1 files changed, 67 insertions, 0 deletions
diff --git a/src/async.rs b/src/async.rs
new file mode 100644
index 0000000..a384da8
--- /dev/null
+++ b/src/async.rs
@@ -0,0 +1,67 @@
+use futures_lite::io::AsyncWriteExt as _;
+
+use super::private::TextmodeImpl as _;
+
+pub struct Textmode {
+    cur: vt100::Parser,
+    next: vt100::Parser,
+}
+
+impl super::private::TextmodeImpl for Textmode {
+    fn cur(&self) -> &vt100::Parser {
+        &self.cur
+    }
+
+    fn cur_mut(&mut self) -> &mut vt100::Parser {
+        &mut self.cur
+    }
+
+    fn next(&self) -> &vt100::Parser {
+        &self.next
+    }
+
+    fn next_mut(&mut self) -> &mut vt100::Parser {
+        &mut self.next
+    }
+}
+
+impl super::Textmode for Textmode {}
+
+impl Textmode {
+    pub async fn new() -> std::io::Result<Self> {
+        let (rows, cols) = match terminal_size::terminal_size() {
+            Some((terminal_size::Width(w), terminal_size::Height(h))) => {
+                (h, w)
+            }
+            _ => (24, 80),
+        };
+        let cur = vt100::Parser::new(rows, cols, 0);
+        let next = vt100::Parser::new(rows, cols, 0);
+
+        let self_ = Self { cur, next };
+        self_
+            .write_stdout(b"\x1b7\x1b[?47h\x1b[2J\x1b[H\x1b[?25h")
+            .await?;
+        Ok(self_)
+    }
+
+    // TODO: without async drop or async closures, i'm not sure how to do
+    // better than this
+    pub async fn cleanup(&mut self) -> std::io::Result<()> {
+        self.write_stdout(b"\x1b[?47l\x1b8\x1b[?25h").await
+    }
+
+    pub async fn refresh(&mut self) -> std::io::Result<()> {
+        let diff = self.next().screen().contents_diff(self.cur().screen());
+        self.write_stdout(&diff).await?;
+        self.cur_mut().process(&diff);
+        Ok(())
+    }
+
+    async fn write_stdout(&self, buf: &[u8]) -> std::io::Result<()> {
+        let mut stdout = blocking::Unblock::new(std::io::stdout());
+        stdout.write_all(buf).await?;
+        stdout.flush().await?;
+        Ok(())
+    }
+}