From d5ae272adfb6e2ac41efceb8a7794a90d2483f35 Mon Sep 17 00:00:00 2001
From: Likith B <likith.b@couchbase.com>
Date: Fri, 9 Aug 2024 11:50:52 +0530
Subject: [PATCH] MB-61640: Fuzzy Dynamic Scoring

 - Allow edit distances for terms to be read
---
 automaton.go    | 5 +++++
 fst_iterator.go | 6 ++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/automaton.go b/automaton.go
index 70398f2..4014797 100644
--- a/automaton.go
+++ b/automaton.go
@@ -83,3 +83,8 @@ func (m *AlwaysMatch) Accept(int, byte) int {
 
 // creating an alwaysMatchAutomaton to avoid unnecessary repeated allocations.
 var alwaysMatchAutomaton = &AlwaysMatch{}
+
+type FuzzyAutomaton interface {
+	Automaton
+	EditDistance(int) uint8
+}
diff --git a/fst_iterator.go b/fst_iterator.go
index 1fc2b99..948d1e6 100644
--- a/fst_iterator.go
+++ b/fst_iterator.go
@@ -16,8 +16,6 @@ package vellum
 
 import (
 	"bytes"
-
-	"github.com/blevesearch/vellum/levenshtein"
 )
 
 // Iterator represents a means of visiting key/value pairs in order.
@@ -219,8 +217,8 @@ OUTER:
 
 			cmp := bytes.Compare(i.keysStack, i.nextStart)
 			if cmp > 0 {
-				if dfa, ok := i.aut.(*levenshtein.DFA); ok {
-					i.keysDistance = dfa.EditDistance(autCurr)
+				if fa, ok := i.aut.(FuzzyAutomaton); ok {
+					i.keysDistance = fa.EditDistance(autCurr)
 				}
 				// in final state greater than start key
 				return nil