gitweb: New improved patchset view

Replace "gitweb diff header" with its full sha1 of blobs and replace
it by "git diff" header and extended diff header. Change also somewhat
highlighting of diffs.

Added `file_type_long' subroutine to convert file mode in octal to
file type description (only for file modes which used by git).

Changes:
* "gitweb diff header" which looked for example like below:
    file:_<sha1 before>_ -> file:_<sha1 after>_
  where 'file' is file type and '<sha1>' is full sha1 of blob is
  changed to
    diff --git _a/<file before>_ _b/<file after>_
  In both cases links are visible and use default link style. If file
  is added, a/<file> is not hyperlinked. If file is deleted, b/<file>
  is not hyperlinked.
* there is added "extended diff header", with <path> and <hash>
  hyperlinked (and <hash> shortened to 7 characters), and <mode>
  explained: '<mode>' is extended to '<mode> (<file type description>)',
  where added text is slightly lighter to easy distinguish that it
  was added (and it is difference from git-diff output).
* from-file/to-file two-line header lines have slightly darker color
  than removed/added lines.
* chunk header has now delicate line above for easier finding chunk
  boundary, and top margin of 2px, both barely visible.

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index b80fc60..f937ee1 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -785,6 +785,32 @@
 	}
 }
 
+# convert file mode in octal to file type description string
+sub file_type_long {
+	my $mode = shift;
+
+	if ($mode !~ m/^[0-7]+$/) {
+		return $mode;
+	} else {
+		$mode = oct $mode;
+	}
+
+	if (S_ISDIR($mode & S_IFMT)) {
+		return "directory";
+	} elsif (S_ISLNK($mode)) {
+		return "symlink";
+	} elsif (S_ISREG($mode)) {
+		if ($mode & S_IXUSR) {
+			return "executable";
+		} else {
+			return "file";
+		};
+	} else {
+		return "unknown";
+	}
+}
+
+
 ## ----------------------------------------------------------------------
 ## functions returning short HTML fragments, or transforming HTML fragments
 ## which don't beling to other sections
@@ -2171,6 +2197,7 @@
 	my $in_header = 0;
 	my $patch_found = 0;
 	my $diffinfo;
+	my (%from, %to);
 
 	print "<div class=\"patchset\">\n";
 
@@ -2181,6 +2208,10 @@
 		if ($patch_line =~ m/^diff /) { # "git diff" header
 			# beginning of patch (in patchset)
 			if ($patch_found) {
+				# close extended header for previous empty patch
+				if ($in_header) {
+					print "</div>\n" # class="diff extended_header"
+				}
 				# close previous patch
 				print "</div>\n"; # class="patch"
 			} else {
@@ -2189,89 +2220,113 @@
 			}
 			print "<div class=\"patch\" id=\"patch". ($patch_idx+1) ."\">\n";
 
+			# read and prepare patch information
 			if (ref($difftree->[$patch_idx]) eq "HASH") {
+				# pre-parsed (or generated by hand)
 				$diffinfo = $difftree->[$patch_idx];
 			} else {
 				$diffinfo = parse_difftree_raw_line($difftree->[$patch_idx]);
 			}
+			$from{'file'} = $diffinfo->{'from_file'} || $diffinfo->{'file'};
+			$to{'file'}   = $diffinfo->{'to_file'}   || $diffinfo->{'file'};
+			if ($diffinfo->{'status'} ne "A") { # not new (added) file
+				$from{'href'} = href(action=>"blob", hash_base=>$hash_parent,
+				                     hash=>$diffinfo->{'from_id'},
+				                     file_name=>$from{'file'});
+			}
+			if ($diffinfo->{'status'} ne "D") { # not deleted file
+				$to{'href'} = href(action=>"blob", hash_base=>$hash,
+				                   hash=>$diffinfo->{'to_id'},
+				                   file_name=>$to{'file'});
+			}
 			$patch_idx++;
 
-			if ($diffinfo->{'status'} eq "A") { # added
-				print "<div class=\"diff_info\">" . file_type($diffinfo->{'to_mode'}) . ":" .
-				      $cgi->a({-href => href(action=>"blob", hash_base=>$hash,
-				                             hash=>$diffinfo->{'to_id'}, file_name=>$diffinfo->{'file'})},
-				              $diffinfo->{'to_id'}) . " (new)" .
-				      "</div>\n"; # class="diff_info"
-
-			} elsif ($diffinfo->{'status'} eq "D") { # deleted
-				print "<div class=\"diff_info\">" . file_type($diffinfo->{'from_mode'}) . ":" .
-				      $cgi->a({-href => href(action=>"blob", hash_base=>$hash_parent,
-				                             hash=>$diffinfo->{'from_id'}, file_name=>$diffinfo->{'file'})},
-				              $diffinfo->{'from_id'}) . " (deleted)" .
-				      "</div>\n"; # class="diff_info"
-
-			} elsif ($diffinfo->{'status'} eq "R" || # renamed
-			         $diffinfo->{'status'} eq "C" || # copied
-			         $diffinfo->{'status'} eq "2") { # with two filenames (from git_blobdiff)
-				print "<div class=\"diff_info\">" .
-				      file_type($diffinfo->{'from_mode'}) . ":" .
-				      $cgi->a({-href => href(action=>"blob", hash_base=>$hash_parent,
-				                             hash=>$diffinfo->{'from_id'}, file_name=>$diffinfo->{'from_file'})},
-				              $diffinfo->{'from_id'}) .
-				      " -> " .
-				      file_type($diffinfo->{'to_mode'}) . ":" .
-				      $cgi->a({-href => href(action=>"blob", hash_base=>$hash,
-				                             hash=>$diffinfo->{'to_id'}, file_name=>$diffinfo->{'to_file'})},
-				              $diffinfo->{'to_id'});
-				print "</div>\n"; # class="diff_info"
-
-			} else { # modified, mode changed, ...
-				print "<div class=\"diff_info\">" .
-				      file_type($diffinfo->{'from_mode'}) . ":" .
-				      $cgi->a({-href => href(action=>"blob", hash_base=>$hash_parent,
-				                             hash=>$diffinfo->{'from_id'}, file_name=>$diffinfo->{'file'})},
-				              $diffinfo->{'from_id'}) .
-				      " -> " .
-				      file_type($diffinfo->{'to_mode'}) . ":" .
-				      $cgi->a({-href => href(action=>"blob", hash_base=>$hash,
-				                             hash=>$diffinfo->{'to_id'}, file_name=>$diffinfo->{'file'})},
-				              $diffinfo->{'to_id'});
-				print "</div>\n"; # class="diff_info"
+			# print "git diff" header
+			$patch_line =~ s!^(diff (.*?) )"?a/.*$!$1!;
+			if ($from{'href'}) {
+				$patch_line .= $cgi->a({-href => $from{'href'}, -class => "path"},
+				                       'a/' . esc_path($from{'file'}));
+			} else { # file was added
+				$patch_line .= 'a/' . esc_path($from{'file'});
+			}
+			$patch_line .= ' ';
+			if ($to{'href'}) {
+				$patch_line .= $cgi->a({-href => $to{'href'}, -class => "path"},
+				                       'b/' . esc_path($to{'file'}));
+			} else { # file was deleted
+				$patch_line .= 'b/' . esc_path($to{'file'});
 			}
 
