Add World::find_block (#80)

* start adding World::find_block

* keep working on find_block

* BlockStates

* fix sorting

* update examples that use find_one_block

* azalea_block::properties

* fix tests

* add a gotoblock command to testbot

18 files changed, 619 insertions, 156 deletions

diff --git a/azalea-block/README.md b/azalea-block/README.md
index e4b6357b..9be4c79b 100755
--- a/azalea-block/README.md
+++ b/azalea-block/README.md
@@ -8,11 +8,11 @@ There's three block types, used for different things. You can (mostly) convert b
 
 ```
 # use azalea_block::BlockState;
-let block_state: BlockState = azalea_block::CobblestoneWallBlock {
-    east: azalea_block::EastWall::Low,
-    north: azalea_block::NorthWall::Low,
-    south: azalea_block::SouthWall::Low,
-    west: azalea_block::WestWall::Low,
+let block_state: BlockState = azalea_block::blocks::CobblestoneWall {
+    east: azalea_block::properties::EastWall::Low,
+    north: azalea_block::properties::NorthWall::Low,
+    south: azalea_block::properties::SouthWall::Low,
+    west: azalea_block::properties::WestWall::Low,
     up: false,
     waterlogged: false,
 }
@@ -36,7 +36,7 @@ let block = Box::<dyn Block>::from(block_state);
 ```
 # use azalea_block::{Block, BlockState};
 # let block_state: BlockState = azalea_registry::Block::Jukebox.into();
-if let Some(jukebox) = Box::<dyn Block>::from(block_state).downcast_ref::<azalea_block::JukeboxBlock>() {
+if let Some(jukebox) = Box::<dyn Block>::from(block_state).downcast_ref::<azalea_block::blocks::Jukebox>() {
     // ...
 }
 ```
diff --git a/azalea-block/azalea-block-macros/src/lib.rs b/azalea-block/azalea-block-macros/src/lib.rs
index b69ebd06..a8739e7c 100755
--- a/azalea-block/azalea-block-macros/src/lib.rs
+++ b/azalea-block/azalea-block-macros/src/lib.rs
@@ -38,7 +38,7 @@ struct PropertyDefinitions {
     properties: Vec<PropertyDefinition>,
 }
 
-/// `snowy: false` or `axis: Axis::Y`
+/// `snowy: false` or `axis: properties::Axis::Y`
 #[derive(Debug)]
 struct PropertyWithNameAndDefault {
     name: Ident,
@@ -59,7 +59,7 @@ struct BlockDefinition {
 }
 impl Parse for PropertyWithNameAndDefault {
     fn parse(input: ParseStream) -> Result<Self> {
-        // `snowy: false` or `axis: Axis::Y`
+        // `snowy: false` or `axis: properties::Axis::Y`
         let property_name = input.parse()?;
         input.parse::<Token![:]>()?;
 
@@ -74,7 +74,7 @@ impl Parse for PropertyWithNameAndDefault {
             is_enum = true;
             property_type = first_ident;
             let variant = input.parse::<Ident>()?;
-            property_default.extend(quote! { ::#variant });
+            property_default = quote! { properties::#property_default::#variant };
         } else if first_ident_string == "true" || first_ident_string == "false" {
             property_type = Ident::new("bool", first_ident.span());
         } else {
@@ -310,6 +310,7 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
     let mut from_state_to_block_match = quote! {};
     let mut from_registry_block_to_block_match = quote! {};
     let mut from_registry_block_to_blockstate_match = quote! {};
+    let mut from_registry_block_to_blockstates_match = quote! {};
 
     for block in &input.block_definitions.blocks {
         let block_property_names = &block
@@ -386,13 +387,16 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
         for PropertyWithNameAndDefault {
             property_type: struct_name,
             name,
+            is_enum,
             ..
         } in &properties_with_name
         {
             // let property_name_snake =
             //     Ident::new(&property.to_string(), proc_macro2::Span::call_site());
-            block_struct_fields.extend(quote! {
-                pub #name: #struct_name,
+            block_struct_fields.extend(if *is_enum {
+                quote! { pub #name: properties::#struct_name, }
+            } else {
+                quote! { pub #name: #struct_name, }
             });
         }
 
@@ -400,10 +404,7 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
             &to_pascal_case(&block.name.to_string()),
             proc_macro2::Span::call_site(),
         );
-        let block_struct_name = Ident::new(
-            &format!("{block_name_pascal_case}Block"),
-            proc_macro2::Span::call_site(),
-        );
+        let block_struct_name = Ident::new(&block_name_pascal_case.to_string(), proc_macro2::Span::call_site());
 
         let mut from_block_to_state_match_inner = quote! {};
 
@@ -445,7 +446,7 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
                 }
 
                 let property_type = if property.is_enum {
-                    quote! {#property_struct_name_ident::#variant}
+                    quote! {properties::#property_struct_name_ident::#variant}
                 } else {
                     quote! {#variant}
                 };
@@ -476,9 +477,9 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
         // 7035..=7058 => {
         //     let b = b - 7035;
         //     &AcaciaButtonBlock {
-        //         powered: Powered::from((b / 1) % 2),
-        //         facing: Facing::from((b / 2) % 4),
-        //         face: Face::from((b / 8) % 3),
+        //         powered: properties::Powered::from((b / 1) % 2),
+        //         facing: properties::Facing::from((b / 2) % 4),
+        //         face: properties::Face::from((b / 8) % 3),
         //     }
         // }
         let mut from_state_to_block_inner = quote! {};
@@ -498,7 +499,7 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
                     // this is not a mistake, it starts with true for some reason
                     quote! {(b / #division) % #property_variants_count == 0}
                 } else {
-                    quote! {#property_struct_name_ident::from((b / #division) % #property_variants_count)}
+                    quote! {properties::#property_struct_name_ident::from((b / #division) % #property_variants_count)}
                 }
             };
             from_state_to_block_inner.extend(quote! {
@@ -523,6 +524,9 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
         from_registry_block_to_blockstate_match.extend(quote! {
             azalea_registry::Block::#block_name_pascal_case => BlockState { id: #default_state_id },
         });
+        from_registry_block_to_blockstates_match.extend(quote! {
+            azalea_registry::Block::#block_name_pascal_case => BlockStates::from(#first_state_id..=#last_state_id),
+        });
 
         let mut block_default_fields = quote! {};
         for PropertyWithNameAndDefault {
@@ -560,14 +564,14 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
                 fn id(&self) -> &'static str {
                     #block_id
                 }
-                fn as_blockstate(&self) -> BlockState {
+                fn as_block_state(&self) -> BlockState {
                     #from_block_to_state_match
                 }
             }
 
             impl From<#block_struct_name> for BlockState {
                 fn from(b: #block_struct_name) -> Self {
-                    b.as_blockstate()
+                    b.as_block_state()
                 }
             }
 
@@ -585,21 +589,7 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
 
     let last_state_id = state_id - 1;
     let mut generated = quote! {
-        #property_enums
-
-        /// A representation of a state a block can be in. (for example, a stone
-        /// block only has one state but each possible stair rotation is a
-        /// different state).
