world implementation part1

.gitignore

@@ -1,6 +1,5 @@
 */target
 /target
-/.tuffous/config_gui.json
 /.vscode
 /.idea
 /.VSCodeCounter

crates/core/block-entity/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "rimecraft-block-entity"
+version = "0.1.0"
+edition = "2021"
+authors = ["JieningYu <[email protected]>"]
+description = "Minecraft block entity primitives"
+repository = "https://github.com/rimecraft-rs/rimecraft/"
+license = "AGPL-3.0-or-later"
+categories = []
+
+[badges]
+maintenance = { status = "passively-maintained" }
+
+[dependencies]
+rimecraft-global-cx = { path = "../global-cx" }
+rimecraft-registry = { path = "../../util/registry" }
+rimecraft-block = { path = "../block" }
+rimecraft-voxel-math = { path = "../../util/voxel-math" }
+rimecraft-downcast = { path = "../../util/downcast" }
+ahash = "0.8"
+serde = "1.0"
+erased-serde = "0.4"
+rimecraft-serde-update = { path = "../../util/serde-update", features = ["erased"] }
+
+[features]
+
+[lints]
+workspace = true

crates/core/block-entity/src/deser_nbt.rs

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+//! Helper module for deserializing NBT data into block entities.
+
+use std::{fmt::Debug, hash::Hash, marker::PhantomData};
+
+use rimecraft_block::{BlockState, ProvideBlockStateExtTy};
+use rimecraft_global_cx::ProvideNbtTy;
+use rimecraft_registry::ProvideRegistry;
+use rimecraft_voxel_math::BlockPos;
+use serde::{de::DeserializeSeed, Deserialize, Deserializer};
+
+use crate::{BlockEntity, ProvideBlockEntity, RawBlockEntityTypeDyn};
+
+/// The dummy value for block entity types.
+pub const DUMMY: &str = "DUMMY";
+
+/// A [`DeserializeSeed`] for [`BlockEntity`].
+///
+/// This deserializes the id of the block entity type and its data.
+pub struct CreateFromNbt<'w, Cx>
+where
+    Cx: ProvideBlockStateExtTy,
+{
+    /// The position of the block entity.
+    pub pos: BlockPos,
+    /// The state of the [`Block`] the block entity belongs to.
+    pub state: BlockState<'w, Cx>,
+
+    /// Whether to respect the [`DUMMY`] value.
+    pub respect_dummy: bool,
+}
+
+impl<Cx> Debug for CreateFromNbt<'_, Cx>
+where
+    Cx: ProvideBlockStateExtTy + Debug,
+    Cx::BlockStateExt: Debug,
+    Cx::Id: Debug,
+{
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("CreateFromNbt")
+            .field("pos", &self.pos)
+            .field("state", &self.state)
+            .finish()
+    }
+}
+
+impl<'w, 'de, Cx> DeserializeSeed<'de> for CreateFromNbt<'w, Cx>
+where
+    Cx: ProvideBlockStateExtTy
+        + ProvideRegistry<'w, Cx::Id, RawBlockEntityTypeDyn<'w, Cx>>
+        + ProvideNbtTy,
+    Cx::Id: Deserialize<'de> + Hash + Eq,
+    Cx::BlockStateExt: ProvideBlockEntity<'w, Cx>,
+{
+    type Value = Option<Box<BlockEntity<'w, Cx>>>;
+
+    fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        struct Visitor<'w, Cx>(CreateFromNbt<'w, Cx>)
+        where
+            Cx: ProvideBlockStateExtTy;
+
+        impl<'de, 'w, Cx> serde::de::Visitor<'de> for Visitor<'w, Cx>
+        where
+            Cx: ProvideBlockStateExtTy
+                + ProvideRegistry<'w, Cx::Id, RawBlockEntityTypeDyn<'w, Cx>>
+                + ProvideNbtTy,
+            Cx::Id: Deserialize<'de> + Hash + Eq,
+            Cx::BlockStateExt: ProvideBlockEntity<'w, Cx>,
+        {
+            type Value = Option<Box<BlockEntity<'w, Cx>>>;
+
+            fn expecting(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                formatter.write_str("a block entity")
+            }
+
+            fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
+            where
+                A: serde::de::MapAccess<'de>,
+            {
+                use serde::__private::de::Content;
+
+                let mut id: Option<Cx::Id> = None;
+                let mut is_dummy = false;
+                let mut collect: Vec<Option<(Content<'de>, Content<'de>)>> =
+                    Vec::with_capacity(map.size_hint().map_or(0, |i| i - 1));
+
+                enum Field<'de> {
+                    Id,
+                    Other(Content<'de>),
+                }
+
+                impl<'de> Deserialize<'de> for Field<'de> {
+                    fn deserialize<D>(deserializer: D) -> Result<Field<'de>, D::Error>
+                    where
+                        D: Deserializer<'de>,
+                    {
+                        struct FieldVisitor;
+
+                        impl<'de> serde::de::Visitor<'de> for FieldVisitor {
+                            type Value = Field<'de>;
+
+                            fn expecting(
+                                &self,
+                                formatter: &mut std::fmt::Formatter<'_>,
+                            ) -> std::fmt::Result {
+                                formatter.write_str("a field")
+                            }
+
