#! /usr/bin/python
from trac.core import *
from trac.env import *

import sys
import sre
import os
import time
import optparse
import urllib

__all__ = ['main', 'rename_page']

def pass_(*args): 
    pass
    
def print_(s, *args): 
    print s%args
    
def log_intercept(log):
    def out(s, *args):
        log('WikiRenamePlugin: '+s, *args)
    return out

def rename_page(env, oldname, newname, user, ip, debug=False, db=None):
    """Rename a wiki page from oldname to newname, using env as the environment."""
    handle_commit = False
    if not db:
        db = env.get_db_cnx()
        handle_commit = True
    cursor = db.cursor()
    
    if debug is False:
        debug = pass_
    elif debug is True:
        debug = print_
    else:
        debug = log_intercept(debug)

    sqlbase = ' FROM wiki w1, ' + \
        '(SELECT name, MAX(version) AS max_version FROM wiki GROUP BY name) w2 ' + \
        'WHERE w1.version = w2.max_version AND w1.name = w2.name '

    sql = 'SELECT w1.version,w1.text' + sqlbase + 'AND w1.name = \'%s\'' % oldname
    debug('Running query %r', sql)
    cursor.execute(sql)

    row = cursor.fetchone()

    if not row:
        raise TracError, 'Page not found'
    
    new_wiki_page = (newname,row[0]+1,int(time.time()),user,ip,row[1],'Name changed from %s to %s'%(oldname,newname),0)

    # Create a new page with the needed comment
    debug('Inserting new page %r', new_wiki_page)
    cursor.execute('INSERT INTO wiki (name,version,time,author,ipnr,text,comment,readonly) VALUES (%s,%s,%s,%s,%s,%s,%s,%s)', new_wiki_page)

    # Move all the old versions of the page
    debug("Moving all old versions of page")
    cursor.execute('UPDATE wiki SET name=%s WHERE name=%s', (newname,oldname))

    # Move any attachments that are on the page
    debug("Moving all attachments in database")
    cursor.execute('UPDATE attachment SET id=%s WHERE type=%s AND id=%s', (newname,'wiki',oldname))

    debug("Found %s attachments on that page", cursor.rowcount)
    if cursor.rowcount > 0:
        # Change the directory where the attachments are stored, if there were any
        debug('Moving all attachments on file system')
        from_path = os.path.join(env.path, 'attachments', 'wiki', urllib.quote(oldname))
        to_path = os.path.join(env.path, 'attachments', 'wiki', urllib.quote(newname))
        debug('Moving from %r to %r', from_path, to_path)
        os.renames(from_path, to_path)

    # Get a list of all wiki pages containing links to the old page
    debug("Trying to fix links")
    sql = 'SELECT w1.version,w1.name,w1.text' + sqlbase + "AND w1.text like '%%[wiki:%s%%'" % oldname
    debug('Running query %r', sql)
    cursor.execute(sql)

    # Rewrite all links to the old page, such as to point to the new page
    for row in list(cursor):
        debug("Found a page with a backlink in it: %s (v%s)", row[1], row[0])
        newtext = sre.sub('\[wiki:%s'%oldname,'[wiki:%s'%newname,row[2])
        cursor.execute('UPDATE wiki SET text=%s WHERE name=%s AND version=%s', (newtext,row[1],row[0]))

    if handle_commit:
        db.commit()