Refactored _get_suggestions following Mark's suggestions about inefficiency.

- Matching scores will be calculated once now and stored in the dict `scores`.
- Allow `_get_suggestions()` to go through a list of score threshold and return the first list of matching tags that's not empty and above the threshold. This avoid calling the function multiple time like before ( `self._get_suggestions(tag_name, 100) or self._get_suggestions(tag_name, 80)` for example, is calling this function twice, and is inefficient )
- Deleted commented line.
- Added `typing` module for more typehints.

1 files changed, 24 insertions, 12 deletions

diff --git a/bot/cogs/tags.py b/bot/cogs/tags.py
index 9e06b702c..8d3586b19 100644
--- a/bot/cogs/tags.py
+++ b/bot/cogs/tags.py
@@ -1,5 +1,6 @@
 import logging
 import time
+from typing import Dict, List, Optional
 
 from discord import Colour, Embed
 from discord.ext.commands import Cog, Context, group
@@ -39,9 +40,9 @@ class Tags(Cog):
             self._last_fetch = time_now
 
     @staticmethod
-    def _fuzzy_search(search: str, target: str) -> bool:
-        found = 0
-        index = 0
+    def _fuzzy_search(search: str, target: str) -> int:
+        """A simple scoring algorithm based on how many letters are found / total, with order in mind."""
+        found, index = 0, 0
         _search = search.lower().replace(' ', '')
         _target = target.lower().replace(' ', '')
         for letter in _search:
@@ -51,19 +52,32 @@ class Tags(Cog):
             found += index > 0
         return found / len(_search) * 100
 
-    def _get_suggestions(self, tag_name: str, score: int) -> list:
-        return sorted(
-            (tag for tag in self._cache.values() if Tags._fuzzy_search(tag_name, tag['title']) >= score),
-            key=lambda tag: Tags._fuzzy_search(tag_name, tag['title']),
-            reverse=True
-        )
+    def _get_suggestions(self, tag_name: str, thresholds: Optional[List[int]] = None) -> List[str]:
+        """Return a list of suggested tags."""
+        scores: Dict[str, int] = {
+            tag_title: Tags._fuzzy_search(tag_name, tag['title'])
+            for tag_title, tag in self._cache.items()
+        }
+
+        thresholds = thresholds or [100, 80]
+
+        for threshold in thresholds:
+            suggestions = [
+                self._cache[tag_title]
+                for tag_title, matching_score in scores.items()
+                if matching_score >= threshold
+            ]
+            if suggestions:
+                return suggestions
+
+        return []
 
     async def _get_tag(self, tag_name: str) -> list:
         """Get a specific tag."""
         await self._get_tags()
         found = [self._cache.get(tag_name.lower(), None)]
         if not found[0]:
-            return self._get_suggestions(tag_name, 100) or self._get_suggestions(tag_name, 80)
+            return self._get_suggestions(tag_name, thresholds=[100, 80])
         return found
 
     @group(name='tags', aliases=('tag', 't'), invoke_without_command=True)
@@ -102,7 +116,6 @@ class Tags(Cog):
         await self._get_tags()
 
         if tag_name is not None:
-            # tag = await self.bot.api_client.get(f'bot/tags/{tag_name}')
             founds = await self._get_tag(tag_name)
 
             if len(founds) == 1:
@@ -120,7 +133,6 @@ class Tags(Cog):
                 ))
 
         else:
-            # tags = await self.bot.api_client.get('bot/tags')
             tags = self._cache.values()
             if not tags:
                 await ctx.send(embed=Embed(