-        #[derive(Copy, Clone, PartialEq, Eq, Default)]
-        pub struct BlockState {
-            /// The protocol ID for the block state. IDs may change every
-            /// version, so you shouldn't hard-code them or store them in databases.
-            pub id: u32
-        }
-
         impl BlockState {
-            pub const AIR: BlockState = BlockState { id: 0 };
-
             /// Returns the highest possible state ID.
             #[inline]
             pub fn max_state() -> u32 {
@@ -607,38 +597,50 @@ pub fn make_block_states(input: TokenStream) -> TokenStream {
             }
         }
 
-        impl std::fmt::Debug for BlockState {
-            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-                write!(f, "BlockState(id: {}, {:?})", self.id, Box::<dyn Block>::from(*self))
-            }
+        pub mod properties {
+            use super::*;
+
+            #property_enums
         }
     };
 
     generated.extend(quote! {
-        #block_structs
-
-        impl From<BlockState> for Box<dyn Block> {
-            fn from(block_state: BlockState) -> Self {
-                let b = block_state.id;
-                match b {
-                    #from_state_to_block_match
-                    _ => panic!("Invalid block state: {}", b),
+        pub mod blocks {
+            use super::*;
+
+            #block_structs
+
+            impl From<BlockState> for Box<dyn Block> {
+                fn from(block_state: BlockState) -> Self {
+                    let b = block_state.id;
+                    match b {
+                        #from_state_to_block_match
+                        _ => panic!("Invalid block state: {}", b),
+                    }
                 }
             }
-        }
-        impl From<azalea_registry::Block> for Box<dyn Block> {
-            fn from(block: azalea_registry::Block) -> Self {
-                match block {
-                    #from_registry_block_to_block_match
-                    _ => unreachable!("There should always be a block struct for every azalea_registry::Block variant")
+            impl From<azalea_registry::Block> for Box<dyn Block> {
+                fn from(block: azalea_registry::Block) -> Self {
+                    match block {
+                        #from_registry_block_to_block_match
+                        _ => unreachable!("There should always be a block struct for every azalea_registry::Block variant")
+                    }
                 }
             }
-        }
-        impl From<azalea_registry::Block> for BlockState {
-            fn from(block: azalea_registry::Block) -> Self {
-                match block {
-                    #from_registry_block_to_blockstate_match
-                    _ => unreachable!("There should always be a block state for every azalea_registry::Block variant")
+            impl From<azalea_registry::Block> for BlockState {
+                fn from(block: azalea_registry::Block) -> Self {
+                    match block {
+                        #from_registry_block_to_blockstate_match
+                        _ => unreachable!("There should always be a block state for every azalea_registry::Block variant")
+                    }
+                }
+            }
+            impl From<azalea_registry::Block> for BlockStates {
+                fn from(block: azalea_registry::Block) -> Self {
+                    match block {
+                        #from_registry_block_to_blockstates_match
+                        _ => unreachable!("There should always be a block state for every azalea_registry::Block variant")
+                    }
                 }
             }
         }
diff --git a/azalea-block/src/blocks.rs b/azalea-block/src/generated.rs
index e6923d59..afe6dfda 100755
--- a/azalea-block/src/blocks.rs
+++ b/azalea-block/src/generated.rs
@@ -1,20 +1,7 @@
-use std::any::Any;
-
-use crate::BlockBehavior;
+use crate::{Block, BlockBehavior, BlockState, BlockStates};
 use azalea_block_macros::make_block_states;
 use std::fmt::Debug;
 
-pub trait Block: Debug + Any {
-    fn behavior(&self) -> BlockBehavior;
-    fn id(&self) -> &'static str;
-    fn as_blockstate(&self) -> BlockState;
-}
-impl dyn Block {
-    pub fn downcast_ref<T: Block>(&self) -> Option<&T> {
-        (self as &dyn Any).downcast_ref::<T>()
-    }
-}
-
 make_block_states! {
     Properties => {
         "snowy" => bool,
diff --git a/azalea-block/src/lib.rs b/azalea-block/src/lib.rs
index 7a62e588..43099db5 100755
--- a/azalea-block/src/lib.rs
+++ b/azalea-block/src/lib.rs
@@ -2,14 +2,49 @@
 #![feature(trait_upcasting)]
 
 mod behavior;
-mod blocks;
+mod generated;
+mod range;
+
+pub use generated::{blocks, properties};
 
 use azalea_buf::{BufReadError, McBufReadable, McBufVarReadable, McBufVarWritable, McBufWritable};
 pub use behavior::BlockBehavior;
-pub use blocks::*;
-use std::io::{Cursor, Write};
+use core::fmt::Debug;
+pub use range::BlockStates;
+use std::{
+    any::Any,
+    io::{Cursor, Write},
+};
+
+pub trait Block: Debug + Any {
+    fn behavior(&self) -> BlockBehavior;
+    /// Get the Minecraft ID for this block. For example `stone` or
+    /// `grass_block`.
