path: root/src/sfwk-wpe.c

// Copyright (C) 2026 Arslaan Pathan
// This code contains excerpts from wpe-sdl-simple, which is released under MIT.
// The original source code is available here: https://github.com/aperezdc/wpe-sdl-simple
// See external_licenses/COPYING_wpe-sdl-simple.txt

#include "glib.h"
#include <SDL3/SDL_video.h>
#include <saffron.h>
#include <stdio.h>
#include <stdlib.h>
#include <wpe/webkit.h>
#include <SDL3/SDL.h>
#include <SDL3/SDL_egl.h>
#include <SDL3/SDL_opengles2.h>
#include <saffronwebkit.h>


G_DECLARE_FINAL_TYPE(WPEViewSDL3, wpe_view_sdl3, WPE, VIEW_SDL3, WPEView)
G_DECLARE_FINAL_TYPE(WPEToplevelSDL3, wpe_toplevel_sdl3, WPE, TOPLEVEL_SDL3, WPEToplevel)
G_DECLARE_FINAL_TYPE(WPEDisplaySDL3, wpe_display_sdl3, WPE, DISPLAY_SDL3, WPEDisplay)

G_DEFINE_FINAL_TYPE(WPEViewSDL3, wpe_view_sdl3, WPE_TYPE_VIEW)
G_DEFINE_FINAL_TYPE(WPEToplevelSDL3, wpe_toplevel_sdl3, WPE_TYPE_TOPLEVEL)
G_DEFINE_FINAL_TYPE(WPEDisplaySDL3, wpe_display_sdl3, WPE_TYPE_DISPLAY)

static void
wpe_toplevel_sdl3_ensure_texture(WPEToplevelSDL3 *self, SDL_Renderer* renderer, SDL_PixelFormat format, int width, int height)
{
	if (self->texture) {
		if (self->texture->format == format && self->texture->w == width && self->texture->h == height)
			return;
		g_debug("%s: toplevel=%p, format=%#x, size=%dx%d, re-creating texture", G_STRFUNC, self, format, width, height);
		SDL_DestroyTexture(self->texture);
	}

	self->texture = SDL_CreateTexture(renderer, format, SDL_TEXTUREACCESS_STREAMING, width, height);
	g_assert(self->texture);
}

static gboolean
wpe_toplevel_sdl3_render(WPEToplevelSDL3 *self, SDL_Renderer* renderer, WPEView *view [[maybe_unused]], WPEBuffer *buffer, GError **error)
{
	// g_debug("%s: toplevel=%p, view=%p, buffer=%p is a %s", G_STRFUNC, self, view, buffer, G_OBJECT_TYPE_NAME(buffer));

	int buffer_width = wpe_buffer_get_width(buffer);
	int buffer_height = wpe_buffer_get_height(buffer);

	if (buffer) {
		WPEDisplaySDL3 *display = (WPEDisplaySDL3*) wpe_toplevel_get_display((WPEToplevel*) self);
		EGLImage image = wpe_buffer_import_to_egl_image(buffer, error);
		if (image != EGL_NO_IMAGE && display->imageTargetTexture2DOES) {
			g_assert(display->egl_display == SDL_EGL_GetCurrentDisplay());
			wpe_toplevel_sdl3_ensure_texture(self, renderer, SDL_PIXELFORMAT_EXTERNAL_OES, buffer_width, buffer_height);
			SDL_PropertiesID texture_props = SDL_GetTextureProperties(self->texture);
			int texture_id = SDL_GetNumberProperty(texture_props, SDL_PROP_TEXTURE_OPENGL_TEXTURE_NUMBER, 0);
			SDL_DestroyProperties(texture_props);
			glBindTexture(GL_TEXTURE_2D, texture_id);
			display->imageTargetTexture2DOES(GL_TEXTURE_2D, image);
		} else if (g_error_matches(*error, WPE_BUFFER_ERROR, WPE_BUFFER_ERROR_NOT_SUPPORTED)) {
			g_clear_error(error);
			GBytes *bytes = wpe_buffer_import_to_pixels(buffer, error);
			if (!bytes) {
				g_set_error_literal(error, WPE_VIEW_ERROR, WPE_VIEW_ERROR_RENDER_FAILED,
						"Cannot import buffer pixel data");
				return FALSE;
			}
			wpe_toplevel_sdl3_ensure_texture(self, renderer, SDL_PIXELFORMAT_BGRA32, buffer_width, buffer_height);
			// TODO: Update only the damaged rectangles.
			void *pixels = NULL;
			int stride = 0;
			if (!SDL_LockTexture(self->texture, NULL, &pixels, &stride)) {
				g_set_error(error, WPE_VIEW_ERROR, WPE_VIEW_ERROR_RENDER_FAILED,
						"Cannot lock SDL texture to update from SHM buffer: %s", SDL_GetError());
				return FALSE;
			}
			size_t size;
			const void *source = g_bytes_get_data(bytes, &size);
			if (stride == buffer_width * 4) {
				memcpy(pixels, source, size);
			} else {
				for (unsigned i = 0; i < buffer_height; i++) {
					memcpy(pixels, source, buffer_width * 4);
					pixels = (void*) ((uintptr_t) pixels + stride);
					source = (const void*) ((uintptr_t) source + buffer_width * 4);
				}
			}
			SDL_UnlockTexture(self->texture);
		} else {
			g_set_error_literal(error, WPE_VIEW_ERROR, WPE_VIEW_ERROR_RENDER_FAILED,
					"Cannot import buffer as EGLImage, nor import pixel data");
			return FALSE;
		}
		if (image != EGL_NO_IMAGE)
			display->destroyImage(display->egl_display, image);

