commit 9b3f7698b51dd3225f48f8c119cc358f1f2196c0
Author: yukirij <yukirij@yukiri.jp>
Date:   Wed Apr 26 22:13:32 2023 -0700

    Initialize project.

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..a1740ea
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "szun"
+version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..76b4d94
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "szun"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/project.code-workspace b/project.code-workspace
new file mode 100644
index 0000000..732b176
--- /dev/null
+++ b/project.code-workspace
@@ -0,0 +1,12 @@
+{
+	"folders": [
+		{
+			"path": "."
+		}
+	],
+	"settings": {
+		"rust-analyzer.linkedProjects": [
+			".\\Cargo.toml"
+		]
+	}
+}
\ No newline at end of file
diff --git a/src/bin/main.rs b/src/bin/main.rs
new file mode 100644
index 0000000..778d05a
--- /dev/null
+++ b/src/bin/main.rs
@@ -0,0 +1,7 @@
+fn main()
+{
+    let d = szun::Integer::from(-1);
+    let enc = d.encode();
+    
+    for b in enc { print!("{:02x}", b); } print!("\n");
+}
diff --git a/src/data/boolean.rs b/src/data/boolean.rs
new file mode 100644
index 0000000..8d842d1
--- /dev/null
+++ b/src/data/boolean.rs
@@ -0,0 +1,19 @@
+use crate::{Szun, Type};
+
+pub struct Boolean {
+    data:bool,
+}
+impl Boolean {
+    pub fn new() -> Szun
+    {
+        Szun::Boolean(false)
+    }
+
+    pub fn from(data:bool) -> Szun
+    {
+        Szun::Boolean(data)
+    }
+}
+impl Type for Boolean {
+    fn tag() -> u32 { 0x02 }
+}
diff --git a/src/data/integer.rs b/src/data/integer.rs
new file mode 100644
index 0000000..fc4484d
--- /dev/null
+++ b/src/data/integer.rs
@@ -0,0 +1,19 @@
+use crate::{Szun, Type};
+
+pub struct Integer {
+    data:i64,
+}
+impl Integer {
+    pub fn new() -> Szun
+    {
+        Szun::Integer(0)
+    }
+
+    pub fn from(data:i64) -> Szun
+    {
+        Szun::Integer(data)
+    }
+}
+impl Type for Integer {
+    fn tag() -> u32 { 0x11 }
+}
diff --git a/src/data/mod.rs b/src/data/mod.rs
new file mode 100644
index 0000000..2e054e6
--- /dev/null
+++ b/src/data/mod.rs
@@ -0,0 +1,4 @@
+mod null; pub use null::Null;
+mod boolean; pub use boolean::Boolean;
+mod natural; pub use natural::Natural;
+mod integer; pub use integer::Integer;
diff --git a/src/data/natural.rs b/src/data/natural.rs
new file mode 100644
index 0000000..4c7984b
--- /dev/null
+++ b/src/data/natural.rs
@@ -0,0 +1,19 @@
+use crate::{Szun, Type};
+
+pub struct Natural {
+    data:u64,
+}
+impl Natural {
+    pub fn new() -> Szun
+    {
+        Szun::Natural(0)
+    }
+
+    pub fn from(data:u64) -> Szun
+    {
+        Szun::Natural(data)
+    }
+}
+impl Type for Natural {
+    fn tag() -> u32 { 0x10 }
+}
diff --git a/src/data/null.rs b/src/data/null.rs
new file mode 100644
index 0000000..f020364
--- /dev/null
+++ b/src/data/null.rs
@@ -0,0 +1,11 @@
+use crate::{Szun, Type};
+
+pub struct Null { }
+impl Null {
+    pub fn new() -> Szun {
+        Szun::Null
+    }
+}
+impl Type for Null {
+    fn tag() -> u32 { 0x00 }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..83fe9e9
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,129 @@
+#![allow(dead_code)]
+
+mod util;
+mod template; use template::Type;
+mod data; pub use data::*;
+
+pub enum Szun {
+    Null,
+    Boolean(bool),
+    Natural(u64),
+    Integer(i64),
+    Decimal(f64),
+    Block(Vec<u8>),
+    String(String),
