<?php

namespace Rapsys\PackBundle\Twig;

use Symfony\Component\HttpKernel\Config\FileLocator;
use Symfony\Component\Asset\PackageInterface;
use Twig\Error\Error;
use Twig\Node\Expression\AssignNameExpression;
use Twig\Node\Node;
use Twig\Node\SetNode;
use Twig\Node\TextNode;
use Twig\Token;
use Twig\TokenParser\AbstractTokenParser;

class PackTokenParser extends AbstractTokenParser {
	//The tag name
	private $tag;

	/**
	 * Constructor
	 *
	 * @param class		$locator	The FileLocator instance
	 * @param class		$package	The Assets Package instance
	 * @param string	$config		The config path
	 * @param string	$tag		The tag name
	 * @param string	$output		The default output string
	 * @param array		$filters	The default filters array
	 */
	public function __construct(FileLocator $locator, PackageInterface $package, $config, $tag, $output, $filters) {
		//Save locator
		$this->locator = $locator;

		//Save assets package
		$this->package = $package;

		//Set name
		$this->name = $config['name'];

		//Set scheme
		$this->scheme = $config['scheme'];

		//Set timeout
		$this->timeout = $config['timeout'];

		//Set agent
		$this->agent = $config['agent'];

		//Set redirect
		$this->redirect = $config['redirect'];

		//Set tag
		$this->tag = $tag;

		//Set output
		$this->output = $output;

		//Set filters
		$this->filters = $filters;
	}

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

	/**
	 * Parse the token
	 *
	 * @param class $token The \Twig\Token instance
	 *
	 * @return class The PackNode
	 *
	 * @todo see if we can't add a debug mode behaviour
	 *
	 * If twig.debug or env=dev (or rapsys_pack.config.debug?) is set, it should be possible to loop on each input
	 * and process the captured body without applying requested filter.
	 *
	 * @todo list:
	 * - detect debug mode
	 * - retrieve fixe link from input s%@(Name)Bundle/Resources/public(/somewhere/file.ext)%/bundles/\L\1\E\2%
	 * - for each inputs:
	 *   - generate a set asset_url=x
	 *   - generate a body
	 */
	public function parse(Token $token) {
		$parser = $this->parser;
		$stream = $this->parser->getStream();

		$inputs = [];
		$name = $this->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);

		//TODO: debug mode should be inserted here before the output variable is rewritten

		//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
				$inputs[$k] = $this->scheme.substr($inputs[$k], 2);
			//Deal with non url path
			} elseif (strpos($inputs[$k], '://') === false) {
				//Check if we have a bundle path
				if ($inputs[$k][0] == '@') {
					//Check that we have a / separator between bundle name and path
					if (($pos = strpos($inputs[$k], '/')) === false) {
						//TODO: add a @jquery magic feature ?
						/*
						header('Content-Type: text/plain');
						var_dump($inputs);
						if ($inputs[0] == '@jquery') {
							exit;
						}
						*/
						throw new Error(sprintf('Invalid input path "%s"', $inputs[$k]), $token->getLine(), $stream->getSourceContext());
					}
					//Resolve bundle prefix
					$inputs[$k] = $this->locator->locate(substr($inputs[$k], 0, $pos)).substr($inputs[$k], $pos + 1);
				}
				//Deal with globs
				if (strpos($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());
				}
			}
		}

		//Init context
		$ctx = stream_context_create(
			[
				'http' => [
					'timeout' => $this->timeout,
					'user_agent' => $this->agent,
					'redirect' => $this->redirect,
				]
			]
		);

		//Check inputs
		if (!empty($inputs)) {
			//Retrieve files content
			foreach($inputs as $input) {
				//Try to retrieve content
				if (($data = file_get_contents($input, false, $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 ($output[0] == '@') {
			//Check that we have a / separator between bundle name and path
			if (($pos = strpos($output, '/')) === false) {
				throw new Error(sprintf('Invalid output path "%s"', $output), $token->getLine(), $stream->getSourceContext());
			}
			//Resolve bundle prefix
			$output = $this->locator->locate(substr($output, 0, $pos)).substr($output, $pos + 1);
		}

		//Create output dir if not present
		if (!is_dir($dir = dirname($output))) {
			try {
				//XXX: set as 0777, symfony umask (0022) will reduce rights (0755)
				if (mkdir($dir, 0777, true) === false) {
					throw new \Exception();
				}
			} catch (\Exception $e) {
				throw new Error(sprintf('Output directory "%s" do not exists and unable to create it', $dir), $token->getLine(), $stream->getSourceContext(), $e);
			}
		}

		//Send file content
		//XXX: to avoid partial content in reverse cache we use atomic rotation write, unlink and move
		try {
			if (file_put_contents($output.'.new', $content) === false) {
				throw new \Exception();
			}
		} catch(\Exception $e) {
			throw new Error(sprintf('Unable to write to: %s', $output.'.new'), $token->getLine(), $stream->getSourceContext(), $e);
		}

		//Remove old file
		if (is_file($output)) {
			try {
				if (unlink($output) === false) {
					throw new \Exception();
				}
			} catch (\Exception $e) {
				throw new Error(sprintf('Unable to unlink: %s', $output), $token->getLine(), $stream->getSourceContext(), $e);
			}
		}

		//Rename it
		try {
			if (rename($output.'.new', $output) === false) {
				throw new \Exception();
			}
		} catch (\Exception $e) {
			throw new Error(sprintf('Unable to rename: %s to %s', $output.'.new', $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 class $token The \Twig\Token instance
	 *
	 * @return bool
	 */
	public function testEndTag(Token $token) {
		return $token->test(['end'.$this->getTag()]);
	}
}