		// At this point the SDL_Texture contains the data to render.
		if (!SDL_RenderTexture(renderer, self->texture, NULL, NULL)) {
			g_set_error(error, WPE_VIEW_ERROR, WPE_VIEW_ERROR_RENDER_FAILED,
					"Cannot render SDL texture: %s", SDL_GetError());
			return FALSE;
		}
	} else {
		SDL_SetRenderDrawColor(renderer, 255, 255, 255, SDL_ALPHA_OPAQUE);
		SDL_RenderClear(renderer);
	}

	SDL_RenderPresent(renderer);
	return TRUE;
}

static gboolean
wpe_view_sdl3_render_buffer(WPEView *view, WPEBuffer *buffer, const WPERectangle *damage_rects, unsigned n_damage_rects, GError **error)
{
	WPEToplevel *toplevel = wpe_view_get_toplevel(view);
	g_assert(WPE_IS_TOPLEVEL_SDL3(toplevel));

	WPEViewSDL3* view_impl = (WPEViewSDL3*)view;
	SFWKWebView* webview = (SFWKWebView*)view_impl->userdata;
	SDL_Renderer* renderer = webview->renderer;

	if (!wpe_toplevel_sdl3_render((WPEToplevelSDL3*) toplevel, renderer, view, buffer, error))
		return FALSE;

	wpe_view_buffer_rendered(view, buffer);
	wpe_view_buffer_released(view, buffer);
	return TRUE;
}

static void
wpe_view_sdl3_on_notify_toplevel(WPEView *view)
{
	WPEToplevel *toplevel = wpe_view_get_toplevel(view);
	if (toplevel) {
		((WPEToplevelSDL3*) toplevel)->view = view;
		int width, height;
		wpe_toplevel_get_size(toplevel, &width, &height);
		if (width && height)
			wpe_view_resized(view, width, height);
		wpe_view_map(view);
	} else {
		wpe_view_unmap(view);
	}
}

static void
wpe_view_sdl3_constructed(GObject *object)
{
	G_OBJECT_CLASS(wpe_view_sdl3_parent_class)->constructed(object);
	g_signal_connect(object, "notify::toplevel", G_CALLBACK(wpe_view_sdl3_on_notify_toplevel), NULL);
	g_debug("%s: view=%p", G_STRFUNC, object);
}

static void
wpe_view_sdl3_dispose(GObject *object)
{
	g_debug("%s: view=%p", G_STRFUNC, object);
	G_OBJECT_CLASS(wpe_view_sdl3_parent_class)->dispose(object);
}

static void
wpe_view_sdl3_init(WPEViewSDL3 *self)
{
}

static void
wpe_view_sdl3_class_init(WPEViewSDL3Class *klass)
{
	GObjectClass *object_class = G_OBJECT_CLASS(klass);
	object_class->constructed = wpe_view_sdl3_constructed;
	object_class->dispose = wpe_view_sdl3_dispose;

	WPEViewClass *view_class = WPE_VIEW_CLASS(klass);
	view_class->render_buffer = wpe_view_sdl3_render_buffer;
}

static void
wpe_toplevel_sdl3_init(WPEToplevelSDL3 *self)
{
}

static WPEView*
wpe_view_sdl3_new(WPEDisplay *display)
{
	g_return_val_if_fail(WPE_IS_DISPLAY_SDL3(display), NULL);
	return g_object_new(wpe_view_sdl3_get_type(), "display", display, NULL);
}


static gboolean
wpe_toplevel_sdl3_each_view_resized(WPEToplevel *toplevel, WPEView *view, void *userdata)
{
	int width, height;
	wpe_toplevel_get_size(toplevel, &width, &height);
	wpe_view_resized(view, width, height);
	return FALSE;  // Continue iterating views.
}

