Broken cz1 implementation

.gitignore

@@ -13,3 +13,5 @@ Cargo.lock
 *.cz*
 *.CZ*
 *.png
+
+test_files/*

src/cz_common.rs

@@ -5,7 +5,10 @@ use thiserror::Error;
 #[derive(Error, Debug)]
 pub enum CzError {
     #[error("Version in header does not match expected version")]
-    VersionMismatch
+    VersionMismatch,
+
+    #[error("Format of supplied file is incorrect")]
+    InvalidFormat,
 }
 
 pub trait CzHeader {
@@ -19,7 +22,7 @@ pub trait CzHeader {
 
     fn height(&self) -> u16;
 
-    fn depth(&self) -> u8;
+    fn depth(&self) -> u16;
 }
 
 /// The common first part of a header of a CZ# file
@@ -29,7 +32,7 @@ pub(crate) struct CommonHeader {
     pub version: u8,
 
     /// Length of the header in bytes
-    pub length: u8,
+    pub length: u32,
 
     /// Width of the image in pixels
     pub width: u16,
@@ -38,17 +41,17 @@ pub(crate) struct CommonHeader {
     pub height: u16,
 
     /// Bit depth in Bits Per Pixel (BPP)
-    pub depth: u8,
+    pub depth: u16,
 }
 
 impl CommonHeader {
     pub fn new(bytes: &[u8]) -> Self {
         Self {
             version: bytes[2] - b'0',
-            length: bytes[4],
+            length: u32::from_le_bytes(bytes[4..8].try_into().unwrap()),
             width: u16::from_le_bytes(bytes[8..10].try_into().unwrap()),
             height: u16::from_le_bytes(bytes[10..12].try_into().unwrap()),
-            depth: bytes[12],
+            depth: u16::from_le_bytes(bytes[12..14].try_into().unwrap()),
         }
     }
 }
@@ -68,3 +71,15 @@ pub trait CzImage {
     /// Get the raw underlying bitmap for an image
     fn raw_bitmap(&self) -> &Vec<u8>;
 }
+
+pub fn parse_colormap(input: &[u8], num_colors: usize) -> (Vec<[u8; 4]>, usize) {
+    let mut colormap = Vec::with_capacity(num_colors);
+
+    let input_iter = input.windows(4).step_by(4).take(num_colors);
+
+    for color in input_iter {
+        colormap.push(color.try_into().unwrap());
+    }
+
+    (colormap, num_colors * 4)
+}

src/formats/cz0.rs

@@ -75,7 +75,7 @@ impl CzHeader for Cz0Header {
         self.common.height
     }
 
-    fn depth(&self) -> u8 {
+    fn depth(&self) -> u16 {
         self.common.depth
     }
 }
@@ -88,7 +88,7 @@ impl CzImage for Cz0Image {
         let header = Cz0Header::new(bytes)?;
 
         // Get the rest of the file, which is the bitmap
-        let bitmap = bytes[header.header_length() as usize..].to_vec();
+        let bitmap = bytes[header.header_length()..].to_vec();
 
