Parsing parameter from string | regex | php - php

Question

I am having problems parsing parameter from a string.
Parameter are defined by the following:
can be written in short or long notation, p.ex:
-a / --long
characters range from [a-z0-9] for short and [a-z0-9\-] for long notation, p.ex:
--long-with-dash
can have a value, but don't have to, p.ex:
-a test / --aaaa
can have multiple arguments, without being in quotes, p.ex:
-a val1 val2
(that should be captures as one group: value = "val1 val2")
can have custom text inside quotes
--custom "here can stand everything, --test test :( "
parameter can have a "!" infront
! --test test / ! -a
values can have "-" inside
-a value-with-dash
All these Parameters come in one long string, p.ex:
-a val1 ! -b val2 --other "string with crazy -a --test stuff inside" --param-with-dash val1 val2 -test value-with-dash ! -c -d ! --test
-- EDIT ----
also --param value-with-dash
-- END EDIT ---
This is as close as i can get:
https://regex101.com/r/3aPHzp/1
/(?:(?P<inverted>\!) )?(?P<names>\-{1,2}\S+)($| (?P<values>.+(?=(?: [\!|\-])|$)))/U
unfortunatly it breaks when it comes to the free text value inside quotes. And when a parameter without value is followed by the next parameter.
(i try to parse the output of iptables-save, in case you are interessted. Also, maybe i split can split the string in an other fancy way before, to avoid a hugh regex, but i don't see it).
Thank you very much for your help!
-- FINAL SOLUTION --
for PHP >= 5.6
(?<inverted>!)?\s*(?<name>--?\w[\w-]*)\s*(?<values>(?:\s*(?:\w\S*|["'](?:[^"'\\]*(?:\\.[^"'\\]*)*)['"]))*)\K
Demo: https://regex101.com/r/xSfgxP/1
for PHP < 5.6
(?<inverted>\!)?\s*(?<=(?:\s)|^)(?<name>\-{1,2}\w[\w\-]*)\s+(?<value>(?:\s*(?:\w\S*|["'](?:[^"'\\]*(?:\\.[^"'\\]*)*)['"]))*)

Answer 1

RegEx:
(?<inverted>!)?\s*(?<name>--?\w[\w-]*)\s*(?<values>(?:\s*(?:\w\S+|["'](?:[^"'\\]*(?:\\.[^"'\\]*)*)['"]))*)\K
Live demo (updated)
Breakdown
(?<inverted> ! )? # (1) Named-capturing group for inverted result
\s* # Match any spaces
(?<name> --? \w [\w-]* ) # (2) Named-capturing group for parameter name
\s* # Match any spaces
(?<values> # (3 start) Named capturing group for values
(?: # Beginning of a non-capturing group (a)
\s* # Match any spaces
(?: # Beginning of a non-capturing group (b)
\w\S+ # Match a [a-zA-Z0-9_] character then any non-whitespace characters
| # Or
["'] # Match a qoutation mark
(?: # Beginning of a non-capturing group (c)
[^"'\\]* # Match anything except `"`, `'` or `\`
(?: \\ . [^"'\\]* )* # Match an escaped character then anyhthing except `"`, `'` or `\` as much as possible
) # End of non-capturing group (c)
['"] # Match qutation pair
) # End of non-capturing group (b)
)* # Greedy (a), end of non-capturing group (a)
) # (3 end)
\K # Reset allocated memory of all previously matched characters
PHP code:
<?php
$str = '-a val1 ! -b val2 --custom "string :)(#with crazy -a --test stuff inside" --param-with-dash val1 val2 -c ! -d ! --test';
$re = <<< 'RE'
~(?<inverted>!)?\s*(?<name>--?\w[\w-]*)\s*(?<values>(?:\s*(?:\w\S+|["'](?:[^"'\\]*(?:\\.[^"'\\]*)*)['"]))*)\K~
RE;
preg_match_all($re, $str, $matches, PREG_SET_ORDER);
print_r(array_map('array_filter', $matches));
Output:
Array
(
[0] => Array
(
[name] => -a
[2] => -a
[values] => val1
[3] => val1
)
[1] => Array
(
[inverted] => !
[1] => !
[name] => -b
[2] => -b
[values] => val2
[3] => val2
)
[2] => Array
(
[name] => --custom
[2] => --custom
[values] => "string :)(#with crazy -a --test stuff inside"
[3] => "string :)(#with crazy -a --test stuff inside"
)
[3] => Array
(
[name] => --param-with-dash
[2] => --param-with-dash
[values] => val1 val2
[3] => val1 val2
)
[4] => Array
(
[name] => -c
[2] => -c
)
[5] => Array
(
[inverted] => !
[1] => !
[name] => -d
[2] => -d
)
[6] => Array
(
[inverted] => !
[1] => !
[name] => --test
[2] => --test
)
)