<?php
namespace W3TCL\YuiCssMin;

class Command
{
	const SUCCESS_EXIT = 0;
	const FAILURE_EXIT = 1;

	protected $stats = array();

	public static function main()
	{
		$command = new self;
		$command->run();
	}

	public function run()
	{
		$opts = getopt(
			'hi:o:',
			array(
				'help',
				'input:',
				'output:',
				'dry-run',
				'keep-sourcemap',
				'keep-sourcemap-comment',
				'linebreak-position:',
				'memory-limit:',
				'pcre-backtrack-limit:',
				'pcre-recursion-limit:',
				'remove-important-comments'
			)
		);

		$help = $this->getOpt(array('h', 'help'), $opts);
		$input = $this->getOpt(array('i', 'input'), $opts);
		$output = $this->getOpt(array('o', 'output'), $opts);
		$dryrun = $this->getOpt('dry-run', $opts);
		$keepSourceMapComment = $this->getOpt(array('keep-sourcemap', 'keep-sourcemap-comment'), $opts);
		$linebreakPosition = $this->getOpt('linebreak-position', $opts);
		$memoryLimit = $this->getOpt('memory-limit', $opts);
		$backtrackLimit = $this->getOpt('pcre-backtrack-limit', $opts);
		$recursionLimit = $this->getOpt('pcre-recursion-limit', $opts);
		$removeImportantComments = $this->getOpt('remove-important-comments', $opts);

		if (!is_null($help)) {
			$this->showHelp();
			die( esc_html( self::SUCCESS_EXIT ) );
		}

		if (is_null($input)) {
			fwrite(STDERR, '-i <file> argument is missing' . PHP_EOL);
			$this->showHelp();
			die( esc_html( self::FAILURE_EXIT ) );
		}

		if (!is_readable($input)) {
			fwrite(STDERR, 'Input file is not readable' . PHP_EOL);
			die( esc_html( self::FAILURE_EXIT ) );
		}

		$css = file_get_contents($input);

		if ($css === false) {
			fwrite(STDERR, 'Input CSS code could not be retrieved from input file' . PHP_EOL);
			die( esc_html( self::FAILURE_EXIT ) );
		}

		$this->setStat('original-size', strlen($css));

		$cssmin = new Minifier;

		if (!is_null($keepSourceMapComment)) {
			$cssmin->keepSourceMapComment();
		}

		if (!is_null($removeImportantComments)) {
			$cssmin->removeImportantComments();
		}

		if (!is_null($linebreakPosition)) {
			$cssmin->setLineBreakPosition($linebreakPosition);
		}

		if (!is_null($memoryLimit)) {
			$cssmin->setMemoryLimit($memoryLimit);
		}

		if (!is_null($backtrackLimit)) {
			$cssmin->setPcreBacktrackLimit($backtrackLimit);
		}

		if (!is_null($recursionLimit)) {
			$cssmin->setPcreRecursionLimit($recursionLimit);
		}

		$this->setStat('compression-time-start', microtime(true));

		$css = $cssmin->run($css);

		$this->setStat('compression-time-end', microtime(true));
		$this->setStat('peak-memory-usage', memory_get_peak_usage(true));
		$this->setStat('compressed-size', strlen($css));

		if (!is_null($dryrun)) {
			$this->showStats();
			die( esc_html( self::SUCCESS_EXIT ) );
		}

		if (is_null($output)) {
			fwrite(STDOUT, $css . PHP_EOL);
			$this->showStats();
			die( esc_html( self::SUCCESS_EXIT ) );
		}

		if (!is_writable(dirname($output))) {
			fwrite(STDERR, 'Output file is not writable' . PHP_EOL);
			die( esc_html( self::FAILURE_EXIT ) );
		}

		if (file_put_contents($output, $css) === false) {
			fwrite(STDERR, 'Compressed CSS code could not be saved to output file' . PHP_EOL);
			die( esc_html( self::FAILURE_EXIT ) );
		}

		$this->showStats();

		die( esc_html( self::SUCCESS_EXIT ) );
	}

	protected function getOpt($opts, $options)
	{
		$value = null;

		if (is_string($opts)) {
			$opts = array($opts);
		}

		foreach ($opts as $opt) {
			if (array_key_exists($opt, $options)) {
				$value = $options[$opt];
				break;
			}
		}

		return $value;
	}

	protected function setStat($statName, $statValue)
	{
		$this->stats[$statName] = $statValue;
	}

	protected function formatBytes($size, $precision = 2)
	{
		$base = log($size, 1024);
		$suffixes = array('B', 'K', 'M', 'G', 'T');
		return round(pow(1024, $base - floor($base)), $precision) .' '. $suffixes[floor($base)];
	}

	protected function formatMicroSeconds($microSecs, $precision = 2)
	{
		// ms
		$time = round($microSecs * 1000, $precision);

		if ($time >= 60 * 1000) {
			$time = round($time / 60 * 1000, $precision) .' m'; // m
		} elseif ($time >= 1000) {
			$time = round($time / 1000, $precision) .' s'; // s
		} else {
			$time .= ' ms';
		}

		return $time;
	}

	protected function showStats()
	{
		$spaceSavings = round((1 - ($this->stats['compressed-size'] / $this->stats['original-size'])) * 100, 2);
		$compressionRatio = round($this->stats['original-size'] / $this->stats['compressed-size'], 2);
		$compressionTime = $this->formatMicroSeconds(
			$this->stats['compression-time-end'] - $this->stats['compression-time-start']
		);
		$peakMemoryUsage = $this->formatBytes($this->stats['peak-memory-usage']);

		print esc_html(
			<<<EOT

------------------------------
CSSMIN STATS
------------------------------
Space savings:       {$spaceSavings} %
Compression ratio:   {$compressionRatio}:1
Compression time:    $compressionTime
Peak memory usage:   $peakMemoryUsage


EOT
		);
	}

	protected function showHelp()
	{
		print <<<'EOT'
Usage: cssmin [options] -i <file> [-o <file>]

  -i|--input <file>              File containing uncompressed CSS code.
  -o|--output <file>             File to use to save compressed CSS code.

Options:

  -h|--help                      Prints this usage information.
  --dry-run                      Performs a dry run displaying statistics.
  --keep-sourcemap[-comment]     Keeps the sourcemap special comment in the output.
  --linebreak-position <pos>     Splits long lines after a specific column in the output.
  --memory-limit <limit>         Sets the memory limit for this script.
  --pcre-backtrack-limit <limit> Sets the PCRE backtrack limit for this script.
  --pcre-recursion-limit <limit> Sets the PCRE recursion limit for this script.
  --remove-important-comments    Removes !important comments from output.

EOT;
	}
}
