From 0479f31a5f072a8c02661c373391eaf498dc1209 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sat, 17 Mar 2012 23:14:55 +0530
Subject: [PATCH] KF8 Input: Fix some links pointing a little above or below
 their intended target when viewing or converting KF8 files

---
 src/calibre/ebooks/mobi/reader/markup.py |  3 ++-
 src/calibre/ebooks/mobi/reader/mobi8.py  | 28 ++++++++++++++----------
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/calibre/ebooks/mobi/reader/markup.py b/src/calibre/ebooks/mobi/reader/markup.py
index 721de28ff4..8bb7f211f3 100644
--- a/src/calibre/ebooks/mobi/reader/markup.py
+++ b/src/calibre/ebooks/mobi/reader/markup.py
@@ -36,7 +36,8 @@ def update_internal_links(mobi8_reader):
                     filename, idtag = mr.get_id_tag_by_pos_fid(int(posfid, 32),
                             int(offset, 32))
                     suffix = (b'#' + idtag) if idtag else b''
-                    replacement = filename.encode(mr.header.codec) + suffix
+                    replacement = filename.split('/')[-1].encode(
+                            mr.header.codec) + suffix
                     tag = posfid_index_pattern.sub(replacement, tag, 1)
                 srcpieces[j] = tag
         part = ''.join([x.decode(mr.header.codec) for x in srcpieces])
diff --git a/src/calibre/ebooks/mobi/reader/mobi8.py b/src/calibre/ebooks/mobi/reader/mobi8.py
index 5105e20f0b..ec7166ebb0 100644
--- a/src/calibre/ebooks/mobi/reader/mobi8.py
+++ b/src/calibre/ebooks/mobi/reader/mobi8.py
@@ -233,7 +233,6 @@ class Mobi8Reader(object):
         insertpos, idtext, filenum, seqnm, startpos, length = self.elems[posfid]
         pos = insertpos + offset
         fi = self.get_file_info(pos)
-        fname = fi.filename
         # an existing "id=" must exist in original xhtml otherwise it would not
         # have worked for linking.  Amazon seems to have added its own
         # additional "aid=" inside tags whose contents seem to represent some
@@ -242,7 +241,7 @@ class Mobi8Reader(object):
         # so find the closest "id=" before position the file by actually
         # searching in that file
         idtext = self.get_id_tag(pos)
-        return fname, idtext
+        return '%s/%s'%(fi.type, fi.filename), idtext
 
     def get_id_tag(self, pos):
         # find the correct tag by actually searching in the destination
@@ -253,12 +252,13 @@ class Mobi8Reader(object):
         textblock = self.parts[fi.num]
         id_map = []
         npos = pos - fi.start
-        # if npos inside a tag then search all text before the its end of tag
-        # marker
         pgt = textblock.find(b'>', npos)
         plt = textblock.find(b'<', npos)
-        if pgt < plt:
+        # if npos inside a tag then search all text before the its end of tag marker
+        # else not in a tag need to search the preceding tag
+        if plt == npos or pgt < plt:
             npos = pgt + 1
+        textblock = textblock[0:npos]
         # find id links only inside of tags
         #    inside any < > pair find all "id=' and return whatever is inside
         #    the quotes
@@ -315,12 +315,18 @@ class Mobi8Reader(object):
 
         # Add href and anchor info to the index entries
         for entry in index_entries:
-            pos = entry['pos']
-            fi = self.get_file_info(pos)
-            if fi.filename is None:
-                raise ValueError('Index entry has invalid pos: %d'%pos)
-            idtag = self.get_id_tag(pos).decode(self.header.codec)
-            entry['href'] = '%s/%s'%(fi.type, fi.filename)
+            pos_fid = entry['pos_fid']
+            if pos_fid is None:
+                pos = entry['pos']
+                fi = self.get_file_info(pos)
+                if fi.filename is None:
+                    raise ValueError('Index entry has invalid pos: %d'%pos)
+                idtag = self.get_id_tag(pos).decode(self.header.codec)
+                href = '%s/%s'%(fi.type, fi.filename)
+            else:
+                href, idtag = self.get_id_tag_by_pos_fid(*pos_fid)
+
+            entry['href'] = href
             entry['idtag'] = idtag
 
         # Build the TOC object