from collections import namedtuple
import os, os.path
import pkg_resources
+import random
import re
import shutil
import pokedex.db.tables as tables
from pokedex.roomaji import romanize
-__all__ = ['open_index', 'lookup']
+__all__ = ['open_index', 'lookup', 'random_lookup']
INTERMEDIATE_LOOKUP_RESULTS = 25
MAX_LOOKUP_RESULTS = 10
LookupResult = namedtuple('LookupResult',
['object', 'name', 'language', 'exact'])
+
+def _parse_table_name(name):
+ """Takes a singular table name, table name, or table object and returns the
+ table name.
+
+ Returns None for a bogus name.
+ """
+ if hasattr(name, '__tablename__'):
+ return getattr(name, '__tablename__')
+ elif name in indexed_tables:
+ return name
+ elif name + 's' in indexed_tables:
+ return name + 's'
+ else:
+ # Bogus. Be nice and return dummy
+ return None
+
+
def lookup(input, valid_types=[], session=None, indices=None, exact_only=False):
"""Attempts to find some sort of object, given a database session and name.
# provided
valid_types = prefixes
+ # Random lookup
+ if name == 'random':
+ return random_lookup(indices=(index, speller),
+ session=session,
+ valid_types=valid_types)
+
# Do different things depending what the query looks like
# Note: Term objects do an exact match, so we don't have to worry about a
# query parser tripping on weird characters in the input
### Filter by type of object
type_terms = []
for valid_type in valid_types:
- if hasattr(valid_type, '__tablename__'):
- table_name = getattr(valid_type, '__tablename__')
- elif valid_type in indexed_tables:
- table_name = valid_type
- elif valid_type + 's' in indexed_tables:
- table_name = valid_type + 's'
- else:
- # Bogus. Be nice and ignore it
- continue
-
+ table_name = _parse_table_name(valid_type)
type_terms.append(whoosh.query.Term(u'table', table_name))
if type_terms:
# give us some padding, and should avoid that problem. Not a big deal if
# we lose the 25th-most-likely match anyway.
return objects[:MAX_LOOKUP_RESULTS]
+
+
+def random_lookup(valid_types=[], session=None, indices=None):
+ """Takes similar arguments as `lookup()`, but returns a random lookup
+ result from one of the provided `valid_types`.
+ """
+
+ tables = []
+ for valid_type in valid_types:
+ table_name = _parse_table_name(valid_type)
+ if table_name:
+ tables.append(indexed_tables[table_name])
+
+ if not tables:
+ tables = indexed_tables.values()
+
+ # Rather than create an array of many hundred items and pick randomly from
+ # it, just pick a number up to the total number of potential items, then
+ # pick randomly from that, and partition the whole range into chunks
+ total = 0
+ partitions = []
+ for table in tables:
+ count = session.query(table).count()
+ total += count
+ partitions.append((table, count))
+
+ n = random.randint(1, total)
+ while n > partitions[0][1]:
+ n -= partitions[0][1]
+ partitions.pop(0)
+
+ return lookup(unicode(n), valid_types=[ partitions[0][0] ],
+ indices=indices, session=session)