// static gboolean
// wpe_toplevel_sdl3_set_fullscreen(WPEToplevel *toplevel, gboolean fullscreen)
// {
// 	WPEToplevelSDL3 *self = WPE_TOPLEVEL_SDL3(toplevel);
// 	if (!SDL_SetWindowFullscreen(self->window, !!fullscreen))
// 		g_warning("Could not %s SDL window for toplevel %p",
// 				fullscreen ? "fullscreen" : "un-fullscreen",
// 				toplevel);
// 		return FALSE;
//
// 	WPEToplevelState state = wpe_toplevel_get_state(toplevel);
// 	if (fullscreen)
// 		state |= WPE_TOPLEVEL_STATE_FULLSCREEN;
// 	else
// 		state &= ~WPE_TOPLEVEL_STATE_FULLSCREEN;
// 	wpe_toplevel_state_changed(toplevel, state);
// 	return TRUE;
// }

// static void
// wpe_toplevel_sdl3_set_title(WPEToplevel *toplevel, const char *title)
// {
// 	WPEToplevelSDL3 *self = WPE_TOPLEVEL_SDL3(toplevel);
// 	if (self->window)
// 		SDL_SetWindowTitle(self->window, title ? title : SDL_GetAppMetadataProperty(SDL_PROP_APP_METADATA_NAME_STRING));
// }

// static gboolean
// wpe_toplevel_sdl3_resize(WPEToplevel *toplevel, int width, int height)
// {
// 	WPEToplevelSDL3 *self = WPE_TOPLEVEL_SDL3(toplevel);
// 	if (!SDL_SetWindowSize(self->window, width, height)) {
// 		g_warning("Could not resize SDL window for toplevel %p: %s", self, SDL_GetError());
// 		return FALSE;
// 	}
//
// 	wpe_toplevel_resized(toplevel, width, height);
// 	wpe_toplevel_foreach_view(toplevel, wpe_toplevel_sdl3_each_view_resized, NULL);
// 	return TRUE;
// }

static void
wpe_toplevel_sdl3_constructed(GObject *object)
{
	G_OBJECT_CLASS(wpe_toplevel_sdl3_parent_class)->constructed(object);
}

// what the fuck is this
// im just going to steal this function and put it in my bindings
// GLib is so confusing T_T
//
// coming back: i think this like, removes a view? e.g. closing a tab or smth
static gboolean
wpe_toplevel_sdl3_each_view_detach(WPEToplevel *toplevel [[maybe_unused]], WPEView *view, void *userdata [[maybe_unused]])
{
	wpe_view_set_toplevel(view, NULL);
	return FALSE;  // Continue iterating views.
}

static void
wpe_toplevel_sdl3_dispose(GObject *object)
{
	WPEToplevelSDL3 *self = WPE_TOPLEVEL_SDL3(object);
	g_debug("%s: toplevel=%p", G_STRFUNC, self);

	wpe_toplevel_foreach_view(WPE_TOPLEVEL(object), wpe_toplevel_sdl3_each_view_detach, NULL);

	g_clear_pointer(&self->texture, SDL_DestroyTexture);

	G_OBJECT_CLASS(wpe_toplevel_sdl3_parent_class)->dispose(object);
}

static void
wpe_toplevel_sdl3_class_init(WPEToplevelSDL3Class *klass)
{
	GObjectClass *object_class = G_OBJECT_CLASS(klass);
	object_class->constructed = wpe_toplevel_sdl3_constructed;
	object_class->finalize = wpe_toplevel_sdl3_dispose;

	WPEToplevelClass *toplevel_class = WPE_TOPLEVEL_CLASS(klass);
	// TODO add handlers for this in the future, maybe let the user hook into them with the abstractions
	// toplevel_class->set_fullscreen = wpe_toplevel_sdl3_set_fullscreen;
	// toplevel_class->set_title = wpe_toplevel_sdl3_set_title;
	// toplevel_class->resize = wpe_toplevel_sdl3_resize;
}

static WPEToplevel*
wpe_toplevel_sdl3_new(WPEDisplay *display)
{
	g_return_val_if_fail(WPE_IS_DISPLAY_SDL3(display), NULL);
	return g_object_new(wpe_toplevel_sdl3_get_type(), "display", display, "max-views", 1, NULL);
}

static WPEView*
wpe_toplevel_sdl3_get_view(WPEToplevelSDL3 *self)
{
	return wpe_toplevel_get_n_views((WPEToplevel*) self) ? self->view : NULL;
}

