Segment::buildRegex() - Code Metrics - DASPRiD/Dash - Measure and Improve Code Quality continuously with Scrutinizer

Segment::buildRegex() C
last analyzed 2016-02-10 03:22 UTC

↳ Parent: Segment

Complexity

Conditions	8
Paths	8

Size

Total Lines	39
Code Lines	27

Duplication

Lines	0
Ratio	0 %

Importance

Changes	2
Bugs	1	Features	0

Metric	Value
c	2
b	1
f	0
dl	0
loc	39
rs	5.3846
cc	8
eloc	27
nc	8
nop	2

<?php
/**
 * Dash
 *
 * @link      http://github.com/DASPRiD/Dash For the canonical source repository
 * @copyright 2013-2015 Ben Scholzen 'DASPRiD'
 * @license   http://opensource.org/licenses/BSD-2-Clause Simplified BSD License
 */

namespace Dash\Parser;

use Dash\Exception;

class Segment implements ParserInterface
{
    /**#@+
     * Descriptive part elements.
     */
    const TYPE       = 0;
    const NAME       = 1;
    const LITERAL    = 1;
    const DELIMITERS = 2;
    /**#@-*/

    /**
     * @var string
     */
    protected $delimiter;

    /**
     * @var string
     */
    protected $pattern;

    /**
     * @var array
     */
    protected $constraints;

    /**
     * @var array
     */
    protected $tokens;

    /**
     * @var string
     */
    protected $regex;

    /**
     * @var array
     */
    protected $paramMap = [];

    /**
     * @param string $delimiter
     * @param string $pattern
     * @param array  $constraints
     */
    public function __construct($delimiter, $pattern, array $constraints)
    {
        $this->delimiter   = $delimiter;
        $this->pattern     = $pattern;
        $this->constraints = $constraints;
    }

    /**
     * {@inheritdoc}
     */
    public function parse($input, $offset)
    {
        $result = preg_match('(\G' . $this->getRegex() . ')', $input, $matches, null, $offset);

        if (!$result) {
            return null;
        }

        $params = [];

        foreach ($this->paramMap as $index => $name) {
            if (isset($matches[$index]) && $matches[$index] !== '') {
                $params[$name] = $matches[$index];
            }
        }

        return new ParseResult($params, strlen($matches[0]));
    }

    /**
     * {@inheritdoc}
     */
    public function compile(array $params, array $defaults)
    {
        return $this->buildString(
            $this->getTokens(),
            array_merge($defaults, $params),
            $defaults
        );
    }

    /**
     * Gets regex for matching.
     *
     * @return string
     */
    protected function getRegex()
    {
        if ($this->regex === null) {
            $this->regex = $this->buildRegex($this->getTokens(), $this->constraints);
        }

        return $this->regex;
    }

    /**
     * Gets parsed tokens.
     *
     * @return array
     */
    protected function getTokens()
    {
        if ($this->tokens === null) {
            $this->tokens = $this->parsePattern($this->pattern);
        }

        return $this->tokens;
    }

    /**
     * Parses a pattern.
     *
     * @param  string $pattern
     * @return array
     * @throws Exception\RuntimeException
     */
    protected function parsePattern($pattern)
    {
        $currentPos      = 0;
        $length          = strlen($pattern);
        $tokens          = [];
        $level           = 0;
        $quotedDelimiter = preg_quote($this->delimiter);

        while ($currentPos < $length) {
            preg_match('(\G(?P<literal>[^:{\[\]]*)(?P<token>[:\[\]]|$))', $pattern, $matches, 0, $currentPos);

            $currentPos += strlen($matches[0]);

            if (!empty($matches['literal'])) {
                $tokens[] = ['literal', $matches['literal']];
            }

            if ($matches['token'] === ':') {
                if (!preg_match(
                    '(\G(?P<name>[^:' . $quotedDelimiter . '{\[\]]+)(?:{(?P<delimiters>[^}]+)})?:?)',
                    $pattern,
                    $matches,
                    0,
                    $currentPos
                )) {
                    throw new Exception\RuntimeException('Found empty parameter name');
                }

