<?php declare(strict_types=1);

/*
 * This file is part of the Rapsys PackBundle package.
 *
 * (c) Raphaël Gertz <symfony@rapsys.eu>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Rapsys\PackBundle\Parser;

use Symfony\Component\Asset\PackageInterface;
use Symfony\Component\Filesystem\Exception\IOExceptionInterface;
use Symfony\Component\Filesystem\Filesystem;
use Symfony\Component\HttpKernel\Config\FileLocator;

use Twig\Error\Error;
use Twig\Node\Expression\AssignNameExpression;
use Twig\Node\Node;
use Twig\Node\SetNode;
use Twig\Node\TextNode;
use Twig\Source;
use Twig\Token;
use Twig\TokenParser\AbstractTokenParser;

class TokenParser extends AbstractTokenParser {
	/**
	 * The stream context instance
	 */
	protected mixed $ctx;

	/**
	 * Constructor
	 *
	 * @param FileLocator $locator The FileLocator instance
	 * @param PackageInterface $package The Assets Package instance
	 * @param array $config The config path
	 * @param string $tag The tag name
	 * @param string $output The default output string
	 * @param array $filters The default filters array
	 */
	//TODO: change config to name and get other values from RAPSYSPACK_REDIRECT, RAPSYSPACK_SCHEME, RAPSYSPACK_TIMEOUT, RAPSYSPACK_AGENT env variables ?
	public function __construct(protected FileLocator $locator, protected PackageInterface $package, protected array $config, protected string $tag, protected string $output, protected array $filters) {
		//Set ctx
		$this->ctx = stream_context_create(
			[
				'http' => [
					#'header' => ['Referer: https://www.openstreetmap.org/'],
					//TODO: set as bundle env config
					'max_redirects' => $config['redirect']?:5,
					//TODO: set as bundle env config
					'timeout' => $config['timeout']?:(int)ini_get('default_socket_timeout'),
					#'user_agent' => 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.63 Safari/537.36',
					//TODO: set as bundle env config
					'user_agent' => $config['agent']?:(string)ini_get('user_agent')?:'rapsys_pack/2.0.0',
				]
			]
		);
	}

	/**
	 * Get the tag name
	 *
	 * @return string This tag name
	 */
	public function getTag(): string {
		return $this->tag;
	}

	/**
	 * Parse the token
	 *
	 * @xxx Skip filter when debug mode is enabled is not possible
	 * @xxx This code is only run once when twig cache is enabled
	 * @xxx Twig cache value is not avaible in container parameters, maybe in twig env ?
	 *
	 * @param Token $token The \Twig\Token instance
	 * @return Node The PackNode
	 */
	public function parse(Token $token): Node {
		$parser = $this->parser;
		$stream = $this->parser->getStream();

		$inputs = [];
		$name = $this->config['name'];
		$output = $this->output;
		$filters = $this->filters;

		$content = '';

		//Process the token block until end
		while (!$stream->test(Token::BLOCK_END_TYPE)) {
			//The files to process
			if ($stream->test(Token::STRING_TYPE)) {
				//'somewhere/somefile.(css,img,js)' 'somewhere/*' '@jquery'
				$inputs[] = $stream->next()->getValue();
			//The filters token
			} elseif ($stream->test(Token::NAME_TYPE, 'filters')) {
				//filter='yui_js'
				$stream->next();
				$stream->expect(Token::OPERATOR_TYPE, '=');
				$filters = array_merge($filters, array_filter(array_map('trim', explode(',', $stream->expect(Token::STRING_TYPE)->getValue()))));
			//The output token
			} elseif ($stream->test(Token::NAME_TYPE, 'output')) {
				//output='js/packed/*.js' OR output='js/core.js'
				$stream->next();
				$stream->expect(Token::OPERATOR_TYPE, '=');
				$output = $stream->expect(Token::STRING_TYPE)->getValue();
			//The name token
			} elseif ($stream->test(Token::NAME_TYPE, 'name')) {
				//name='core_js'
				$stream->next();
				$stream->expect(Token::OPERATOR_TYPE, '=');
				$name = $stream->expect(Token::STRING_TYPE)->getValue();
			//Unexpected token
			} else {
				$token = $stream->getCurrent();
				throw new Error(sprintf('Unexpected token "%s" of value "%s"', Token::typeToEnglish($token->getType()), $token->getValue()), $token->getLine(), $stream->getSourceContext());
			}
		}

		//Process end block
		$stream->expect(Token::BLOCK_END_TYPE);