+    fn id(&self) -> &'static str;
+    /// Convert the block to a block state. This is lossless, as the block
+    /// contains all the state data.
+    fn as_block_state(&self) -> BlockState;
+}
+impl dyn Block {
+    pub fn downcast_ref<T: Block>(&self) -> Option<&T> {
+        (self as &dyn Any).downcast_ref::<T>()
+    }
+}
+
+/// A representation of a state a block can be in.
+///
+/// For example, a stone block only has one state but each possible stair
+/// rotation is a different state.
+#[derive(Copy, Clone, PartialEq, Eq, Default, Hash)]
+pub struct BlockState {
+    /// The protocol ID for the block state. IDs may change every
+    /// version, so you shouldn't hard-code them or store them in databases.
+    pub id: u32,
+}
 
 impl BlockState {
+    pub const AIR: BlockState = BlockState { id: 0 };
+
     /// Transmutes a u32 to a block state.
     ///
     /// # Safety
@@ -52,6 +87,17 @@ impl McBufWritable for BlockState {
     }
 }
 
+impl std::fmt::Debug for BlockState {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(
+            f,
+            "BlockState(id: {}, {:?})",
+            self.id,
+            Box::<dyn Block>::from(*self)
+        )
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -80,18 +126,14 @@ mod tests {
             "{:?}",
             BlockState::from(azalea_registry::Block::FloweringAzalea)
         );
-        assert!(
-            formatted.ends_with(", FloweringAzaleaBlock)"),
-            "{}",
-            formatted
-        );
+        assert!(formatted.ends_with(", FloweringAzalea)"), "{}", formatted);
 
         let formatted = format!(
             "{:?}",
             BlockState::from(azalea_registry::Block::BigDripleafStem)
         );
         assert!(
-            formatted.ends_with(", BigDripleafStemBlock { facing: North, waterlogged: false })"),
+            formatted.ends_with(", BigDripleafStem { facing: North, waterlogged: false })"),
             "{}",
             formatted
         );
diff --git a/azalea-block/src/range.rs b/azalea-block/src/range.rs
new file mode 100644
index 00000000..6ccf4152
--- /dev/null
+++ b/azalea-block/src/range.rs
@@ -0,0 +1,33 @@
+use std::{collections::HashSet, ops::RangeInclusive};
+
+use crate::BlockState;
+
+#[derive(Debug, Clone)]
+pub struct BlockStates {
+    pub set: HashSet<BlockState>,
+}
+
+impl From<RangeInclusive<u32>> for BlockStates {
+    fn from(range: RangeInclusive<u32>) -> Self {
+        let mut set = HashSet::with_capacity((range.end() - range.start() + 1) as usize);
+        for id in range {
+            set.insert(BlockState { id });
+        }
+        Self { set }
+    }
+}
+
+impl IntoIterator for BlockStates {
+    type Item = BlockState;
+    type IntoIter = std::collections::hash_set::IntoIter<BlockState>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.set.into_iter()
+    }
+}
+
+impl BlockStates {
+    pub fn contains(&self, state: &BlockState) -> bool {
+        self.set.contains(state)
+    }
+}
diff --git a/azalea-core/src/position.rs b/azalea-core/src/position.rs
index 5ba7143e..3c452d3a 100755
--- a/azalea-core/src/position.rs
+++ b/azalea-core/src/position.rs
@@ -12,6 +12,8 @@ macro_rules! vec3_impl {
                 Self { x, y, z }
             }
 
+            /// Get the distance of this vector to the origin by doing `x^2 + y^2 +
+            /// z^2`.
             pub fn length_sqr(&self) -> $type {
                 self.x * self.x + self.y * self.y + self.z * self.z
             }
@@ -139,6 +141,11 @@ impl BlockPos {
             z: self.z as f64 + 0.5,
         }
     }
+
+    /// Get the distance of this vector from the origin by doing `x + y + z`.
+    pub fn length_manhattan(&self) -> u32 {
+        (self.x.abs() + self.y.abs() + self.z.abs()) as u32
+    }
 }
 
 /// Chunk coordinates are used to represent where a chunk is in the world. You
@@ -148,12 +155,21 @@ pub struct ChunkPos {
     pub x: i32,
     pub z: i32,
 }
-
 impl ChunkPos {
     pub fn new(x: i32, z: i32) -> Self {
         ChunkPos { x, z }
     }
 }
+impl Add<ChunkPos> for ChunkPos {
+    type Output = Self;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        Self {
+            x: self.x + rhs.x,
+            z: self.z + rhs.z,
+        }
+    }
+}
 
 /// The coordinates of a chunk section in the world.
