Vendor discord.py (#2387)

Signed-off-by: Toby Harradine <tobyharradine@gmail.com>

discord/ext/commands/cooldowns.py

@@ -0,0 +1,148 @@
+# -*- coding: utf-8 -*-
+
+"""
+The MIT License (MIT)
+
+Copyright (c) 2015-2017 Rapptz
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+"""
+
+import enum
+import time
+
+__all__ = ["BucketType", "Cooldown", "CooldownMapping"]
+
+
+class BucketType(enum.Enum):
+    default = 0
+    user = 1
+    guild = 2
+    channel = 3
+    member = 4
+    category = 5
+
+
+class Cooldown:
+    __slots__ = ("rate", "per", "type", "_window", "_tokens", "_last")
+
+    def __init__(self, rate, per, type):
+        self.rate = int(rate)
+        self.per = float(per)
+        self.type = type
+        self._window = 0.0
+        self._tokens = self.rate
+        self._last = 0.0
+
+        if not isinstance(self.type, BucketType):
+            raise TypeError("Cooldown type must be a BucketType")
+
+    def get_tokens(self, current=None):
+        if not current:
+            current = time.time()
+
+        tokens = self._tokens
+
+        if current > self._window + self.per:
+            tokens = self.rate
+        return tokens
+
+    def update_rate_limit(self):
+        current = time.time()
+        self._last = current
+
+        self._tokens = self.get_tokens(current)
+
+        # first token used means that we start a new rate limit window
+        if self._tokens == self.rate:
+            self._window = current
+
+        # check if we are rate limited
+        if self._tokens == 0:
+            return self.per - (current - self._window)
+
+        # we're not so decrement our tokens
+        self._tokens -= 1
+
+        # see if we got rate limited due to this token change, and if
+        # so update the window to point to our current time frame
+        if self._tokens == 0:
+            self._window = current
+
+    def reset(self):
+        self._tokens = self.rate
+        self._last = 0.0
+
+    def copy(self):
+        return Cooldown(self.rate, self.per, self.type)
+
+    def __repr__(self):
+        return "<Cooldown rate: {0.rate} per: {0.per} window: {0._window} tokens: {0._tokens}>".format(
+            self
+        )
+
+
+class CooldownMapping:
+    def __init__(self, original):
+        self._cache = {}
+        self._cooldown = original
+
+    @property
+    def valid(self):
+        return self._cooldown is not None
+
+    @classmethod
+    def from_cooldown(cls, rate, per, type):
+        return cls(Cooldown(rate, per, type))
+
+    def _bucket_key(self, msg):
+        bucket_type = self._cooldown.type
+        if bucket_type is BucketType.user:
+            return msg.author.id
+        elif bucket_type is BucketType.guild:
+            return (msg.guild or msg.author).id
+        elif bucket_type is BucketType.channel:
+            return msg.channel.id
+        elif bucket_type is BucketType.member:
+            return ((msg.guild and msg.guild.id), msg.author.id)
+        elif bucket_type is BucketType.category:
+            return (msg.channel.category or msg.channel).id
+
+    def _verify_cache_integrity(self):
+        # we want to delete all cache objects that haven't been used
+        # in a cooldown window. e.g. if we have a  command that has a
+        # cooldown of 60s and it has not been used in 60s then that key should be deleted
+        current = time.time()
+        dead_keys = [k for k, v in self._cache.items() if current > v._last + v.per]
+        for k in dead_keys:
+            del self._cache[k]
+
+    def get_bucket(self, message):
+        if self._cooldown.type is BucketType.default:
+            return self._cooldown
+
+        self._verify_cache_integrity()
+        key = self._bucket_key(message)
+        if key not in self._cache:
+            bucket = self._cooldown.copy()
+            self._cache[key] = bucket
+        else:
+            bucket = self._cache[key]
+
+        return bucket