                $tokens[] = [
                    'parameter',
                    $matches['name'],
                    isset($matches['delimiters']) ? $matches['delimiters'] : null
                ];

                $currentPos += strlen($matches[0]);
            } elseif ($matches['token'] === '[') {
                $tokens[] = ['optional-start'];
                $level++;
            } elseif ($matches['token'] === ']') {
                $tokens[] = ['optional-end'];
                $level--;

                if ($level < 0) {
                    throw new Exception\RuntimeException('Found closing bracket without matching opening bracket');
                }
            } else {
                break;
            }
        }

        if ($level > 0) {
            throw new Exception\RuntimeException('Found unbalanced brackets');
        }

        return $tokens;
    }

    /**
     * Builds the matching regex from parsed tokens.
     *
     * @param  array $tokens
     * @param  array $constraints
     * @return string
     */
    protected function buildRegex(array $tokens, array $constraints)
    {
        $groupIndex      = 1;
        $regex           = '';
        $quotedDelimiter = preg_quote($this->delimiter);

        foreach ($tokens as $token) {
            switch ($token[static::TYPE]) {
                case 'literal':
                    $regex .= preg_quote($token[static::LITERAL]);
                    break;

                case 'parameter':
                    $groupName = '?P<param' . $groupIndex . '>';

                    if (isset($constraints[$token[static::NAME]])) {
                        $regex .= '(' . $groupName . $constraints[$token[static::NAME]] . ')';
                    } elseif ($token[static::DELIMITERS] === null) {
                        $regex .= '(' . $groupName . '[^' . $quotedDelimiter . ']+)';
                    } else {
                        $regex .= '(' . $groupName . '[^' . $token[static::DELIMITERS] . ']+)';
                    }

                    $this->paramMap['param' . $groupIndex] = $token[static::NAME];
                    ++$groupIndex;
                    break;

                case 'optional-start':
                    $regex .= '(?:';
                    break;

                case 'optional-end':
                    $regex .= ')?';
                    break;
            }
        }

        return $regex;
    }

    /**
     * Builds a string from parts.
     *
     * @param  array $parts
     * @param  array $mergedParams
     * @param  array $defaults
     * @return string
     * @throws Exception\InvalidArgumentException
     */
    protected function buildString(array $parts, array $mergedParams, array $defaults)
    {
        $stack   = [];
        $current = [
            'is_optional' => false,
            'skip'        => true,
            'skippable'   => false,
            'path'        => '',
        ];

        foreach ($parts as $part) {
            switch ($part[static::TYPE]) {
                case 'literal':
                    $current['path'] .= $part[static::LITERAL];
                    break;

                case 'parameter':
                    $current['skippable'] = true;

                    if (!isset($mergedParams[$part[static::NAME]])) {
                        if (!$current['is_optional']) {
                            throw new Exception\InvalidArgumentException(sprintf(
                                'Missing parameter "%s"',
                                $part[static::NAME]
                            ));
                        }

                        continue;
                    } elseif (!$current['is_optional']
                        || !isset($defaults[$part[static::NAME]])
                        || $defaults[$part[static::NAME]] !== $mergedParams[$part[static::NAME]]
                    ) {
                        $current['skip'] = false;
                    }

                    $current['path'] .= $mergedParams[$part[static::NAME]];
                    break;

                case 'optional-start':
                    $stack[] = $current;
                    $current = [
                        'is_optional' => true,
                        'skip'        => true,
                        'skippable'   => false,
                        'path'        => '',
                    ];
                    break;

                case 'optional-end':
                    $parent = array_pop($stack);

                    if (!($current['path'] !== ''
                        && $current['is_optional']
                        && $current['skippable']
                        && $current['skip'])
                    ) {
                        $parent['path'] .= $current['path'];
                        $parent['skip'] = false;
                    }