+    Set(Vec<Szun>),
+    Array(Vec<Szun>),
+    List(Vec<Szun>),
+    Sparse(Vec<Szun>),
+    Map(Vec<Szun>),
+    //Tree(Vec<Szun>),
+    //Graph(Vec<Szun>),
+    Enum(Vec<Szun>),
+    Selection(Vec<Szun>),
+    Record(Vec<Szun>),
+    Schema(Vec<Szun>),
+}
+impl Szun {
+    fn encode_parts(&self) -> (Vec<u32>, Vec<u8>)
+    {
+        let mut tags = Vec::<u32>::with_capacity(1);
+        let mut encoded = Vec::<u8>::with_capacity(64);
+
+        match self {
+            Self::Null => {
+                tags.push(Null::tag());
+            }
+            
+            Self::Boolean(_data) => {
+                tags.push(Boolean::tag());
+            }
+            
+            Self::Natural(data) => {
+                tags.push(Natural::tag());
+                encoded.append(&mut util::pack_natural(*data));
+            }
+            
+            Self::Integer(data) => {
+                tags.push(Integer::tag());
+                encoded.append(&mut &mut util::pack_integer(*data));
+            }
+
+            _ => {
+                tags.push(0);
+            }
+            
+            /*Self::Decimal(_data) => {
+                tag = Decimal::tag();
+            }
+            
+            Self::Block(_data) => {
+                tag = Block::tag();
+            }
+            
+            Self::String(_data) => {
+                tag = String::tag();
+            }
+            
+            Self::Set(_data) => {
+                tag = Set::tag();
+            }
+            
+            Self::Array(_data) => {
+                tag = Array::tag();
+            }
+            
+            Self::List(_data) => {
+                tag = List::tag();
+            }
+            
+            Self::Sparse(_data) => {
+                tag = Sparse::tag();
+            }
+            
+            Self::Map(_data) => {
+                tag = Map::tag();
+            }
+            
+            Self::Enum(_data) => {
+                tag = Enum::tag();
+            }
+            
+            Self::Selection(_data) => {
+                tag = Selection::tag();
+            }
+            
+            Self::Record(_data) => {
+                tag = Record::tag();
+            }
+
+            Self::Schema(_data) => {
+                tag = Schema::tag();
+            }*/
+        }
+
+        return (tags, encoded);
+    }
+
+    pub fn encode_data(&self) -> Vec<u8>
+    {
+        let (_, encoded) = self.encode_parts();
+        return encoded;
+    }
+
+    pub fn encode(&self) -> Vec<u8>
+    {
+        let (tags, data) = self.encode_parts();
+        let mut prefix = Vec::<u8>::with_capacity(16);
+
+        for tag in tags {
+            prefix.append(&mut util::pack_natural(tag as u64));
+        }
+
+        let mut encoded = Vec::<u8>::with_capacity(prefix.len() + data.len());
+        for b in prefix { encoded.push(b); }
+        for b in data { encoded.push(b); }
+
+        return encoded;
+    }
+}
diff --git a/src/template/mod.rs b/src/template/mod.rs
new file mode 100644
index 0000000..d92275a
--- /dev/null
+++ b/src/template/mod.rs
@@ -0,0 +1,3 @@
+pub trait Type {
+    fn tag() -> u32;
+}
diff --git a/src/util/mod.rs b/src/util/mod.rs
new file mode 100644
index 0000000..132d82f
--- /dev/null
+++ b/src/util/mod.rs
@@ -0,0 +1,123 @@
+fn pack_count_leading_ones(data:u8) -> usize
+{
+    (data == 0xff) as usize
