Add events on exits

evennia/contrib/events/commands.py

@@ -287,7 +287,7 @@ class CmdEvent(COMMAND_DEFAULT_CLASS):
 
         definition = types.get(event_name, (None, "Chain event"))
         description = definition[1]
-        self.msg(description)
+        self.msg(raw(description))
 
         # Open the editor
         event = self.handler.add_event(obj, event_name, "",
@@ -356,7 +356,7 @@ class CmdEvent(COMMAND_DEFAULT_CLASS):
         # Check the definition of the event
         definition = types.get(event_name, (None, "Chained event"))
         description = definition[1]
-        self.msg(description)
+        self.msg(raw(description))
 
         # Open the editor
         event = dict(event)

evennia/contrib/events/handler.py

@@ -60,6 +60,23 @@ class EventsHandler(object):
         """
         return self.all().get(event_name, [])
 
+    def get_variable(self, variable_name):
+        """
+        Return the variable value or None.
+
+        Args:
+            variable_name (str): the name of the variable.
+
+        Returns:
+            Either the variable's value or None.
+
+        """
+        handler = type(self).script
+        if handler:
+            return handler.get_variable(variable_name)
+
+        return None
+
     def add(self, event_name, code, author=None, valid=False, parameters=""):
         """
         Add a new event for this object.

evennia/contrib/events/scripts.py

@@ -132,6 +132,31 @@ class EventHandler(DefaultScript):
 
         return types
 
+    def get_variable(self, variable_name):
+        """
+        Return the variable defined in the locals.
+
+        This can be very useful to check the value of a variable that can be modified in an event, and whose value will be used in code.  This system allows additional customization.
+
+        Args:
+            variable_name (str): the name of the variable to return.
+
+        Returns:
+            The variable if found in the locals.
+            None if not found in the locals.
+
+        Note:
+            This will return the variable from the current locals.
+            Keep in mind that locals are shared between events.  As
+            every event is called one by one, this doesn't pose
+            additional problems if you get the variable right after
+            an event has been executed.  If, however, you differ,
+            there's no guarantee the variable will be here or will
+            mean the same thing.
+
+        """
+        return self.ndb.current_locals.get(variable_name)
+
     def add_event(self, obj, event_name, code, author=None, valid=False,
             parameters=""):
         """

evennia/contrib/events/typeclasses.py

@@ -9,6 +9,105 @@ from evennia.contrib.events.custom import (
         create_event_type, patch_hook, create_time_event)
 from evennia.contrib.events.handler import EventsHandler
 
+class PatchedCharacter:
+
+    """Patched typeclass for DefaultCharcter."""
+
+    @staticmethod
+    @patch_hook(DefaultCharacter, "announce_move_from")
+    def announce_move_from(character, destination, msg=None, hook=None):
+        """
+        Called if the move is to be announced. This is
+        called while we are still standing in the old
+        location.  Customizing the message through events is possible.
+
+        Args:
+            destination (Object): The place we are going to.
+            msg (optional): a custom message to replace the default one.
+
+        """
+        if not character.location:
+            return
+
+        if msg:
+            string = msg
+        else:
+            string = "{character} is leaving {origin}, heading for {destination}."
+
+        # Get the exit from location to destination
+        location = character.location
+        exits = [o for o in location.contents if o.location is location and o.destination is destination]
+        if exits:
+            exits[0].events.call("msg_leave", character, exits[0],
+                    location, destination, string)
+            string = exits[0].events.get_variable("message")
+
+        mapping = {
+                "character": character,
+                "exit": exits[0] if exits else "somewhere",
+                "origin": location or "nowhere",
+                "destination": destination or "nowhere",
+        }
+
+        # If there's no string, don't display anything
+        # It can happen if the "message" variable in events is set to None
+        if not string:
+            return
+
+        location.msg_contents(string, exclude=(character, ), mapping=mapping)
+
+    @staticmethod
+    @patch_hook(DefaultCharacter, "announce_move_to")
+    def announce_move_to(character, source_location, msg=None, hook=None):
+        """
+        Called after the move if the move was not quiet. At this point
+        we are standing in the new location.
+
+        Args:
+            source_location (Object): The place we came from
+            msg (str, optional): the default message to be displayed.
+
+        """
+
+        if not source_location and character.location.has_player:
+            # This was created from nowhere and added to a player's
+            # inventory; it's probably the result of a create command.
+            string = "You now have %s in your possession." % self.get_display_name(self.location)
+            character.location.msg(string)
+            return
+
+        if source_location:
+            if msg:
+                string = msg
+            else:
+                string = "{character} arrives to {destination} from {origin}."
+        else:
+            string = "{character} arrives to {destination}."
+
+        origin = source_location
+        destination = character.location
+        if origin:
+            exits = [o for o in destination.contents if o.location is destination and o.destination is origin]
+            if exits:
+                exits[0].events.call("msg_arrive", character, exits[0],
+                        origin, destination, string)
+            string = exits[0].events.get_variable("message")
+
+        mapping = {
+                "character": character,
+                "exit": exits[0] if exits else "somewhere",
+                "origin": origin or "nowhere",
+                "destination": destination or "nowhere",
+        }
+
+        # If there's no string, don't display anything
+        # It can happen if the "message" variable in events is set to None
+        if not string:
+            return
+
+        destination.msg_contents(string, exclude=(character, ), mapping=mapping)
+
+
 class PatchedObject(object):
     @lazy_property
     def events(self):
@@ -37,9 +136,8 @@ class PatchedExit(object):
 
