diff options
author | sembrestels <sembrestels@riseup.net> | 2011-10-13 02:39:43 +0200 |
---|---|---|
committer | sembrestels <sembrestels@riseup.net> | 2011-10-13 02:39:43 +0200 |
commit | 090e2188026c76ac396c919b27404dc7cb110bf8 (patch) | |
tree | 9f7f3a1278aa0a09f168abdc0db98f7de1788870 /lib/dokuwiki/inc/DifferenceEngine.php | |
download | elgg-090e2188026c76ac396c919b27404dc7cb110bf8.tar.gz elgg-090e2188026c76ac396c919b27404dc7cb110bf8.tar.bz2 |
Dokuwiki module for Elgg 1.7
Diffstat (limited to 'lib/dokuwiki/inc/DifferenceEngine.php')
-rw-r--r-- | lib/dokuwiki/inc/DifferenceEngine.php | 1066 |
1 files changed, 1066 insertions, 0 deletions
diff --git a/lib/dokuwiki/inc/DifferenceEngine.php b/lib/dokuwiki/inc/DifferenceEngine.php new file mode 100644 index 000000000..e28826c1f --- /dev/null +++ b/lib/dokuwiki/inc/DifferenceEngine.php @@ -0,0 +1,1066 @@ +<?php +/** + * A PHP diff engine for phpwiki. (Taken from phpwiki-1.3.3) + * + * Additions by Axel Boldt for MediaWiki + * + * @copyright (C) 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org> + * @license You may copy this code freely under the conditions of the GPL. + */ +define('USE_ASSERTS', function_exists('assert')); + +class _DiffOp { + var $type; + var $orig; + var $closing; + + function reverse() { + trigger_error("pure virtual", E_USER_ERROR); + } + + function norig() { + return $this->orig ? sizeof($this->orig) : 0; + } + + function nclosing() { + return $this->closing ? sizeof($this->closing) : 0; + } +} + +class _DiffOp_Copy extends _DiffOp { + var $type = 'copy'; + + function _DiffOp_Copy ($orig, $closing = false) { + if (!is_array($closing)) + $closing = $orig; + $this->orig = $orig; + $this->closing = $closing; + } + + function reverse() { + return new _DiffOp_Copy($this->closing, $this->orig); + } +} + +class _DiffOp_Delete extends _DiffOp { + var $type = 'delete'; + + function _DiffOp_Delete ($lines) { + $this->orig = $lines; + $this->closing = false; + } + + function reverse() { + return new _DiffOp_Add($this->orig); + } +} + +class _DiffOp_Add extends _DiffOp { + var $type = 'add'; + + function _DiffOp_Add ($lines) { + $this->closing = $lines; + $this->orig = false; + } + + function reverse() { + return new _DiffOp_Delete($this->closing); + } +} + +class _DiffOp_Change extends _DiffOp { + var $type = 'change'; + + function _DiffOp_Change ($orig, $closing) { + $this->orig = $orig; + $this->closing = $closing; + } + + function reverse() { + return new _DiffOp_Change($this->closing, $this->orig); + } +} + + +/** + * Class used internally by Diff to actually compute the diffs. + * + * The algorithm used here is mostly lifted from the perl module + * Algorithm::Diff (version 1.06) by Ned Konz, which is available at: + * http://www.perl.com/CPAN/authors/id/N/NE/NEDKONZ/Algorithm-Diff-1.06.zip + * + * More ideas are taken from: + * http://www.ics.uci.edu/~eppstein/161/960229.html + * + * Some ideas are (and a bit of code) are from from analyze.c, from GNU + * diffutils-2.7, which can be found at: + * ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz + * + * closingly, some ideas (subdivision by NCHUNKS > 2, and some optimizations) + * are my own. + * + * @author Geoffrey T. Dairiki + * @access private + */ +class _DiffEngine +{ + function diff ($from_lines, $to_lines) { + $n_from = sizeof($from_lines); + $n_to = sizeof($to_lines); + + $this->xchanged = $this->ychanged = array(); + $this->xv = $this->yv = array(); + $this->xind = $this->yind = array(); + unset($this->seq); + unset($this->in_seq); + unset($this->lcs); + + // Skip leading common lines. + for ($skip = 0; $skip < $n_from && $skip < $n_to; $skip++) { + if ($from_lines[$skip] != $to_lines[$skip]) + break; + $this->xchanged[$skip] = $this->ychanged[$skip] = false; + } + // Skip trailing common lines. + $xi = $n_from; $yi = $n_to; + for ($endskip = 0; --$xi > $skip && --$yi > $skip; $endskip++) { + if ($from_lines[$xi] != $to_lines[$yi]) + break; + $this->xchanged[$xi] = $this->ychanged[$yi] = false; + } + + // Ignore lines which do not exist in both files. + for ($xi = $skip; $xi < $n_from - $endskip; $xi++) + $xhash[$from_lines[$xi]] = 1; + for ($yi = $skip; $yi < $n_to - $endskip; $yi++) { + $line = $to_lines[$yi]; + if ( ($this->ychanged[$yi] = empty($xhash[$line])) ) + continue; + $yhash[$line] = 1; + $this->yv[] = $line; + $this->yind[] = $yi; + } + for ($xi = $skip; $xi < $n_from - $endskip; $xi++) { + $line = $from_lines[$xi]; + if ( ($this->xchanged[$xi] = empty($yhash[$line])) ) + continue; + $this->xv[] = $line; + $this->xind[] = $xi; + } + + // Find the LCS. + $this->_compareseq(0, sizeof($this->xv), 0, sizeof($this->yv)); + + // Merge edits when possible + $this->_shift_boundaries($from_lines, $this->xchanged, $this->ychanged); + $this->_shift_boundaries($to_lines, $this->ychanged, $this->xchanged); + + // Compute the edit operations. + $edits = array(); + $xi = $yi = 0; + while ($xi < $n_from || $yi < $n_to) { + USE_ASSERTS && assert($yi < $n_to || $this->xchanged[$xi]); + USE_ASSERTS && assert($xi < $n_from || $this->ychanged[$yi]); + + // Skip matching "snake". + $copy = array(); + while ( $xi < $n_from && $yi < $n_to + && !$this->xchanged[$xi] && !$this->ychanged[$yi]) { + $copy[] = $from_lines[$xi++]; + ++$yi; + } + if ($copy) + $edits[] = new _DiffOp_Copy($copy); + + // Find deletes & adds. + $delete = array(); + while ($xi < $n_from && $this->xchanged[$xi]) + $delete[] = $from_lines[$xi++]; + + $add = array(); + while ($yi < $n_to && $this->ychanged[$yi]) + $add[] = $to_lines[$yi++]; + + if ($delete && $add) + $edits[] = new _DiffOp_Change($delete, $add); + elseif ($delete) + $edits[] = new _DiffOp_Delete($delete); + elseif ($add) + $edits[] = new _DiffOp_Add($add); + } + return $edits; + } + + + /** + * Divide the Largest Common Subsequence (LCS) of the sequences + * [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally + * sized segments. + * + * Returns (LCS, PTS). LCS is the length of the LCS. PTS is an + * array of NCHUNKS+1 (X, Y) indexes giving the diving points between + * sub sequences. The first sub-sequence is contained in [X0, X1), + * [Y0, Y1), the second in [X1, X2), [Y1, Y2) and so on. Note + * that (X0, Y0) == (XOFF, YOFF) and + * (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM). + * + * This function assumes that the first lines of the specified portions + * of the two files do not match, and likewise that the last lines do not + * match. The caller must trim matching lines from the beginning and end + * of the portions it is going to specify. + */ + function _diag ($xoff, $xlim, $yoff, $ylim, $nchunks) { + $flip = false; + + if ($xlim - $xoff > $ylim - $yoff) { + // Things seems faster (I'm not sure I understand why) + // when the shortest sequence in X. + $flip = true; + list ($xoff, $xlim, $yoff, $ylim) + = array( $yoff, $ylim, $xoff, $xlim); + } + + if ($flip) + for ($i = $ylim - 1; $i >= $yoff; $i--) + $ymatches[$this->xv[$i]][] = $i; + else + for ($i = $ylim - 1; $i >= $yoff; $i--) + $ymatches[$this->yv[$i]][] = $i; + + $this->lcs = 0; + $this->seq[0]= $yoff - 1; + $this->in_seq = array(); + $ymids[0] = array(); + + $numer = $xlim - $xoff + $nchunks - 1; + $x = $xoff; + for ($chunk = 0; $chunk < $nchunks; $chunk++) { + if ($chunk > 0) + for ($i = 0; $i <= $this->lcs; $i++) + $ymids[$i][$chunk-1] = $this->seq[$i]; + + $x1 = $xoff + (int)(($numer + ($xlim-$xoff)*$chunk) / $nchunks); + for ( ; $x < $x1; $x++) { + $line = $flip ? $this->yv[$x] : $this->xv[$x]; + if (empty($ymatches[$line])) + continue; + $matches = $ymatches[$line]; + reset($matches); + while (list ($junk, $y) = each($matches)) + if (empty($this->in_seq[$y])) { + $k = $this->_lcs_pos($y); + USE_ASSERTS && assert($k > 0); + $ymids[$k] = $ymids[$k-1]; + break; + } + while (list ($junk, $y) = each($matches)) { + if ($y > $this->seq[$k-1]) { + USE_ASSERTS && assert($y < $this->seq[$k]); + // Optimization: this is a common case: + // next match is just replacing previous match. + $this->in_seq[$this->seq[$k]] = false; + $this->seq[$k] = $y; + $this->in_seq[$y] = 1; + } + else if (empty($this->in_seq[$y])) { + $k = $this->_lcs_pos($y); + USE_ASSERTS && assert($k > 0); + $ymids[$k] = $ymids[$k-1]; + } + } + } + } + + $seps[] = $flip ? array($yoff, $xoff) : array($xoff, $yoff); + $ymid = $ymids[$this->lcs]; + for ($n = 0; $n < $nchunks - 1; $n++) { + $x1 = $xoff + (int)(($numer + ($xlim - $xoff) * $n) / $nchunks); + $y1 = $ymid[$n] + 1; + $seps[] = $flip ? array($y1, $x1) : array($x1, $y1); + } + $seps[] = $flip ? array($ylim, $xlim) : array($xlim, $ylim); + + return array($this->lcs, $seps); + } + + function _lcs_pos ($ypos) { + $end = $this->lcs; + if ($end == 0 || $ypos > $this->seq[$end]) { + $this->seq[++$this->lcs] = $ypos; + $this->in_seq[$ypos] = 1; + return $this->lcs; + } + + $beg = 1; + while ($beg < $end) { + $mid = (int)(($beg + $end) / 2); + if ( $ypos > $this->seq[$mid] ) + $beg = $mid + 1; + else + $end = $mid; + } + + USE_ASSERTS && assert($ypos != $this->seq[$end]); + + $this->in_seq[$this->seq[$end]] = false; + $this->seq[$end] = $ypos; + $this->in_seq[$ypos] = 1; + return $end; + } + + /** + * Find LCS of two sequences. + * + * The results are recorded in the vectors $this->{x,y}changed[], by + * storing a 1 in the element for each line that is an insertion + * or deletion (ie. is not in the LCS). + * + * The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1. + * + * Note that XLIM, YLIM are exclusive bounds. + * All line numbers are origin-0 and discarded lines are not counted. + */ + function _compareseq ($xoff, $xlim, $yoff, $ylim) { + // Slide down the bottom initial diagonal. + while ($xoff < $xlim && $yoff < $ylim + && $this->xv[$xoff] == $this->yv[$yoff]) { + ++$xoff; + ++$yoff; + } + + // Slide up the top initial diagonal. + while ($xlim > $xoff && $ylim > $yoff + && $this->xv[$xlim - 1] == $this->yv[$ylim - 1]) { + --$xlim; + --$ylim; + } + + if ($xoff == $xlim || $yoff == $ylim) + $lcs = 0; + else { + // This is ad hoc but seems to work well. + //$nchunks = sqrt(min($xlim - $xoff, $ylim - $yoff) / 2.5); + //$nchunks = max(2,min(8,(int)$nchunks)); + $nchunks = min(7, $xlim - $xoff, $ylim - $yoff) + 1; + list ($lcs, $seps) + = $this->_diag($xoff,$xlim,$yoff, $ylim,$nchunks); + } + + if ($lcs == 