login/commits: syntax highlighting of diff lines

[minimedit.git] / login / commits / index.php

<?php
if (!$User->admin('edit')) {
        require '403.inc.html';
        return;
}

$hash = ltrim($Page->path, '/');
if (!$hash) {
        return TRUE;
}

$this->title = "Wijzigingen in ".strtoupper($hash);
print "<h2>{$this->title}</h2>\n";

$gitcmd = "git show "
        . "--word-diff=porcelain --no-prefix --pretty='%H%n%at\t%an\t%w(0,0,1)%B' "
        . escapeshellarg($hash);
$log = popen($gitcmd, 'r');
if (!$log or strpos(fgets($log), $hash) !== 0) {
        $Page->place['warn'] = "Kon inhoud niet ophalen met <code>$gitcmd</code>";
        return;
}

# read metadata and commit message
list ($atime, $author, $msg) = explode("\t", fgets($log), 3);
while ( $line = fgets($log) ) {
        if ($line == "\n") {
                fgets($log); // assume another empty line
                break;
        }
        $msg .= substr($line, 1);
}

# commit head
print '<p>';
printf('<small class="date">%s • %s</small>',
        htmlspecialchars($author), strftime('%F %H:%M', $atime)
);
print "\n".nl2br(htmlspecialchars($msg));
print "</p>\n";

print '<style>
.diff {
        white-space: pre-wrap;
        white-space: break-spaces;
        font-family: monospace;
}
td:first-of-type.change,
del {
        background: #F002;
        text-decoration: none;
}
td:last-of-type.change,
ins {
        background: #0F02;
        text-decoration: none;
}
.diff .head {
        background: #00F2;
}
</style>';

# body
$row = $ln = NULL;
$col = ['', ''];
print '<table class="diff">';
while ( $line = fgets($log) ) {
        preg_match(isset($ln) ? '/^(\W|\S+ )(.*)/' : '/^(\S+ )(.*)/', $line, $part);
        $body = htmlspecialchars($part[2]);
        switch ($part[1]) {
        case 'diff ':
                # file start
                if (preg_match('/^--git (.+) (.*)/', $part[2], $diffhead)) {
                        $row = "$diffhead[1]";
                        if ($diffhead[1] !== $diffhead[2]) {
                                $row .= " → $diffhead[2]";
                        }
                }
                else {
                        $row = '?';
                }
                $ln = NULL;
                break;
        case '@@ ':
                # chunk start
                if (preg_match('/^[-](\d+)(?:,\d+)? [+](\d+)(?:,\d+)? @@/', $part[2], $diffstart)) {
                        array_shift($diffstart);
                        $ln = $diffstart;
                }
                else {
                        $ln = ['?', '?']; # unrecognised diff header
                }
                print '<tr class="head"><td colspan="4">'.$row.'</tr>'."\n";
                break;
        case '-':
                $col[0] .= "<del>$body</del>";
                break;
        case '+':
                $col[1] .= "<ins>$body</ins>";
                break;
        case ' ':
                $col[0] .= $body;
                $col[1] .= $body;
                break;
        case '~':
                # part end
                print '<tr>';
                foreach ($col as $i => $line) {
                        if (empty($line)) {
                                print '<th><td>';
                                continue;
                        }
                        printf('<th>%s</th><td%s>%s</td>',
                                $ln[$i]++,
                                $col[0] == $col[1] ? '' : ' class="change"',
                                $line
                        );
                }
                print "</tr>\n";
                $col = ['', ''];
                break;
        }
}
print "</table>\n";
pclose($log);

return;