# -*- coding: utf-8 -*-

"""

    rhodecode.lib.indexers.daemon

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    A daemon will read from task table and run tasks

    :created_on: Jan 26, 2010

    :author: marcink

    :copyright: (C) 2010-2012 Marcin Kuzminski <marcin@python-works.com>

    :license: GPLv3, see COPYING for more details.

"""

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import os

import sys

import logging

import traceback

from shutil import rmtree

from time import mktime

from os.path import dirname as dn

from os.path import join as jn

#to get the rhodecode import

project_path = dn(dn(dn(dn(os.path.realpath(__file__)))))

sys.path.append(project_path)

from rhodecode.model.scm import ScmModel

from rhodecode.lib import safe_unicode

from rhodecode.lib.indexers import INDEX_EXTENSIONS, SCHEMA, IDX_NAME

from rhodecode.lib.vcs.exceptions import ChangesetError, RepositoryError, \

    NodeDoesNotExistError

from whoosh.index import create_in, open_dir

class WhooshIndexingDaemon(object):

    """

    Daemon for atomic jobs

    """

    def __init__(self, indexname=IDX_NAME, index_location=None,

                 repo_location=None, sa=None, repo_list=None):

        self.indexname = indexname

        self.index_location = index_location

        if not index_location:

            raise Exception('You have to provide index location')

        self.repo_location = repo_location

        if not repo_location:

            raise Exception('You have to provide repositories location')

        self.repo_paths = ScmModel(sa).repo_scan(self.repo_location)

        if repo_list:

            filtered_repo_paths = {}

            for repo_name, repo in self.repo_paths.items():

                if repo_name in repo_list:

                    filtered_repo_paths[repo_name] = repo

            self.repo_paths = filtered_repo_paths

        self.initial = False

        if not os.path.isdir(self.index_location):

            os.makedirs(self.index_location)

            log.info('Cannot run incremental index since it does not'

                     ' yet exist running full build')

            self.initial = True

    def get_paths(self, repo):

        based on repository walk function

        """

        index_paths_ = set()

        try:

            tip = repo.get_changeset('tip')

            for topnode, dirs, files in tip.walk('/'):

                for f in files:

                    index_paths_.add(jn(repo.path, f.path))

        except RepositoryError, e:

            log.debug(traceback.format_exc())

            pass

        return index_paths_

    def get_node(self, repo, path):

        n_path = path[len(repo.path) + 1:]

        node = repo.get_changeset().get_node(n_path)

        return node

    def get_node_mtime(self, node):

        return mktime(node.last_changeset.date.timetuple())

    def add_doc(self, writer, path, repo, repo_name):

        node = self.get_node(repo, path)

        if node.extension in INDEX_EXTENSIONS and not node.is_binary:

            u_content = node.content

            if not isinstance(u_content, unicode):

                log.warning('  >> %s Could not get this content as unicode '

                u_content = u''

            else:

                log.debug('    >> %s [WITH CONTENT]' % path)

        else:

            log.debug('    >> %s' % path)

            u_content = u''

    def build_index(self):

        if os.path.exists(self.index_location):

            log.debug('removing previous index')

            rmtree(self.index_location)

        if not os.path.exists(self.index_location):

            os.mkdir(self.index_location)

        idx = create_in(self.index_location, SCHEMA, indexname=IDX_NAME)

        writer = idx.writer()

        for repo_name, repo in self.repo_paths.items():

            log.debug('building index @ %s' % repo.path)

            for idx_path in self.get_paths(repo):

                self.add_doc(writer, idx_path, repo, repo_name)

        log.debug('>> COMMITING CHANGES <<')

        writer.commit(merge=True)

        log.debug('>>> FINISHED BUILDING INDEX <<<')

    def update_index(self):

        log.debug('STARTING INCREMENTAL INDEXING UPDATE')

        idx = open_dir(self.index_location, indexname=self.indexname)

        # The set of all paths in the index

        indexed_paths = set()

        # The set of all paths we need to re-index

        to_index = set()

        reader = idx.reader()

        writer = idx.writer()

        # Loop over the stored fields in the index

        for fields in reader.all_stored_fields():

            indexed_path = fields['path']

            indexed_paths.add(indexed_path)

            repo = self.repo_paths[fields['repository']]

            try:

                node = self.get_node(repo, indexed_path)

            except (ChangesetError, NodeDoesNotExistError):

                # This file was deleted since it was indexed

                log.debug('removing from index %s' % indexed_path)

                writer.delete_by_term('path', indexed_path)

            else:

                # Check if this file was changed since it was indexed

                indexed_time = fields['modtime']

                mtime = self.get_node_mtime(node)

                if mtime > indexed_time:

                    # The file has changed, delete it and add it to the list of

                    # files to reindex

                    log.debug('adding to reindex list %s' % indexed_path)

                    writer.delete_by_term('path', indexed_path)

                    to_index.add(indexed_path)

        # Loop over the files in the filesystem

        # Assume we have a function that gathers the filenames of the

        # documents to be indexed

        for repo_name, repo in self.repo_paths.items():

            for path in self.get_paths(repo):

                if path in to_index or path not in indexed_paths:

                    # This is either a file that's changed, or a new file

                    # that wasn't indexed before. So index it!

                    self.add_doc(writer, path, repo, repo_name)

                    log.debug('re indexing %s' % path)

        log.debug('>> COMMITING CHANGES <<')

        writer.commit(merge=True)

        log.debug('>>> FINISHED REBUILDING INDEX <<<')

    def run(self, full_index=False):

        """Run daemon"""

        if full_index or self.initial:

            self.build_index()

        else:

            self.update_index()