#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 1/26/04 (Mon)
#    I made some assumption on cgi program character coding.
#    - *.html files should be in iso-2022-jp
#    - *.cgi files should be in euc-jp
#    - http output in iso-2022-jp.
#    This may cause a difficulty when I try to devise a cgi tool
#    that handle the html files.  Hmmmm
# 2/1/04 (Sun) 1.0 released.
# 2/6/04 (Fri) 1.01 exception for <a name="TOC"> included
# 4/1/04 (Thu) 1.02 removed exception, change order of menu, added home.
# 4/4/04 (Sun) 1.03 removed most of the redundant variables
#              relaxed the requirement for being heading
# 2007-04-28 (Sat): 1.04 japanese.iso- => .iso-
# 2007-04-28 (Sat): 1.05 insert "search" to navi menu div
# 2010-03-20 (Sat): utf-8 output

import sys, re, string, datetime
#CODING = "euc-jp"
CODING = "utf-8"
def main(argv):
    try:
        fs = open(argv[1])
    except IOError:
        print "Can't open '" + argv[1] + "'"
        sys.exit(1)
    lines = fs.readlines()
    fs.close()
    try:
        fd = open("conversion.log", "a")
    except IOError:
        print "Can't open 'conversion_log'"
        sys.exit(1)

    fd.write("\n%s: %s\n" % (datetime.date.today().isoformat(), argv[1]))

    # strip the old nav bars
    anchors = []
    nonav_lines = []
    navi_start = re.compile('<div\s*class\s*=\s*"navbar"')
    navi_end = re.compile('</div>')
    in_navi = False
    s_encode = 'utf-8'
    for line in lines:
        if re.search('<[^>]*charset\s?=\s?euc-jp\s?"\s?>', line):
            line = line.replace('euc-jp', 'utf-8')
            s_encode = 'euc-jp'
        if re.search('<link [^>]* href="style/default_u.css".*>', line):
            line = line.replace('default_u.css', 'default.css')
            fd.write("default_u to default")
            
        if re.search('<!--\s*#include\s+virtual\s?=\s?"menu_div_u.html".*-->'
                     , line):
            line = line.replace('menu_div_u.html', 'menu_div.html')
        try:
            uline = unicode(line, s_encode) ## 2007-09-23 (Sun):
        except UnicodeDecodeError:
            fd.write('DecodeError: in "%s"\n' % line)
            fd.close()
            sys.exit(1)
        if navi_start.search(uline):
            in_navi = True
        if in_navi:
            if navi_end.search(uline):
                in_navi = False
        else: # 4/4/04 (Sun) remove succeeding blank lines
            if len(uline) <= 1 and len(nonav_lines[-1]) <= 1:
                continue
            else:
                nonav_lines.append(uline)
    fd.write("coding was '%s', and being converted to utf-8\n" % s_encode)
    anch_patt = re.compile('<a\s*name\s*=\s*"(\S+)"\s*>\s*</a>')
    # 4/4/04 (Sun) relaxed <h3> to <h3 xxx>
#   subj_patt = re.compile('<[Hh]3\s*.*>\s*(.*)\s*</[Hh]3>', re.DOTALL)
    subj_start = re.compile('<[Hh][23]\s*.*>')
    subj_end = re.compile('</[Hh][23]>')
    in_subj = False
    anchors = []
    anchor = ""
    for uline in nonav_lines:
        anch_ob = anch_patt.search(uline)
        if anch_ob: # if <a name="xxx"></a> found
            anchor = anch_ob.group(1)
#           anchors.append(anchor)
            continue
        if subj_start.search(uline):
            in_subj = True
        if in_subj:
            #   subjlines += uline
            # modified to ignore consecutive headings 4/4/04 (Sun)
            if subj_end.search(uline):
                if len(anchor) >= 1:
                    anchors.append(anchor)
                in_subj = False
                anchor = ""
                
    nav_form_bak =\
u'''<div class="navbar">
  [<a href="#%s">↓次</a> <a href="#%s">↑前</a> <a href="#TOC">目次</a>
  <a href="index.html">Home</a> 
<a href="/cgi-bin/snamazu.cgi">検索</a>]</div>\n'''

    nav_form = u'''<div class="navbar">
  (<a href="#%s">↓次</a> <a href="#%s">↑前</a> <a href="#TOC">目次</a>
  <a href="index.html">Home</a>)</div>\n'''
    anchlen = len(anchors)
    results = []

    # insert navigation bar before ???
    for line in nonav_lines:
        
        sys.stdout.write(line.encode(CODING))
        anchor = anch_patt.search(line)
        if anchor:
            anchor_key = anchor.group(1)
            sys.stderr.write(anchor_key + "\n") ##
            try:
                ia = anchors.index(anchor_key)
            except ValueError:
                sys.stderr.write(anchor_key + "\n") ##
                # if there is no corresponding <H3>, no navigator is put
                continue
            
            navbar = nav_form % \
                     (anchors[(ia + 1) % anchlen], anchors[ia - 1])
            sys.stdout.write( navbar.encode(CODING) )
    fd.close()
if __name__ == "__main__":
    main(sys.argv)