         Ok(Self {
             header,

src/formats/cz1.rs

@@ -0,0 +1,177 @@
+use std::io::Read;
+
+use crate::cz_common::{parse_colormap, CommonHeader, CzError, CzHeader, CzImage};
+
+#[derive(Debug)]
+pub struct Cz1Header {
+    /// Common CZ# header
+    common: CommonHeader,
+}
+
+#[derive(Debug)]
+pub struct Cz1Image {
+    header: Cz1Header,
+    bitmap: Vec<u8>,
+    palette: Vec<[u8; 4]>,
+}
+
+impl CzHeader for Cz1Header {
+    fn new(bytes: &[u8]) -> Result<Self, CzError> {
+        let common = CommonHeader::new(bytes);
+
+        if common.version != 1 {
+            return Err(CzError::VersionMismatch)
+        }
+
+        Ok(Self {
+            common,
+        })
+    }
+
+    fn version(&self) -> u8 {
+        self.common.version
+    }
+
+    fn header_length(&self) -> usize {
+        self.common.length as usize
+    }
+
+    fn width(&self) -> u16 {
+        self.common.width
+    }
+
+    fn height(&self) -> u16 {
+        self.common.height
+    }
+
+    fn depth(&self) -> u16 {
+        self.common.depth
+    }
+}
+
+impl CzImage for Cz1Image {
+    type Header = Cz1Header;
+
+    fn decode(bytes: &[u8]) -> Result<Self, CzError> {
+        let mut position = 0;
+
+        // Get the header from the input
+        let header = Cz1Header::new(bytes)?;
+        position += header.header_length();
+
+        // The color palette
+        let (palette, palette_length) = parse_colormap(&bytes[position..], 0x100);
+        position += palette_length;
+
+        dbg!(&bytes[position..position + 4]);
+
+        let parts_count = u32::from_le_bytes(bytes[position..position + 4].try_into().unwrap());
+        position += 4;
+        dbg!(parts_count);
+        let mut part_sizes = vec![0; parts_count as usize];
+        let mut total_size = 0;
+
+        for size in &mut part_sizes {
+            let part_size = u32::from_le_bytes(bytes[position..position + 4].try_into().unwrap()) * 2;
+            *size = part_size;
+            total_size += part_size;
+
+            dbg!(part_size);
+
+            position += 8;
+        }
+
+        if position + total_size as usize > bytes.len() {
+            return Err(CzError::InvalidFormat)
+        }
+
+        let mut m_dst = 0;
+        let bitmap = vec![0; 4882176];
+
+        let mut image = Self {
+            header,
+            bitmap,
+            palette
+        };
+
+        for size in part_sizes {
+            let part = &bytes[position..position + size as usize];
+            position += size as usize;
+
+            for j in (0..part.len()).step_by(2) {
+                let ctl = part[j + 1];
+
+                if ctl == 0 {
+                    image.bitmap[m_dst] = part[j];
+                    m_dst += 1;
+                } else {
+                    m_dst += image.copy_range(part, get_offset(part, j), m_dst);
+                }
+            }
+        }
+
+        Ok(image)
+    }
+
+    fn save_as_png(&self, name: &str) {
+        image::save_buffer(
+            name,
+            &self.bitmap,
+            self.header.common.width as u32,
+            self.header.common.height as u32,
+            image::ExtendedColorType::Rgba8
+        ).unwrap()
+    }
+
+    fn header(&self) -> &Self::Header {
+        &self.header
+    }
+
+    fn raw_bitmap(&self) -> &Vec<u8> {
+        &self.bitmap
+    }
+}
+
+fn get_offset(input: &[u8], src: usize) -> usize {
+    (((input[src] as usize) | (input[src+1] as usize) << 8) - 0x101) * 2
+}
+
+impl Cz1Image {
+    fn copy_range(&mut self, input: &[u8], src: usize, dst: usize) -> usize {
+        let mut dst = dst;
+        let start_pos = dst;
+
+        if input[src + 1] == 0 {
+            self.bitmap[dst] = input[src];
+            dst += 1;
+        } else if get_offset(input, src) == src {
+            self.bitmap[dst] = 0;
+            dst += 1;
+        } else {
+            dst += self.copy_range(input, get_offset(input, src), dst);
+        }
+
+        if input[src + 3] == 0 {
+            self.bitmap[dst] = input[src + 2];
+            dst += 1;
+        } else if get_offset(input, src + 2) == src {
+            self.bitmap[dst] = self.bitmap[start_pos];
+            dst += 1;
+        } else {
+            self.bitmap[dst] = copy_one(input, get_offset(input, src + 2));
+            dst += 1;
+        }
+
+        dst - start_pos
+    }
+}
+
+fn copy_one(input: &[u8], src: usize) -> u8 {
+    if input[src + 1] == 0 {
+        input[src]
+    } else if get_offset(input, src) == src {
+        0
+    } else {
+        copy_one(input, get_offset(input, src))
+    }
+}

src/main.rs

@@ -1,17 +1,18 @@
 pub mod cz_common;
 pub mod formats{
     pub mod cz0;
+    pub mod cz1;
 }
 
 // Generic tools
 use std::fs;
 
-use crate::{cz_common::CzImage, formats::cz0::Cz0Image};
+use crate::{cz_common::CzImage, formats::cz1::Cz1Image};
 
 fn main() {
-    let input = fs::read("../test_files/Old_TestFiles/EX_PT.CZ0").expect("Error, could not open image");
-    let cz0_file = Cz0Image::decode(&input).unwrap();
-    println!("{:#?}", cz0_file.header());
+    let input = fs::read("../test_files/x5a3bvy.cz1").expect("Error, could not open image");
+    let cz1_file = Cz1Image::decode(&input).unwrap();
+    println!("{:#?}", cz1_file.header());
 
-    cz0_file.save_as_png("test.png")
+    cz1_file.save_as_png("test.png")
 }