From 071cf7741f9b23628c27d2449a601182fc63dcec Mon Sep 17 00:00:00 2001
From: catvayor <catvayor@katvayor.net>
Date: Mon, 14 Oct 2024 17:44:22 +0200
Subject: [PATCH] feat(agb02/gpio): auto-repeat on joystick

---
 machines/agb02/agb/agb.cpp | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/machines/agb02/agb/agb.cpp b/machines/agb02/agb/agb.cpp
index 343be6a..05692b9 100644
--- a/machines/agb02/agb/agb.cpp
+++ b/machines/agb02/agb/agb.cpp
@@ -10,10 +10,11 @@ using namespace std::literals::chrono_literals;
 
 constexpr std::chrono::microseconds debounce = 40ms;
 constexpr std::chrono::microseconds poll_period = 5ms;
+constexpr std::chrono::microseconds autorepeat_delay = 70ms;
 constexpr std::chrono::microseconds server_ratelimit = 50ms;
 constexpr std::chrono::microseconds retry_timeout = 500ms;
 
-constexpr std::pair<double, double> joystick_movement(.3, .3);
+constexpr double joystick_movement = 0.2;
 
 const gpiod::line::offsets drive_down = { 21, 13, 6 };
 
@@ -94,8 +95,26 @@ int main(const int argc, char const* const* const argv) {
 
   /// internal state and buffers ///
 
+  std::chrono::time_point now = std::chrono::system_clock::now();
+
   gpiod::line::values joystick_read(4);
+  gpiod::line::values joystick_last_read(4);
+  line_reader.get_values(joystick, joystick_read);
+  std::vector<std::chrono::time_point<std::chrono::system_clock>> rising_point = { now, now, now, now };
   std::pair<double, double> spot_pos(0.0, 0.0); //TODO: init from server
+  auto joystick_move = [&](int i) -> double {
+    if (! bool(joystick_read[i]))
+      return 0.0;
+    else if (bool(joystick_last_read[i])){
+      if (now - rising_point[i] < autorepeat_delay)
+        return 0.0;
+      else
+        return joystick_movement;
+    } else {
+      rising_point[i] = now;
+      return 1.0;
+    }
+  };
 
   uint8_t decoder_pos = 0; //TODO: init from server
   uint8_t decoder_realpos = read_decoder_realpos(line_reader);
@@ -104,19 +123,21 @@ int main(const int argc, char const* const* const argv) {
   bool black_pressed = false;
 
   bool has_changed = true;
-  std::chrono::time_point last_send = std::chrono::system_clock::now();
+  std::chrono::time_point last_send = now;
   std::string postData;
 
   for(;;){
     std::this_thread::sleep_for(poll_period);
+    now = std::chrono::system_clock::now();
 
     /// joystick ///
+    std::swap(joystick_read, joystick_last_read);
     line_reader.get_values(joystick, joystick_read);
 
-    if(bool(joystick_read[0])) spot_pos.first  += joystick_movement.first;
-    if(bool(joystick_read[1])) spot_pos.second += joystick_movement.second;
-    if(bool(joystick_read[2])) spot_pos.first  -= joystick_movement.first;
-    if(bool(joystick_read[3])) spot_pos.second -= joystick_movement.second;
+    spot_pos.first  += joystick_move(0);
+    spot_pos.second += joystick_move(1);
+    spot_pos.first  -= joystick_move(2);
+    spot_pos.second -= joystick_move(3);
 
     if (bool(joystick_read[0]) || bool(joystick_read[1])
         || bool(joystick_read[2]) || bool(joystick_read[3])){
@@ -157,7 +178,6 @@ int main(const int argc, char const* const* const argv) {
       has_changed = true;
 
     /// server notification
-    std::chrono::time_point now = std::chrono::system_clock::now();
     if(has_changed && (now - last_send > server_ratelimit)){
       postData.clear();
       std::format_to(std::back_inserter(postData), "{{"