0) { + // X and Y sequences have no common subsequence: + // mark all changed. + while ($yoff < $ylim) + $this->ychanged[$this->yind[$yoff++]] = 1; + while ($xoff < $xlim) + $this->xchanged[$this->xind[$xoff++]] = 1; + } + else { + // Use the partitions to split this problem into subproblems. + reset($seps); + $pt1 = $seps[0]; + while ($pt2 = next($seps)) { + $this->_compareseq ($pt1[0], $pt2[0], $pt1[1], $pt2[1]); + $pt1 = $pt2; + } + } + } + + /** + * Adjust inserts/deletes of identical lines to join changes + * as much as possible. + * + * We do something when a run of changed lines include a + * line at one end and has an excluded, identical line at the other. + * We are free to choose which identical line is included. + * `compareseq' usually chooses the one at the beginning, + * but usually it is cleaner to consider the following identical line + * to be the "change". + * + * This is extracted verbatim from analyze.c (GNU diffutils-2.7). + */ + function _shift_boundaries ($lines, &$changed, $other_changed) { + $i = 0; + $j = 0; + + USE_ASSERTS && assert('sizeof($lines) == sizeof($changed)'); + $len = sizeof($lines); + $other_len = sizeof($other_changed); + + while (1) { + /* + * Scan forwards to find beginning of another run of changes. + * Also keep track of the corresponding point in the other file. + * + * Throughout this code, $i and $j are adjusted together so that + * the first $i elements of $changed and the first $j elements + * of $other_changed both contain the same number of zeros + * (unchanged lines). + * Furthermore, $j is always kept so that $j == $other_len or + * $other_changed[$j] == false. + */ + while ($j < $other_len && $other_changed[$j]) + $j++; + + while ($i < $len && ! $changed[$i]) { + USE_ASSERTS && assert('$j < $other_len && ! $other_changed[$j]'); + $i++; $j++; + while ($j < $other_len && $other_changed[$j]) + $j++; + } + + if ($i == $len) + break; + + $start = $i; + + // Find the end of this run of changes. + while (++$i < $len && $changed[$i]) + continue; + + do { + /* + * Record the length of this run of changes, so that + * we can later determine whether the run has grown. + */ + $runlength = $i - $start; + + /* + * Move the changed region back, so long as the + * previous unchanged line matches the last changed one. + * This merges with previous changed regions. + */ + while ($start > 0 && $lines[$start - 1] == $lines[$i - 1]) { + $changed[--$start] = 1; + $changed[--$i] = false; + while ($start > 0 && $changed[$start - 1]) + $start--; + USE_ASSERTS && assert('$j > 0'); + while ($other_changed[--$j]) + continue; + USE_ASSERTS && assert('$j >= 0 && !$other_changed[$j]'); + } + + /* + * Set CORRESPONDING to the end of the changed run, at the last + * point where it corresponds to a changed run in the other file. + * CORRESPONDING == LEN means no such point has been found. + */ + $corresponding = $j < $other_len ? $i : $len; + + /* + * Move the changed region forward, so long as the + * first changed line matches the following unchanged one. + * This merges with following changed regions. + * Do this second, so that if there are no merges, + * the changed region is moved forward as far as possible. + */ + while ($i < $len && $lines[$start] == $lines[$i]) { + $changed[$start++] = false; + $changed[$i++] = 1; + while ($i < $len && $changed[$i]) + $i++; + + USE_ASSERTS && assert('$j < $other_len && ! $other_changed[$j]'); + $j++; + if ($j < $other_len && $other_changed[$j]) { + $corresponding = $i; + while ($j < $other_len && $other_changed[$j]) + $j++; + } + } + } while ($runlength != $i - $start); + + /* + * If possible, move the fully-merged run of changes + * back to a corresponding run in the other file. + */ + while ($corresponding < $i) { + $changed[--$start] = 1; + $changed[--$i] = 0; + USE_ASSERTS && assert('$j > 0'); + while ($other_changed[--$j]) + continue; + USE_ASSERTS && assert('$j >= 0 && !