens[$list->idx - 1]); |
247
|
|
|
} |
248
|
|
|
|
249
|
54 |
|
$ret->expr = self::build($ret); |
250
|
|
|
} |
251
|
|
|
|
252
|
64 |
|
--$list->idx; |
253
|
|
|
|
254
|
64 |
|
return $ret; |
255
|
|
|
} |
256
|
|
|
|
257
|
|
|
/** |
258
|
|
|
* @param CaseExpression $component the component to be built |
259
|
|
|
* @param array<string, mixed> $options parameters for building |
260
|
|
|
*/ |
261
|
56 |
|
public static function build($component, array $options = []): string |
262
|
|
|
{ |
263
|
56 |
|
$ret = 'CASE '; |
264
|
56 |
|
if (isset($component->value)) { |
265
|
|
|
// Syntax type 0 |
266
|
26 |
|
$ret .= $component->value . ' '; |
267
|
26 |
|
$valuesCount = count($component->compareValues); |
268
|
26 |
|
$resultsCount = count($component->results); |
269
|
26 |
|
for ($i = 0; $i < $valuesCount && $i < $resultsCount; ++$i) { |
270
|
26 |
|
$ret .= 'WHEN ' . $component->compareValues[$i] . ' '; |
271
|
26 |
|
$ret .= 'THEN ' . $component->results[$i] . ' '; |
272
|
|
|
} |
273
|
|
|
} else { |
274
|
|
|
// Syntax type 1 |
275
|
30 |
|
$valuesCount = count($component->conditions); |
276
|
30 |
|
$resultsCount = count($component->results); |
277
|
30 |
|
for ($i = 0; $i < $valuesCount && $i < $resultsCount; ++$i) { |
278
|
28 |
|
$ret .= 'WHEN ' . Condition::build($component->conditions[$i]) . ' '; |
279
|
28 |
|
$ret .= 'THEN ' . $component->results[$i] . ' '; |
280
|
|
|
} |
281
|
|
|
} |
282
|
|
|
|
283
|
56 |
|
if (isset($component->elseResult)) { |
284
|
32 |
|
$ret .= 'ELSE ' . $component->elseResult . ' '; |
285
|
|
|
} |
286
|
|
|
|
287
|
56 |
|
$ret .= 'END'; |
288
|
|
|
|
289
|
56 |
|
if ($component->alias) { |
290
|
20 |
|
$ret .= ' AS ' . Context::escape($component->alias); |
291
|
|
|
} |
292
|
|
|
|
293
|
56 |
|
return $ret; |
294
|
|
|
} |
295
|
|
|
|
296
|
|
|
public function __toString(): string |
297
|
|
|
{ |
298
|
|
|
return static::build($this); |
299
|
|
|
} |
300
|
|
|
} |
301
|
|
|
|