2014-08-12 00:15:41 +02:00
|
|
|
// Copyright (c) 2014 Couchbase, Inc.
|
|
|
|
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
|
|
|
|
// except in compliance with the License. You may obtain a copy of the License at
|
|
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
// Unless required by applicable law or agreed to in writing, software distributed under the
|
|
|
|
// License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
|
|
|
|
// either express or implied. See the License for the specific language governing permissions
|
|
|
|
// and limitations under the License.
|
2014-08-14 03:14:47 +02:00
|
|
|
package fa
|
2014-08-12 00:15:41 +02:00
|
|
|
|
|
|
|
import (
|
|
|
|
"bytes"
|
|
|
|
|
|
|
|
"github.com/couchbaselabs/bleve/analysis"
|
2014-08-14 03:14:47 +02:00
|
|
|
"github.com/couchbaselabs/bleve/registry"
|
2014-08-12 00:15:41 +02:00
|
|
|
)
|
|
|
|
|
2014-08-14 03:14:47 +02:00
|
|
|
const NormalizeName = "normalize_fa"
|
|
|
|
|
2014-08-12 00:15:41 +02:00
|
|
|
const (
|
|
|
|
YEH = '\u064A'
|
|
|
|
FARSI_YEH = '\u06CC'
|
|
|
|
YEH_BARREE = '\u06D2'
|
|
|
|
KEHEH = '\u06A9'
|
|
|
|
KAF = '\u0643'
|
|
|
|
HAMZA_ABOVE = '\u0654'
|
|
|
|
HEH_YEH = '\u06C0'
|
|
|
|
HEH_GOAL = '\u06C1'
|
|
|
|
HEH = '\u0647'
|
|
|
|
)
|
|
|
|
|
|
|
|
type PersianNormalizeFilter struct {
|
|
|
|
}
|
|
|
|
|
|
|
|
func NewPersianNormalizeFilter() *PersianNormalizeFilter {
|
|
|
|
return &PersianNormalizeFilter{}
|
|
|
|
}
|
|
|
|
|
|
|
|
func (s *PersianNormalizeFilter) Filter(input analysis.TokenStream) analysis.TokenStream {
|
|
|
|
rv := make(analysis.TokenStream, 0)
|
|
|
|
|
|
|
|
for _, token := range input {
|
|
|
|
term := normalize(token.Term)
|
|
|
|
token.Term = term
|
|
|
|
rv = append(rv, token)
|
|
|
|
}
|
|
|
|
|
|
|
|
return rv
|
|
|
|
}
|
|
|
|
|
|
|
|
func normalize(input []byte) []byte {
|
|
|
|
runes := bytes.Runes(input)
|
|
|
|
for i := 0; i < len(runes); i++ {
|
|
|
|
switch runes[i] {
|
|
|
|
case FARSI_YEH, YEH_BARREE:
|
|
|
|
runes[i] = YEH
|
|
|
|
case KEHEH:
|
|
|
|
runes[i] = KAF
|
|
|
|
case HEH_YEH, HEH_GOAL:
|
|
|
|
runes[i] = HEH
|
|
|
|
case HAMZA_ABOVE: // necessary for HEH + HAMZA
|
|
|
|
runes = analysis.DeleteRune(runes, i)
|
|
|
|
i--
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return analysis.BuildTermFromRunes(runes)
|
|
|
|
}
|
2014-08-14 03:14:47 +02:00
|
|
|
|
|
|
|
func NormalizerFilterConstructor(config map[string]interface{}, cache *registry.Cache) (analysis.TokenFilter, error) {
|
|
|
|
return NewPersianNormalizeFilter(), nil
|
|
|
|
}
|
|
|
|
|
|
|
|
func init() {
|
|
|
|
registry.RegisterTokenFilter(NormalizeName, NormalizerFilterConstructor)
|
|
|
|
}
|