		//Process body
		$body = $this->parser->subparse([$this, 'testEndTag'], true);

		//Process end block
		$stream->expect(Token::BLOCK_END_TYPE);

		//Replace star with sha1
		if (($pos = strpos($output, '*')) !== false) {
			//XXX: assetic use substr(sha1(serialize($inputs).serialize($filters).serialize($options)), 0, 7)
			$output = substr($output, 0, $pos).sha1(serialize($inputs).serialize($filters)).substr($output, $pos + 1);
		}

		//Process inputs
		for($k = 0; $k < count($inputs); $k++) {
			//Deal with generic url
			if (strpos($inputs[$k], '//') === 0) {
				//Fix url
				//TODO: set as bundle env config
				$inputs[$k] = $this->config['scheme'].substr($inputs[$k], 2);
			//Deal with non url path
			} elseif (strpos($inputs[$k], '://') === false) {
				//Check if we have a bundle path
				if ($inputs[$k][0] == '@') {
					//Resolve it
					$inputs[$k] = $this->getLocated($inputs[$k], $token->getLine(), $stream->getSourceContext());
				}

				//Deal with globs
				if (strpos($inputs[$k], '*') !== false || (($a = strpos($inputs[$k], '{')) !== false && ($b = strpos($inputs[$k], ',', $a)) !== false && strpos($inputs[$k], '}', $b) !== false)) {
					//Get replacement
					$replacement = glob($inputs[$k], GLOB_NOSORT|GLOB_BRACE);
					//Check that these are working files
					foreach($replacement as $input) {
						//Check that it's a file
						if (!is_file($input)) {
							throw new Error(sprintf('Input path "%s" from "%s" is not a file', $input, $inputs[$k]), $token->getLine(), $stream->getSourceContext());
						}
					}
					//Replace with glob path
					array_splice($inputs, $k, 1, $replacement);
					//Fix current key
					$k += count($replacement) - 1;
				//Check that it's a file
				} elseif (!is_file($inputs[$k])) {
					throw new Error(sprintf('Input path "%s" is not a file', $inputs[$k]), $token->getLine(), $stream->getSourceContext());
				}
			}
		}

		//Check inputs
		if (!empty($inputs)) {
			//Retrieve files content
			foreach($inputs as $input) {
				//Try to retrieve content
				if (($data = file_get_contents($input, false, $this->ctx)) === false) {
					throw new Error(sprintf('Unable to retrieve input path "%s"', $input), $token->getLine(), $stream->getSourceContext());
				}
				//Append content
				$content .= $data;
			}
		} else {
			//Trigger error about empty inputs ?
			//XXX: There may be a legitimate case where we want an empty file or an error, feel free to contact the author in such case
			#throw new Error('Empty inputs token', $token->getLine(), $stream->getSourceContext());

			//Send an empty node without inputs
			return new Node();
		}

		//Check filters
		if (!empty($filters)) {
			//Apply all filters
			foreach($filters as $filter) {
				//Init args
				$args = [$stream->getSourceContext(), $token->getLine()];
				//Check if args is available
				if (!empty($filter['args'])) {
					//Append args if provided
					$args += $filter['args'];
				}
				//Init reflection
				$reflection = new \ReflectionClass($filter['class']);
				//Set instance args
				$tool = $reflection->newInstanceArgs($args);
				//Process content
				$content = $tool->process($content);
				//Remove object
				unset($tool, $reflection);
			}
		} else {
			//Trigger error about empty filters ?
			//XXX: There may be a legitimate case where we want only a merged file or an error, feel free to contact the author in such case
			#throw new Error('Empty filters token', $token->getLine(), $stream->getSourceContext());
		}

		//Retrieve asset uri
		//XXX: this path is the merge of services.assets.path_package.arguments[0] and rapsys_pack.output.(css,img,js)
		if (($outputUrl = $this->package->getUrl($output)) === false) {
			throw new Error(sprintf('Unable to get url for asset: %s', $output), $token->getLine(), $stream->getSourceContext());
		}

		//Check if we have a bundle path
		if ($output[0] == '@') {
			//Resolve it
			$output = $this->getLocated($output, $token->getLine(), $stream->getSourceContext());
		}

		//Get filesystem
		$filesystem = new Filesystem();

		//Create output dir if not present
		if (!is_dir($dir = dirname($output))) {
			try {
				//Create dir
				//XXX: set as 0775, symfony umask (0022) will reduce rights (0755)
				$filesystem->mkdir($dir, 0775);
			} catch (IOExceptionInterface $e) {
				//Throw error
				throw new Error(sprintf('Output directory "%s" do not exists and unable to create it', $dir), $token->getLine(), $stream->getSourceContext(), $e);
			}
		}

