Track reopened supply chests and fix API snapshots

mosfet/protocol/managers.py

@@ -1,10 +1,11 @@
 import json
+import time
 from math import floor
 from munch import Munch
 
 from minecraft.networking.packets import clientbound, serverbound
 from minecraft.networking.modern import (
-    AddEntityPacket, BlockEntityDataPacket, ContainerOpenPacket,
+    AddEntityPacket, BlockEntityDataPacket, BlockEventPacket, ContainerOpenPacket,
     ContainerSetContentPacket, ContainerSetSlotPacket, SetEntityDataPacket,
     nbt_plain,
     PaletteSection,
@@ -355,6 +356,78 @@ class WorldState:
                     self.center, self.radius)
 
 
+class ChestOpenManager:
+    """Track chest viewer-count events and report openings by other players."""
+    OWN_OPEN_TIMEOUT = 3.0
+
+    def __init__(self, global_state):
+        self.g = global_state
+        self.g.chest_viewers = self.g.get('chest_viewers') or {}
+        self.g.chest_open_events = self.g.get('chest_open_events') or []
+        self.g.last_chest_opened_by_other = None
+        self.g.connection.register_packet_listener(
+            self.handle_block_event, BlockEventPacket)
+
+    def _block_name(self, packet):
+        registry = getattr(self.g.connection, 'registry_ids', {}).get(
+            'minecraft:block', {})
+        name = next((name for name, block_id in registry.items()
+                     if block_id == packet.block_id), None)
+        if name is not None:
+            return name.removeprefix('minecraft:')
+        location = packet.location
+        state_id = self.g.chunks.get_block_at(
+            location.x, location.y, location.z)
+        return blocks.BLOCKS.get(state_id)
+
+    def handle_block_event(self, packet):
+        block_name = self._block_name(packet)
+        if (block_name is None or block_name == 'ender_chest' or
+                not (block_name == 'chest' or block_name.endswith('_chest')) or
+                packet.action != 1):
+            return
+
+        location = packet.location
+        position = (location.x, location.y, location.z)
+        viewers = packet.parameter
+        previous_viewers = self.g.chest_viewers.get(position, 0)
+        if viewers:
+            self.g.chest_viewers[position] = viewers
+        else:
+            self.g.chest_viewers.pop(position, None)
+
+        pending = self.g.get('pending_chest_open')
+        pending_age = (time.monotonic() - pending.get('requested_at', 0)
+                       if pending is not None else None)
+        pending_is_fresh = (pending_age is not None and
+                            0 <= pending_age <= self.OWN_OPEN_TIMEOUT)
+        is_bot_opening = (
+            pending_is_fresh and
+            tuple(pending.get('position', ())) == position
+        )
+        if pending is not None and (is_bot_opening or not pending_is_fresh):
+            self.g.pending_chest_open = None
+
+        if (viewers <= previous_viewers or
+                (is_bot_opening and
+                 viewers <= max(1, previous_viewers))):
+            return
+
+        event = {
+            'position': position,
+            'block': block_name,
+            'viewers': viewers,
+            'previous_viewers': previous_viewers,
+            'timestamp': time.time(),
+        }
+        self.g.last_chest_opened_by_other = event
+        self.g.chest_open_events.append(event)
+        del self.g.chest_open_events[:-100]
+        print('[chest] another player opened {} at {} ({} viewer{})'.format(
+            block_name, position, viewers, '' if viewers == 1 else 's'),
+            flush=True)
+
+
 class EntityManager:
     def __init__(self, global_state):
         self.g = global_state