-			#print "<div class=\"diff extended_header\">\n";
+			print "<div class=\"diff header\">$patch_line</div>\n";
+			print "<div class=\"diff extended_header\">\n";
 			$in_header = 1;
 			next LINE;
-		} # start of patch in patchset
+		}
 
+		if ($in_header) {
+			if ($patch_line !~ m/^---/) {
+				# match <path>
+				if ($patch_line =~ s!^((copy|rename) from ).*$!$1! && $from{'href'}) {
+					$patch_line .= $cgi->a({-href=>$from{'href'}, -class=>"path"},
+					                        esc_path($from{'file'}));
+				}
+				if ($patch_line =~ s!^((copy|rename) to ).*$!$1! && $to{'href'}) {
+					$patch_line = $cgi->a({-href=>$to{'href'}, -class=>"path"},
+					                      esc_path($to{'file'}));
+				}
+				# match <mode>
+				if ($patch_line =~ m/\s(\d{6})$/) {
+					$patch_line .= '<span class="info"> (' .
+					               file_type_long($1) .
+					               ')</span>';
+				}
+				# match <hash>
+				if ($patch_line =~ m/^index/) {
+					my ($from_link, $to_link);
+					if ($from{'href'}) {
+						$from_link = $cgi->a({-href=>$from{'href'}, -class=>"hash"},
+						                     substr($diffinfo->{'from_id'},0,7));
+					} else {
+						$from_link = '0' x 7;
+					}
+					if ($to{'href'}) {
+						$to_link = $cgi->a({-href=>$to{'href'}, -class=>"hash"},
+						                   substr($diffinfo->{'to_id'},0,7));
+					} else {
+						$to_link = '0' x 7;
+					}
+					my ($from_id, $to_id) = ($diffinfo->{'from_id'}, $diffinfo->{'to_id'});
+					$patch_line =~ s!$from_id\.\.$to_id!$from_link..$to_link!;
+				}
+				print $patch_line . "<br/>\n";
 
-		if ($in_header && $patch_line =~ m/^---/) {
-			#print "</div>\n"; # class="diff extended_header"
-			$in_header = 0;
+			} else {
+				#$in_header && $patch_line =~ m/^---/;
+				print "</div>\n"; # class="diff extended_header"
+				$in_header = 0;
 
-			my $file = $diffinfo->{'from_file'};
-			$file  ||= $diffinfo->{'file'};
-			$file = $cgi->a({-href => href(action=>"blob", hash_base=>$hash_parent,
-			                               hash=>$diffinfo->{'from_id'}, file_name=>$file),
-			                -class => "list"}, esc_path($file));
-			$patch_line =~ s|a/.*$|a/$file|g;
-			print "<div class=\"diff from_file\">$patch_line</div>\n";
+				if ($from{'href'}) {
+					$patch_line = '--- a/' .
+					              $cgi->a({-href=>$from{'href'}, -class=>"path"},
+					                      esc_path($from{'file'}));
+				}
+				print "<div class=\"diff from_file\">$patch_line</div>\n";
 
-			$patch_line = <$fd>;
-			chomp $patch_line;
+				$patch_line = <$fd>;
+				chomp $patch_line;
 
-			#$patch_line =~ m/^+++/;
-			$file    = $diffinfo->{'to_file'};
-			$file  ||= $diffinfo->{'file'};
-			$file = $cgi->a({-href => href(action=>"blob", hash_base=>$hash,
-			                               hash=>$diffinfo->{'to_id'}, file_name=>$file),
-			                -class => "list"}, esc_path($file));
-			$patch_line =~ s|b/.*|b/$file|g;
-			print "<div class=\"diff to_file\">$patch_line</div>\n";
+				#$patch_line =~ m/^+++/;
+				if ($to{'href'}) {
+					$patch_line = '+++ b/' .
+					              $cgi->a({-href=>$to{'href'}, -class=>"path"},
+					                      esc_path($to{'file'}));
+				}
+				print "<div class=\"diff to_file\">$patch_line</div>\n";
+
+			}
 
 			next LINE;
 		}
-		next LINE if $in_header;
 
 		print format_diff_line($patch_line);
 	}