From e91bf807ec4680f78f9c8c2e6471399d164b15fa Mon Sep 17 00:00:00 2001
From: Mattias Eriksson <snaggen@mayam.com>
Date: Wed, 31 Jan 2024 15:43:20 +0100
Subject: [PATCH] Improve SGR Scroll Wheel support

---
 src/mouse_reporter.rs | 47 ++++++++++++++++++++++++++++++++++++++++---
 src/terminal.rs       | 34 ++++++++++++++++++++++++-------
 src/terminal_box.rs   |  9 +++++++--
 3 files changed, 78 insertions(+), 12 deletions(-)

diff --git a/src/mouse_reporter.rs b/src/mouse_reporter.rs
index 77c2a6d..d9a339a 100644
--- a/src/mouse_reporter.rs
+++ b/src/mouse_reporter.rs
@@ -172,9 +172,50 @@ impl MouseReporter {
         }
     }
 
+    pub fn report_sgr_mouse_wheel_scroll(
+        &self,
+        terminal: &Terminal,
+        term_cell_width: f32,
+        term_cell_height: f32,
+        delta: ScrollDelta,
+        modifiers: &Modifiers,
+        x: u32,
+        y: u32,
+    ) {
+        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),
+        };
+        let (mut button_no, amount) = if delta_y > 0.0 {
+            (64, delta_y.abs()) //Wheel UP
+        } else if delta_y < 0.0 {
+            (65, delta_y.abs()) //Wheel Down
+        } else if delta_x < 0.0 {
+            (66, delta_x.abs()) //Wheel Left
+        } else if delta_x > 0.0 {
+            (67, delta_x.abs()) //Wheel Right
+        } else {
+            return;
+        };
+
+        if modifiers.shift() {
+            button_no += 4;
+        }
+        if modifiers.alt() {
+            button_no += 8;
+        }
+        if modifiers.control() {
+            button_no += 16;
+        }
+        let term_code = format!("\x1b[<{};{};{}M", button_no, x + 1, y + 1);
+        for _ in 0..amount as u32 {
+            terminal.input_no_scroll(term_code.as_bytes().to_vec());
+        }
+    }
+
     //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(
+    pub fn report_mouse_wheel_as_arrows(
         &self,
         terminal: &Terminal,
         term_cell_width: f32,
@@ -188,9 +229,9 @@ impl MouseReporter {
         //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())
+                terminal.input_no_scroll(b"\x1B[A".as_slice())
             } else if delta_y < 0.0 {
-                terminal.input_no_scroll(b"\x1B[1;3B".as_slice())
+                terminal.input_no_scroll(b"\x1B[B".as_slice())
             }
         }
     }
diff --git a/src/terminal.rs b/src/terminal.rs
index 322abfa..25f6f99 100644
--- a/src/terminal.rs
+++ b/src/terminal.rs
@@ -805,13 +805,33 @@ impl Terminal {
             }
         }
     }
-    pub fn scroll_mouse(&mut self, delta: ScrollDelta) {
-        self.mouse_reporter.report_mouse_wheel_scroll(
-            self,
-            self.size().cell_width,
-            self.size().cell_height,
-            delta,
-        );
+    pub fn scroll_mouse(
+        &mut self,
+        delta: ScrollDelta,
+        modifiers: &cosmic::iced::keyboard::Modifiers,
+        x: u32,
+        y: u32,
+    ) {
+        let term_lock = self.term.lock();
+        let mode = term_lock.mode();
+        if mode.contains(TermMode::SGR_MOUSE) {
+            self.mouse_reporter.report_sgr_mouse_wheel_scroll(
+                self,
+                self.size().cell_width,
+                self.size().cell_height,
+                delta,
+                modifiers,
+                x,
+                y,
+            );
+        } else {
+            self.mouse_reporter.report_mouse_wheel_as_arrows(
+                self,
+                self.size().cell_width,
+                self.size().cell_height,
+                delta,
+            );
+        }
     }
 }
 
diff --git a/src/terminal_box.rs b/src/terminal_box.rs
index d55874d..181d162 100644
--- a/src/terminal_box.rs
+++ b/src/terminal_box.rs
@@ -1191,9 +1191,14 @@ where
                 }
             }
             Event::Mouse(MouseEvent::WheelScrolled { delta }) => {
-                if let Some(_p) = cursor_position.position_in(layout.bounds()) {
+                if let Some(p) = cursor_position.position_in(layout.bounds()) {
                     if is_mouse_mode {
-                        terminal.scroll_mouse(delta);
+                        let x = (p.x - layout.bounds().x) - self.padding.left;
+                        let y = (p.y - layout.bounds().y) - self.padding.top;
+                        //TODO: better calculation of position
+                        let col = x / terminal.size().cell_width;
+                        let row = y / terminal.size().cell_height;
+                        terminal.scroll_mouse(delta, &state.modifiers, col as u32, row as u32);
                     } else {
                         match delta {
                             ScrollDelta::Lines { x: _, y } => {