From 6b7681bad6b61a589cf34dc3e57503ee1087e89c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adrian=20Wo=C5=BAniak?= <adrian.wozniak@ita-prog.pl>
Date: Mon, 16 Sep 2024 12:32:01 +0200
Subject: [PATCH] Fix writter

---
 maze/src/lib.rs | 74 +++++++++++++++++++++++--------------------------
 1 file changed, 34 insertions(+), 40 deletions(-)

diff --git a/maze/src/lib.rs b/maze/src/lib.rs
index 269938d..59f6cfa 100644
--- a/maze/src/lib.rs
+++ b/maze/src/lib.rs
@@ -451,12 +451,22 @@ impl<const X: usize, const Y: usize, const SIZE: usize> AsciiBroad<X, Y, SIZE> {
     }
 }
 
-struct BufWriter<'s>(&'s mut [MazePart]);
+struct BufWriter<'s>(&'s mut [MazePart], usize);
 
 impl<'s> BufWriter<'s> {
+    pub fn new(b: &'s mut [MazePart]) -> Self {
+        Self(b, 0)
+    }
     pub fn push(&mut self, part: MazePart) {
-        self.0[0] = part;
-        self.0 = &mut self.0[1..];
+        self.0[self.1] = part;
+        self.1 += 1;
+    }
+    pub fn copy(&mut self, src: &[MazePart]) {
+        src.iter()
+            .take_while(|p| **p != MazePart::Noop)
+            .for_each(|p| {
+                self.push(*p);
+            });
     }
 }
 
@@ -464,22 +474,12 @@ pub struct BinaryMap<const X: usize, const Y: usize, const SIZE: usize>;
 
 impl<const X: usize, const Y: usize, const SIZE: usize> BinaryMap<X, Y, SIZE> {
     fn format(&self, grid: &Grid<X, Y, SIZE>, buffer: &mut [MazePart]) {
-        let push = |p: MazePart, buffer: &mut [MazePart]| {
-            buffer[0] = p;
-            &mut buffer[1..]
-        };
-        let copy = |src: &[MazePart], dst: &mut [MazePart]| {
-            src.iter()
-                .take_while(|p| **p != MazePart::Noop)
-                .for_each(|p| {
-                    dst = push(*p, dst);
-                });
-        };
+        let mut bw = BufWriter::new(buffer);
 
-        buffer = push(MazePart::Wall, buffer);
+        bw.push(MazePart::Wall);
         (0..X).into_iter().for_each(|_| {
-            push(MazePart::Wall, buffer);
-            push(MazePart::Wall, buffer);
+            bw.push(MazePart::Wall);
+            bw.push(MazePart::Wall);
         });
 
         let mut top_line = [MazePart::Noop; SIZE];
@@ -488,34 +488,28 @@ impl<const X: usize, const Y: usize, const SIZE: usize> BinaryMap<X, Y, SIZE> {
         for y in 0..Y {
             top_line.fill(MazePart::Noop);
             bottom_line.fill(MazePart::Noop);
-            let tl = &mut top_line;
-            let bl = &mut bottom_line;
+            let mut tl = BufWriter::new(&mut top_line);
+            let mut bl = BufWriter::new(&mut bottom_line);
 
-            push(MazePart::Wall, tl);
-            push(MazePart::Wall, bl);
+            tl.push(MazePart::Wall);
+            bl.push(MazePart::Wall);
 
             for x in 0..X {
-                push(MazePart::Passage, tl);
-                push(
-                    if grid.is_carved((x, y), Cell::EAST) {
-                        MazePart::Passage
-                    } else {
-                        MazePart::Wall
-                    },
-                    tl,
-                );
+                tl.push(MazePart::Passage);
+                tl.push(if grid.is_carved((x, y), Cell::EAST) {
+                    MazePart::Passage
+                } else {
+                    MazePart::Wall
+                });
 
-                push(
-                    if grid.is_carved((x, y), Cell::SOUTH) {
-                        MazePart::Passage
-                    } else {
-                        MazePart::Wall
-                    },
-                    bl,
-                );
+                bl.push(if grid.is_carved((x, y), Cell::SOUTH) {
+                    MazePart::Passage
+                } else {
+                    MazePart::Wall
+                });
             }
-            copy(&top_line, buffer);
-            copy(&bottom_line, buffer);
+            bw.copy(&top_line);
+            bw.copy(&bottom_line);
         }
     }
 }