Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Component\Diff;
Chris@0: 
Chris@0: use Drupal\Component\Diff\Engine\DiffOpCopy;
Chris@0: 
Chris@0: /**
Chris@0:  * A class to format Diffs
Chris@0:  *
Chris@0:  * This class formats the diff in classic diff format.
Chris@0:  * It is intended that this class be customized via inheritance,
Chris@0:  * to obtain fancier outputs.
Chris@0:  * @todo document
Chris@0:  * @private
Chris@0:  * @subpackage DifferenceEngine
Chris@0:  */
Chris@0: class DiffFormatter {
Chris@0:   /**
Chris@0:    * Should a block header be shown?
Chris@0:    */
Chris@0:   public $show_header = TRUE;
Chris@0: 
Chris@0:   /**
Chris@0:    * Number of leading context "lines" to preserve.
Chris@0:    *
Chris@0:    * This should be left at zero for this class, but subclasses
Chris@0:    * may want to set this to other values.
Chris@0:    */
Chris@0:   public $leading_context_lines = 0;
Chris@0: 
Chris@0:   /**
Chris@0:    * Number of trailing context "lines" to preserve.
Chris@0:    *
Chris@0:    * This should be left at zero for this class, but subclasses
Chris@0:    * may want to set this to other values.
Chris@0:    */
Chris@0:   public $trailing_context_lines = 0;
Chris@0: 
Chris@0:   /**
Chris@0:    * The line stats.
Chris@0:    *
Chris@0:    * @var array
Chris@0:    */
Chris@0:   protected $line_stats = [
Chris@0:     'counter' => ['x' => 0, 'y' => 0],
Chris@0:     'offset' => ['x' => 0, 'y' => 0],
Chris@0:   ];
Chris@0: 
Chris@0:   /**
Chris@0:    * Format a diff.
Chris@0:    *
Chris@0:    * @param \Drupal\Component\Diff\Diff $diff
Chris@0:    *   A Diff object.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   The formatted output.
Chris@0:    */
Chris@0:   public function format(Diff $diff) {
Chris@0:     $xi = $yi = 1;
Chris@0:     $block = FALSE;
Chris@0:     $context = [];
Chris@0: 
Chris@0:     $nlead = $this->leading_context_lines;
Chris@0:     $ntrail = $this->trailing_context_lines;
Chris@0: 
Chris@0:     $this->_start_diff();
Chris@0: 
Chris@0:     foreach ($diff->getEdits() as $edit) {
Chris@0:       if ($edit->type == 'copy') {
Chris@0:         if (is_array($block)) {
Chris@0:           if (sizeof($edit->orig) <= $nlead + $ntrail) {
Chris@0:             $block[] = $edit;
Chris@0:           }
Chris@0:           else {
Chris@0:             if ($ntrail) {
Chris@0:               $context = array_slice($edit->orig, 0, $ntrail);
Chris@0:               $block[] = new DiffOpCopy($context);
Chris@0:             }
Chris@0:             $this->_block($x0, $ntrail + $xi - $x0, $y0, $ntrail + $yi - $y0, $block);
Chris@0:             $block = FALSE;
Chris@0:           }
Chris@0:         }
Chris@0:         $context = $edit->orig;
Chris@0:       }
Chris@0:       else {
Chris@0:         if (!is_array($block)) {
Chris@0:           $context = array_slice($context, sizeof($context) - $nlead);
Chris@0:           $x0 = $xi - sizeof($context);
Chris@0:           $y0 = $yi - sizeof($context);
Chris@0:           $block = [];
Chris@0:           if ($context) {
Chris@0:             $block[] = new DiffOpCopy($context);
Chris@0:           }
Chris@0:         }
Chris@0:         $block[] = $edit;
Chris@0:       }
Chris@0: 
Chris@0:       if ($edit->orig) {
Chris@0:         $xi += sizeof($edit->orig);
Chris@0:       }
Chris@0:       if ($edit->closing) {
Chris@0:         $yi += sizeof($edit->closing);
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     if (is_array($block)) {
Chris@0:       $this->_block($x0, $xi - $x0, $y0, $yi - $y0, $block);
Chris@0:     }
Chris@0:     $end = $this->_end_diff();
Chris@0: 
Chris@0:     if (!empty($xi)) {
Chris@0:       $this->line_stats['counter']['x'] += $xi;
Chris@0:     }
Chris@0:     if (!empty($yi)) {
Chris@0:       $this->line_stats['counter']['y'] += $yi;
Chris@0:     }
Chris@0: 
Chris@0:     return $end;
Chris@0:   }
Chris@0: 
Chris@0:   protected function _block($xbeg, $xlen, $ybeg, $ylen, &$edits) {
Chris@0:     $this->_start_block($this->_block_header($xbeg, $xlen, $ybeg, $ylen));
Chris@0:     foreach ($edits as $edit) {
Chris@0:       if ($edit->type == 'copy') {
Chris@0:         $this->_context($edit->orig);
Chris@0:       }
Chris@0:       elseif ($edit->type == 'add') {
Chris@0:         $this->_added($edit->closing);
Chris@0:       }
Chris@0:       elseif ($edit->type == 'delete') {
Chris@0:         $this->_deleted($edit->orig);
Chris@0:       }
Chris@0:       elseif ($edit->type == 'change') {
Chris@0:         $this->_changed($edit->orig, $edit->closing);
Chris@0:       }
Chris@0:       else {
Chris@0:         trigger_error('Unknown edit type', E_USER_ERROR);
Chris@0:       }
Chris@0:     }
Chris@0:     $this->_end_block();
Chris@0:   }
Chris@0: 
Chris@0:   protected function _start_diff() {
Chris@0:     ob_start();
Chris@0:   }
Chris@0: 
Chris@0:   protected function _end_diff() {
Chris@0:     $val = ob_get_contents();
Chris@0:     ob_end_clean();
Chris@0:     return $val;
Chris@0:   }
Chris@0: 
Chris@0:   protected function _block_header($xbeg, $xlen, $ybeg, $ylen) {
Chris@0:     if ($xlen > 1) {
Chris@0:       $xbeg .= "," . ($xbeg + $xlen - 1);
Chris@0:     }
Chris@0:     if ($ylen > 1) {
Chris@0:       $ybeg .= "," . ($ybeg + $ylen - 1);
Chris@0:     }
Chris@0: 
Chris@0:     return $xbeg . ($xlen ? ($ylen ? 'c' : 'd') : 'a') . $ybeg;
Chris@0:   }
Chris@0: 
Chris@0:   protected function _start_block($header) {
Chris@0:     if ($this->show_header) {
Chris@0:       echo $header . "\n";
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   protected function _end_block() {
Chris@0:   }
Chris@0: 
Chris@0:   protected function _lines($lines, $prefix = ' ') {
Chris@0:     foreach ($lines as $line) {
Chris@0:       echo "$prefix $line\n";
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   protected function _context($lines) {
Chris@0:     $this->_lines($lines);
Chris@0:   }
Chris@0: 
Chris@0:   protected function _added($lines) {
Chris@0:     $this->_lines($lines, '>');
Chris@0:   }
Chris@0: 
Chris@0:   protected function _deleted($lines) {
Chris@0:     $this->_lines($lines, '<');
Chris@0:   }
Chris@0: 
Chris@0:   protected function _changed($orig, $closing) {
Chris@0:     $this->_deleted($orig);
Chris@0:     echo "---\n";
Chris@0:     $this->_added($closing);
Chris@0:   }
Chris@0: 
Chris@0: }