 #[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
diff --git a/azalea-physics/src/lib.rs b/azalea-physics/src/lib.rs
index e3954061..1736b8fb 100644
--- a/azalea-physics/src/lib.rs
+++ b/azalea-physics/src/lib.rs
@@ -467,8 +467,8 @@ mod tests {
             .id();
         let block_state = partial_world.chunks.set_block_state(
             &BlockPos { x: 0, y: 69, z: 0 },
-            azalea_block::StoneSlabBlock {
-                kind: azalea_block::Type::Bottom,
+            azalea_block::blocks::StoneSlab {
+                kind: azalea_block::properties::Type::Bottom,
                 waterlogged: false,
             }
             .into(),
@@ -521,8 +521,8 @@ mod tests {
             .id();
         let block_state = world_lock.write().chunks.set_block_state(
             &BlockPos { x: 0, y: 69, z: 0 },
-            azalea_block::StoneSlabBlock {
-                kind: azalea_block::Type::Top,
+            azalea_block::blocks::StoneSlab {
+                kind: azalea_block::properties::Type::Top,
                 waterlogged: false,
             }
             .into(),
@@ -574,11 +574,11 @@ mod tests {
             .id();
         let block_state = world_lock.write().chunks.set_block_state(
             &BlockPos { x: 0, y: 69, z: 0 },
-            azalea_block::CobblestoneWallBlock {
-                east: azalea_block::EastWall::Low,
-                north: azalea_block::NorthWall::Low,
-                south: azalea_block::SouthWall::Low,
-                west: azalea_block::WestWall::Low,
+            azalea_block::blocks::CobblestoneWall {
+                east: azalea_block::properties::EastWall::Low,
+                north: azalea_block::properties::NorthWall::Low,
+                south: azalea_block::properties::SouthWall::Low,
+                west: azalea_block::properties::WestWall::Low,
                 up: false,
                 waterlogged: false,
             }
@@ -636,11 +636,11 @@ mod tests {
                 y: 69,
                 z: -8,
             },
-            azalea_block::CobblestoneWallBlock {
-                east: azalea_block::EastWall::Low,
-                north: azalea_block::NorthWall::Low,
-                south: azalea_block::SouthWall::Low,
-                west: azalea_block::WestWall::Low,
+            azalea_block::blocks::CobblestoneWall {
+                east: azalea_block::properties::EastWall::Low,
+                north: azalea_block::properties::NorthWall::Low,
+                south: azalea_block::properties::SouthWall::Low,
+                west: azalea_block::properties::WestWall::Low,
                 up: false,
                 waterlogged: false,
             }
diff --git a/azalea-protocol/src/packets/game/clientbound_chunks_biomes_packet.rs b/azalea-protocol/src/packets/game/clientbound_chunks_biomes_packet.rs
new file mode 100644
index 00000000..9ad242a4
--- /dev/null
+++ b/azalea-protocol/src/packets/game/clientbound_chunks_biomes_packet.rs
@@ -0,0 +1,7 @@
+use azalea_protocol_macros::ClientboundGamePacket;
+use azalea_buf::McBuf;
+
+#[derive(Clone, Debug, McBuf, ClientboundGamePacket)]
+pub struct ClientboundChunksBiomesPacket {
+pub chunk_biome_data: todo!(),
+}
\ No newline at end of file
diff --git a/azalea-world/src/bit_storage.rs b/azalea-world/src/bit_storage.rs
index f6ca4cd6..09b68fae 100755
--- a/azalea-world/src/bit_storage.rs
+++ b/azalea-world/src/bit_storage.rs
@@ -158,13 +158,13 @@ impl BitStorage {
             .unwrap()
     }
 
+    /// Get the data at the given index.
+    ///
+    /// # Panics
+    ///
+    /// This function will panic if the given index is greater than or equal to
+    /// the size of this storage.
     pub fn get(&self, index: usize) -> u64 {
-        // Validate.inclusiveBetween(0L, (long)(this.size - 1), (long)var1);
-        // int var2 = this.cellIndex(var1);
-        // long var3 = this.data[var2];
-        // int var5 = (var1 - var2 * this.valuesPerLong) * this.bits;
-        // return (int)(var3 >> var5 & this.mask);
-
         assert!(
             index < self.size,
             "Index {} out of bounds (must be less than {})",
diff --git a/azalea-world/src/iterators.rs b/azalea-world/src/iterators.rs
new file mode 100644
index 00000000..53a94898
--- /dev/null
+++ b/azalea-world/src/iterators.rs
@@ -0,0 +1,247 @@
+//! Iterators for iterating over Minecraft blocks and chunks, based on
+//! [prismarine-world's iterators](https://github.com/PrismarineJS/prismarine-world/blob/master/src/iterators.js).
+
+use azalea_core::{BlockPos, ChunkPos};
+
+/// An octahedron iterator, useful for iterating over blocks in a world.
+///
+/// ```
+/// # use azalea_core::BlockPos;
+/// # use azalea_world::iterators::BlockIterator;
+///
+/// let mut iter = BlockIterator::new(BlockPos::default(), 4);
+/// for block_pos in iter {
+///    println!("{:?}", block_pos);
+/// }
+/// ```
+pub struct BlockIterator {
+    start: BlockPos,
+    max_distance: u32,
+
+    pos: BlockPos,
+    apothem: u32,
+    left: i32,
+    right: i32,
+}
+impl BlockIterator {
+    pub fn new(start: BlockPos, max_distance: u32) -> Self {
+        Self {
+            start,
+            max_distance,
+
+            pos: BlockPos {
+                x: -1,
+                y: -1,
+                z: -1,
+            },
+            apothem: 1,
+            left: 1,
+            right: 2,
+        }
+    }
+}
+
+impl Iterator for BlockIterator {
+    type Item = BlockPos;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.apothem > self.max_distance {
+            return None;
+        }
+
+        self.right -= 1;
+        if self.right < 0 {
+            self.left -= 1;
+            if self.left < 0 {
+                self.pos.z += 2;
+                if self.pos.z > 1 {
+                    self.pos.y += 2;
+                    if self.pos.y > 1 {
+                        self.pos.x += 2;
+                        if self.pos.x > 1 {
+                            self.apothem += 1;
+                            self.pos.x = -1;
+                        }
+                        self.pos.y = -1;
+                    }
+                    self.pos.z = -1;
+                }
+                self.left = self.apothem as i32;
+            }
+            self.right = self.left;
+        }
+        let x = self.pos.x * self.right;
+        let y = self.pos.y * ((self.apothem as i32) - self.left);
+        let z = self.pos.z * ((self.apothem as i32) - (i32::abs(x) + i32::abs(y)));
+        Some(BlockPos { x: x, y, z } + self.start)
+    }
+}
+
+/// A spiral iterator, useful for iterating over chunks in a world. Use
+/// `ChunkIterator` to sort by x+y+z (Manhattan) distance.
