Move string encoding/decoding into world parser

src/encoding.rs

@@ -30,16 +30,34 @@ pub fn decode_multiline(input: &[u8]) -> String {
         .collect()
 }
 
+pub fn encode_oneline(input: &str) -> Result<Vec<u8>> {
+    input
+        .chars()
+        .map(|c| {
+            CP437_WINGDINGS
+                .encode(c)
+                .ok_or(anyhow!("Couldn't encode char: {}", c))
+        })
+        .collect()
+}
+
+pub fn decode_oneline(input: &[u8]) -> String {
+    input.iter().map(|&x| CP437_WINGDINGS.decode(x)).collect()
+}
+
 #[cfg(test)]
 mod tests {
+    use super::*;
     use insta::assert_debug_snapshot;
 
-    use crate::encoding::{decode_multiline, encode_multiline};
-
     fn serialize_code(input: &str) -> Vec<u8> {
         encode_multiline(input).expect("Error in test")
     }
 
+    fn serialize_title(input: &str) -> Vec<u8> {
+        encode_oneline(input).expect("Error in test")
+    }
+
     #[test]
     fn roundtrip_multiline() {
         let bytes: Vec<u8> = (0..=255).collect();
@@ -47,7 +65,13 @@ mod tests {
     }
 
     #[test]
-    fn newlines() {
+    fn roundtrip_oneline() {
+        let bytes: Vec<u8> = (0..=255).collect();
+        assert_eq!(bytes, serialize_title(&decode_oneline(&bytes)))
+    }
+
+    #[test]
+    fn newlines_to_cr() {
         assert_debug_snapshot!(serialize_code("ABC\nDEF"), @r###"
         [
             65,
@@ -61,6 +85,16 @@ mod tests {
         "###)
     }
 
+    #[test]
+    fn byte_13_to_wingding() {
+        // Code is allowed to have newlines
+        let bytes = serialize_code("ABC\nDEF");
+        assert!(bytes.contains(&13));
+
+        // But in a board title, that same byte is a wingding
+        assert_debug_snapshot!(decode_oneline(&bytes), @r#""ABC♪DEF""#);
+    }
+
     #[test]
     fn wingdings() {
         assert_debug_snapshot!(decode_multiline(&(0..32).collect::<Vec<_>>()), @r###""\0☺☻♥♦♣♠•◘○◙♂♀\n♫☼►◄↕‼¶§▬↨↑↓→←∟↔▲▼""###);

src/main.rs

@@ -4,15 +4,10 @@ mod preprocess;
 mod world;
 
 use anyhow::anyhow;
-use encoding::{decode_multiline, encode_multiline};
 use preprocess::eval::Context;
 use std::{env, error::Error, fs, path::PathBuf, process::exit};
 use world::World;
 
-fn to_latin1(bytes: &[u8]) -> String {
-    bytes.iter().map(|&x| x as char).collect()
-}
-
 fn main() -> Result<(), Box<dyn Error>> {
     let args: Vec<String> = env::args().collect();
     if args.len() != 2 {
@@ -33,7 +28,7 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     println!("num boards: {}", &world.boards.len());
     for board in &mut world.boards {
-        println!("board: {}", to_latin1(&board.name));
+        println!("board: {}", board.name);
         for stat in &mut board.stats {
             // Print some of the data parsed.
             let (x, y) = (stat.x as usize, stat.y as usize);
@@ -43,19 +38,12 @@ fn main() -> Result<(), Box<dyn Error>> {
                 let terrain_index = (x - 1) + (y - 1) * 60;
                 Some(board.terrain[terrain_index])
             };
-            println!(
-                "  stat at ({}, {}): {:?}, {:?}",
-                x,
-                y,
-                terrain,
-                to_latin1(&stat.code)
-            );
+            println!("  stat at ({}, {}): {:?}, {:?}", x, y, terrain, stat.code);
 
             // Evaluate macros
-            let old_code = decode_multiline(&stat.code);
-            let new_code = eval_context.eval_program(&old_code)?;
-            stat.code = encode_multiline(&new_code)?;
+            stat.code = eval_context.eval_program(&stat.code)?;
         }
+        board.name.push_str(" (♪)");
     }
 
     // Try to write a modified world file

src/world.rs

@@ -10,6 +10,8 @@ use nom::{
     sequence::tuple,
 };
 
+use crate::encoding::{decode_multiline, decode_oneline, encode_multiline, encode_oneline};
+
 #[derive(Debug)]
 pub struct LoadError {
     message: String,
@@ -87,7 +89,7 @@ pub struct World {
 }
 
 pub struct Board {
-    pub name: Vec<u8>,
+    pub name: String,
     pub terrain: Vec<[u8; 2]>,
     pub max_shots: u8,
     pub is_dark: bool,
@@ -118,7 +120,7 @@ pub struct Stat {
     pub under_color: u8,
     pub instruction_pointer: i16,
     pub bind_index: i16,
-    pub code: Vec<u8>,
+    pub code: String,
 }
 
 impl World {
@@ -201,7 +203,8 @@ impl Board {
         let (input, _) = le_u16.parse(bytes)?;
 
         // Read board name
-        let (input, name) = pstring(50)(input)?;
+        let (input, name_bytes) = pstring(50)(input)?;
+        let name = decode_oneline(&name_bytes);
 
         // Read terrain
         const NUM_TILES: usize = 60 * 25;
@@ -256,7 +259,8 @@ impl Board {
     pub fn to_bytes(&self) -> Result<Vec<u8>, &'static str> {
         let mut result = vec![];
         result.push_padding(2); // reserve space for board size
-        result.push_string(50, &self.name)?;
+        let name_bytes = encode_oneline(&self.name).unwrap();
+        result.push_string(50, &name_bytes)?;
 
         // Encode terrain
         if self.terrain.len() != 1500 {
@@ -315,7 +319,8 @@ impl Stat {
         let (input, _) = take(4usize)(input)?;
         let (input, (instruction_pointer, length)) = tuple((le_i16, le_i16))(input)?;
         let (input, _) = take(8usize)(input)?;
-        let (input, code) = take(0.max(length) as usize)(input)?;
+        let (input, code_bytes) = take(0.max(length) as usize)(input)?;
+        let code = decode_multiline(&code_bytes);
         Ok((
             input,
             Stat {
@@ -333,7 +338,7 @@ impl Stat {
                 under_color,
                 instruction_pointer,
                 bind_index: 0.min(length),
-                code: Vec::from(code),
+                code,
             },
         ))
     }
@@ -363,7 +368,8 @@ impl Stat {
         result.push_padding(8);
         if self.bind_index >= 0 {
             // TODO: more safety around bind-index XOR code
-            result.extend_from_slice(&self.code);
+            let code_bytes = encode_multiline(&self.code).unwrap();
+            result.extend_from_slice(&code_bytes);
         }
         result
     }