1use serde::{de::DeserializeOwned, Serialize};
2
3use crate::Envelope;
4
5#[derive(Debug, thiserror::Error)]
6pub enum CodecError {
7 #[error("postcard encode failed: {0}")]
8 PostcardEncode(postcard::Error),
9 #[error("postcard decode failed: {0}")]
10 PostcardDecode(postcard::Error),
11 #[error("bincode encode failed: {0}")]
12 BincodeEncode(bincode::Error),
13 #[error("bincode decode failed: {0}")]
14 BincodeDecode(bincode::Error),
15}
16
17pub trait Codec {
18 fn encode<T: Serialize>(&self, value: &T) -> Result<Vec<u8>, CodecError>;
19 fn decode<T: DeserializeOwned>(&self, bytes: &[u8]) -> Result<T, CodecError>;
20}
21
22#[derive(Debug, Clone, Copy, Default)]
24pub struct PostcardCodec;
25
26impl Codec for PostcardCodec {
27 fn encode<T: Serialize>(&self, value: &T) -> Result<Vec<u8>, CodecError> {
28 postcard::to_allocvec(value).map_err(CodecError::PostcardEncode)
29 }
30
31 fn decode<T: DeserializeOwned>(&self, bytes: &[u8]) -> Result<T, CodecError> {
32 postcard::from_bytes(bytes).map_err(CodecError::PostcardDecode)
33 }
34}
35
36#[derive(Debug, Clone, Copy, Default)]
38pub struct BincodeCodec;
39
40impl Codec for BincodeCodec {
41 fn encode<T: Serialize>(&self, value: &T) -> Result<Vec<u8>, CodecError> {
42 bincode::serialize(value).map_err(CodecError::BincodeEncode)
43 }
44
45 fn decode<T: DeserializeOwned>(&self, bytes: &[u8]) -> Result<T, CodecError> {
46 bincode::deserialize(bytes).map_err(CodecError::BincodeDecode)
47 }
48}
49
50pub fn encode_envelope<T: Serialize>(
51 codec: &impl Codec,
52 payload: T,
53) -> Result<Vec<u8>, CodecError> {
54 codec.encode(&Envelope::new(payload))
55}
56
57pub fn decode_envelope<T: DeserializeOwned>(
58 codec: &impl Codec,
59 bytes: &[u8],
60) -> Result<Envelope<T>, CodecError> {
61 codec.decode(bytes)
62}
63
64#[cfg(test)]
65mod tests {
66 use super::*;
67 use crate::types::{
68 BlueprintIngredientView, BlueprintView, EntityState, TickDelta, ToolRequirementView,
69 Transform, WorldClock, WorldCoord,
70 };
71
72 fn sample_tick_delta() -> TickDelta {
73 TickDelta {
74 tick: 42,
75 entities: (0..15)
76 .map(|i| EntityState {
77 id: i + 1,
78 label: String::new(),
79 transform: Transform {
80 position: WorldCoord::surface(i as f32, i as f32 * 0.5),
81 yaw: 1.25,
82 velocity: crate::types::Velocity2D { vx: 0.5, vy: -0.2 },
83 },
84 vitals: None,
85 attributes: None,
86 skills: None,
87 inside_building: None,
88 tile_id: None,
89 paperdoll_ref: None,
90 presentation_state: None,
91 sprite_mode: None,
92 progression_xp: None,
93 })
94 .collect(),
95 resource_nodes: Vec::new(),
96 buildings: Vec::new(),
97 doors: Vec::new(),
98 npcs: Vec::new(),
99 inventory: Vec::new(),
100 blueprints: Vec::new(),
101 world_clock: WorldClock::default(),
102 ground_drops: Vec::new(),
103 placed_containers: Vec::new(),
104 combat: None,
105 interior_map: None,
106 quest_log: vec![],
107 hired_workers: Vec::new(),
108 interactables: vec![],
109 ledger: None,
110 career: None,
111 combat_fx: Vec::new(),
112 }
113 }
114
115 #[test]
116 fn postcard_blueprint_snapshot_roundtrip() {
117 let codec = PostcardCodec;
