<?php

declare(strict_types=1);

namespace CodeIgniter\Settings;

use CodeIgniter\Config\BaseConfig;

use CodeIgniter\Settings\Config\Settings as SettingsConfig;

use CodeIgniter\Settings\Handlers\BaseHandler;

use InvalidArgumentException;

use RuntimeException;

/**

* Allows developers a single location to store and

* retrieve settings that were original set in config files

* in the core application or any third-party module.

*/

class Settings

{

/**

* An array of handlers for getting/setting the values.

*

* @var list<BaseHandler>

*/

private array $handlers = [];

/**

* An array of the config options for each handler.

*

* @var array<string,array<string,mixed>>

*/

private ?array $options = null;

/**

* Grabs instances of our handlers.

*/

public function __construct(SettingsConfig $config)

{

foreach ($config->handlers as $handler) {

$class = $config->{$handler}['class'] ?? null;

if ($class === null) {

continue;

}

$this->handlers[$handler] = new $class();

$this->options[$handler] = $config->{$handler};

}

}

/**

* Retrieve a value from any handler

* or from a config file matching the name

* file.arg.optionalArg

*/

public function get(string $key, ?string $context = null)

{

[$class, $property, $config] = $this->prepareClassAndProperty($key);

// Check each of our handlers

foreach ($this->handlers as $handler) {

if ($handler->has($class, $property, $context)) {

return $handler->get($class, $property, $context);

}

}

// If no contextual value was found then fall back to general

if ($context !== null) {

return $this->get($key);

}

return $config->{$property} ?? null;

}

/**

* Save a value to the writable handler for later retrieval.

*

* @param mixed $value

*/

public function set(string $key, $value = null, ?string $context = null): void

{

[$class, $property] = $this->prepareClassAndProperty($key);

foreach ($this->getWriteHandlers() as $handler) {

$handler->set($class, $property, $value, $context);

}

}

/**

* Removes a setting from the persistent storage,

* effectively returning the value to the default value

* found in the config file, if any.

*/

public function forget(string $key, ?string $context = null): void

{

[$class, $property] = $this->prepareClassAndProperty($key);

foreach ($this->getWriteHandlers() as $handler) {

$handler->forget($class, $property, $context);

}

}

/**

* Removes all settings from the persistent storage,

* Useful during testing. Use with caution.

*/

public function flush(): void

{

foreach ($this->getWriteHandlers() as $handler) {

$handler->flush();

}

}

/**

* Returns the handler that is set to store values.

*

* @return list<BaseHandler>

*

* @throws RuntimeException

*/

private function getWriteHandlers()

{

$handlers = [];

foreach ($this->options as $handler => $options) {

if (! empty($options['writeable'])) {

$handlers[] = $this->handlers[$handler];

}

}

if ($handlers === []) {

throw new RuntimeException('Unable to find a Settings handler that can store values.');

}

return $handlers;

}

/**

* Analyzes the given key and breaks it into the class.field parts.

*

* @return list<string>

*

* @throws InvalidArgumentException

*/

private function parseDotSyntax(string $key): array

{

// Parse the field name for class.field

$parts = explode('.', $key);

if (count($parts) === 1) {

throw new InvalidArgumentException('$key must contain both the class and field name, i.e. Foo.bar');

}

return $parts;

}

/**

* Given a key in class.property syntax, will split the values

* and determine the fully qualified class name, if possible.

*

* @return array{string, string, BaseConfig|null}

*/

private function prepareClassAndProperty(string $key): array

{

[$class, $property] = $this->parseDotSyntax($key);

$config = config($class);

// Use a fully qualified class name if the

// config file was found.

if ($config !== null) {

$class = $config::class;

}

return [$class, $property, $config];

}

}