From 19b3acc0e9c64acd81c136186e6939984b01806e Mon Sep 17 00:00:00 2001
From: ethaniccc <schooldocumentsandstuff@gmail.com>
Date: Tue, 9 Jan 2024 15:59:02 +0000
Subject: [PATCH] chunk.go: add Equals()

---
 server/world/chunk/chunk.go     | 36 +++++++++++++++++++++++++++++++++
 server/world/chunk/sub_chunk.go | 32 +++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)

diff --git a/server/world/chunk/chunk.go b/server/world/chunk/chunk.go
index c3412f5c7..0e249fa0a 100644
--- a/server/world/chunk/chunk.go
+++ b/server/world/chunk/chunk.go
@@ -1,6 +1,8 @@
 package chunk
 
 import (
+	"slices"
+
 	"github.com/df-mc/dragonfly/server/block/cube"
 )
 
@@ -42,6 +44,40 @@ func New(air uint32, r cube.Range) *Chunk {
 	}
 }
 
+// Equals returns if the chunk passed is equal to the current one
+func (chunk *Chunk) Equals(c *Chunk) bool {
+	if c.r != chunk.r {
+		return false
+	}
+
+	if c.air != chunk.air {
+		return false
+	}
+
+	if c.recalculateHeightMap != chunk.recalculateHeightMap {
+		return false
+	}
+
+	if !slices.Equal(c.heightMap, chunk.heightMap) {
+		return false
+	}
+
+	if len(c.sub) != len(chunk.sub) {
+		return false
+	}
+
+	for i := 0; i < len(c.sub); i++ {
+		c1 := c.sub[i]
+		c2 := chunk.sub[i]
+
+		if !c1.Equals(c2) {
+			return false
+		}
+	}
+
+	return true
+}
+
 // Range returns the cube.Range of the Chunk as passed to New.
 func (chunk *Chunk) Range() cube.Range {
 	return chunk.r
diff --git a/server/world/chunk/sub_chunk.go b/server/world/chunk/sub_chunk.go
index aee76ae11..3aafab649 100644
--- a/server/world/chunk/sub_chunk.go
+++ b/server/world/chunk/sub_chunk.go
@@ -1,5 +1,7 @@
 package chunk
 
+import "slices"
+
 // SubChunk is a cube of blocks located in a chunk. It has a size of 16x16x16 blocks and forms part of a stack
 // that forms a Chunk.
 type SubChunk struct {
@@ -14,6 +16,36 @@ func NewSubChunk(air uint32) *SubChunk {
 	return &SubChunk{air: air}
 }
 
+// Equals returns if the sub chunk passed is equal to the current one.
+func (sub *SubChunk) Equals(s *SubChunk) bool {
+	if s.air != sub.air {
+		return false
+	}
+
+	if !slices.Equal(s.blockLight, sub.blockLight) {
+		return false
+	}
+
+	if !slices.Equal(s.skyLight, sub.skyLight) {
+		return false
+	}
+
+	if len(s.storages) != len(sub.storages) {
+		return false
+	}
+
+	for i := 0; i < len(s.storages); i++ {
+		s1 := s.storages[i]
+		s2 := sub.storages[i]
+
+		if !s1.Equal(s2) {
+			return false
+		}
+	}
+
+	return true
+}
+
 // Empty checks if the SubChunk is considered empty. This is the case if the SubChunk has 0 block storages or if it has
 // a single one that is completely filled with air.
 func (sub *SubChunk) Empty() bool {