$other_changed[$j]'); + } + } + } +} + +/** + * Class representing a 'diff' between two sequences of strings. + */ +class Diff +{ + var $edits; + + /** + * Constructor. + * Computes diff between sequences of strings. + * + * @param $from_lines array An array of strings. + * (Typically these are lines from a file.) + * @param $to_lines array An array of strings. + */ + function Diff($from_lines, $to_lines) { + $eng = new _DiffEngine; + $this->edits = $eng->diff($from_lines, $to_lines); + //$this->_check($from_lines, $to_lines); + } + + /** + * Compute reversed Diff. + * + * SYNOPSIS: + * + * $diff = new Diff($lines1, $lines2); + * $rev = $diff->reverse(); + * @return object A Diff object representing the inverse of the + * original diff. + */ + function reverse () { + $rev = $this; + $rev->edits = array(); + foreach ($this->edits as $edit) { + $rev->edits[] = $edit->reverse(); + } + return $rev; + } + + /** + * Check for empty diff. + * + * @return bool True iff two sequences were identical. + */ + function isEmpty () { + foreach ($this->edits as $edit) { + if ($edit->type != 'copy') + return false; + } + return true; + } + + /** + * Compute the length of the Longest Common Subsequence (LCS). + * + * This is mostly for diagnostic purposed. + * + * @return int The length of the LCS. + */ + function lcs () { + $lcs = 0; + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $lcs += sizeof($edit->orig); + } + return $lcs; + } + + /** + * Get the original set of lines. + * + * This reconstructs the $from_lines parameter passed to the + * constructor. + * + * @return array The original sequence of strings. + */ + function orig() { + $lines = array(); + + foreach ($this->edits as $edit) { + if ($edit->orig) + array_splice($lines, sizeof($lines), 0, $edit->orig); + } + return $lines; + } + + /** + * Get the closing set of lines. + * + * This reconstructs the $to_lines parameter passed to the + * constructor. + * + * @return array The sequence of strings. + */ + function closing() { + $lines = array(); + + foreach ($this->edits as $edit) { + if ($edit->closing) + array_splice($lines, sizeof($lines), 0, $edit->closing); + } + return $lines; + } + + /** + * Check a Diff for validity. + * + * This is here only for debugging purposes. + */ + function _check ($from_lines, $to_lines) { + if (serialize($from_lines) != serialize($this->orig())) + trigger_error("Reconstructed original doesn't match", E_USER_ERROR); + if (serialize($to_lines) != serialize($this->closing())) + trigger_error("Reconstructed closing doesn't match", E_USER_ERROR); + + $rev = $this->reverse(); + if (serialize($to_lines) != serialize($rev->orig())) + trigger_error("Reversed original doesn't match", E_USER_ERROR); + if (serialize($from_lines) != serialize($rev->closing())) + trigger_error("Reversed closing doesn't match", E_USER_ERROR); + + + $prevtype = 'none'; + foreach ($this->edits as $edit) { + if ( $prevtype == $edit->type ) + trigger_error("Edit sequence is non-optimal", E_USER_ERROR); + $prevtype = $edit->type; + } + + $lcs = $this->lcs(); + trigger_error("Diff okay: LCS = $lcs", E_USER_NOTICE); + } +} + +/** + * FIXME: bad name. + */ +class MappedDiff +extends Diff +{ + /** + * Constructor. + * + * Computes diff between sequences of strings. + * + * This can be used to compute things like + * case-insensitve diffs, or diffs which ignore + * changes in white-space. + * + * @param $from_lines array An array of strings. + * (Typically these are lines from a file.) + * + * @param $to_lines array An array of strings. + * + * @param $mapped_from_lines array This array should + * have the same size number of elements as $from_lines. + * The elements in $mapped_from_lines and + * $mapped_to_lines are what is actually compared + * when computing the diff. + * + * @param $mapped_to_lines array This array should + * have the same number of elements as $to_lines. + */ + function MappedDiff($from_lines, $to_lines, + $mapped_from_lines, $mapped_to_lines) { + + assert(sizeof($from_lines) == sizeof($mapped_from_lines)); + assert(sizeof($to_lines) == sizeof($mapped_to_lines)); + + $this->Diff($mapped_from_lines, $mapped_to_lines); + + $xi = $yi = 0; + for ($i = 0; $i < sizeof($this->edits); $i++) { + $orig = &$this->edits[$i]->orig; + if (is_array($orig)) { + $orig = array_slice($from_lines, $xi, sizeof($orig)); + $xi += sizeof($orig); + } + + $closing = &$this->edits[$i]->closing; + if (is_array($closing)) { + $closing = array_slice($to_lines, $yi, sizeof($closing)); + $yi += sizeof($closing); + } + } + } +} + +/** + * A class to format Diffs + * + * This class formats the diff in classic diff format. + * It is intended that this class be customized via inheritance, + * to obtain fancier outputs. + */ +class DiffFormatter +{ + /** + * Number of leading context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + var $leading_context_lines = 0; + + /** + * Number of trailing context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + var $trailing_context_lines = 0; + + /** + * Format a diff. + * + * @param $diff object A Diff object. + * @return string The formatted output. + */ + function format($diff) { + + $xi = $yi = 1; + $block = false; + $context = array(); + + $nlead = $this->leading_context_lines; + $ntrail = $this->trailing_context_lines; + + $this->_start_diff(); + + foreach ($diff->edits as $edit) { + if ($edit->type == 'copy') { + if (is_array($block)) { + if (sizeof($edit->orig) <= $nlead + $ntrail) { + $block[] = $edit; + } + else{ + if ($ntrail) { + $context = array_slice($edit->orig, 0, $ntrail); + $block[] = new _DiffOp_Copy($context); + } + $this->_block($x0, $ntrail + $xi - $x0, + $y0, $ntrail + $yi - $y0, + $block); + $block = false; + } + } + $context = $edit->orig; + } + else { + if (! is_array($block)) { + $context = array_slice($context, sizeof($context) - $nlead); + $x0 = $xi - sizeof($context); + $y0 = $yi - sizeof($context); + $block = array(); + if ($context) + $block[] = new _DiffOp_Copy($context); + } + $block[] = $edit; + } + + if ($edit->orig) + $xi += sizeof($edit->orig); + if ($edit->closing) + $yi += sizeof($edit->closing); + } + + if (is_array($block)) + $this->_block($x0, $xi - $x0, + $y0, $yi - $y0, + $block); + + return $this->_end_diff(); + } + + function _block($xbeg, $xlen, $ybeg, $ylen, &$edits) { + $this->_start_block($this->_block_header($xbeg, $xlen, $ybeg, $ylen)); + foreach ($edits as $edit) { + if ($edit->type == 'copy') + $this->_context($edit->orig); + elseif ($edit->type == 'add') + $this->_added($edit->closing); + elseif ($edit->type == 'delete') + $this->_deleted($edit->orig); + elseif ($edit->type == 'change') + $this->_changed($edit->orig, $edit->closing); + else + trigger_error("Unknown edit type", E_USER_ERROR); + } + $this->_end_block(); + } + + function _start_diff() { + ob_start(); + } + + function _end_diff() { + $val = ob_get_contents(); + ob_end_clean(); + return $val; + } + + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + if ($xlen > 1) + $xbeg .= "," . ($xbeg + $xlen - 1); + if ($ylen > 1) + $ybeg .= "," . ($ybeg + $ylen - 1); + + return $xbeg . ($xlen ? ($ylen ? 'c' : 'd') : 'a') . $ybeg; + } + + function _start_block($header) { + echo $header; + } + + function _end_block() { + } + + function _lines($lines, $prefix = ' ') { + foreach ($lines as $line) + echo "$prefix $line\n"; + } + + function _context($lines) { + $this->_lines($lines); + } + + function _added($lines) { + $this->_lines($lines, ">"); + } + function _deleted($lines) { + $this->_lines($lines, "<"); + } + + function _changed($orig, $closing) { + $this->_deleted($orig); + echo "---\n"; + $this->_added($closing); + } +} + + +/** + * Additions by Axel Boldt follow, partly taken from diff.php, phpwiki-1.3.3 + * + */ + +define('NBSP', "\xC2\xA0"); // utf-8 non-breaking space. + +class _HWLDF_WordAccumulator { + function _HWLDF_WordAccumulator () { + $this->_lines = array(); + $this->_line = ''; + $this->_group = ''; + $this->_tag = ''; + } + + function _flushGroup ($new_tag) { + if ($this->_group !== '') { + if ($this->_tag == 'mark') + $this->_line .= '<strong>'.$this->_group.'</strong>'; + else + $this->_line .= $this->_group; + } + $this->_group = ''; + $this->_tag = $new_tag; + } + + function _flushLine ($new_tag) { + $this->_flushGroup($new_tag); + if ($this->_line != '') + $this->_lines[] = $this->_line; + $this->_line = ''; + } + + function addWords ($words, $tag = '') { + if ($tag != $this->_tag) + $this->_flushGroup($tag); + + foreach ($words as $word) { + // new-line should only come as first char of word. + if ($word == '') + continue; + if ($word[0] == "\n") { + $this->_group .= NBSP; + $this->_flushLine($tag); + $word = substr($word, 1); + } + assert(!strstr($word, "\n")); + $this->_group .= $word; + } + } + + function getLines() { + $this->_flushLine('~done'); + return $this->_lines; + } +} + +class WordLevelDiff extends MappedDiff +{ + function WordLevelDiff ($orig_lines, $closing_lines) { + list ($orig_words, $orig_stripped) = $this->_split($orig_lines); + list ($closing_words, $closing_stripped) = $this->_split($closing_lines); + + + $this->MappedDiff($orig_words, $closing_words, + $orig_stripped, $closing_stripped); + } + + function _split($lines) { + // FIXME: fix POSIX char class. +# if (!preg_match_all('/ ( [^\S\n]+ | [[:alnum:]]+ | . ) (?: (?!