From 181f29970e0cc592f5a0da3bd61fd5c7318c0318 Mon Sep 17 00:00:00 2001
From: David Allemang <david.allemang@kitware.com>
Date: Thu, 27 Jun 2024 09:26:53 -0400
Subject: [PATCH] WIP: event bus

---
 src/au.zig | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 84 insertions(+), 5 deletions(-)

diff --git a/src/au.zig b/src/au.zig
index 8b6f2ae..046ae15 100644
--- a/src/au.zig
+++ b/src/au.zig
@@ -80,9 +80,13 @@ pub fn init(alloc: std.mem.Allocator) !void {
 
     try init_device(alloc);
     errdefer deinit_device();
+
+    try init_event_bus(alloc);
+    errdefer deinit_event_bus();
 }
 
 pub fn deinit() void {
+    deinit_event_bus();
     deinit_device();
     deinit_window();
     deinit_instance();
@@ -383,9 +387,11 @@ const Window = struct {
 
     handle: *c.GLFWwindow,
     surface: vk.SurfaceKHR,
+    events: std.ArrayList(Event),
 
-    pub fn init(title: [*:0]const u8, extent: vk.Extent2D) !Self {
+    pub fn init(alloc: std.mem.Allocator, title: [*:0]const u8, extent: vk.Extent2D) !Self {
         var self: Self = undefined;
+        self.events = std.ArrayList(Event).init(alloc);
 
         c.glfwWindowHintString(c.GLFW_X11_CLASS_NAME, "floating_window");
         c.glfwWindowHintString(c.GLFW_X11_INSTANCE_NAME, "floating_window");
@@ -409,6 +415,7 @@ const Window = struct {
     }
 
     pub fn deinit(self: Self) void {
+        self.events.deinit();
         I.destroySurfaceKHR(self.surface, null);
         c.glfwDestroyWindow(self.handle);
     }
@@ -417,16 +424,88 @@ const Window = struct {
         return c.glfwWindowShouldClose(self.handle) == c.GLFW_TRUE;
     }
 
-    pub fn wait_events(_: Self) void {
+    pub fn wait_events(self: Self, events: std.ArrayList(Event)) void {
         c.glfwWaitEvents();
-        // todo events as values? push into a buffer and return here?
+        events.clearRetainingCapacity();
+        events.appendSlice(self.events.items);
+        self.events.clearRetainingCapacity();
     }
 
-    pub fn poll_events(_: Self) void {
+    pub fn poll_events(self: Self, events: *std.ArrayList(Event)) void {
         c.glfwPollEvents();
+        events.clearRetainingCapacity();
+        events.appendSlice(self.events.items);
+        self.events.clearRetainingCapacity();
     }
 
-    pub fn wait_events_timeout(seconds: f64) void {
+    pub fn wait_events_timeout(seconds: f64, events: *std.ArrayList(Event)) void {
         c.glfwWaitEventsTimeout(seconds);
     }
 };
+
+pub fn onCharMods(window: ?*c.GLFWwindow, code: u32, mods: i32) callconv(.C) void {
+    const w: *Window =
+        @ptrCast(c.glfwGetWindowUserPointer(window));
+    w.events.append(.{
+        .charMods = .{
+            .codepoint = @intCast(code),
+            .mods = mods,
+        },
+    });
+}
+
+pub fn onMouseButton(window: ?*c.GLFWwindow, btn: c_int, action: c_int, mods: c_int) callconv(.C) void {
+    const w: *Window =
+        @ptrCast(c.glfwGetWindowUserPointer(window));
+    w.events.append(.{
+        .mouseButton = .{
+            .btn = btn,
+            .action = action == c.GLFW_PRESS,
+            .mods = mods,
+        },
+    });
+}
+
+const Event = union(enum) {
+    charMods: struct {
+        codepoint: u21,
+        mods: i32,
+    },
+    mouseButton: struct {
+        btn: u32, // todo enum
+        action: bool, // todo enum
+        mods: u32,
+    },
+};
+
+// pub const GLFWwindowposfun = ?*const fn (?*GLFWwindow, c_int, c_int) callconv(.C) void;
+// pub const GLFWwindowsizefun = ?*const fn (?*GLFWwindow, c_int, c_int) callconv(.C) void;
+// pub const GLFWwindowclosefun = ?*const fn (?*GLFWwindow) callconv(.C) void;
+// pub const GLFWwindowrefreshfun = ?*const fn (?*GLFWwindow) callconv(.C) void;
+// pub const GLFWwindowfocusfun = ?*const fn (?*GLFWwindow, c_int) callconv(.C) void;
+// pub const GLFWwindowiconifyfun = ?*const fn (?*GLFWwindow, c_int) callconv(.C) void;
+// pub const GLFWwindowmaximizefun = ?*const fn (?*GLFWwindow, c_int) callconv(.C) void;
+// pub const GLFWframebuffersizefun = ?*const fn (?*GLFWwindow, c_int, c_int) callconv(.C) void;
+// pub const GLFWwindowcontentscalefun = ?*const fn (?*GLFWwindow, f32, f32) callconv(.C) void;
+// pub const GLFWmousebuttonfun = ?*const fn (?*GLFWwindow, c_int, c_int, c_int) callconv(.C) void;
+// pub const GLFWcursorposfun = ?*const fn (?*GLFWwindow, f64, f64) callconv(.C) void;
+// pub const GLFWcursorenterfun = ?*const fn (?*GLFWwindow, c_int) callconv(.C) void;
+// pub const GLFWscrollfun = ?*const fn (?*GLFWwindow, f64, f64) callconv(.C) void;
+// pub const GLFWkeyfun = ?*const fn (?*GLFWwindow, c_int, c_int, c_int, c_int) callconv(.C) void;
+// pub const GLFWcharfun = ?*const fn (?*GLFWwindow, c_uint) callconv(.C) void;
+// pub const GLFWcharmodsfun = ?*const fn (?*GLFWwindow, c_uint, c_int) callconv(.C) void;
+// pub const GLFWdropfun = ?*const fn (?*GLFWwindow, c_int, [*c][*c]const u8) callconv(.C) void;
+// pub const GLFWmonitorfun = ?*const fn (?*GLFWmonitor, c_int) callconv(.C) void;
+// pub const GLFWjoystickfun = ?*const fn (c_int, c_int) callconv(.C) void;
+
+fn init_event_bus() !void {
+    c.glfwSetWindowUserPointer(W.handle, W);
+    _ = c.glfwSetCharModsCallback(W.handle, onCharMods);
+    _ = c.glfwSetMouseButtonCallback(W.handle, onMouseButton);
+}
+
+fn deinit_event_bus() void {
+    _ = c.glfwSetCharModsCallback(W.handle, null);
+    _ = c.glfwSetMouseButtonCallback(W.handle, null);
+    c.glfwSetWindowUserPointer(W.handle, null);
+}