		//Send file content
		try {
			//Write content to file
			//XXX: this call is (maybe) atomic
			//XXX: see https://symfony.com/doc/current/components/filesystem.html#dumpfile
			$filesystem->dumpFile($output, $content);
		} catch (IOExceptionInterface $e) {
			//Throw error
			throw new Error(sprintf('Unable to write to: %s', $output), $token->getLine(), $stream->getSourceContext(), $e);
		}

		//Set name in context key
		$ref = new AssignNameExpression($name, $token->getLine());

		//Set output in context value
		$value = new TextNode($outputUrl, $token->getLine());

		//Send body with context set
		return new Node([
			//This define name in twig template by prepending $context['<name>'] = '<output>';
			new SetNode(true, $ref, $value, $token->getLine(), $this->getTag()),
			//The tag captured body
			$body
		]);
	}

	/**
	 * Test for tag end
	 *
	 * @param Token $token The \Twig\Token instance
	 * @return bool The token end test result
	 */
	public function testEndTag(Token $token): bool {
		return $token->test(['end'.$this->getTag()]);
	}

	/**
	 * Get path from bundled file
	 *
	 * @see https://symfony.com/doc/current/bundles.html#overridding-the-bundle-directory-structure
	 *
	 * @param string $file The bundled file path
	 * @param int $lineno The template line where the error occurred
	 * @param Source $source The source context where the error occurred
	 * @param Exception $prev The previous exception
	 * @return string The resolved file path
	 */
	public function getLocated(string $file, int $lineno = 0, ?Source $source = null, ?\Exception $prev = null): string {
		/*TODO: add a @jquery magic feature ?
		if ($file == '@jquery') {
			#header('Content-Type: text/plain');
			#var_dump($inputs);
			#exit;
			return $this->config['jquery'];
		}*/

		//Check that we have a / separator between bundle name and path
		if (($pos = strpos($file, '/')) === false) {
			throw new Error(sprintf('Invalid path "%s"', $file), $lineno, $source);
		}

		//Set bundle
		$bundle = substr($file, 0, $pos);

		//Set path
		$path = substr($file, $pos + 1);

		//Check for bundle suffix presence
		//XXX: use "bundle templates automatic namespace" mimicked behaviour to find intended bundle and/or path
		//XXX: see https://symfony.com/doc/4.3/templates.html#bundle-templates
		if (strlen($bundle) < strlen('Bundle') || substr($bundle, -strlen('Bundle')) !== 'Bundle') {
			//Append Bundle in an attempt to fix it's naming for locator
			$bundle .= 'Bundle';

			//Check for public resource prefix presence
			if (strlen($path) < strlen('Resources/public') || substr($path, 0, strlen('Resources/public')) != 'Resources/public') {
				//Prepend standard public path
				$path = 'Resources/public/'.$path;
			}
		}

		//Resolve bundle prefix
		try {
			$prefix = $this->locator->locate($bundle);
		//Catch bundle does not exist or is not enabled exception
		} catch(\InvalidArgumentException $e) {
			//Fix lowercase first bundle character
			if ($bundle[1] > 'Z' || $bundle[1] < 'A') {
				$bundle[1] = strtoupper($bundle[1]);
			}

			//Detect double bundle suffix
			if (strlen($bundle) > strlen('_bundleBundle') && substr($bundle, -strlen('_bundleBundle')) == '_bundleBundle') {
				//Strip extra bundle
				$bundle = substr($bundle, 0, -strlen('Bundle'));
			}

			//Convert snake case in camel case
			if (strpos($bundle, '_') !== false) {
				//Fix every first character following a _
				while(($cur = strpos($bundle, '_')) !== false) {
					$bundle = substr($bundle, 0, $cur).ucfirst(substr($bundle, $cur + 1));
				}
			}

			//Resolve fixed bundle prefix
			try {
				$prefix = $this->locator->locate($bundle);
				//Catch bundle does not exist or is not enabled exception again
			} catch(\InvalidArgumentException $e) {
				//Bail out as bundle or path is invalid and we have no way to know what was meant
				throw new Error(sprintf('Invalid bundle name "%s" in path "%s". Maybe you meant "%s"', substr($file, 1, $pos - 1), $file, $bundle.'/'.$path), $lineno, $source, $e);
			}
		}

		//Return solved bundle prefix and path
		return $prefix.$path;
	}
}