+///
+/// ```
+/// # use azalea_core::ChunkPos;
+/// # use azalea_world::iterators::SquareChunkIterator;
+///
+/// let mut iter = SquareChunkIterator::new(ChunkPos::default(), 4);
+/// for chunk_pos in iter {
+///   println!("{:?}", chunk_pos);
+/// }
+/// ```
+pub struct SquareChunkIterator {
+    start: ChunkPos,
+    number_of_points: u32,
+
+    dir: ChunkPos,
+
+    segment_len: u32,
+    pos: ChunkPos,
+    segment_passed: u32,
+    current_iter: u32,
+}
+impl SquareChunkIterator {
+    pub fn new(start: ChunkPos, max_distance: u32) -> Self {
+        Self {
+            start,
+            number_of_points: u32::pow(max_distance * 2 - 1, 2),
+
+            dir: ChunkPos { x: 1, z: 0 },
+
+            segment_len: 1,
+            pos: ChunkPos::default(),
+            segment_passed: 0,
+            current_iter: 0,
+        }
+    }
+
+    /// Change the distance that this iterator won't go past.
+    ///
+    /// ```
+    /// # use azalea_core::ChunkPos;
+    /// # use azalea_world::iterators::SquareChunkIterator;
+    ///
+    /// let mut iter = SquareChunkIterator::new(ChunkPos::default(), 2);
+    /// while let Some(chunk_pos) = iter.next() {
+    ///   println!("{:?}", chunk_pos);
+    /// }
+    /// iter.set_max_distance(4);
+    /// while let Some(chunk_pos) = iter.next() {
+    ///   println!("{:?}", chunk_pos);
+    /// }
+    /// ```
+    pub fn set_max_distance(&mut self, max_distance: u32) {
+        self.number_of_points = u32::pow(max_distance * 2 - 1, 2);
+    }
+}
+impl Iterator for SquareChunkIterator {
+    type Item = ChunkPos;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.current_iter > self.number_of_points {
+            return None;
+        }
+
+        let output = self.start + self.dir;
+
+        // make a step, add the direction to the current position
+        self.pos.x += self.dir.x;
+        self.pos.z += self.dir.z;
+        self.segment_passed += 1;
+
+        if self.segment_passed == self.segment_len {
+            // done with current segment
+            self.segment_passed = 0;
+
+            // rotate directions
+            (self.dir.x, self.dir.z) = (-self.dir.z, self.dir.x);
+
+            // increase segment length if necessary
+            if self.dir.z == 0 {
+                self.segment_len += 1;
+            }
+        }
+        self.current_iter += 1;
+        Some(output)
+    }
+}
+
+/// A diagonal spiral iterator, useful for iterating over chunks in a world.
+///
+/// ```
+/// # use azalea_core::ChunkPos;
+/// # use azalea_world::iterators::ChunkIterator;
+///
+/// let mut iter = ChunkIterator::new(ChunkPos::default(), 4);
+/// for chunk_pos in iter {
+///   println!("{:?}", chunk_pos);
+/// }
+/// ```
+pub struct ChunkIterator {
+    pub max_distance: u32,
+    pub start: ChunkPos,
+    pub pos: ChunkPos,
+    pub layer: i32,
+    pub leg: i32,
+}
+impl ChunkIterator {
+    pub fn new(start: ChunkPos, max_distance: u32) -> Self {
+        Self {
+            max_distance,
+            start,
+            pos: ChunkPos { x: 2, z: -1 },
+            layer: 1,
+            leg: -1,
+        }
+    }
+}
+impl Iterator for ChunkIterator {
+    type Item = ChunkPos;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match self.leg {
+            -1 => {
+                self.leg = 0;
+                return Some(self.start);
+            }
+            0 => {
+                if self.max_distance == 1 {
+                    return None;
+                }
+                self.pos.x -= 1;
+                self.pos.z += 1;
+                if self.pos.x == 0 {
+                    self.leg = 1;
+                }
+            }
+            1 => {
+                self.pos.x -= 1;
+                self.pos.z -= 1;
+                if self.pos.z == 0 {
+                    self.leg = 2;
+                }
+            }
+            2 => {
+                self.pos.x += 1;
+                self.pos.z -= 1;
+                if self.pos.x == 0 {
+                    self.leg = 3;
+                }
+            }
+            3 => {
+                self.pos.x += 1;
+                self.pos.z += 1;
+                if self.pos.z == 0 {
+                    self.pos.x += 1;
+                    self.leg = 0;
+                    self.layer += 1;
+                    if self.layer == self.max_distance as i32 {
+                        return None;
+                    }
+                }
+            }
+            _ => unreachable!(),
+        }
+        Some(self.start + self.pos)
+    }
+}
diff --git a/azalea-world/src/lib.rs b/azalea-world/src/lib.rs
index 1a419c3a..77498efd 100644
--- a/azalea-world/src/lib.rs
+++ b/azalea-world/src/lib.rs
@@ -7,6 +7,7 @@ mod bit_storage;
 mod chunk_storage;
 mod container;
 pub mod entity;
+pub mod iterators;
 pub mod palette;
 mod world;
 
diff --git a/azalea-world/src/palette.rs b/azalea-world/src/palette.rs
index d97f61a3..d10357ad 100755
--- a/azalea-world/src/palette.rs
+++ b/azalea-world/src/palette.rs
@@ -12,6 +12,11 @@ pub enum PalettedContainerType {
 #[derive(Clone, Debug)]
 pub struct PalettedContainer {
     pub bits_per_entry: u8,
+    /// This is usually a list of unique values that appear in the container so
+    /// they can be indexed by the bit storage.