         """
         is_character = inherits_from(traversing_object, DefaultCharacter)
-        script = ScriptDB.objects.get(db_key="event_handler")
         if is_character:
-            allow = script.call_event(exit, "can_traverse", traversing_object,
+            allow = exit.events.call("can_traverse", traversing_object,
                     exit, exit.location)
             if not allow:
                 return
@@ -48,7 +146,7 @@ class PatchedExit(object):
 
         # After traversing
         if is_character:
-            script.call_event(exit, "traverse", traversing_object,
+            exit.events.call("traverse", traversing_object,
                     exit, exit.location, exit.destination)
 
 
@@ -66,6 +164,51 @@ create_event_type(DefaultExit, "can_traverse", ["character", "exit", "room"],
         exit: the exit to be traversed.
         room: the room in which stands the character before moving.
 """)
+create_event_type(DefaultExit, "msg_arrive", ["character", "exit",
+        "origin", "destination", "message"], """
+    Customize the message when a character arrives through this exit.
+    This event is called when a character arrives through this exit.
+    To customize the message that will be sent to the room where the
+    character arrives, change the value of the variable "message"
+    to give it your custom message.  The character itself will not be
+    notified.  You can use mapping between braces, like this:
+        message = "{character} climbs out of a hole."
+    In your mapping, you can use {character} (the character who has
+    arrived), {exit} (the exit), {origin} (the room in which
+    the character was), and {destination} (the room in which the character
+    now is).  If you need to customize the message with other information,
+    you can also set "message" to None and send something else instead.
+
+    Variables you can use in this event:
+        character: the character who is arriving through this exit.
+        exit: the exit having been traversed.
+        origin: the past location of the character.
+        destination: the current location of the character.
+        message: the message to be displayed in the destination.
+""")
+create_event_type(DefaultExit, "msg_leave", ["character", "exit",
+        "origin", "destination", "message"], """
+    Customize the message when a character leaves through this exit.
+    This event is called when a character leaves through this exit.
+    To customize the message that will be sent to the room where the
+    character came from, change the value of the variable "message"
+    to give it your custom message.  The character itself will not be
+    notified.  You can use mapping between braces, like this:
+        message = "{character} falls into a hole!"
+    In your mapping, you can use {character} (the character who is
+    about to leave), {exit} (the exit), {origin} (the room in which
+    the character is), and {destination} (the room in which the character
+    is heading for).  If you need to customize the message with other
+    information, you can also set "message" to None and send something
+    else instead.
+
+    Variables you can use in this event:
+        character: the character who is leaving through this exit.
+        exit: the exit being traversed.
+        origin: the location of the character.
+        destination: the destination of the character.
+        message: the message to be displayed in the location.
+""")
 create_event_type(DefaultExit, "traverse", ["character", "exit",
         "origin", "destination"], """
     After the characer has traversed through this exit.
@@ -98,4 +241,4 @@ create_event_type(DefaultRoom, "time", ["room"], """
 
     Variables you can use in this event:
         room: the room connected to this event.
-""", create_time_event)
+    """, create_time_event)