<?php

namespace Kirby\Cms;

use Closure;
use Kirby\Exception\InvalidArgumentException;
use Kirby\Toolkit\Str;

/**
 * The `Helpers` class hosts a few handy helper methods
 * @since 3.7.0
 *
 * @package   Kirby Cms
 * @author    Nico Hoffmann <nico@getkirby.com>
 * @link      https://getkirby.com
 * @copyright Bastian Allgeier
 * @license   https://getkirby.com/license
 */
class Helpers
{
	/**
	 * Allows to disable specific deprecation warnings
	 * by setting them to `false`.
	 * You can do this by putting the following code in
	 * `site/config/config.php`:
	 *
	 * ```php
	 * Helpers::$deprecations['<deprecation-key>'] = false;
	 * ```
	 */
	public static $deprecations = [
		// The internal `$model->contentFile*()` methods have been deprecated
		'model-content-file' => true,

		// Passing an `info` array inside the `extends` array
		// has been deprecated. Pass the individual entries (e.g. root, version)
		// directly as named arguments.
		// TODO: switch to true in v6
		'plugin-extends-root' => false,

		// Passing a single space as value to `Xml::attr()` has been
		// deprecated. In a future version, passing a single space won't
		// render an empty value anymore but a single space.
		// To render an empty value, please pass an empty string.
		'xml-attr-single-space' => true,
	];

	/**
	 * Triggers a deprecation warning if debug mode is active
	 * and warning has not been surpressed via `Helpers::$deprecations`
	 *
	 * @param string|null $key If given, the key will be checked against the static array
	 * @return bool Whether the warning was triggered
	 */
	public static function deprecated(
		string $message,
		string|null $key = null
	): bool {
		// only trigger warning in debug mode or when running PHPUnit tests
		// @codeCoverageIgnoreStart
		if (
			App::instance()->option('debug') !== true &&
			(defined('KIRBY_TESTING') !== true || KIRBY_TESTING !== true)
		) {
			return false;
		}
		// @codeCoverageIgnoreEnd

		// don't trigger the warning if disabled by default or by the dev
		if ($key !== null && (static::$deprecations[$key] ?? true) === false) {
			return false;
		}

		return trigger_error($message, E_USER_DEPRECATED) === true;
	}

	/**
	 * Simple object and variable dumper
	 * to help with debugging.
	 */
	public static function dump(mixed $variable, bool $echo = true): string
	{
		$kirby  = App::instance();
		$output = print_r($variable, true);

		if ($kirby->environment()->cli() === true) {
			$output .= PHP_EOL;
		} else {
			$output = Str::wrap($output, '<pre>', '</pre>');
		}

		if ($echo === true) {
			echo $output;
		}

		return $output;
	}

	/**
	 * Performs an action with custom handling
	 * for all PHP errors and warnings
	 * @since 3.7.4
	 *
	 * @param \Closure $action Any action that may cause an error or warning
	 * @param \Closure $condition Closure that returns bool to determine if to
	 *                            suppress an error, receives arguments for
	 *                            `set_error_handler()`
	 * @param mixed $fallback Value to return when error is suppressed
	 * @return mixed Return value of the `$action` closure,
	 *               possibly overridden by `$fallback`
	 */
	public static function handleErrors(
		Closure $action,
		Closure $condition,
		$fallback = null
	) {
		$override = null;

		/**
		 * @psalm-suppress UndefinedVariable
		 */
		$handler = set_error_handler(function () use (&$override, &$handler, $condition, $fallback) {
			// check if suppress condition is met
			$suppress = $condition(...func_get_args());

			if ($suppress !== true) {
				// handle other warnings with Whoops if loaded
				if (is_callable($handler) === true) {
					return $handler(...func_get_args());
				}

				// otherwise use the standard error handler
				return false; // @codeCoverageIgnore
			}

			// use fallback to override return for suppressed errors
			$override = $fallback;

			if (is_callable($override) === true) {
				$override = $override();
			}

			// no additional error handling
			return true;
		});

		try {
			$result = $action();
		} finally {
			// always restore the error handler, even if the
			// action or the standard error handler threw an
			// exception; this avoids modifying global state
			restore_error_handler();
		}

		return $override ?? $result;
	}

	/**
	 * Checks if a helper was overridden by the user
	 * by setting the `KIRBY_HELPER_*` constant
	 * @internal
	 *
	 * @param string $name Name of the helper
	 */
	public static function hasOverride(string $name): bool
	{
		$name = 'KIRBY_HELPER_' . strtoupper($name);
		return defined($name) === true && constant($name) === false;
	}

	/**
	 * Determines the size/length of numbers,
	 * strings, arrays and countable objects
	 *
	 * @throws \Kirby\Exception\InvalidArgumentException
	 */
	public static function size(mixed $value): int
	{
		if (is_numeric($value)) {
			return (int)$value;
		}

		if (is_string($value)) {
			return Str::length(trim($value));
		}

		if (is_countable($value)) {
			return count($value);
		}

		throw new InvalidArgumentException('Could not determine the size of the given value');
	}
}