#!/usr/bin/env python3

import logging
import os
from datetime import datetime, timedelta
import shutil

from lookyloo.default import AbstractManager
from lookyloo.exceptions import MissingUUID, NoValidHarFile
from lookyloo.lookyloo import Lookyloo

logging.basicConfig(format='%(asctime)s %(name)s %(levelname)s:%(message)s',
                    level=logging.INFO)


class BackgroundIndexer(AbstractManager):

    def __init__(self, loglevel: int=logging.INFO):
        super().__init__(loglevel)
        self.lookyloo = Lookyloo()
        self.script_name = 'background_indexer'
        # make sure discarded captures dir exists
        self.discarded_captures_dir = self.lookyloo.capture_dir.parent / 'discarded_captures'
        self.discarded_captures_dir.mkdir(parents=True, exist_ok=True)

    def _to_run_forever(self):
        self._build_missing_pickles()
        self._check_indexes()
        self.lookyloo.update_tree_cache_info(os.getpid(), self.script_name)

    def _build_missing_pickles(self):
        for uuid_path in sorted(self.lookyloo.capture_dir.glob('**/uuid'), reverse=True):
            if ((uuid_path.parent / 'tree.pickle').exists()
                    or not list(uuid_path.parent.rglob('*.har'))
                    or not list(uuid_path.parent.rglob('*.har.gz'))):
                continue
            lock_file = uuid_path.parent / 'lock'
            if lock_file.exists():
                try:
                    with lock_file.open('r') as f:
                        lock_ts = datetime.fromisoformat(f.read())
                    if lock_ts < datetime.now() - timedelta(minutes=5):
                        # Clear old locks. They shouldn't be there, but it's gonna happen.
                        self.logger.info(f'Old lock found {lock_file}, removing it.')
                        lock_file.unlink(missing_ok=True)
                except Exception as e:
                    self.logger.info(f'Error while reading lock {lock_file}: {e}')
                continue

            with uuid_path.open() as f:
                uuid = f.read()
            if not self.lookyloo.redis.hexists('lookup_dirs', uuid):
                # The capture with this UUID exists, but it is for some reason missing in lookup_dirs
                self.lookyloo.redis.hset('lookup_dirs', uuid, str(uuid_path.parent))

            try:
                self.logger.info(f'Build pickle for {uuid}: {uuid_path.parent.name}')
                self.lookyloo.get_crawled_tree(uuid)
                self.lookyloo.trigger_modules(uuid, auto_trigger=True)
                self.logger.info(f'Pickle for {uuid} build.')
            except MissingUUID:
                self.logger.warning(f'Unable to find {uuid}. That should not happen.')
            except NoValidHarFile as e:
                self.logger.critical(f'There are no HAR files in the capture {uuid}: {uuid_path.parent.name} - {e}')
            except Exception as e:
                self.logger.critical(f'Unable to build pickle for {uuid}: {uuid_path.parent.name} - {e}')
                # The capture is not working, moving it away.
                self.lookyloo.redis.hdel('lookup_dirs', uuid)
                shutil.move(str(uuid_path.parent), str(self.discarded_captures_dir / uuid_path.parent.name))

    def _check_indexes(self):
        index_redis = self.lookyloo.indexing.redis
        for cache in self.lookyloo.sorted_capture_cache(cached_captures_only=False):
            if self.lookyloo.is_public_instance and cache.no_index:
                # Capture unindexed
                continue
            p = index_redis.pipeline()
            p.sismember('indexed_urls', cache.uuid)
            p.sismember('indexed_body_hashes', cache.uuid)
            p.sismember('indexed_cookies', cache.uuid)
            indexed = p.execute()
            if all(indexed):
                continue
            try:
                ct = self.lookyloo.get_crawled_tree(cache.uuid)
            except NoValidHarFile:
                self.logger.warning(f'Broken pickle for {cache.uuid}')
                self.lookyloo.remove_pickle(cache.uuid)
                continue

            if not indexed[0]:
                self.logger.info(f'Indexing urls for {cache.uuid}')
                self.lookyloo.indexing.index_url_capture(ct)
            if not indexed[1]:
                self.logger.info(f'Indexing resources for {cache.uuid}')
                self.lookyloo.indexing.index_body_hashes_capture(ct)
            if not indexed[2]:
                self.logger.info(f'Indexing cookies for {cache.uuid}')
                self.lookyloo.indexing.index_cookies_capture(ct)
            # NOTE: categories aren't taken in account here, should be fixed(?)
            # see indexing.index_categories_capture(capture_uuid, categories)


def main():
    i = BackgroundIndexer()
    i.run(sleep_in_sec=60)


if __name__ == '__main__':
    main()