118 let delta = TickDelta {
119 tick: 1,
120 entities: vec![],
121 resource_nodes: vec![],
122 buildings: vec![],
123 doors: vec![],
124 npcs: vec![],
125 inventory: vec![],
126 blueprints: vec![BlueprintView {
127 id: "oak_to_lumber".into(),
128 label: "Saw Planks".into(),
129 output: "lumber".into(),
130 output_qty: 1,
131 craft_ticks: 60,
132 station: Some("woodworking".into()),
133 category: Some("woodworking".into()),
134 required_tools: vec![ToolRequirementView {
135 item: "handsaw".into(),
136 consumed: false,
137 }],
138 skill: None,
139 failure_chance: 0.0,
140 worker_train_copper: 0,
141 inputs: vec![BlueprintIngredientView {
142 template_id: "oak_log".into(),
143 quantity: 2,
144 consumed: true,
145 }],
146 }],
147 world_clock: WorldClock::default(),
148 ground_drops: vec![],
149 placed_containers: vec![],
150 combat: None,
151 interior_map: None,
152 quest_log: vec![],
153 hired_workers: Vec::new(),
154 interactables: vec![],
155 ledger: None,
156 career: None,
157 combat_fx: Vec::new(),
158 };
159 let bytes = codec.encode(&Envelope::new(delta.clone())).unwrap();
160 let decoded: Envelope<TickDelta> = codec.decode(&bytes).unwrap();
161 assert_eq!(decoded.payload, delta);
162 }
163
164 #[test]
165 fn postcard_roundtrip_tick_delta() {
166 let codec = PostcardCodec;
167 let original = Envelope::new(sample_tick_delta());
168 let bytes = codec.encode(&original).expect("encode");
169 let decoded: Envelope<TickDelta> = codec.decode(&bytes).expect("decode");
170 assert_eq!(original, decoded);
171 }
172
173 #[test]
174 fn bincode_roundtrip_tick_delta() {
175 let codec = BincodeCodec;
176 let original = Envelope::new(sample_tick_delta());
177 let bytes = codec.encode(&original).expect("encode");
178 let decoded: Envelope<TickDelta> = codec.decode(&bytes).expect("decode");
179 assert_eq!(original, decoded);
180 }
181
182 #[test]
183 fn postcard_many_entities_vitals_none() {
184 let delta = TickDelta {
185 tick: 42,
186 entities: (0..15)
187 .map(|i| EntityState {
188 id: i + 1,
189 label: String::new(),
190 transform: Transform {
191 position: WorldCoord::surface(i as f32, i as f32 * 0.5),
192 yaw: 1.25,
193 velocity: crate::types::Velocity2D { vx: 0.5, vy: -0.2 },
194 },
195 vitals: None,
196 attributes: None,
197 skills: None,
198 inside_building: None,
199 tile_id: None,
200 paperdoll_ref: None,
201 presentation_state: None,
202 sprite_mode: None,
203 progression_xp: None,
204 })
205 .collect(),
206 resource_nodes: vec![],
207 buildings: vec![],
208 doors: vec![],
209 npcs: vec![],
210 inventory: vec![],
211 blueprints: vec![],
212 world_clock: WorldClock::default(),
213 ground_drops: vec![],
214 placed_containers: vec![],
215 combat: None,
216 interior_map: None,
217 quest_log: vec![],
218 hired_workers: Vec::new(),
219 interactables: vec![],
220 ledger: None,
221 career: None,
222 combat_fx: Vec::new(),
223 };
224 let codec = PostcardCodec;
225 let bytes = codec.encode(&Envelope::new(delta.clone())).unwrap();
226 let decoded: Envelope<TickDelta> = codec.decode(&bytes).unwrap();
227 assert_eq!(decoded.payload, delta);
228 }
229}