From 78339374d8e5f168b1492ea2d0abdf06746faeb8 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 30 Apr 2010 08:48:20 -0600
Subject: [PATCH] Nicer error message when user tries to convert/view a Topaz
 book with a .prc extension

---
 src/calibre/ebooks/mobi/reader.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/calibre/ebooks/mobi/reader.py b/src/calibre/ebooks/mobi/reader.py
index c5f134c8d9..e18a95dd2d 100644
--- a/src/calibre/ebooks/mobi/reader.py
+++ b/src/calibre/ebooks/mobi/reader.py
@@ -254,6 +254,8 @@ class MobiReader(object):
             stream = open(filename_or_stream, 'rb')
 
         raw = stream.read()
+        if raw.startswith('TPZ'):
+            raise ValueError(_('This is an Amazon Topaz book. It cannot be processed.'))
 
         self.header   = raw[0:72]
         self.name     = self.header[:32].replace('\x00', '')
@@ -261,7 +263,7 @@ class MobiReader(object):
 
         self.ident = self.header[0x3C:0x3C + 8].upper()
         if self.ident not in ['BOOKMOBI', 'TEXTREAD']:
-            raise MobiError('Unknown book type: %s' % self.ident)
+            raise MobiError('Unknown book type: %s' % repr(self.ident))
 
         self.sections = []
         self.section_headers = []