feat: implement menu bar + add file picker dep

.gitmodules

@@ -16,3 +16,6 @@
 [submodule "lib/zgui"]
 	path = lib/zgui
 	url = https://git.musuka.dev/paoda/zgui
+[submodule "lib/nfd-zig"]
+	path = lib/nfd-zig
+	url = https://github.com/fabioarnold/nfd-zig

build.zig

@@ -3,6 +3,7 @@ const builtin = @import("builtin");
 
 const Sdk = @import("lib/SDL.zig/Sdk.zig");
 const zgui = @import("lib/zgui/build.zig");
+const nfd = @import("lib/nfd-zig/build.zig");
 
 pub fn build(b: *std.build.Builder) void {
     // Minimum Zig Version
@@ -45,6 +46,10 @@ pub fn build(b: *std.build.Builder) void {
     // OpenGL 3.3 Bindings
     exe.addPackagePath("gl", "lib/gl.zig");
 
+    // NativeFileDialog(ue) Bindings
+    exe.linkLibrary(nfd.makeLib(b, mode, target));
+    exe.addPackage(nfd.getPackage("nfd"));
+
     // Zig SDL Bindings: https://github.com/MasterQ32/SDL.zig
     const sdk = Sdk.init(b);
     sdk.link(exe, .dynamic);
@@ -53,8 +58,8 @@ pub fn build(b: *std.build.Builder) void {
     // Dear ImGui bindings
     const zgui_options = zgui.BuildOptionsStep.init(b, .{ .backend = .sdl2_opengl3 });
     const zgui_pkg = zgui.getPkg(&.{zgui_options.getPkg()});
-    exe.addPackage(zgui_pkg);
     zgui.link(exe, zgui_options);
+    exe.addPackage(zgui_pkg);
 
     exe.setBuildMode(mode);
     exe.install();

lib/nfd-zig

@@ -0,0 +1 @@
+Subproject commit 75acefd571ede5361514b3a8ae9c8b36c6908d36

src/platform.zig

@@ -2,6 +2,7 @@ const std = @import("std");
 const SDL = @import("sdl2");
 const gl = @import("gl");
 const zgui = @import("zgui");
+const nfd = @import("nfd");
 
 const emu = @import("core/emu.zig");
 const config = @import("config.zig");
@@ -34,6 +35,7 @@ pub const Gui = struct {
 
     const State = struct {
         fps_hist: RingBuffer(u32),
+        should_quit: bool = false,
 
         pub fn init(allocator: Allocator) !@This() {
             const history = try allocator.alloc(u32, 0x400);
@@ -261,6 +263,36 @@ pub const Gui = struct {
     fn draw(self: *Self, tex_id: GLuint, cpu: *const Arm7tdmi) void {
         const win_scale = config.config().host.win_scale;
 
+        {
+            _ = zgui.beginMainMenuBar();
+            defer zgui.endMainMenuBar();
+
+            if (zgui.beginMenu("File", true)) {
+                defer zgui.endMenu();
+
+                if (zgui.menuItem("Quit", .{})) self.state.should_quit = true;
+                if (zgui.menuItem("Insert ROM", .{})) blk: {
+                    const maybe_path = nfd.openFileDialog("gba", null) catch |e| {
+                        log.err("failed to open file dialog: {?}", .{e});
+                        break :blk;
+                    };
+
+                    if (maybe_path) |file_path| {
+                        defer nfd.freePath(file_path);
+                        log.info("user chose: \"{s}\"", .{file_path});
+
+                        // emu.loadRom(cpu, file_path);
+                    }
+                }
+            }
+
+            if (zgui.beginMenu("Emulation", true)) {
+                defer zgui.endMenu();
+
+                if (zgui.menuItem("Restart", .{})) log.warn("TODO: Restart Emulator", .{});
+            }
+        }
+
         {
             const w = @intToFloat(f32, gba_width * win_scale);
             const h = @intToFloat(f32, gba_height * win_scale);
@@ -410,6 +442,9 @@ pub const Gui = struct {
         emu_loop: while (true) {
             var event: SDL.SDL_Event = undefined;
 
+            // Quit Signal from Dear Imgui
+            if (self.state.should_quit) break :emu_loop;
+
             while (SDL.SDL_PollEvent(&event) != 0) {
                 _ = zgui.backend.processEvent(&event);