+    ///
+    /// Sometimes it doesn't contain anything if there's too many unique items
+    /// in the bit storage, though.
     pub palette: Palette,
     /// Compacted list of indices pointing to entry IDs in the Palette.
     pub storage: BitStorage,
@@ -37,7 +42,7 @@ impl PalettedContainer {
         container_type: &'static PalettedContainerType,
     ) -> Result<Self, BufReadError> {
         let bits_per_entry = u8::read_from(buf)?;
-        let palette_type = PaletteType::from_bits_and_type(bits_per_entry, container_type);
+        let palette_type = PaletteKind::from_bits_and_type(bits_per_entry, container_type);
         let palette = palette_type.read(buf)?;
         let size = container_type.size();
 
@@ -57,15 +62,33 @@ impl PalettedContainer {
     }
 
     /// Calculates the index of the given coordinates.
-    pub fn get_index(&self, x: usize, y: usize, z: usize) -> usize {
+    pub fn index_from_coords(&self, x: usize, y: usize, z: usize) -> usize {
         let size_bits = self.container_type.size_bits();
 
         (((y << size_bits) | z) << size_bits) | x
     }
 
+    pub fn coords_from_index(&self, index: usize) -> (usize, usize, usize) {
+        let size_bits = self.container_type.size_bits();
+        let mask = (1 << size_bits) - 1;
+        (
+            index & mask,
+            (index >> size_bits >> size_bits) & mask,
+            (index >> size_bits) & mask,
+        )
+    }
+
     /// Returns the value at the given index.
+    ///
+    /// # Panics
+    ///
+    /// This function panics if the index is greater than or equal to the number
+    /// of things in the storage. (So for block states, it must be less than
+    /// 4096).
     pub fn get_at_index(&self, index: usize) -> u32 {
+        // first get the pallete id
         let paletted_value = self.storage.get(index);
+        // and then get the value from that id
         self.palette.value_for(paletted_value as usize)
     }
 
@@ -73,14 +96,14 @@ impl PalettedContainer {
     pub fn get(&self, x: usize, y: usize, z: usize) -> u32 {
         // let paletted_value = self.storage.get(self.get_index(x, y, z));
         // self.palette.value_for(paletted_value as usize)
-        self.get_at_index(self.get_index(x, y, z))
+        self.get_at_index(self.index_from_coords(x, y, z))
     }
 
     /// Sets the id at the given coordinates and return the previous id
     pub fn get_and_set(&mut self, x: usize, y: usize, z: usize, value: u32) -> u32 {
         let paletted_value = self.id_for(value);
         self.storage
-            .get_and_set(self.get_index(x, y, z), paletted_value as u64) as u32
+            .get_and_set(self.index_from_coords(x, y, z), paletted_value as u64) as u32
     }
 
     /// Sets the id at the given index and return the previous id. You probably
@@ -92,12 +115,12 @@ impl PalettedContainer {
 
     /// Sets the id at the given coordinates and return the previous id
     pub fn set(&mut self, x: usize, y: usize, z: usize, value: u32) {
-        self.set_at_index(self.get_index(x, y, z), value);
+        self.set_at_index(self.index_from_coords(x, y, z), value);
     }
 
     fn create_or_reuse_data(&self, bits_per_entry: u8) -> PalettedContainer {
         let new_palette_type =
-            PaletteType::from_bits_and_type(bits_per_entry, &self.container_type);
+            PaletteKind::from_bits_and_type(bits_per_entry, &self.container_type);
         // note for whoever is trying to optimize this: vanilla has this
         // but it causes a stack overflow since it's not changing the bits per entry
         // i don't know how to fix this properly so glhf
@@ -188,13 +211,14 @@ impl McBufWritable for PalettedContainer {
 }
 
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub enum PaletteType {
+pub enum PaletteKind {
     SingleValue,
     Linear,
     Hashmap,
     Global,
 }
 
+/// A representation of the different types of chunk palettes Minecraft uses.