< \n) [^\S\n])? /xs', + if (!preg_match_all('/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xs', + implode("\n", $lines), + $m)) { + return array(array(''), array('')); + } + return array($m[0], $m[1]); + } + + function orig () { + $orig = new _HWLDF_WordAccumulator; + + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $orig->addWords($edit->orig); + elseif ($edit->orig) + $orig->addWords($edit->orig, 'mark'); + } + return $orig->getLines(); + } + + function closing () { + $closing = new _HWLDF_WordAccumulator; + + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $closing->addWords($edit->closing); + elseif ($edit->closing) + $closing->addWords($edit->closing, 'mark'); + } + return $closing->getLines(); + } +} + +/** + * "Unified" diff formatter. + * + * This class formats the diff in classic "unified diff" format. + */ +class UnifiedDiffFormatter extends DiffFormatter +{ + function UnifiedDiffFormatter($context_lines = 4) { + $this->leading_context_lines = $context_lines; + $this->trailing_context_lines = $context_lines; + } + + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + if ($xlen != 1) + $xbeg .= "," . $xlen; + if ($ylen != 1) + $ybeg .= "," . $ylen; + return "@@ -$xbeg +$ybeg @@\n"; + } + + function _added($lines) { + $this->_lines($lines, "+"); + } + function _deleted($lines) { + $this->_lines($lines, "-"); + } + function _changed($orig, $final) { + $this->_deleted($orig); + $this->_added($final); + } +} + +/** + * Wikipedia Table style diff formatter. + * + */ +class TableDiffFormatter extends DiffFormatter +{ + function TableDiffFormatter() { + $this->leading_context_lines = 2; + $this->trailing_context_lines = 2; + } + + function _pre($text){ + $text = htmlspecialchars($text); + $text = str_replace(' ',' ',$text); + if($text{0} == ' ') $text = ' '.substr($text,1); + return $text; + } + + function _block_header( $xbeg, $xlen, $ybeg, $ylen ) { + global $lang; + $l1 = $lang['line'].' '.$xbeg; + $l2 = $lang['line'].' '.$ybeg; + $r = '<tr><td class="diff-blockheader" colspan="2">'.$l1.":</td>\n" . + '<td class="diff-blockheader" colspan="2">'.$l2.":</td></tr>\n"; + return $r; + } + + function _start_block( $header ) { + print( $header ); + } + + function _end_block() { + } + + function _lines( $lines, $prefix=' ', $color="white" ) { + } + + function addedLine( $line ) { + $line = str_replace(' ',' ',$line); + if($line{0} == ' ') $line = ' '.substr($line,1); + return '<td>+</td><td class="diff-addedline">' . + $line.'</td>'; + } + + function deletedLine( $line ) { + $line = str_replace(' ',' ',$line); + if($line{0} == ' ') $line = ' '.substr($line,1); + return '<td>-</td><td class="diff-deletedline">' . + $line.'</td>'; + } + + function emptyLine() { + //$line = str_replace(' ',' ',$line); + return '<td colspan="2"> </td>'; + } + + function contextLine( $line ) { + $line = str_replace(' ',' ',$line); + if($line{0} == ' ') $line = ' '.substr($line,1); + return '<td> </td><td class="diff-context">'.$line.'</td>'; + } + + function _added($lines) { + foreach ($lines as $line) { + print( '<tr>' . $this->emptyLine() . + $this->addedLine( $line ) . "</tr>\n" ); + } + } + + function _deleted($lines) { + foreach ($lines as $line) { + print( '<tr>' . $this->deletedLine( $line ) . + $this->emptyLine() . "</tr>\n" ); + } + } + + function _context( $lines ) { + foreach ($lines as $line) { + print( '<tr>' . $this->contextLine( $line ) . + $this->contextLine( $line ) . "</tr>\n" ); + } + } + + function _changed( $orig, $closing ) { + $diff = new WordLevelDiff( $orig, $closing ); + $del = $diff->orig(); + $add = $diff->closing(); + + while ( $line = array_shift( $del ) ) { + $aline = array_shift( $add ); + print( '<tr>' . $this->deletedLine( $line ) . + $this->addedLine( $aline ) . "</tr>\n" ); + } + $this->_added( $add ); # If any leftovers + } +} + + +//Setup VIM: ex: et ts=2 enc=utf-8 : |