Add support for Mouse Events

src/mouse_reporter.rs

@@ -0,0 +1,197 @@
+use cosmic::{
+    iced::mouse::{Event as MouseEvent, ScrollDelta},
+    iced::{keyboard::Modifiers, mouse::Button, Event},
+};
+
+use crate::terminal::Terminal;
+
+const SCROLL_SPEED: u32 = 3;
+
+#[derive(Default)]
+pub struct MouseReporter {
+    last_movment_x: Option<u32>,
+    last_movment_y: Option<u32>,
+    button: Option<Button>,
+}
+
+impl MouseReporter {
+    fn button_number(&self, button: Button) -> Option<u8> {
+        match button {
+            Button::Left => Some(0),
+            Button::Middle => Some(1),
+            Button::Right => Some(2),
+            _ => None,
+        }
+    }
+
+    //Implemented according to
+    //https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h2-Mouse-Tracking
+    pub fn normal_mouse_code(
+        &mut self,
+        event: Event,
+        modifiers: &Modifiers,
+        is_utf8: bool,
+        x: u32,
+        y: u32,
+    ) -> Option<Vec<u8>> {
+        //Buttons are handle slightly different between normal and sgr
+        //for normal/utf8 the button release is always reported as button 3
+        let Some(mut button) = (match event {
+            Event::Mouse(MouseEvent::ButtonPressed(b)) => {
+                self.button = Some(b);
+                self.button_number(b)
+            }
+            Event::Mouse(MouseEvent::ButtonReleased(_b)) => {
+                self.button = None;
+                Some(3)
+            }
+            Event::Mouse(MouseEvent::CursorMoved { .. }) => {
+                //Button pressed is reported as button 32 + 0,1,2 and event code M
+                //And only reported if a button is previously pressed
+                if (self.last_movment_x, self.last_movment_y) == (Some(x), Some(y)) {
+                    return None;
+                } else {
+                    self.last_movment_x = Some(x);
+                    self.last_movment_y = Some(y);
+                }
+                //It seems that we should add 32 to signal movement even for normal mode
+                //On button-motion events, xterm adds 32 to the event code (the third
+                //character, Cb).
+                //For example, motion into cell x,y with button 1 down is reported as
+                //CSI M @ CxCy ( @  = 32 + 0 (button 1) + 32 (motion indicator) ).
+                self.button
+                    .and_then(|button| self.button_number(button))
+                    .map(|b| b + 32)
+            }
+            _ => None,
+        }) else {
+            return None;
+        };
+
+        if modifiers.shift() {
+            button += 4;
+        }
+        if modifiers.alt() {
+            button += 8;
+        }
+        if modifiers.control() {
+            button += 16;
+        }
+
+        //Normal mode have a max of 223 (255 - 32), while utf8 extend this to 2015
+        let max_point: usize = if is_utf8 { 2015 } else { 223 };
+        if x as usize >= max_point || y as usize >= max_point {
+            return None;
+        }
+
+        let utf8_encode_and_append = |mut pos: u32, dest: &mut Vec<u8>| {
+            pos += 1 + 32;
+            let mut utf8 = [0; 2]; //This is large enough since we have a max of 2015
+            dest.extend_from_slice(
+                (char::from_u32(pos).unwrap()) //This unwrap and encode_utf8 is safe due to our
+                    //specific range, pos will max be 2047
+                    .encode_utf8(&mut utf8)
+                    .as_bytes(),
+            );
+        };
+
+        //SPEC: Likewise, Cb will be UTF-8 encoded, to reduce confusion with wheel mouse events.
+        //Always, or only when the the cooardinates is used? No other terminal seems to do this a
+        //all? Doing what they are doing for now.
+        let mut buf: Vec<u8> = vec![b'\x1b', b'[', b'M', 32 + button];
+        //Should we remove 32+button from previous line, and use this instead? Or only on >= 95
+        //utf8_encode_and_append(32 + button, &mut buf);
+
+        //For utf8 spec say: For positions less than 95, the resulting output is identical under both modes.
+        //But also: Under normal mouse mode, positions outside (160,94) result in byte pairs which can be interpreted as a single UTF-8
+        if is_utf8 && x >= 95 {
+            utf8_encode_and_append(x, &mut buf);
+        } else {
+            //SPEC: For positions less than 95, the resulting output is identical under both modes.
+            buf.push(32 + 1 + x as u8);
+        }
+
+        if is_utf8 && y >= 95 {
+            utf8_encode_and_append(y, &mut buf);
+        } else {
+            //SPEC For positions less than 95, the resulting output is identical under both modes.
+            buf.push(32 + 1 + y as u8);
+        }
+        Some(buf)
+    }
+
+    pub fn sgr_mouse_code(
+        &mut self,
+        event: Event,
+        modifiers: &Modifiers,
+        x: u32,
+        y: u32,
+    ) -> Option<Vec<u8>> {
+        let Some((button_no, event_code)) = (match event {
+            Event::Mouse(MouseEvent::ButtonPressed(button)) => {
+                //Button pressed is reported as button 0,1,2 and event code M
+                self.button = Some(button);
+                Some((self.button_number(button), "M"))
+            }
+            Event::Mouse(MouseEvent::ButtonReleased(button)) => {
+                //Button pressed is reported as button 0,1,2 and event code m
+                self.button = None;
+                Some((self.button_number(button), "m"))
+            }
+            Event::Mouse(MouseEvent::CursorMoved { .. }) => {
+                //Button pressed is reported as button 32 + 0,1,2 and event code M
+                //And only reported if a button is previously pressed
+                if (self.last_movment_x, self.last_movment_y) == (Some(x), Some(y)) {
+                    return None;
+                } else {
+                    self.last_movment_x = Some(x);
+                    self.last_movment_y = Some(y);
+                }
+                self.button
+                    .map(|button| (self.button_number(button).map(|b| b + 32), "M"))
+            }
+            _ => None,
+        }) else {
+            return None;
+        };
+
+        if let Some(mut button_no) = button_no {
+            if modifiers.shift() {
+                button_no += 4;
+            }
+            if modifiers.alt() {
+                button_no += 8;
+            }
+            if modifiers.control() {
+                button_no += 16;
+            }
+            let term_code = format!("\x1b[<{};{};{}{}", button_no, x + 1, y + 1, event_code);
+            Some(term_code.as_bytes().to_vec())
+        } else {
+            None
+        }
+    }
+
+    //Emulate mouse wheel scroll with up/down arrows. Using mouse spec uses
+    //scroll-back and scroll-forw actions, which moves whole windows like page up/page down.
+    pub fn report_mouse_wheel_scroll(
+        &self,
+        terminal: &Terminal,
+        term_cell_width: f32,
+        term_cell_height: f32,
+        delta: ScrollDelta,
+    ) {
+        let (_delta_x, delta_y) = match delta {
+            ScrollDelta::Lines { x, y } => (x, y),
+            ScrollDelta::Pixels { x, y } => (x / term_cell_width, y / term_cell_height),
+        };
+        //Send delta_y * SCROLL_SPEED number of Up/Down arrows
+        for _ in 0..(delta_y.abs() as u32 * SCROLL_SPEED) {
+            if delta_y > 0.0 {
+                terminal.input_no_scroll(b"\x1B[1;3A".as_slice())
+            } else if delta_y < 0.0 {
+                terminal.input_no_scroll(b"\x1B[1;3B".as_slice())
+            }
+        }
+    }
+}