 #[derive(Clone, Debug)]
 pub enum Palette {
     /// ID of the corresponding entry in its global palette
@@ -211,13 +235,7 @@ impl Palette {
         match self {
             Palette::SingleValue(v) => *v,
             Palette::Linear(v) => v[id],
-            Palette::Hashmap(v) => {
-                if id >= v.len() {
-                    0
-                } else {
-                    v[id]
-                }
-            }
+            Palette::Hashmap(v) => v.get(id).copied().unwrap_or_default(),
             Palette::Global => id as u32,
         }
     }
@@ -241,49 +259,49 @@ impl McBufWritable for Palette {
     }
 }
 
-impl PaletteType {
+impl PaletteKind {
     pub fn from_bits_and_type(bits_per_entry: u8, container_type: &PalettedContainerType) -> Self {
         match container_type {
             PalettedContainerType::BlockStates => match bits_per_entry {
-                0 => PaletteType::SingleValue,
-                1..=4 => PaletteType::Linear,
-                5..=8 => PaletteType::Hashmap,
-                _ => PaletteType::Global,
+                0 => PaletteKind::SingleValue,
+                1..=4 => PaletteKind::Linear,
+                5..=8 => PaletteKind::Hashmap,
+                _ => PaletteKind::Global,
             },
             PalettedContainerType::Biomes => match bits_per_entry {
-                0 => PaletteType::SingleValue,
-                1..=3 => PaletteType::Linear,
-                _ => PaletteType::Global,
+                0 => PaletteKind::SingleValue,
+                1..=3 => PaletteKind::Linear,
+                _ => PaletteKind::Global,
             },
         }
     }
 
     pub fn read(&self, buf: &mut Cursor<&[u8]>) -> Result<Palette, BufReadError> {
         Ok(match self {
-            PaletteType::SingleValue => Palette::SingleValue(u32::var_read_from(buf)?),
-            PaletteType::Linear => Palette::Linear(Vec::<u32>::var_read_from(buf)?),
-            PaletteType::Hashmap => Palette::Hashmap(Vec::<u32>::var_read_from(buf)?),
-            PaletteType::Global => Palette::Global,
+            PaletteKind::SingleValue => Palette::SingleValue(u32::var_read_from(buf)?),
+            PaletteKind::Linear => Palette::Linear(Vec::<u32>::var_read_from(buf)?),
+            PaletteKind::Hashmap => Palette::Hashmap(Vec::<u32>::var_read_from(buf)?),
+            PaletteKind::Global => Palette::Global,
         })
     }
 
     pub fn as_empty_palette(&self) -> Palette {
         match self {
-            PaletteType::SingleValue => Palette::SingleValue(0),
-            PaletteType::Linear => Palette::Linear(Vec::new()),
-            PaletteType::Hashmap => Palette::Hashmap(Vec::new()),
-            PaletteType::Global => Palette::Global,
+            PaletteKind::SingleValue => Palette::SingleValue(0),
+            PaletteKind::Linear => Palette::Linear(Vec::new()),
+            PaletteKind::Hashmap => Palette::Hashmap(Vec::new()),
+            PaletteKind::Global => Palette::Global,
         }
     }
 }
 
-impl From<&Palette> for PaletteType {
+impl From<&Palette> for PaletteKind {
     fn from(palette: &Palette) -> Self {
         match palette {
-            Palette::SingleValue(_) => PaletteType::SingleValue,
-            Palette::Linear(_) => PaletteType::Linear,
-            Palette::Hashmap(_) => PaletteType::Hashmap,
-            Palette::Global => PaletteType::Global,
+            Palette::SingleValue(_) => PaletteKind::SingleValue,
+            Palette::Linear(_) => PaletteKind::Linear,
+            Palette::Hashmap(_) => PaletteKind::Hashmap,
+            Palette::Global => PaletteKind::Global,
         }
     }
 }
@@ -313,14 +331,14 @@ mod tests {
         assert_eq!(palette_container.bits_per_entry, 0);
         assert_eq!(palette_container.get_at_index(0), 0);
         assert_eq!(
-            PaletteType::from(&palette_container.palette),
-            PaletteType::SingleValue
+            PaletteKind::from(&palette_container.palette),
+            PaletteKind::SingleValue
         );
         palette_container.set_at_index(0, 1);
         assert_eq!(palette_container.get_at_index(0), 1);
         assert_eq!(
-            PaletteType::from(&palette_container.palette),
-            PaletteType::Linear
+            PaletteKind::from(&palette_container.palette),
+            PaletteKind::Linear
         );
     }
 
@@ -359,4 +377,22 @@ mod tests {
         palette_container.set_at_index(16, 16); // 5 bits
         assert_eq!(palette_container.bits_per_entry, 5);
     }
+
+    #[test]
+    fn test_coords_from_index() {
+        let palette_container =
+            PalettedContainer::new(&PalettedContainerType::BlockStates).unwrap();
+
+        for x in 0..15 {
+            for y in 0..15 {
+                for z in 0..15 {
+                    assert_eq!(
+                        palette_container
+                            .coords_from_index(palette_container.index_from_coords(x, y, z)),
+                        (x, y, z)
+                    );
+                }
+            }
+        }
+    }
 }
diff --git a/azalea-world/src/world.rs b/azalea-world/src/world.rs
index 41d83082..5bb9b0b7 100644
--- a/azalea-world/src/world.rs
+++ b/azalea-world/src/world.rs
@@ -2,9 +2,12 @@ use crate::{
     entity::{
         EntityInfos, EntityUuid, LoadedBy, Local, MinecraftEntityId, PartialEntityInfos, WorldName,
     },
+    iterators::ChunkIterator,
+    palette::Palette,
     ChunkStorage, PartialChunkStorage, WorldContainer,
 };
-use azalea_core::ChunkPos;
+use azalea_block::{BlockState, BlockStates};
+use azalea_core::{BlockPos, ChunkPos};
 use bevy_ecs::{
     entity::Entity,
     query::{Changed, With, Without},
@@ -187,6 +190,76 @@ impl Instance {
     pub fn entity_by_id(&self, entity_id: &MinecraftEntityId) -> Option<Entity> {
         self.entity_by_id.get(entity_id).copied()
     }
+
+    /// Find the coordinates of a block in the world.
+    ///
+    /// Note that this is sorted by `x+y+z` and not `x^2+y^2+z^2`, for
+    /// optimization purposes.
