<?php

namespace Kirby\Panel;

use Kirby\Cms\App;
use Kirby\Exception\Exception;
use Kirby\Exception\InvalidArgumentException;
use Kirby\Filesystem\Asset;
use Kirby\Filesystem\Dir;
use Kirby\Filesystem\F;
use Kirby\Http\Response;
use Kirby\Http\Uri;
use Kirby\Toolkit\Tpl;
use Throwable;

/**
 * The Document is used by the View class to render
 * the full Panel HTML document in Fiber calls that
 * should not return just JSON objects
 * @since 3.6.0
 *
 * @package   Kirby Panel
 * @author    Bastian Allgeier <bastian@getkirby.com>
 * @link      https://getkirby.com
 * @copyright Bastian Allgeier
 * @license   https://getkirby.com/license
 */
class Document
{
	/**
	 * Generates an array with all assets
	 * that need to be loaded for the panel (js, css, icons)
	 */
	public static function assets(): array
	{
		$kirby = App::instance();
		$nonce = $kirby->nonce();

		// get the assets from the Vite dev server in dev mode;
		// dev mode = explicitly enabled in the config AND Vite is running
		$dev   = $kirby->option('panel.dev', false);
		$isDev = $dev !== false && is_file($kirby->roots()->panel() . '/.vite-running') === true;

		if ($isDev === true) {
			// vite on explicitly configured base URL or port 3000
			// of the current Kirby request
			if (is_string($dev) === true) {
				$url = $dev;
			} else {
				$url = rtrim($kirby->request()->url([
					'port'   => 3000,
					'path'   => null,
					'params' => null,
					'query'  => null
				])->toString(), '/');
			}
		} else {
			// vite is not running, use production assets
			$url = $kirby->url('media') . '/panel/' . $kirby->versionHash();
		}

		// fetch all plugins
		$plugins = new Plugins();

		$assets = [
			'css' => [
				'index'   => $url . '/css/style.css',
				'plugins' => $plugins->url('css'),
				'custom'  => static::customAsset('panel.css'),
			],
			'icons' => static::favicon($url),
			// loader for plugins' index.dev.mjs files – inlined, so we provide the code instead of the asset URL
			'plugin-imports' => $plugins->read('mjs'),
			'js' => [
				'vendor'       => [
					'nonce' => $nonce,
					'src'   => $url . '/js/vendor.js',
					'type'  => 'module'
				],
				'pluginloader' => [
					'nonce' => $nonce,
					'src'   => $url . '/js/plugins.js',
					'type'  => 'module'
				],
				'plugins'      => [
					'nonce' => $nonce,
					'src'   => $plugins->url('js'),
					'defer' => true
				],
				'custom'       => [
					'nonce' => $nonce,
					'src'   => static::customAsset('panel.js'),
					'type'  => 'module'
				],
				'index'        => [
					'nonce' => $nonce,
					'src'   => $url . '/js/index.js',
					'type'  => 'module'
				],
			]
		];

		// during dev mode, add vite client and adapt
		// path to `index.js` - vendor and stylesheet
		// don't need to be loaded in dev mode
		if ($isDev === true) {
			$assets['js']['vite']   = [
				'nonce' => $nonce,
				'src'   => $url . '/@vite/client',
				'type'  => 'module'
			];
			$assets['js']['index']  = [
				'nonce' => $nonce,
				'src'   => $url . '/src/index.js',
				'type'  => 'module'
			];

			unset($assets['css']['index'], $assets['js']['vendor']);
		}

		// remove missing files
		$assets['css'] = array_filter($assets['css']);
		$assets['js']  = array_filter(
			$assets['js'],
			fn ($js) => empty($js['src']) === false
		);

		return $assets;
	}

	/**
	 * Check for a custom asset file from the
	 * config (e.g. panel.css or panel.js)
	 * @since 3.7.0
	 *
	 * @param string $option asset option name
	 */
	public static function customAsset(string $option): string|null
	{
		if ($path = App::instance()->option($option)) {
			$asset = new Asset($path);

			if ($asset->exists() === true) {
				return $asset->url() . '?' . $asset->modified();
			}
		}

		return null;
	}

	/**
	 * Returns array of favicon icons
	 * based on config option
	 * @since 3.7.0
	 *
	 * @param string $url URL prefix for default icons
	 * @throws \Kirby\Exception\InvalidArgumentException
	 */
	public static function favicon(string $url = ''): array
	{
		$kirby = App::instance();
		$icons = $kirby->option('panel.favicon', [
			'apple-touch-icon' => [
				'type' => 'image/png',
				'url'  => $url . '/apple-touch-icon.png',
			],
			'alternate icon' => [
				'type' => 'image/png',
				'url'  => $url . '/favicon.png',
			],
			'shortcut icon' => [
				'type' => 'image/svg+xml',
				'url'  => $url . '/favicon.svg',
			]
		]);

		if (is_array($icons) === true) {
			return $icons;
		}

		// make sure to convert favicon string to array
		if (is_string($icons) === true) {
			return [
				'shortcut icon' => [
					'type' => F::mime($icons),
					'url'  => $icons,
				]
			];
		}

		throw new InvalidArgumentException('Invalid panel.favicon option');
	}

	/**
	 * Load the SVG icon sprite
	 * This will be injected in the
	 * initial HTML document for the Panel
	 */
	public static function icons(): string
	{
		$dev = App::instance()->option('panel.dev', false);
		$dir = $dev ? 'public' : 'dist';
		return F::read(App::instance()->root('kirby') . '/panel/' . $dir . '/img/icons.svg');
	}

	/**
	 * Links all dist files in the media folder
	 * and returns the link to the requested asset
	 *
	 * @throws \Kirby\Exception\Exception If Panel assets could not be moved to the public directory
	 */
	public static function link(): bool
	{
		$kirby       = App::instance();
		$mediaRoot   = $kirby->root('media') . '/panel';
		$panelRoot   = $kirby->root('panel') . '/dist';
		$versionHash = $kirby->versionHash();
		$versionRoot = $mediaRoot . '/' . $versionHash;

		// check if the version already exists
		if (is_dir($versionRoot) === true) {
			return false;
		}

		// delete the panel folder and all previous versions
		Dir::remove($mediaRoot);

		// recreate the panel folder
		Dir::make($mediaRoot, true);

		// copy assets to the dist folder
		if (Dir::copy($panelRoot, $versionRoot) !== true) {
			throw new Exception('Panel assets could not be linked');
		}

		return true;
	}

	/**
	 * Renders the panel document
	 */
	public static function response(array $fiber): Response
	{
		$kirby = App::instance();

		// Full HTML response
		// @codeCoverageIgnoreStart
		try {
			if (static::link() === true) {
				usleep(1);
				Response::go($kirby->url('base') . '/' . $kirby->path());
			}
		} catch (Throwable $e) {
			die('The Panel assets cannot be installed properly. ' . $e->getMessage());
		}
		// @codeCoverageIgnoreEnd

		// get the uri object for the panel url
		$uri = new Uri($url = $kirby->url('panel'));

		// proper response code
		$code = $fiber['$view']['code'] ?? 200;

		// load the main Panel view template
		$body = Tpl::load($kirby->root('kirby') . '/views/panel.php', [
			'assets'   => static::assets(),
			'icons'    => static::icons(),
			'nonce'    => $kirby->nonce(),
			'fiber'    => $fiber,
			'panelUrl' => $uri->path()->toString(true) . '/',
		]);

		return new Response($body, 'text/html', $code);
	}
}