rosavox/lib/alveolata/args/functions.php

<?php

namespace alveolata\args;

require_once(DIR_ALVEOLATA . '/log/functions.php');


/**
 * @param string $pattern
 * @param string $subject
 * @return array|null
 * @author Christian Fraß <frass@greenscale.de>
 */
function _regexp_match(
	string $pattern,
	string $subject
)
{
	$matches = [];
	$pattern_ = sprintf('/%s/', $pattern);
	$result = preg_match($pattern_, $subject, $matches);
	if ($result === 0) {
		return null;
	}
	else {
		return array_slice($matches, 1);
	}
}


/**
 * @param list<§x> $list
 * @param function<§x,§y> $function
 * @return list<§y>
 */
function _list_map(
	array $list,
	\Closure $function
) : array
{
	$list_ = [];
	for ($index = 0; $index < count($list); $index += 1) {
		$value = $list[$index];
		$value_ = $function($value, $index);
		array_push($list_, $value_);
	}
	return $list_;
}


/**
 * @param map<string,§x> $map
 * @param function<§x,§y> $function
 * @return map<string,§y>
 */
function _map_map(
	array $map,
	\Closure $function
) : array
{
	$map_ = [];
	foreach ($map as $key => $value) {
		$key_ = $key;
		$value_ = $function($value, $key);
		$map_[$key_] = $value_;
	}
	return $map_;
}


/**
 * @param record<positioned:list<record<target:string,?default:any,?processing:function<string,any>>>,named:map<string,record<target:string,?default:any,?processing:function<string,any>>>> $spec_raw
 * @param list<string> $args_raw
 * @return map<string,any>
 * @author Christian Fraß <frass@greenscale.de>
 */
function parse(
	array $spec_raw,
	array $args_raw,
	array $settings_given = []
) : array
{
	$settings_default = [
		'supress_warnings' => false,
	];
	$settings = array_merge(
		$settings_default,
		$settings_given
	);
	// spec refinement
	{
		$spec = [
			'positioned_mandatory' => _list_map(
				$spec_raw['positioned_mandatory'],
				function ($entry_raw, $index) {
					return [
						'target' => (
							array_key_exists('target', $entry_raw)
							? $entry_raw['target']
							: sprintf('_arg_%d', $index)
						),
						'processing' => (
							array_key_exists('processing', $entry_raw)
							? $entry_raw['processing']
							: (function ($value_raw) {return $value_raw;})
						),
					];
				}
			),
			'positioned_optional' => _list_map(
				$spec_raw['positioned_optional'],
				function ($entry_raw, $index) use (&$spec_raw) {
					return [
						'target' => (
							array_key_exists('target', $entry_raw)
							? $entry_raw['target']
							: sprintf('_arg_%d', $index + count($spec_raw['positioned_mandatory']))
						),
						'processing' => (
							array_key_exists('processing', $entry_raw)
							? $entry_raw['processing']
							: (function ($value_raw) {return $value_raw;})
						),
						'default' => (
							array_key_exists('default', $entry_raw)
							? $entry_raw['default']
							: null
						),
					];
				}
			),
			'named' => _map_map(
				$spec_raw['named'],
				function ($entry_raw, $key) {
					return [
						'target' => (
							array_key_exists('target', $entry_raw)
							? $entry_raw['target']
							: $key
						),
						'processing' => (
							array_key_exists('processing', $entry_raw)
							? $entry_raw['processing']
							: (function ($value_raw) {return $value_raw;})
						),
						'default' => (
							array_key_exists('default', $entry_raw)
							? $entry_raw['default']
							: null
						),
					];
				}
			),
		];
	}
	$args = [];
	// default values
	{
		foreach ($spec['positioned_optional'] as $entry) {
			$args[$entry['target']] = $entry['default'];
		}
		foreach ($spec['named'] as $entry) {
			$args[$entry['target']] = $entry['default'];
		}
	}
	// parsing
	{
		$position = 0;
		foreach ($args_raw as $arg_raw) {
			$result = _regexp_match('--([^=]+)=([^=]+)', $arg_raw);
			if ($result === null) {
				if ($position < count($spec['positioned_mandatory'])) {
					$entry = $spec['positioned_mandatory'][$position];
					$value_raw = $entry['processing']($arg_raw);
					$value = $value_raw;
					$args[$entry['target']] = $value;
				}
				else if ($position < count($spec['positioned_mandatory']) + count($spec['positioned_optional'])) {
					$entry = $spec['positioned_optional'][$position - count($spec['positioned_optional'])];
					$value_raw = $entry['processing']($arg_raw);
					$value = $value_raw;
					$args[$entry['target']] = $value;
				}
				else {
					if (! $settings['supress_warnings']) {
						\alveolata\log\warning(
							'unrecognized positional argument',
							[
								'position' => $position,
								'value' => $arg_raw,
							]
						);
					}
				}
				$position += 1;
			}
			else {
				$name = $result[0];
				$value_raw = $result[1];
				if (array_key_exists($name, $spec['named'])) {
					$entry = $spec['named'][$name];
					$value = $entry['processing']($value_raw);
					$args[$entry['target']] = $value;
				}
				else {
					if (! $settings['supress_warnings']) {
						\alveolata\log\warning(
							'unrecognized named argument',
							[
								'name' => $name,
								'value' => $value_raw,
							]
						);
					}
				}
			}
		}
		$left = array_slice($spec['positioned_mandatory'], $position);
		if (count($left) > 0) {
			throw (new \Exception(sprintf('%d missing mandatory positioned arguments', count($left))));
		}
	}
	return $args;
}