Better handling of boundary conditions

Trying with serialport.readpartial

app/helpers/ConfirmingSyncPatternState.rb

@@ -5,7 +5,7 @@ class ConfirmingSyncPatternState < StatePattern::State
    sync_length = Synchronizer::SYNC_PATTERN.length
    
    # confirm rest of sync pattern 
-   while ((idx < sync_length) && bytes[idx] == Synchronizer::SYNC_PATTERN[idx]) do idx = idx+1 end
+   while (idx < bytes.length && idx < sync_length && bytes[idx] == Synchronizer::SYNC_PATTERN[idx]) do idx = idx+1 end
    
    if (idx == sync_length)
      #p "Sync pattern confirmed"

app/helpers/InSyncState.rb

@@ -1,18 +1,35 @@
 class InSyncState < StatePattern::State
   
-  END_OF_FRAME = "!\n"
+ # END_OF_FRAME = "!\n"
 
   def handle_byte_stream(bytes)
     idx = 0
+    sync_pattern_length = Synchronizer::SYNC_PATTERN.length
+    #p "Sync length: #{sync_length}"
+      
     frame = ""
-    while (idx < bytes.length && bytes[idx] != END_OF_FRAME[0]) do
+
+    while (idx+sync_pattern_length < bytes.length && !new_frame_starts(bytes,idx,sync_pattern_length)) do
       frame = frame + bytes[idx]
       idx = idx +1
+      
     end
-    p "------ FRAME -----"
-    frame_lines = frame.split("\n")
-    p frame_lines # should call to higher level
-    p "##################"
-    return ""
+        
+    # did we reach the end of the frame?
+    if new_frame_starts(bytes,idx,sync_pattern_length)
+      p "------ FRAME -----"
+      frame_lines = frame.split("\n")
+      p frame_lines # should call to higher level
+      p "##################"
+      return bytes[idx+sync_pattern_length..-1]
+    else
+      return nil      
+    end
+
   end
+  
+  private
+     def new_frame_starts(bytes,idx,sync_pattern_length)
+       return bytes[idx..idx+sync_pattern_length-1].eql?(Synchronizer::SYNC_PATTERN)
+     end
 end

app/helpers/SearchingForSyncState.rb

@@ -2,7 +2,7 @@ class SearchingForSyncState < StatePattern::State
   def handle_byte_stream(bytes)
    idx = 0;
    # spool unwanted bytes
-   while (bytes[idx] != Synchronizer::SYNC_PATTERN[0]) do idx = idx+1 end
+   while (idx < bytes.length && bytes[idx] != Synchronizer::SYNC_PATTERN[0]) do idx = idx+1 end
    
    #p "Found pattern at idx = #{idx}"
    transition_to(ConfirmingSyncPatternState)