From d491a46a215c8515547c9fdd28c2ad2ad50b0b69 Mon Sep 17 00:00:00 2001
From: 18alantom <2.alan.tom@gmail.com>
Date: Fri, 26 Nov 2021 12:51:47 +0530
Subject: [PATCH] fix: autocomplete behaviour, use fuzzy matching

---
 src/components/Controls/AutoComplete.vue | 18 +++++----
 src/components/Dropdown.vue              | 48 ++++++++++++++++--------
 src/utils.js                             | 30 +++++++++++++++
 3 files changed, 73 insertions(+), 23 deletions(-)

diff --git a/src/components/Controls/AutoComplete.vue b/src/components/Controls/AutoComplete.vue
index a5aba264..f7926223 100644
--- a/src/components/Controls/AutoComplete.vue
+++ b/src/components/Controls/AutoComplete.vue
@@ -34,6 +34,7 @@
 <script>
 import Base from './Base';
 import Dropdown from '@/components/Dropdown';
+import { fuzzyMatch } from '@/utils';
 
 export default {
   name: 'AutoComplete',
@@ -97,13 +98,11 @@ export default {
         return items;
       }
 
-      return items.filter((d) => {
-        let key = keyword.toLowerCase();
-        return (
-          d.label.toLowerCase().includes(key) ||
-          d.value.toLowerCase().includes(key)
-        );
-      });
+      return items
+        .map((item) => ({ ...fuzzyMatch(keyword, item.value), item }))
+        .filter(({ isMatch }) => isMatch)
+        .sort((a, b) => a.distance - b.distance)
+        .map(({ item }) => item);
     },
     setSuggestion(suggestion) {
       this.linkValue = suggestion.value;
@@ -121,7 +120,10 @@ export default {
         this.triggerChange('');
       }
 
-      if (value && !this.suggestions.includes(value)) {
+      if (
+        value &&
+        !this.suggestions.map(({ value }) => value).includes(value)
+      ) {
         const suggestion = await this.getSuggestions(value);
 
         if (suggestion.length < 2) {
diff --git a/src/components/Dropdown.vue b/src/components/Dropdown.vue
index 13817a75..89186cfb 100644
--- a/src/components/Dropdown.vue
+++ b/src/components/Dropdown.vue
@@ -25,17 +25,35 @@
           <div v-for="d in dropdownItems" :key="d.label">
             <div
               v-if="d.isGroup"
-              class="px-2 pt-3 pb-1 text-xs uppercase text-gray-700 font-semibold tracking-wider"
+              class="
+                px-2
+                pt-3
+                pb-1
+                text-xs
+                uppercase
+                text-gray-700
+                font-semibold
+                tracking-wider
+              "
             >
               {{ d.label }}
             </div>
             <a
               v-else
               ref="items"
-              class="block p-2 rounded-md mt-1 first:mt-0 cursor-pointer truncate"
+              class="
+                block
+                p-2
+                rounded-md
+                mt-1
+                first:mt-0
+                cursor-pointer
+                truncate
+              "
               :class="d.index === highlightedIndex ? 'bg-gray-100' : ''"
               @mouseenter="highlightedIndex = d.index"
               @mouseleave="highlightedIndex = -1"
+              @mousedown.prevent
               @click="selectItem(d)"
             >
               <component :is="d.component" v-if="d.component" />
@@ -57,28 +75,28 @@ export default {
   props: {
     items: {
       type: Array,
-      default: () => []
+      default: () => [],
     },
     groups: {
       type: Array,
-      default: null
+      default: null,
     },
     right: {
       type: Boolean,
-      default: false
+      default: false,
     },
     isLoading: {
       type: Boolean,
-      default: false
-    }
+      default: false,
+    },
   },
   components: {
-    Popover
+    Popover,
   },
   data() {
     return {
       isShown: false,
-      highlightedIndex: -1
+      highlightedIndex: -1,
     };
   },
   computed: {
@@ -88,7 +106,7 @@ export default {
       }
       let groupNames = uniq(
         this.items
-          .map(d => d.group)
+          .map((d) => d.group)
           .filter(Boolean)
           .sort()
       );
@@ -111,7 +129,7 @@ export default {
         let i = 0;
         for (let group of this.sortedGroups) {
           let groupItems = itemsByGroup[group];
-          groupItems = groupItems.map(d => {
+          groupItems = groupItems.map((d) => {
             d.index = i;
             i++;
             return d;
@@ -119,7 +137,7 @@ export default {
           items = items.concat(
             {
               label: group,
-              isGroup: true
+              isGroup: true,
             },
             groupItems
           );
@@ -132,7 +150,7 @@ export default {
         d.index = i;
         return d;
       });
-    }
+    },
   },
   methods: {
     selectItem(d) {
@@ -181,7 +199,7 @@ export default {
       let highlightedElement = this.$refs.items[this.highlightedIndex];
       highlightedElement &&
         highlightedElement.scrollIntoView({ block: 'nearest' });
-    }
-  }
+    },
+  },
 };
 </script>
diff --git a/src/utils.js b/src/utils.js
index 01fbcf11..7cde188d 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -351,3 +351,33 @@ export function purgeCache(purgeAll = false) {
       delete frappe[d];
     });
 }
+
+export function fuzzyMatch(keyword, candidate) {
+  const keywordLetters = [...keyword];
+  const candidateLetters = [...candidate];
+
+  let keywordLetter = keywordLetters.shift();
+  let candidateLetter = candidateLetters.shift();
+
+  let isMatch = true;
+  let distance = 0;
+
+  while (keywordLetter && candidateLetter) {
+    if (keywordLetter.toLowerCase() === candidateLetter.toLowerCase()) {
+      keywordLetter = keywordLetters.shift();
+    } else {
+      distance += 1;
+    }
+
+    candidateLetter = candidateLetters.shift();
+  }
+
+  if (keywordLetter !== undefined) {
+    distance = -1;
+    isMatch = false;
+  } else {
+    distance += candidateLetters.length;
+  }
+
+  return { isMatch, distance };
+}