// Copyright 2024 drey7925
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// SPDX-License-Identifier: Apache-2.0

syntax = "proto3";

package perovskite.protocol.entities;

import "coordinates.proto";
import "render.proto";

message EntityMove {
  // The starting position for the movement
  perovskite.protocol.coordinates.Vec3D start_position = 1;
  // The initial velocity of the movement
  perovskite.protocol.coordinates.Vec3F velocity = 2;
  // The acceleration of the movement
  perovskite.protocol.coordinates.Vec3F acceleration = 3;
  reserved 4;
  // The face direction (about the vertical Y axis) in radians. 0 means facing +z
  float face_direction = 5;
  // The pitch up/down in radians. Positive means pitch up
  float pitch = 9;
  // The sequence number of the move.
  uint64 sequence = 6;
  // The total time scheduled for the movement, nanosecond ticks
  uint64 time_ticks = 7;
  // The tick on which the move is scheduled to start
  // This is synchronized with the timebase used for ticks in every stream message
  uint64 start_tick = 8;
}

message EntityUpdate {
  // The unique ID of the entity.
  uint64 id = 1;
  // The moves that are queued for this move, and have not yet been delivered to
  // this client
  repeated EntityMove planned_move = 2;
  reserved 3, 4;

  // If true, the entity should stop being displayed. If so, ignore all other
  // fields
  bool remove = 5;

  // todo later - appearance, including the ability to change the appearance on
  // demand
  // The entity's class, controlling its appearance
  uint32 entity_class = 6;
  // Entities trailing behind this entity. Note that these have less functionality;
  // they essentially just follow behind it, while the location of the primary entity
  // is used for things like collision detection, proximity queries, etc. The exact
  // set of limitations is still TBD
  repeated TrailingEntity trailing_entity = 7;
}

// Secondary entities that trail behind the main entity at fixed distance, e.g.
// ducklings following a duck, or minecarts coupled into a train.
message TrailingEntity {
  uint32 class = 1;
  float distance = 2;
}

message EntityTypeAssignment {
  string short_name = 1;
  uint32 entity_class = 2;
}

message ServerEntityTypeAssignments {
  repeated EntityTypeAssignment entity_type = 1;
}

message EntityDef {
  string short_name = 1;
  uint32 entity_class = 2;
  EntityAppearance appearance = 3;
}

message EntityAppearance {
  // The mesh to use for the entity. At least one must be specified.
  repeated perovskite.protocol.render.CustomMesh custom_mesh = 1;
  // The offset to move the player position when attached to this entity.
  perovskite.protocol.coordinates.Vec3D attachment_offset = 2;
  // If true, the attachment offset is given in model space and will be transformed
  // subject to the angle of the entity. If false, the attachment offset is given
  // in world space and undergoes no transformation
  bool attachment_offset_in_model_space = 3;
}