implement FString for ANSI and WCS2 (UTF-16 1251) encodings

Cargo.lock

@@ -20,6 +20,12 @@ version = "1.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
 [[package]]
 name = "deflate"
 version = "1.0.0"
@@ -29,6 +35,15 @@ dependencies = [
  "adler32",
 ]
 
+[[package]]
+name = "encoding_rs"
+version = "0.8.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7268b386296a025e474d5140678f75d6de9493ae55a5d709eeb9dd08149945e1"
+dependencies = [
+ "cfg-if",
+]
+
 [[package]]
 name = "fot-save-edit"
 version = "0.1.0"
@@ -36,6 +51,7 @@ dependencies = [
  "anyhow",
  "byteorder",
  "deflate",
+ "encoding_rs",
  "inflate",
  "memmem",
 ]

Cargo.toml

@@ -9,5 +9,6 @@ edition = "2021"
 anyhow = "1.0.75"
 byteorder = "1.4.3"
 deflate = "1.0.0"
+encoding_rs = "0.8.33"
 inflate = "0.4.5"
 memmem = "0.1.1"

src/fot/fstring.rs

@@ -0,0 +1,63 @@
+use super::decoder::Decoder;
+use super::raw::Raw;
+use anyhow::Result;
+use std::io::Cursor;
+use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
+use encoding_rs::WINDOWS_1251;
+use std::str;
+
+// FString - Fallout String
+
+#[derive(Debug, PartialEq)]
+pub enum FStringEncoding {
+    ANSI,
+    WCS2
+}
+
+#[derive(Debug)]
+pub struct FString {
+    encoding: FStringEncoding,
+    str: String
+}
+
+impl Decoder for FString {
+    fn decode(raw: &Raw, offset: usize, _: usize) -> Result<Self> {
+        let mut rdr = Cursor::new(&raw.mem[offset..]);
+        let flen = rdr.read_u32::<LittleEndian>()? as usize;
+        let len = flen ^ (1<<31);
+        let start = offset + 4;
+        if flen & (1<<31) == 0 { // ANSI
+            let str = str::from_utf8(&raw.mem[start..start+len])?;
+            Ok(FString { encoding: FStringEncoding::ANSI, str: str.to_string() })
+        } else { // WCS2
+            let chars: Vec<u8> = raw.mem[start..start+len*2]
+                .iter().step_by(2).copied().collect();
+            let (str, _, _) = WINDOWS_1251.decode(&chars);
+            Ok(FString { encoding: FStringEncoding::WCS2, str: str.to_string() })
+        }
+    }
+
+    fn encode(&self) -> Raw {
+        let mut buf = vec![0u8, 4];
+        let mut wdr = Cursor::new(&mut buf[..]);
+        if self.encoding == FStringEncoding::ANSI {
+            let _ = wdr.write_u32::<LittleEndian>(self.str.len() as u32 ^ (1<<31));
+            buf.append(&mut self.str.clone().into_bytes());
+        } else { // WCS2
+            let _ = wdr.write_u32::<LittleEndian>(self.str.len() as u32 | (1<<31));
+            let (chars, _, _) = WINDOWS_1251.encode(self.str.as_str());
+            for &c in chars.iter() {
+                buf.push(c);
+                buf.push(0);
+            }
+        };
+        Raw { offset: 0, size: buf.len(), mem: buf }
+    }
+
+    fn get_enc_size(&self) -> usize {
+        match self.encoding {
+            FStringEncoding::ANSI => 4 + self.str.len(),
+            FStringEncoding::WCS2 => 4 + self.str.len() * 2
+        }
+    }
+}

src/fot/world.rs

@@ -1,6 +1,7 @@
 use super::decoder::Decoder;
 use super::raw::Raw;
 use super::tag::Tag;
+use super::fstring::FString;
 use anyhow::anyhow;
 use anyhow::Result;
 use std::io::Cursor;
@@ -19,6 +20,13 @@ pub struct World {
 impl World {
     const WORLD_TAG_LEN: usize = 11;
     const WORLD_HDR_LEN: usize = 0x13;
+
+    pub fn test(&self) -> Result<()> {
+        let a = FString::decode(&self.data, 0xF6, 0)?;
+        dbg!(&a);
+
+        Ok(())
+    }
 }
 
 impl Decoder for World {

src/main.rs

@@ -14,5 +14,6 @@ fn main() {
     
     
     let save = Save::load(Path::new(save_path)).expect("load save");
-    save.save(Path::new("out.sav")).expect("failed to save");
+    save.world.test().expect("test");
+    //save.save(Path::new("out.sav")).expect("failed to save");
 }