1 files changed, 138 insertions, 5 deletions
diff --git a/src/lib.rs b/src/lib.rs
index 31e1bb2..39c201b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,7 +1,140 @@
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn it_works() {
-        assert_eq!(2 + 2, 4);
+use std::io::Write as _;
+
+pub mod color;
+
+pub struct Textmode {
+    cur: vt100::Parser,
+    next: vt100::Parser,
+}
+
+impl Textmode {
+    pub 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")?;
+        Ok(self_)
+    }
+
+    pub fn cursor_position(&self) -> (u16, u16) {
+        self.next.screen().cursor_position()
+    }
+
+    pub fn write(&mut self, buf: &[u8]) {
+        self.next.process(buf);
+    }
+
+    pub fn refresh(&mut self) -> std::io::Result<()> {
+        let diff = self.next.screen().contents_diff(self.cur.screen());
+        self.write_stdout(&diff)?;
+        self.cur.process(&diff);
+        Ok(())
+    }
+
+    pub fn set_size(&mut self, rows: u16, cols: u16) {
+        self.cur.set_size(rows, cols);
+        self.next.set_size(rows, cols);
+    }
+
+    pub fn write_str(&mut self, text: &str) {
+        self.write(text.as_bytes());
+    }
+
+    pub fn move_to(&mut self, row: u16, col: u16) {
+        self.write(b"\x1b[");
+        self.write_u16(row);
+        self.write(b";");
+        self.write_u16(col);
+        self.write(b"H");
+    }
+
+    pub fn clear(&mut self) {
+        self.write(b"\x1b[2J");
+    }
+
+    pub fn set_fgcolor(&mut self, color: vt100::Color) {
+        match color {
+            vt100::Color::Default => {
+                self.write(b"\x1b[39m");
+            }
+            vt100::Color::Idx(i) => {
+                if i < 8 {
+                    self.write(b"\x1b[");
+                    self.write_u8(30 + i);
+                    self.write(b"m");
+                } else {
+                    self.write(b"\x1b[38;5;");
+                    self.write_u8(i);
+                    self.write(b"m");
+                }
+            }
+            vt100::Color::Rgb(r, g, b) => {
+                self.write(b"\x1b[38;2;");
+                self.write_u8(r);
+                self.write(b";");
+                self.write_u8(g);
+                self.write(b";");
+                self.write_u8(b);
+                self.write(b"m");
+            }
+        }
+    }
+
+    pub fn set_bgcolor(&mut self, color: vt100::Color) {
+        match color {
+            vt100::Color::Default => {
+                self.write(b"\x1b[49m");
+            }
+            vt100::Color::Idx(i) => {
+                if i < 8 {
+                    self.write(b"\x1b[");
+                    self.write_u8(40 + i);
+                    self.write(b"m");
+                } else {
+                    self.write(b"\x1b[48;5;");
+                    self.write_u8(i);
+                    self.write(b"m");
+                }
+            }
+            vt100::Color::Rgb(r, g, b) => {
+                self.write(b"\x1b[48;2;");
+                self.write_u8(r);
+                self.write(b";");
+                self.write_u8(g);
+                self.write(b";");
+                self.write_u8(b);
+                self.write(b"m");
+            }
+        }
+    }
+
+    fn write_u16(&mut self, i: u16) {
+        // unwrap is fine because vt100::Parser::write can never fail
+        itoa::write(&mut self.next, i).unwrap();
+    }
+
+    fn write_u8(&mut self, i: u8) {
+        // unwrap is fine because vt100::Parser::write can never fail
+        itoa::write(&mut self.next, i).unwrap();
+    }
+
+    fn write_stdout(&self, buf: &[u8]) -> std::io::Result<()> {
+        let mut stdout = std::io::stdout();
+        stdout.write_all(buf)?;
+        stdout.flush()?;
+        Ok(())
+    }
+}
+
+impl Drop for Textmode {
+    fn drop(&mut self) {
+        let _ = self.write_stdout(b"\x1b[?47l\x1b8\x1b[?25h");
     }
 }