+                            fn visit_str<E>(self, v: &str) -> Result<Field<'de>, E>
+                            where
+                                E: serde::de::Error,
+                            {
+                                match v {
+                                    "id" => Ok(Field::Id),
+                                    _ => Ok(Field::Other(Content::String(v.into()))),
+                                }
+                            }
+                        }
+
+                        deserializer.deserialize_identifier(FieldVisitor)
+                    }
+                }
+
+                #[derive(Deserialize)]
+                #[serde(untagged)]
+                enum MaybeDummy<T> {
+                    Dummy(Dummy),
+                    Value(T),
+                }
+
+                pub struct Dummy;
+
+                impl<'de> Deserialize<'de> for Dummy {
+                    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+                    where
+                        D: Deserializer<'de>,
+                    {
+                        struct DummyVisitor;
+
+                        impl serde::de::Visitor<'_> for DummyVisitor {
+                            type Value = Dummy;
+
+                            fn expecting(
+                                &self,
+                                f: &mut std::fmt::Formatter<'_>,
+                            ) -> std::fmt::Result {
+                                write!(f, "a '{}' value", DUMMY)
+                            }
+
+                            #[inline]
+                            fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+                            where
+                                E: serde::de::Error,
+                            {
+                                if v == DUMMY {
+                                    Ok(Dummy)
+                                } else {
+                                    Err(serde::de::Error::custom("expected 'DUMMY'"))
+                                }
+                            }
+                        }
+
+                        deserializer.deserialize_str(DummyVisitor)
+                    }
+                }
+
+                while let Some(key) = map.next_key()? {
+                    match key {
+                        Field::Id => {
+                            if id.is_some() {
+                                return Err(serde::de::Error::duplicate_field("id"));
+                            }
+
+                            if self.0.respect_dummy {
+                                let dummy: MaybeDummy<Cx::Id> = map.next_value()?;
+                                match dummy {
+                                    MaybeDummy::Dummy(Dummy) => {
+                                        is_dummy = true;
+                                    }
+                                    MaybeDummy::Value(i) => {
+                                        id = Some(i);
+                                    }
+                                }
+                            } else {
+                                id = Some(map.next_value()?);
+                            }
+                        }
+                        Field::Other(content) => {
+                            collect.push(Some((content, map.next_value()?)));
+                        }
+                    }
+                }
+
+                if is_dummy {
+                    let state = self.0.state.state;
+                    let res = if let Some(constructor) =
+                        ProvideBlockEntity::block_entity_constructor(state.data())
+                    {
+                        Ok(Some(constructor(self.0.pos)))
+                    } else {
+                        Ok(None)
+                    };
+                    res
+                } else {
+                    let id = id.ok_or_else(|| serde::de::Error::missing_field("id"))?;
+                    let registry: &rimecraft_registry::Registry<_, RawBlockEntityTypeDyn<'w, Cx>> =
+                        Cx::registry();
+                    let ty = registry.get(&id).ok_or_else(|| {
+                        serde::de::Error::custom(format!("unknown block entity type: {}", id))
+                    })?;
+
+                    let mut be = ty.instantiate(self.0.pos, self.0.state);
+                    // Update the block entity data.
+                    if let Some(be) = &mut be {
+                        rimecraft_serde_update::Update::update(
+                            &mut be.data,
+                            serde::__private::de::FlatMapDeserializer(&mut collect, PhantomData),
+                        )?;
+                    }
+                    Ok(be)
+                }
+            }
+        }
+
+        deserializer.deserialize_map(Visitor(self))
+    }
+}