+    pub fn find_block(
+        &self,
+        nearest_to: impl Into<BlockPos>,
+        block_states: &BlockStates,
+    ) -> Option<BlockPos> {
+        // iterate over every chunk in a 3d spiral pattern
+        // and then check the palette for the block state
+
+        let nearest_to: BlockPos = nearest_to.into();
+        let start_chunk: ChunkPos = (&nearest_to).into();
+        let iter = ChunkIterator::new(start_chunk, 32);
+
+        for chunk_pos in iter {
+            let chunk = self.chunks.get(&chunk_pos).unwrap();
+
+            let mut nearest_found_pos: Option<BlockPos> = None;
+            let mut nearest_found_distance = 0;
+
+            for (section_index, section) in chunk.read().sections.iter().enumerate() {
+                let maybe_has_block = match &section.states.palette {
+                    Palette::SingleValue(id) => block_states.contains(&BlockState { id: *id }),
+                    Palette::Linear(ids) => ids
+                        .iter()
+                        .any(|&id| block_states.contains(&BlockState { id })),
+                    Palette::Hashmap(ids) => ids
+                        .iter()
+                        .any(|&id| block_states.contains(&BlockState { id })),
+                    Palette::Global => true,
+                };
+                if !maybe_has_block {
+                    continue;
+                }
+
+                for i in 0..4096 {
+                    let block_state = section.states.get_at_index(i);
+                    let block_state = BlockState { id: block_state };
+
+                    if block_states.contains(&block_state) {
+                        let (section_x, section_y, section_z) = section.states.coords_from_index(i);
+                        let (x, y, z) = (
+                            chunk_pos.x * 16 + (section_x as i32),
+                            self.chunks.min_y + (section_index * 16) as i32 + section_y as i32,
+                            chunk_pos.z * 16 + (section_z as i32),
+                        );
+                        let this_block_pos = BlockPos { x, y, z };
+                        let this_block_distance = (nearest_to - this_block_pos).length_manhattan();
+                        // only update if it's closer
+                        if !nearest_found_pos.is_some()
+                            || this_block_distance < nearest_found_distance
+                        {
+                            nearest_found_pos = Some(this_block_pos);
+                            nearest_found_distance = this_block_distance;
+                        }
+                    }
+                }
+            }
+
+            // if we found the position, return it
+            if nearest_found_pos.is_some() {
+                return nearest_found_pos;
+            }
+        }
+
+        None
+    }
 }
 
 impl Debug for PartialWorld {
diff --git a/azalea/examples/testbot.rs b/azalea/examples/testbot.rs
index 7b7b32b0..a25b28e3 100644
--- a/azalea/examples/testbot.rs
+++ b/azalea/examples/testbot.rs
@@ -52,17 +52,17 @@ async fn main() -> anyhow::Result<()> {
     }
 
     loop {
-        // let e = SwarmBuilder::new()
-        //     .add_accounts(accounts.clone())
-        //     .set_handler(handle)
-        //     .set_swarm_handler(swarm_handle)
-        //     .join_delay(Duration::from_millis(1000))
-        //     .start("localhost")
-        //     .await;
-        let e = azalea::ClientBuilder::new()
+        let e = SwarmBuilder::new()
+            .add_accounts(accounts.clone())
             .set_handler(handle)
-            .start(Account::offline("bot"), "localhost")
+            .set_swarm_handler(swarm_handle)
+            .join_delay(Duration::from_millis(1000))
+            .start("localhost")
             .await;
+        // let e = azalea::ClientBuilder::new()
+        //     .set_handler(handle)
+        //     .start(Account::offline("bot"), "localhost")
+        //     .await;
         eprintln!("{e:?}");
     }
 }
@@ -140,6 +140,25 @@ async fn handle(mut bot: Client, event: Event, _state: State) -> anyhow::Result<
                     "lag" => {
                         std::thread::sleep(Duration::from_millis(1000));
                     }
+                    "findblock" => {
+                        let target_pos = bot.world().read().find_block(
+                            bot.component::<Position>(),
+                            &azalea_registry::Block::DiamondBlock.into(),
+                        );
+                        bot.chat(&format!("target_pos: {target_pos:?}",));
+                    }
+                    "gotoblock" => {
+                        let target_pos = bot.world().read().find_block(
+                            bot.component::<Position>(),
+                            &azalea_registry::Block::DiamondBlock.into(),
+                        );
+                        if let Some(target_pos) = target_pos {
+                            // +1 to stand on top of the block
+                            bot.goto(BlockPosGoal::from(target_pos.up(1)));
+                        } else {
+                            bot.chat("no diamond block found");
+                        }
+                    }
                     _ => {}
                 }
             }
diff --git a/azalea/examples/todo/README.md b/azalea/examples/todo/README.md
new file mode 100644
index 00000000..ab31cf22
--- /dev/null
+++ b/azalea/examples/todo/README.md
@@ -0,0 +1 @@
+These examples don't work yet and were only written to help design APIs. They will work in the future (probably with minor changes).
diff --git a/azalea/examples/craft_dig_straight_down.rs b/azalea/examples/todo/craft_dig_straight_down.rs
index 0632776e..4c980ccf 100755..100644
--- a/azalea/examples/craft_dig_straight_down.rs
+++ b/azalea/examples/todo/craft_dig_straight_down.rs
@@ -38,7 +38,7 @@ async fn handle(bot: Client, event: Event, state: State) -> anyhow::Result<()> {
                 bot.goto(pathfinder::Goals::NearXZ(5, azalea::BlockXZ(0, 0)))
                     .await;
                 let chest = bot
-                    .open_container(&bot.world().find_one_block(|b| b.id == "minecraft:chest"))
+                    .open_container(&bot.world().find_block(azalea_registry::Block::Chest))
                     .await
                     .unwrap();
                 bot.take_amount(&chest, 5, |i| i.id == "#minecraft:planks")
@@ -47,8 +47,7 @@ async fn handle(bot: Client, event: Event, state: State) -> anyhow::Result<()> {
 
                 let crafting_table = bot
                     .open_crafting_table(
-                        &bot.world
-                            .find_one_block(|b| b.id == "minecraft:crafting_table"),
+                        &bot.world.find_block(azalea_registry::Block::CraftingTable),
                     )
                     .await
                     .unwrap();
diff --git a/azalea/examples/mine_a_chunk.rs b/azalea/examples/todo/mine_a_chunk.rs
index 74ffacac..74ffacac 100644
--- a/azalea/examples/mine_a_chunk.rs
+++ b/azalea/examples/todo/mine_a_chunk.rs
diff --git a/azalea/examples/pvp.rs b/azalea/examples/todo/pvp.rs
index fb5a768d..fb5a768d 100755..100644
--- a/azalea/examples/pvp.rs
+++ b/azalea/examples/todo/pvp.rs