From df9471c74b0a1e156efafb31d41065925937ed24 Mon Sep 17 00:00:00 2001
From: shenjack <3695888@qq.com>
Date: Sat, 5 Aug 2023 12:11:06 +0800
Subject: [PATCH] =?UTF-8?q?=E5=90=88=E7=90=86=EF=BC=8C=E5=A4=AA=E5=90=88?=
 =?UTF-8?q?=E7=90=86=E4=BA=86?=
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---
 src/read.rs | 116 ++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 112 insertions(+), 4 deletions(-)

diff --git a/src/read.rs b/src/read.rs
index 4115def..0cf2574 100644
--- a/src/read.rs
+++ b/src/read.rs
@@ -61,7 +61,7 @@ pub mod read {
 
     /// 直接读取长度和值 不带名称
     /// 主要是为了可以直接递归 (
-    pub fn read_nbt_list(value: &mut Reader) -> Vec<NbtItem> {
+    pub fn from_nbt_list(value: &mut Reader) -> Vec<NbtItem> {
         // 读取长度
         let mut buff = [0_u8; 4];
         _ = value.read(&mut buff).unwrap();
@@ -122,7 +122,7 @@ pub mod read {
                 // 要命 (虽说没 Compound 那么麻烦)
                 // 直接递归就行
                 for _ in 0..len {
-                    vec.push(NbtItem::from(read_nbt_list(value)));
+                    vec.push(NbtItem::from(from_nbt_list(value)));
                 }
             }
             [0x0A] => {
@@ -157,13 +157,121 @@ pub mod read {
         }
         vec
     }
+
+    /// 直接读取长度和值 不带名称
+    /// 只不过 Compound 不带长度，得自己试
+    pub fn from_compound(value: &mut Reader) -> NbtList {
+        // 进来直接是 values
+        // loop 读取长度 name len name value value
+        // 直到一个 NbtEnd
+        let mut map: HashMap<Arc<str>, NbtItem> = HashMap::new();
+        loop {
+            let mut type_tag = [0_u8; 1];
+            _ = value.read(&mut type_tag).unwrap();
+            if type_tag == [0x00] {
+                // NbtEnd
+                break;
+            }
+            // 读取 name
+            // 直接调之前的方法读
+            let name = NbtValue::from_string(value).as_string().unwrap();
+            // 读取 value
+            let nbt_value: NbtItem = match type_tag {
+                [0x01] => NbtItem::Value(NbtValue::from_bool(value)),
+                [0x02] => NbtItem::Value(NbtValue::from_i16(value)),
+                [0x03] => NbtItem::Value(NbtValue::from_i32(value)),
+                [0x04] => NbtItem::Value(NbtValue::from_i64(value)),
+                [0x05] => NbtItem::Value(NbtValue::from_f32(value)),
+                [0x06] => NbtItem::Value(NbtValue::from_f64(value)),
+                [0x07] => NbtItem::from(from_bool_array(value)),
+                [0x08] => NbtItem::Value(NbtValue::from_string(value)),
+                [0x09] => NbtItem::from(from_nbt_list(value)),
+                [0x0A] => NbtItem::from(from_compound(value)),
+                [0x0B] => NbtItem::from(from_i32_array(value)),
+                [0x0C] => NbtItem::from(from_i64_array(value)),
+                _ => {
+                    panic!(
+                        "{}",
+                        format!(
+                            "WTF while reading Nbt Compound \ntype: {:?}\nreader pos: {:?}\nname: {:?}",
+                            type_tag,
+                            value.position(),
+                            name
+                        )
+                    )
+                }
+            };
+            // 读取完了，放进去
+            map.insert(name, nbt_value);
+        }
+        NbtList::from(map)
+    }
+}
+
+pub enum NbtStatus {
+    /// 读取到了 NbtEnd
+    End,
+    /// 继续中
+    Going(NbtItem),
+    /// 读取错误
+    Error(std::io::Error),
 }
 
 /// NbtItem
 /// 完整的读取逻辑就在这里了
 /// 来力
 #[allow(unused)]
-impl From<Cursor<&[u8]>> for NbtItem {
+impl TryFrom<Cursor<&[u8]>> for NbtItem {
+    type Error = std::io::Error;
+
     /// 完整逻辑~
-    fn from(value: Reader) -> NbtItem { todo!() }
+    fn try_from(in_value: Reader) -> Result<NbtItem, Self::Error> {
+        let mut value: Reader = in_value.clone();
+        let mut items: Vec<NbtItem> = Vec::new();
+        loop {
+            // 读取类型
+            let mut buff = [0_u8; 1];
+            _ = value.read(&mut buff).unwrap();
+            let type_code: NbtStatus = match buff {
+                [0x00] => NbtStatus::End,
+                [0x01] => NbtStatus::Going(NbtItem::Value(NbtValue::from_bool(&mut value))),
+                [0x02] => NbtStatus::Going(NbtItem::Value(NbtValue::from_i16(&mut value))),
+                [0x03] => NbtStatus::Going(NbtItem::Value(NbtValue::from_i32(&mut value))),
+                [0x04] => NbtStatus::Going(NbtItem::Value(NbtValue::from_i64(&mut value))),
+                [0x05] => NbtStatus::Going(NbtItem::Value(NbtValue::from_f32(&mut value))),
+                [0x06] => NbtStatus::Going(NbtItem::Value(NbtValue::from_f64(&mut value))),
+                [0x07] => NbtStatus::Going(NbtItem::from(read::from_bool_array(&mut value))),
+                [0x08] => NbtStatus::Going(NbtItem::Value(NbtValue::from_string(&mut value))),
+                [0x09] => NbtStatus::Going(NbtItem::from(read::from_nbt_list(&mut value))),
+                [0x0A] => NbtStatus::Going(NbtItem::from(read::from_compound(&mut value))),
+                [0x0B] => NbtStatus::Going(NbtItem::from(read::from_i32_array(&mut value))),
+                [0x0C] => NbtStatus::Going(NbtItem::from(read::from_i64_array(&mut value))),
+                _ => NbtStatus::Error(std::io::Error::new(
+                    std::io::ErrorKind::InvalidData,
+                    format!(
+                        "WTF while reading Nbt Item \ntype: {:?}\nreader pos: {:?}",
+                        buff,
+                        value.position()
+                    ),
+                )),
+            };
+            match type_code {
+                NbtStatus::End => {
+                    break;
+                }
+                NbtStatus::Going(item) => {
+                    items.push(item);
+                }
+                NbtStatus::Error(e) => {
+                    return Err(e);
+                }
+            }
+        }
+        // 理论上 长度应该为 2
+        return if items.len() >= 3 {
+            Ok(NbtItem::Array(NbtList::from(items)))
+        } else {
+            Ok(items[0].clone())
+        };
+    }
 }