crown-engine/src/device/main_android.cpp

/*
 * Copyright (c) 2012-2025 Daniele Bartolini et al.
 * SPDX-License-Identifier: MIT
 */

#include "config.h"

#if CROWN_PLATFORM_ANDROID
#include "core/error/error.inl"
#include "core/guid.h"
#include "core/memory/globals.h"
#include "core/memory/memory.inl"
#include "core/thread/spsc_queue.inl"
#include "core/thread/thread.h"
#include "device/device.h"
#include "device/device_event_queue.inl"
#include <android/sensor.h>
#include <android/window.h>
#include <jni.h>
#include <stdlib.h>
#define STB_SPRINTF_IMPLEMENTATION
#define STB_SPRINTF_NOUNALIGNED
#include <stb_sprintf.h>

extern "C"
{
#include <android_native_app_glue.c>
}

namespace crown
{
static bool push_event(const OsEvent &ev);

struct AndroidDevice
{
	SPSCQueue<OsEvent, CROWN_MAX_OS_EVENTS> _events;
	DeviceEventQueue _queue;
	Thread _main_thread;
	DeviceOptions *_opts;
	ANativeWindow *_window;

	explicit AndroidDevice(Allocator &a)
		: _events(a)
		, _queue(push_event)
		, _opts(NULL)
	{
	}

	void run(struct android_app *app, DeviceOptions &opts)
	{
		_opts = &opts;

		app->userData = this;
		app->onAppCmd = crown::AndroidDevice::on_app_cmd;
		app->onInputEvent = crown::AndroidDevice::on_input_event;
		ANativeActivity_setWindowFlags(app->activity
			, AWINDOW_FLAG_FULLSCREEN | AWINDOW_FLAG_KEEP_SCREEN_ON
			, 0
			);

		while (app->destroyRequested == 0) {
			s32 num;
			android_poll_source *source;
			ALooper_pollOnce(-1, NULL, &num, (void **)&source);

			if (source != NULL)
				source->process(app, source);
		}

		_main_thread.stop();
	}

	void process_command(struct android_app *app, s32 cmd)
	{
		switch (cmd) {
		case APP_CMD_SAVE_STATE:
			break;

		case APP_CMD_INIT_WINDOW: {
			CE_ASSERT(app->window != NULL, "Android window is NULL");
			_window = app->window;

			// Push metrics here since Android does not trigger APP_CMD_WINDOW_RESIZED
			const s32 width  = ANativeWindow_getWidth(app->window);
			const s32 height = ANativeWindow_getHeight(app->window);
			_queue.push_resolution_event(width, height);

			if (!_main_thread.is_running()) {
				_main_thread.start([](void *user_data) {
						return crown::main_runtime(*((DeviceOptions *)user_data));
					}
					, _opts
					);
			}
			break;
		}

		case APP_CMD_TERM_WINDOW:
			// The window is being hidden or closed, clean it up.
			break;

		case APP_CMD_WINDOW_RESIZED:
			// Not triggered by Android
			break;

		case APP_CMD_GAINED_FOCUS:
			break;

		case APP_CMD_LOST_FOCUS:
			break;

		case APP_CMD_DESTROY:
			_queue.push_exit_event();
			break;
		}
	}

	s32 process_input(struct android_app *app, AInputEvent *event)
	{
		if (AInputEvent_getType(event) == AINPUT_EVENT_TYPE_MOTION) {
			const s32 action_raw = AMotionEvent_getAction(event);
			const s32 pointer_index = (action_raw & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK) >> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
			const s32 pointer_count = AMotionEvent_getPointerCount(event);

			const s32 pointer_id = AMotionEvent_getPointerId(event, pointer_index);
			const f32 x = AMotionEvent_getX(event, pointer_index);
			const f32 y = AMotionEvent_getY(event, pointer_index);

			const s32 action = (action_raw & AMOTION_EVENT_ACTION_MASK);

			switch (action) {
			case AMOTION_EVENT_ACTION_DOWN:
			case AMOTION_EVENT_ACTION_POINTER_DOWN:
				if (pointer_id < TouchButton::COUNT)
					_queue.push_button_event(InputDeviceType::TOUCHSCREEN, 0, pointer_id, true);
				if (pointer_id < TouchAxis::COUNT)
					_queue.push_axis_event(InputDeviceType::TOUCHSCREEN, 0, pointer_id, x, y, 0);
				break;

			case AMOTION_EVENT_ACTION_UP:
			case AMOTION_EVENT_ACTION_POINTER_UP:
				if (pointer_id < TouchAxis::COUNT)
					_queue.push_axis_event(InputDeviceType::TOUCHSCREEN, 0, pointer_id, x, y, 0);
				if (pointer_id < TouchButton::COUNT)
					_queue.push_button_event(InputDeviceType::TOUCHSCREEN, 0, pointer_id, false);
				break;

