1 files changed, 70 insertions, 0 deletions
diff --git a/src/events.py b/src/events.py
new file mode 100644
index 00000000..2363eca8
--- /dev/null
+++ b/src/events.py
@@ -0,0 +1,70 @@
+#
+# This file is part of Poezio.
+#
+# Poezio is free software: you can redistribute it and/or modify
+# it under the terms of the zlib license. See the COPYING file.
+
+"""
+Defines the EventHandler class
+"""
+
+import logging
+log = logging.getLogger(__name__)
+
+class EventHandler(object):
+    """
+    A class keeping a list of possible events that are triggered
+    by poezio. You (a plugin for example) can add an event handler
+    associated with an event name, and whenever that event is triggered,
+    the callback is called
+    """
+    def __init__(self):
+        self.events = {
+            # when you are highlighted in a muc tab
+            'highlight': [],
+            'muc_say': [],
+            'conversation_say': [],
+            'private_say': [],
+            }
+
+    def add_event_handler(self, name, callback, first=True, last=False, position=None):
+        """
+        Add a callback to a given event.
+        Note that if that event name doesn’t exist, it just returns False.
+        If it was successfully added, it returns True
+        """
+        if name not in self.events:
+            return False
+
+        if first:
+            self.events[name].insert(0, callback)
+        elif last:
+            self.events[name].append(callback)
+        elif position != None and isinstance(position, int):
+            self.events[name].insert(position, callback)
+        else:
+            self.events[name].insert(0, callback)
+
+        return True
+
+    def trigger(self, name, *args, **kwargs):
+        """
+        Call all the callbacks associated to the given event name
+        """
+        callbacks = self.events[name]
+        for callback in callbacks:
+            callback(*args, **kwargs)
+
+    def del_event_handler(self, name, callback):
+        """
+        Remove the callback from the list of callbacks of the given event
+        """
+        if not name:
+            for event in self.events:
+                while callback in self.events[event]:
+                    self.events[event].remove(callback)
+            return True
+        else:
+            if callback in self.events[name]:
+                self.events[name].remove(callback)
+