[PATCH 4/5] Let git-add--interactive read colors from configuration

[Dan Zwell <dzwell@zwell.net>]

Colors are specified in color.interactive.{prompt,header,help}.
They are specified as git color strings as described in the
documentation. The method color_to_ansi_code() in Git.pm parses
these strings and returns ANSI color codes (using
Term::ANSIColor).

Signed-off-by: Dan Zwell <dzwell@zwell.net>
---
 Documentation/config.txt  |    7 ++++
 git-add--interactive.perl |   20 ++++++++---
 perl/Git.pm               |   80 ++++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 100 insertions(+), 7 deletions(-)

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 3712d6a..47c1ab2 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -388,6 +388,13 @@ color.interactive::
 	`auto`, use colors only when the output is to the
 	terminal. Defaults to false.
 
+color.interactive.<slot>::
+	Use customized color for `git add --interactive`
+	output. `<slot>` may be `prompt`, `header`, or `help`, for
+	three distinct types of normal output from interactive
+	programs.  The values of these variables may be specified as
+	in color.branch.<slot>.
+
 color.pager::
 	A boolean to enable/disable colored output when the pager is in
 	use (default is true).
diff --git a/git-add--interactive.perl b/git-add--interactive.perl
index 2b5559f..f76f008 100755
--- a/git-add--interactive.perl
+++ b/git-add--interactive.perl
@@ -6,8 +6,8 @@ use Git;
 my ($use_color, $prompt_color, $header_color, $help_color, $normal_color);
 
 {
-	# set color options:
 	my $repo = Git->repository();
+	# set interactive color options:
 	my $color_config = $repo->config('color.interactive');
 	$use_color = 0;
 	if (!defined $color_config) {
@@ -28,11 +28,19 @@ my ($use_color, $prompt_color, $header_color, $help_color, $normal_color);
 			$use_color = 0;
 		}
 		else { # set up colors
-			# Sane (visible) defaults:
-			$prompt_color = Term::ANSIColor::color('blue bold');
-			$header_color = Term::ANSIColor::color('bold');
-			$help_color   = Term::ANSIColor::color('red bold');
-			$normal_color = Term::ANSIColor::color('reset');
+			# Grab the 3 main colors in git color string format, with sane
+			# (visible) defaults:
+			$prompt_color = Git::color_to_ansi_code(
+				scalar $repo->config_default('color.interactive.prompt',
+					'bold blue'));
+			$header_color = Git::color_to_ansi_code(
+				scalar $repo->config_default('color.interactive.header',
+					'bold'));
+			$help_color = Git::color_to_ansi_code(
+				scalar $repo->config_default('color.interactive.help',
+					'red bold'));
+
+			$normal_color = Git::color_to_ansi_code('normal');
 		}
 	}
 }
diff --git a/perl/Git.pm b/perl/Git.pm
index 7327300..18ef6b4 100644
--- a/perl/Git.pm
+++ b/perl/Git.pm
@@ -515,7 +515,6 @@ sub config {
 	};
 }
 
-
 =item config_bool ( VARIABLE )
 
 Retrieve the bool configuration C<VARIABLE>. The return value
@@ -578,6 +577,85 @@ sub config_default {
 	}
 }
 
+=item color_to_ansi_code ( COLOR )
+
+Converts a git-style color string, like "underline blue white" to
+an ANSI color code. The code is generated by Term::ANSIColor,
+after the string is parsed into the format that is accepted by
+that module. Used as follows:
+
+	print color_to_ansi_code("underline blue white");
+	print "some text";
+	print color_to_ansi_code("normal");
+
+color_to_ansi_code('') returns the empty string, and should do
+nothing when printed.
+
+=cut
+
+sub color_to_ansi_code {
+	my ($git_string) = @_;
+	my @ansi_words;
+	my %git_to_perl_color = (
+		'bold'    => 'bold',
+		'ul'      => 'underline',
+		'blink'   => 'blink',
+		'reverse' => 'reverse'
+		# not supported by Term::ANSIColor:
+		#'dim'     => ''
+	);
+	my %valid_color = map { $_ => 1 } qw(black red green yellow
+					    blue magenta cyan white);
+
+	my ($fg_done, $token);
+	foreach $token (split /\s+/, $git_string) {
+		$token = lc($token);
+
+		if ($token eq 'normal') {
+			$fg_done = 1;
+		}
+		elsif (exists $valid_color{$token}) {
+			# is a color.
+			if ($fg_done) {
+				# this is the background
+				push @ansi_words, 'on_' . $token;
+			}
+			else {
+				# this is foreground
+				$fg_done = 1;
+				push @ansi_words, $token;
+			}
+		}
+		else {
+			# this is an attribute, not a color.
+			if ($git_to_perl_color{$token}) {
+				push(@ansi_words,
+					 $git_to_perl_color{$token});
+			}
+			else {
+				print STDERR 'Warning: bad color or attribute: ';
+				print STDERR "\"$token\". Check git configuration.\n";
+			}
+		}
+	}
+
+	# decide what to return--return color codes, 'clear' code, or
+	# the empty string, depending on the input we were passed /
+	# what we have processed:
+	if (@ansi_words) {
+		return Term::ANSIColor::color(join(' ', @ansi_words));
+	}
+	else {
+		if ($fg_done) {
+			# the git attrib 'normal' was processed
+			return Term::ANSIColor::color('clear');
+		}
+		else {
+			return '';
+		}
+	}
+}
+
 =item ident ( TYPE | IDENTSTR )
 
 =item ident_person ( TYPE | IDENTSTR | IDENTARRAY )
-- 
1.5.3.5.565.gf0b83-dirty