			case AMOTION_EVENT_ACTION_OUTSIDE:
			case AMOTION_EVENT_ACTION_CANCEL:
				if (pointer_id < TouchButton::COUNT)
					_queue.push_button_event(InputDeviceType::TOUCHSCREEN, 0, pointer_id, false);
				break;

			case AMOTION_EVENT_ACTION_MOVE:
				for (int index = 0; index < pointer_count; index++) {
					const s32 id = AMotionEvent_getPointerId(event, index);
					if (id < TouchAxis::COUNT) {
						const f32 xx = AMotionEvent_getX(event, index);
						const f32 yy = AMotionEvent_getY(event, index);
						_queue.push_axis_event(InputDeviceType::TOUCHSCREEN, 0, id, xx, yy, 0);
					}
				}
				break;
			}

			return 1;
		} else if (AInputEvent_getType(event) == AINPUT_EVENT_TYPE_KEY) {
			const s32 keycode   = AKeyEvent_getKeyCode(event);
			const s32 keyaction = AKeyEvent_getAction(event);

			if (keycode == AKEYCODE_BACK) {
				_queue.push_button_event(InputDeviceType::KEYBOARD
					, 0
					, KeyboardButton::ESCAPE
					, keyaction == AKEY_EVENT_ACTION_DOWN ? true : false
					);
			}

			return 1;
		}

		return 0;
	}

	static s32 on_input_event(struct android_app *app, AInputEvent *event)
	{
		return static_cast<AndroidDevice *>(app->userData)->process_input(app, event);
	}

	static void on_app_cmd(struct android_app *app, s32 cmd)
	{
		static_cast<AndroidDevice *>(app->userData)->process_command(app, cmd);
	}
};

static AndroidDevice *s_android_device;

struct WindowAndroid : public Window
{
	WindowAndroid()
	{
	}

	void open(u16 x, u16 y, u16 width, u16 height, u32 parent) override
	{
		CE_UNUSED_5(x, y, width, height, parent);
	}

	void close() override
	{
	}

	void show() override
	{
	}

	void hide() override
	{
	}

	void resize(u16 width, u16 height) override
	{
		CE_UNUSED_2(width, height);
	}

	void move(u16 x, u16 y) override
	{
		CE_UNUSED_2(x, y);
	}

	void minimize() override
	{
	}

	void maximize() override
	{
	}

	void restore() override
	{
	}

	const char *title() override
	{
		return NULL;
	}

	void set_title(const char *title) override
	{
		CE_UNUSED(title);
	}

	void show_cursor(bool show) override
	{
		CE_UNUSED(show);
	}

	void set_fullscreen(bool fullscreen) override
	{
		CE_UNUSED(fullscreen);
	}

	void set_cursor(MouseCursor::Enum cursor) override
	{
		CE_UNUSED(cursor);
	}

	void set_cursor_mode(CursorMode::Enum mode) override
	{
		CE_UNUSED(mode);
	}

	void *native_handle() override
	{
		return s_android_device->_window;
	}

	void *native_display() override
	{
		return NULL;
	}
};

namespace window
{
	Window *create(Allocator &a)
	{
		return CE_NEW(a, WindowAndroid)();
	}

	void destroy(Allocator &a, Window &w)
	{
		CE_DELETE(a, &w);
	}

} // namespace window

struct DisplayAndroid : public Display
{
	void modes(Array<DisplayMode> &modes) override
	{
		CE_UNUSED(modes);
	}

	void set_mode(u32 id) override
	{
		CE_UNUSED(id);
	}
};

namespace display
{
	Display *create(Allocator &a)
	{
		return CE_NEW(a, DisplayAndroid)();
	}

	void destroy(Allocator &a, Display &d)
	{
		CE_DELETE(a, &d);
	}

} // namespace display

static bool push_event(const OsEvent &ev)
{
	return s_android_device->_events.push(ev);
}

bool next_event(OsEvent &ev)
{
	return s_android_device->_events.pop(ev);
}

} // namespace crown

void android_main(struct android_app *app)
{
	using namespace crown;

	memory_globals::init();
	guid_globals::init();

	DeviceOptions opts(default_allocator(), 0, NULL);
	opts._asset_manager = app->activity->assetManager;

	s_android_device = CE_NEW(default_allocator(), AndroidDevice)(default_allocator());
	s_android_device->run(app, opts);
	CE_DELETE(default_allocator(), s_android_device);

	guid_globals::shutdown();
	memory_globals::shutdown();
}

#endif // if CROWN_PLATFORM_ANDROID