+    + (data >= 0xfe) as usize
+    + (data >= 0xfc) as usize
+    + (data >= 0xf8) as usize
+    + (data >= 0xf0) as usize
+    + (data >= 0xe0) as usize
+    + (data >= 0xc0) as usize
+    + (data >= 0x80) as usize
+}
+
+fn pack_encode_size(data:u64, signed:bool) -> usize
+{
+    let sign_bit = signed as u32;
+    1 + (data >= 1 << (7 - sign_bit)) as usize
+    + (data >= 1 << (14 - sign_bit)) as usize
+    + (data >= 1 << (21 - sign_bit)) as usize
+    + (data >= 1 << (28 - sign_bit)) as usize
+    + (data >= 1 << (35 - sign_bit)) as usize
+    + (data >= 1 << (42 - sign_bit)) as usize
+    + (data >= 1 << (49 - sign_bit)) as usize
+    + (data >= 1 << (56 - sign_bit)) as usize
+    + (signed && data >= 1 << 63) as usize
+}
+
+fn pack_data(size:usize, data:u64, sign:bool) -> Vec<u8>
+{
+    let mut data = data;
+    let mut buffer :Vec<u8> = vec![0];
+    let mut header_size = size - 1;
+    let mut buffer_size = size;
+
+    if header_size >= 8 {
+        buffer.append(&mut pack_natural(header_size as u64));
+        buffer_size += buffer.len() - 1;
+        header_size = 8;
+    }
+    buffer.resize(buffer_size, 0);
+    buffer[0] = ((0xFF00 >> header_size) & 0xFF) as u8;
+
+    for i in 1..buffer_size + 1 {
+        buffer[buffer_size - i] |= (data & 0xFF) as u8;
+        data >>= 8;
+    }
+
+    if sign {
+        match header_size {
+            8 => { buffer[buffer_size - (size - 1)] |= 0x80; }
+            7 => { buffer[1] |= 0x80; }
+            _ => { buffer[0] |= 1 << 6 - header_size; }
+        }
+    }
+
+    return buffer;
+}
+
+pub fn pack_natural(data:u64) -> Vec<u8>
+{
+    pack_data(pack_encode_size(data, false), data, false)
+}
+
+pub fn pack_integer(data:i64) -> Vec<u8>
+{
+    let mut udata :u64 = data as u64;
+    let negative :bool = data < 0;
+    if negative { udata = !udata; }
+
+    pack_data(pack_encode_size(udata, true), udata, negative)
+}
+
+fn unpack_data(data:&Vec<u8>, index:&mut usize, signed:bool) -> u64
+{
+    let mut result :u64 = 0;
+    let mut negative = false;
+    if *index < data.len() {
+        let mut pack_size = pack_count_leading_ones(data[*index]);
+
+        if pack_size < 7 {
+            result = (((data[*index] as u64) << pack_size) & 0xFF) >> pack_size;
+            if signed {
+                let sign_mask = 1 << (6 - pack_size);
+                println!("data: {}, mask: {}", result, sign_mask);
+                negative = (result & sign_mask) != 0;
+                result &= !sign_mask;
+            }
+            *index += 1;
+        }
+        else {
+            *index += 1;
+            if pack_size == 8 {
+                pack_size = unpack_natural(&data, index) as usize;
+            }
+            pack_size -= 1;
+
+            result = data[*index] as u64;
+            if signed {
+                negative = (result & 0x80) != 0;
+                result &= 0x7F;
+            }
+            *index += 1;
+        }
+
+        for _ in 1..pack_size + 1 {
+            result <<= 8;
+            result += data[*index] as u64;
+            *index += 1;
+        }
+
+        if negative { result = !result; }
+    }
+    return result;
+}
+
+pub fn unpack_natural(data:&Vec<u8>, index:&mut usize) -> u64
+{
+    unpack_data(data, index, false)
+}
+
+pub fn unpack_integer(data:&Vec<u8>, index:&mut usize) -> i64
+{
+    unpack_data(data, index, true) as i64
+}