                    $current = $parent;
                    break;
            }
        }

        return $current['path'];
    }
}


1			<?php
2			/**
3			* Dash
4			*
5			* @link http://github.com/DASPRiD/Dash For the canonical source repository
6			* @copyright 2013-2015 Ben Scholzen 'DASPRiD'
7			* @license http://opensource.org/licenses/BSD-2-Clause Simplified BSD License
8			*/
9
10			namespace Dash\Parser;
11
12			use Dash\Exception;
13
14			class Segment implements ParserInterface
15			{
16			/**#@+
17			* Descriptive part elements.
18			*/
19			const TYPE = 0;
20			const NAME = 1;
21			const LITERAL = 1;
22			const DELIMITERS = 2;
23			/*#@-/
24
25			/**
26			* @var string
27			*/
28			protected $delimiter;
29
30			/**
31			* @var string
32			*/
33			protected $pattern;
34
35			/**
36			* @var array
37			*/
38			protected $constraints;
39
40			/**
41			* @var array
42			*/
43			protected $tokens;
44
45			/**
46			* @var string
47			*/
48			protected $regex;
49
50			/**
51			* @var array
52			*/
53			protected $paramMap = [];
54
55			/**
56			* @param string $delimiter
57			* @param string $pattern
58			* @param array $constraints
59			*/
60			public function __construct($delimiter, $pattern, array $constraints)
61			{
62			$this->delimiter = $delimiter;
63			$this->pattern = $pattern;
64			$this->constraints = $constraints;
65			}
66
67			/**
68			* {@inheritdoc}
69			*/
70			public function parse($input, $offset)
71			{
72			$result = preg_match('(\G' . $this->getRegex() . ')', $input, $matches, null, $offset);
73
74			if (!$result) {
75			return null;
76			}
77
78			$params = [];
79
80			foreach ($this->paramMap as $index => $name) {
81			if (isset($matches[$index]) && $matches[$index] !== '') {
82			$params[$name] = $matches[$index];
83			}
84			}
85
86			return new ParseResult($params, strlen($matches[0]));
87			}
88
89			/**
90			* {@inheritdoc}
91			*/
92			public function compile(array $params, array $defaults)
93			{
94			return $this->buildString(
95			$this->getTokens(),
96			array_merge($defaults, $params),
97			$defaults
98			);
99			}
100
101			/**
102			* Gets regex for matching.
103			*
104			* @return string
105			*/
106			protected function getRegex()
107			{
108			if ($this->regex === null) {
109			$this->regex = $this->buildRegex($this->getTokens(), $this->constraints);
110			}
111
112			return $this->regex;
113			}
114
115			/**
116			* Gets parsed tokens.
117			*
118			* @return array
119			*/
120			protected function getTokens()
121			{
122			if ($this->tokens === null) {
123			$this->tokens = $this->parsePattern($this->pattern);
124			}
125
126			return $this->tokens;
127			}
128
129			/**
130			* Parses a pattern.
131			*
132			* @param string $pattern
133			* @return array
134			* @throws Exception\RuntimeException
135			*/
136			protected function parsePattern($pattern)
137			{
138			$currentPos = 0;
139			$length = strlen($pattern);
140			$tokens = [];
141			$level = 0;
142			$quotedDelimiter = preg_quote($this->delimiter);
143
144			while ($currentPos < $length) {
145			preg_match('(\G(?P<literal>[^:{\[\]]*)(?P<token>[:\[\]]\|$))', $pattern, $matches, 0, $currentPos);
146
147			$currentPos += strlen($matches[0]);
148
149			if (!empty($matches['literal'])) {
150			$tokens[] = ['literal', $matches['literal']];
151			}
152
153			if ($matches['token'] === ':') {
154			if (!preg_match(
155			'(\G(?P<name>[^:' . $quotedDelimiter . '{\[\]]+)(?:{(?P<delimiters>[^}]+)})?:?)',
156			$pattern,
157			$matches,
158			0,
159			$currentPos
160			)) {
161			throw new Exception\RuntimeException('Found empty parameter name');
162			}
163
164			$tokens[] = [
165			'parameter',
166			$matches['name'],
167			isset($matches['delimiters']) ? $matches['delimiters'] : null
168			];
169
170			$currentPos += strlen($matches[0]);
