[PATCH 2/3] Move decision which files to handle into chunkers

[Michael Hanselmann]

This makes the code more flexible and makes it easier to add more
chunkers.
---
 lib/Brackup/Chunker/Default.pm |    7 +++++++
 lib/Brackup/Chunker/MP3.pm     |   15 ++++++++++-----
 lib/Brackup/File.pm            |   25 +++++++++++++++++++------
 3 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/lib/Brackup/Chunker/Default.pm b/lib/Brackup/Chunker/Default.pm
index a661f21..a4691ff 100644
--- a/lib/Brackup/Chunker/Default.pm
+++ b/lib/Brackup/Chunker/Default.pm
@@ -2,6 +2,13 @@ package Brackup::Chunker::Default;
 use strict;
 use warnings;
 
+sub handles {
+     my ($class, $file) = @_;
+
+    # This is the default chunker. It handles every file type.
+    return 1;
+}
+
 sub get_offsets {
     my ($class, $file, $cb) = @_;
 
diff --git a/lib/Brackup/Chunker/MP3.pm b/lib/Brackup/Chunker/MP3.pm
index fe5cf46..4943003 100644
--- a/lib/Brackup/Chunker/MP3.pm
+++ b/lib/Brackup/Chunker/MP3.pm
@@ -7,6 +7,15 @@ BEGIN {
     $HAVE_MP3_INFO = eval "use MP3::Info (); 1;";
 }
 
+sub handles {
+     my ($class, $file) = @_;
+
+    return 0 unless $file->root->smart_mp3_chunking;
+
+    # Only handle MP3 files
+    return $file->path =~ m/\.mp3$/i;
+}
+
 sub get_offsets {
     my ($class, $file, $cb) = @_;
 
@@ -41,13 +50,9 @@ sub main_music_range {
     my ($file) = @_;
     my $size = $file->size;
 
-    # if not an mp3, include the whole file
-    unless ($file =~ /\.mp3$/i) {
-        return (0, $size);
-    }
-
     my $info = MP3::Info::get_mp3info($file);
     unless ($info && defined $info->{OFFSET}) {
+        # TODO: call default chunker
         return (0, $size);
     }
 
diff --git a/lib/Brackup/File.pm b/lib/Brackup/File.pm
index 8dc2ee9..827eff1 100644
--- a/lib/Brackup/File.pm
+++ b/lib/Brackup/File.pm
@@ -12,6 +12,11 @@ use Brackup::PositionedChunk;
 use Brackup::Chunker::Default;
 use Brackup::Chunker::MP3;
 
+my @chunkers = (
+    'Brackup::Chunker::MP3',
+    'Brackup::Chunker::Default',
+);
+
 sub new {
     my ($class, %opts) = @_;
     my $self = bless {}, $class;
@@ -99,12 +104,17 @@ sub cachekey {
 # into its own small chunks).  This way the mp3 metadata can be
 # changed without needing to back up the entire file again ... just
 # the changed metadata.
-sub file_chunker {
+sub find_file_chunker {
     my $self = shift;
-    if ($self->{path} =~ /\.mp3$/i && $self->{root}->smart_mp3_chunking) {
-        return "Brackup::Chunker::MP3";
-    }
-    return "Brackup::Chunker::Default";
+
+    # Try to find chunker
+    foreach (@chunkers) {
+        if ($_->handles($self)) {
+            return $_;
+        }
+     }
+
+    die "No chunker found";
 }
 
 sub chunks {
@@ -122,11 +132,14 @@ sub chunks {
     # then pass ourselves to it to get our chunks.
     my @chunk_list;
 
+    # Get the appropriate FileChunker for this file type
+    my $chunker = $self->find_file_chunker();
+
     my $size = $self->size;
     my $last_offset = undef;
     my $last_len = undef;
 
-    $self->file_chunker->get_offsets($self, sub {
+    $chunker->get_offsets($self, sub {
         my ($offset, $len) = @_;
 
         # Lots of verification on offset and length
-- 
1.5.5.3