From ba4945f598a095cf43f587eb98910db0ac09fa9d Mon Sep 17 00:00:00 2001
From: asur4s <todaymofish@gmail.com>
Date: Sat, 18 Mar 2023 20:57:19 -0700
Subject: [PATCH] Get char when hot key is pressed

---
 src/keyboard.rs         | 18 ++++++++++---
 src/platform/windows.rs | 58 +++++++++++++++++++++++++++++++++++++++--
 2 files changed, 71 insertions(+), 5 deletions(-)

diff --git a/src/keyboard.rs b/src/keyboard.rs
index bfff9ff86..f613a06ef 100644
--- a/src/keyboard.rs
+++ b/src/keyboard.rs
@@ -3,11 +3,13 @@ use crate::client::get_key_state;
 use crate::common::GrabState;
 #[cfg(feature = "flutter")]
 use crate::flutter::{CUR_SESSION_ID, SESSIONS};
+#[cfg(target_os = "windows")]
+use crate::platform::windows::get_char_by_vk;
 #[cfg(not(any(feature = "flutter", feature = "cli")))]
 use crate::ui::CUR_SESSION;
-use hbb_common::message_proto::*;
 #[cfg(not(any(target_os = "android", target_os = "ios")))]
 use hbb_common::log;
+use hbb_common::message_proto::*;
 use rdev::{Event, EventType, Key};
 #[cfg(any(target_os = "windows", target_os = "macos"))]
 use std::sync::atomic::{AtomicBool, Ordering};
@@ -789,8 +791,18 @@ fn try_fill_unicode(event: &Event, key_event: &KeyEvent, events: &mut Vec<KeyEve
                 }
             }
         }
-        None => {}
+        None => {
+            #[cfg(target_os = "windows")]
+            if is_hot_key_modifiers_down() && unsafe { !IS_0X021D_DOWN }{
+                if let Some(chr) = get_char_by_vk(event.code as u32) {
+                    let mut evt = key_event.clone();
+                    evt.set_seq(chr.to_string());
+                    events.push(evt);
+                }
+            }
+        }
     }
+    
 }
 
 #[cfg(target_os = "windows")]
@@ -857,7 +869,7 @@ pub fn translate_keyboard_mode(peer: &str, event: &Event, key_event: KeyEvent) -
     }
 
     #[cfg(target_os = "windows")]
-    if unsafe { IS_0X021D_DOWN } || !is_hot_key_modifiers_down() {
+    if matches!(event.event_type, EventType::KeyPress(_)) {
         try_fill_unicode(event, &key_event, &mut events);
     }
 
diff --git a/src/platform/windows.rs b/src/platform/windows.rs
index 696a18ab9..ac3dc4e1d 100644
--- a/src/platform/windows.rs
+++ b/src/platform/windows.rs
@@ -10,6 +10,7 @@ use hbb_common::{
     sleep, timeout, tokio,
 };
 use std::io::prelude::*;
+use std::ptr::null_mut;
 use std::{
     ffi::OsString,
     fs, io, mem,
@@ -26,8 +27,8 @@ use winapi::{
         handleapi::CloseHandle,
         minwinbase::STILL_ACTIVE,
         processthreadsapi::{
-            GetCurrentProcess, GetCurrentProcessId, GetExitCodeProcess, OpenProcess,
-            OpenProcessToken, PROCESS_INFORMATION, STARTUPINFOW,
+            GetCurrentProcess, GetCurrentProcessId, GetCurrentThreadId, GetExitCodeProcess,
+            OpenProcess, OpenProcessToken, PROCESS_INFORMATION, STARTUPINFOW,
         },
         securitybaseapi::GetTokenInformation,
         shellapi::ShellExecuteW,
@@ -2072,6 +2073,51 @@ mod cert {
     }
 }
 
+pub fn get_char_by_vk(vk: u32) -> Option<char> {
+    let mut buff = [0_u16; BUF_LEN as usize];
+    let buff_ptr = buff.as_mut_ptr();
+    const BUF_LEN: i32 = 32;
+    let len = unsafe {
+        let current_window_thread_id = GetWindowThreadProcessId(GetForegroundWindow(), null_mut());
+        let layout = GetKeyboardLayout(current_window_thread_id);
+
+        // refs: https://github.com/fufesou/rdev/blob/25a99ce71ab42843ad253dd51e6a35e83e87a8a4/src/windows/keyboard.rs#L115
+        let press_state = 129;
+        let mut state: [BYTE; 256] = [0; 256];
+        let shift_left = rdev::get_modifier(rdev::Key::ShiftLeft);
+        let shift_right = rdev::get_modifier(rdev::Key::ShiftRight);
+        if shift_left {
+            state[VK_LSHIFT as usize] = press_state;
+        }
+        if shift_right {
+            state[VK_RSHIFT as usize] = press_state;
+        }
+        if shift_left || shift_right {
+            state[VK_SHIFT as usize] = press_state;
+        }
+        buff = [0; 32];
+        let buff_ptr = buff.as_mut_ptr();
+        ToUnicodeEx(vk, 0x00, &state as _, buff_ptr, BUF_LEN, 0, layout)
+    };
+    if len == 1 {
+        if let Some(chr) = String::from_utf16(&buff[..len as usize])
+            .ok()?
+            .chars()
+            .next()
+        {
+            if chr.is_control() {
+                return None;
+            } else {
+                Some(chr)
+            }
+        } else {
+            None
+        }
+    } else {
+        None
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -2084,4 +2130,12 @@ mod tests {
     fn test_uninstall_cert() {
         println!("uninstall driver certs: {:?}", cert::uninstall_certs());
     }
+
+    #[test]
+    fn test_get_char_by_vk() {
+        let chr = get_char_by_vk(0x41); // VK_A
+        assert_eq!(chr, Some('a'));
+        let chr = get_char_by_vk(VK_ESCAPE as u32); // VK_ESC
+        assert_eq!(chr, None)
+    }
 }