171			} elseif ($matches['token'] === '[') {
172			$tokens[] = ['optional-start'];
173			$level++;
174			} elseif ($matches['token'] === ']') {
175			$tokens[] = ['optional-end'];
176			$level--;
177
178			if ($level < 0) {
179			throw new Exception\RuntimeException('Found closing bracket without matching opening bracket');
180			}
181			} else {
182			break;
183			}
184			}
185
186			if ($level > 0) {
187			throw new Exception\RuntimeException('Found unbalanced brackets');
188			}
189
190			return $tokens;
191			}
192
193			/**
194			* Builds the matching regex from parsed tokens.
195			*
196			* @param array $tokens
197			* @param array $constraints
198			* @return string
199			*/
200			protected function buildRegex(array $tokens, array $constraints)
201			{
202			$groupIndex = 1;
203			$regex = '';
204			$quotedDelimiter = preg_quote($this->delimiter);
205
206			foreach ($tokens as $token) {
207			switch ($token[static::TYPE]) {
208			case 'literal':
209			$regex .= preg_quote($token[static::LITERAL]);
210			break;
211
212			case 'parameter':
213			$groupName = '?P<param' . $groupIndex . '>';
214
215			if (isset($constraints[$token[static::NAME]])) {
216			$regex .= '(' . $groupName . $constraints[$token[static::NAME]] . ')';
217			} elseif ($token[static::DELIMITERS] === null) {
218			$regex .= '(' . $groupName . '[^' . $quotedDelimiter . ']+)';
219			} else {
220			$regex .= '(' . $groupName . '[^' . $token[static::DELIMITERS] . ']+)';
221			}
222
223			$this->paramMap['param' . $groupIndex] = $token[static::NAME];
224			++$groupIndex;
225			break;
226
227			case 'optional-start':
228			$regex .= '(?:';
229			break;
230
231			case 'optional-end':
232			$regex .= ')?';
233			break;
234			}
235			}
236
237			return $regex;
238			}
239
240			/**
241			* Builds a string from parts.
242			*
243			* @param array $parts
244			* @param array $mergedParams
245			* @param array $defaults
246			* @return string
247			* @throws Exception\InvalidArgumentException
248			*/
249			protected function buildString(array $parts, array $mergedParams, array $defaults)
250			{
251			$stack = [];
252			$current = [
253			'is_optional' => false,
254			'skip' => true,
255			'skippable' => false,
256			'path' => '',
257			];
258
259			foreach ($parts as $part) {
260			switch ($part[static::TYPE]) {
261			case 'literal':
262			$current['path'] .= $part[static::LITERAL];
263			break;
264
265			case 'parameter':
266			$current['skippable'] = true;
267
268			if (!isset($mergedParams[$part[static::NAME]])) {
269			if (!$current['is_optional']) {
270			throw new Exception\InvalidArgumentException(sprintf(
271			'Missing parameter "%s"',
272			$part[static::NAME]
273			));
274			}
275
276			continue;
277			} elseif (!$current['is_optional']
278			\|\| !isset($defaults[$part[static::NAME]])
279			\|\| $defaults[$part[static::NAME]] !== $mergedParams[$part[static::NAME]]
280			) {
281			$current['skip'] = false;
282			}
283
284			$current['path'] .= $mergedParams[$part[static::NAME]];
285			break;
286
287			case 'optional-start':
288			$stack[] = $current;
289			$current = [
290			'is_optional' => true,
291			'skip' => true,
292			'skippable' => false,
293			'path' => '',
294			];
295			break;
296
297			case 'optional-end':
298			$parent = array_pop($stack);
299
300			if (!($current['path'] !== ''
301			&& $current['is_optional']
302			&& $current['skippable']
303			&& $current['skip'])
304			) {
305			$parent['path'] .= $current['path'];
306			$parent['skip'] = false;
307			}
308
309			$current = $parent;
310			break;
311			}
312			}
313
314			return $current['path'];
315			}
316			}
317

DASPRiD / Dash

Segment::buildRegex() C last analyzed 2016-02-10 03:22 UTC

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like

Segment::buildRegex() C
last analyzed 2016-02-10 03:22 UTC