From 80e10e4e91caf979afa634bad3d581bfc73bb3a8 Mon Sep 17 00:00:00 2001
From: crumblingstatue <radiantstatue@gmail.com>
Date: Fri, 14 Apr 2023 17:42:22 +0200
Subject: [PATCH] Factor out single chunk saving code into a function

---
 src/world.rs | 98 +++++++++++++++++++++++++++-------------------------
 1 file changed, 51 insertions(+), 47 deletions(-)

diff --git a/src/world.rs b/src/world.rs
index a91802e..4aab436 100644
--- a/src/world.rs
+++ b/src/world.rs
@@ -91,57 +91,61 @@ impl World {
     }
     pub fn save_chunks(&self) {
         for (pos, chk) in self.chunks.iter() {
-            let reg_file_name = format_reg_file_name(pos.region());
-            dbg!(&reg_file_name);
-            let reg_file_exists = Path::new(&reg_file_name).exists();
-            if !reg_file_exists {
-                log::warn!("Region file doesn't exist. Going to create one.");
-            }
-            let mut f = OpenOptions::new()
-                .read(true)
-                .write(true)
-                .create(true)
-                .open(&reg_file_name)
-                .unwrap();
-            let mut existence_bitset = if reg_file_exists {
-                ExistenceBitset::read_from_file(&mut f)
-            } else {
-                ExistenceBitset::EMPTY
-            };
-            dbg!(existence_bitset);
-            let _ = dbg!(f.stream_position());
-            let mut region_tile_data = if reg_file_exists {
-                zstd::decode_all(&mut f).unwrap()
-            } else {
-                vec![0; REGION_BYTES]
-            };
-            // Even the zstd decompressed data should be exactly REGION_BYTES size
-            assert_eq!(region_tile_data.len(), REGION_BYTES);
-            let (loc_x, loc_y) = pos.local();
-            dbg!(loc_x, loc_y);
-            let loc_idx = loc_idx(loc_y, loc_x);
-            crate::bitmanip::set_nth_bit(&mut existence_bitset.0, loc_idx as usize, true);
-            let byte_idx = loc_byte_idx(loc_idx);
-            dbg!(byte_idx);
-            let end_idx = byte_idx + CHUNK_BYTES;
-            dbg!(end_idx);
-            for (i, tile) in chk.tiles.iter().enumerate() {
-                let off = byte_idx + (i * TILE_BYTES);
-                region_tile_data[off..off + 2].copy_from_slice(&tile.bg.to_le_bytes());
-                region_tile_data[off + 2..off + 4].copy_from_slice(&tile.mid.to_le_bytes());
-                region_tile_data[off + 4..off + 6].copy_from_slice(&tile.fg.to_le_bytes());
-            }
-            f.seek(SeekFrom::Start(0)).unwrap();
-            f.write_all(&u64::to_le_bytes(existence_bitset.0)[..])
-                .unwrap();
-            assert_eq!(f.stream_position().unwrap(), 8);
-            assert_eq!(region_tile_data.len(), REGION_BYTES);
-            let result = f.write_all(&zstd::encode_all(&region_tile_data[..], COMP_LEVEL).unwrap());
-            log::info!("{result:?}");
+            save_chunk(pos, chk);
         }
     }
 }
 
+fn save_chunk(pos: &ChunkPos, chk: &Chunk) {
+    let reg_file_name = format_reg_file_name(pos.region());
+    dbg!(&reg_file_name);
+    let reg_file_exists = Path::new(&reg_file_name).exists();
+    if !reg_file_exists {
+        log::warn!("Region file doesn't exist. Going to create one.");
+    }
+    let mut f = OpenOptions::new()
+        .read(true)
+        .write(true)
+        .create(true)
+        .open(&reg_file_name)
+        .unwrap();
+    let mut existence_bitset = if reg_file_exists {
+        ExistenceBitset::read_from_file(&mut f)
+    } else {
+        ExistenceBitset::EMPTY
+    };
+    dbg!(existence_bitset);
+    let _ = dbg!(f.stream_position());
+    let mut region_tile_data = if reg_file_exists {
+        zstd::decode_all(&mut f).unwrap()
+    } else {
+        vec![0; REGION_BYTES]
+    };
+    // Even the zstd decompressed data should be exactly REGION_BYTES size
+    assert_eq!(region_tile_data.len(), REGION_BYTES);
+    let (loc_x, loc_y) = pos.local();
+    dbg!(loc_x, loc_y);
+    let loc_idx = loc_idx(loc_y, loc_x);
+    crate::bitmanip::set_nth_bit(&mut existence_bitset.0, loc_idx as usize, true);
+    let byte_idx = loc_byte_idx(loc_idx);
+    dbg!(byte_idx);
+    let end_idx = byte_idx + CHUNK_BYTES;
+    dbg!(end_idx);
+    for (i, tile) in chk.tiles.iter().enumerate() {
+        let off = byte_idx + (i * TILE_BYTES);
+        region_tile_data[off..off + 2].copy_from_slice(&tile.bg.to_le_bytes());
+        region_tile_data[off + 2..off + 4].copy_from_slice(&tile.mid.to_le_bytes());
+        region_tile_data[off + 4..off + 6].copy_from_slice(&tile.fg.to_le_bytes());
+    }
+    f.seek(SeekFrom::Start(0)).unwrap();
+    f.write_all(&u64::to_le_bytes(existence_bitset.0)[..])
+        .unwrap();
+    assert_eq!(f.stream_position().unwrap(), 8);
+    assert_eq!(region_tile_data.len(), REGION_BYTES);
+    let result = f.write_all(&zstd::encode_all(&region_tile_data[..], COMP_LEVEL).unwrap());
+    log::info!("{result:?}");
+}
+
 fn loc_byte_idx_xy(x: u8, y: u8) -> usize {
     loc_byte_idx(loc_idx(y, x))
 }