1 files changed, 150 insertions, 0 deletions
diff --git a/src/line/buf.rs b/src/line/buf.rs
new file mode 100644
index 0000000..420546a
--- /dev/null
+++ b/src/line/buf.rs
@@ -0,0 +1,150 @@
+use crate::cursor::*;
+use std::io::Write;
+
+pub struct LineBuf {
+    pre: Vec<u8>,
+    post: Vec<u8>,
+    dirty: bool,
+}
+
+impl Default for LineBuf {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[allow(unused)]
+impl LineBuf {
+    pub fn new() -> Self {
+        Self {
+            pre: Vec::new(),
+            post: Vec::new(),
+            dirty: false,
+        }
+    }
+
+    pub fn del_left(&mut self) -> Option<u8> {
+        self.dirty = true;
+        self.pre.pop()
+    }
+
+    pub fn del_right(&mut self) -> Option<u8> {
+        self.dirty = true;
+        self.post.pop()
+    }
+
+    pub fn len(&self) -> usize {
+        self.pre.len() + self.post.len()
+    }
+
+    pub fn left(&mut self) -> bool {
+        if let Some(byte) = self.del_left() {
+            self.post.push(byte);
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn right(&mut self) -> bool {
+        if let Some(byte) = self.del_right() {
+            self.pre.push(byte);
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn all_left(&mut self) -> usize {
+        let n = self.pre.len();
+        while self.left() {}
+        n
+    }
+
+    pub fn all_right(&mut self) -> usize {
+        let n = self.post.len();
+        while self.right() {}
+        n
+    }
+
+    pub fn get_left(&self) -> Option<u8> {
+        self.pre.last().cloned()
+    }
+
+    pub fn get_right(&self) -> Option<u8> {
+        self.post.last().cloned()
+    }
+
+    pub fn add(&mut self, chr: u8) {
+        self.dirty = true;
+        self.pre.push(chr);
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.pre.is_empty() && self.post.is_empty()
+    }
+
+    pub fn is_dirty(&self) -> bool {
+        self.dirty
+    }
+
+    /// sets content all to the left
+    pub fn set_content(&mut self, buf: Vec<u8>) {
+        self.pre = buf;
+        self.post = Vec::new();
+    }
+
+    pub fn pre(&self) -> &[u8] {
+        &self.pre
+    }
+
+    pub fn into_bytes(&self) -> Vec<u8> {
+        let mut buf = Vec::with_capacity(self.pre.len() + self.post.len());
+        buf.extend_from_slice(&self.pre);
+        for b in self.post.iter().rev() {
+            buf.push(*b);
+        }
+        buf
+    }
+
+    pub fn distance_from_right_end(&self) -> usize {
+        self.post.len()
+    }
+
+    /// returns the whole contents of the buffer, and empties it in the process
+    pub fn dump(&mut self) -> Vec<u8> {
+        while self.right() {}
+        let mut buf = Vec::new();
+        core::mem::swap(&mut self.pre, &mut buf);
+        self.dirty = false;
+        buf
+    }
+
+    pub fn clear(&mut self) {
+        self.pre.clear();
+        self.post.clear();
+        self.dirty = false;
+    }
+
+    pub fn display_pre(&self) {
+        std::io::stdout().write_all(&self.pre).unwrap();
+    }
+
+    /// TODO: kinda ugly that this is here
+    pub fn display_post(&self, post: &[u8]) {
+        for &x in self.post.iter().rev() {
+            std::io::stdout().write_all(&[x]).unwrap();
+        }
+        std::io::stdout().write_all(post).unwrap();
+        move_cursor(Direction::Left, self.post.len() + post.len());
+        std::io::stdout().flush().unwrap();
+    }
+
+    pub fn left_len(&self) -> usize {
+        self.pre.len()
+    }
+
+    pub fn right_len(&self) -> usize {
+        self.post.len()
+    }
+}