static void
wpe_display_sdl3_finalize(GObject *object)
{
	WPEDisplaySDL3 *self = WPE_DISPLAY_SDL3(object);
	g_debug("%s: display=%p", G_STRFUNC, self);

	self->egl_display = EGL_NO_DISPLAY;
	self->destroyImage = NULL;
	self->imageTargetTexture2DOES = NULL;

	g_clear_pointer(&self->gl_context, SDL_GL_DestroyContext);
	g_clear_pointer(&self->hidden_window, SDL_DestroyWindow);

	if (self->init_flags) {
		SDL_QuitSubSystem(self->init_flags);
		self->init_flags = 0;
	}

	G_OBJECT_CLASS(wpe_display_sdl3_parent_class)->finalize(object);
}

static gboolean
wpe_display_sdl3_connect(WPEDisplay *display, GError **error)
{
	WPEDisplaySDL3 *self = WPE_DISPLAY_SDL3(display);

	if (!SDL_WasInit(SDL_INIT_EVENTS))
		self->init_flags |= SDL_INIT_EVENTS;
	if (!SDL_WasInit(SDL_INIT_VIDEO))
		self->init_flags |= SDL_INIT_VIDEO;

	if (self->init_flags && !SDL_Init(self->init_flags)) {
		g_set_error(error, WPE_DISPLAY_ERROR, WPE_DISPLAY_ERROR_CONNECTION_FAILED,
				"Could not initialize SDL: %s", SDL_GetError());
		return FALSE;
	}

	if (!(self->hidden_window = SDL_CreateWindow("Dummy", 1, 1, SDL_WINDOW_HIDDEN | SDL_WINDOW_OPENGL))) {
		g_set_error(error, WPE_DISPLAY_ERROR, WPE_DISPLAY_ERROR_CONNECTION_FAILED,
				"Could not create SDL hidden window: %s", SDL_GetError());
		return FALSE;
	}

	if (!(self->gl_context = SDL_GL_CreateContext(self->hidden_window))) {
		g_set_error(error, WPE_DISPLAY_ERROR, WPE_DISPLAY_ERROR_CONNECTION_FAILED,
				"Could not create SDL-managed EGL context: %s", SDL_GetError());
		return FALSE;
	}
	SDL_GL_MakeCurrent(self->hidden_window, self->gl_context);

	if (!SDL_SyncWindow(self->hidden_window)) {
		g_set_error(error, WPE_DISPLAY_ERROR, WPE_DISPLAY_ERROR_CONNECTION_FAILED,
				"Could not sync hidden SDL window: %s", SDL_GetError());
		return FALSE;
	}

	if ((self->egl_display = SDL_EGL_GetCurrentDisplay()) == EGL_NO_DISPLAY) {
		g_set_error(error, WPE_DISPLAY_ERROR, WPE_DISPLAY_ERROR_CONNECTION_FAILED,
				"Could not get SDL-managed EGL display: %s", SDL_GetError());
		return FALSE;
	}

	self->destroyImage = (PFNEGLDESTROYIMAGEKHRPROC)
		SDL_EGL_GetProcAddress("eglDestroyImageKHR");
	self->imageTargetTexture2DOES = (PFNGLEGLIMAGETARGETTEXTURE2DOESPROC)
		SDL_EGL_GetProcAddress("glEGLImageTargetTexture2DOES");
	g_debug("%s: done, eglDestroyImageKHR=%p, glEGLImageTargetTexture2DOES=%p", G_STRFUNC,
            self->destroyImage, self->imageTargetTexture2DOES);

	if (!self->destroyImage) {
		g_set_error_literal(error, WPE_DISPLAY_ERROR, WPE_DISPLAY_ERROR_CONNECTION_FAILED,
				"EGL does not support eglDestroyImageKHR");
		return FALSE;
	}

	return TRUE;
}

static EGLDisplay
wpe_display_sdl3_get_egl_display(WPEDisplay *display, GError **error [[maybe_unused]])
{
	WPEDisplaySDL3 *self = WPE_DISPLAY_SDL3(display);
	return self->egl_display;
}
//
// creates a new wpe view and toplevel
// oh and don't forget, GLib black magic
// yaaayyyyyyyyyyyy... we love glib (sarc)
static WPEView*
wpe_display_sdl3_create_view(WPEDisplay *display)
{
	g_autoptr(WPEView) view = wpe_view_sdl3_new(display);

	const gboolean create_toplevel = wpe_settings_get_boolean(wpe_display_get_settings(display), WPE_SETTING_CREATE_VIEWS_WITH_A_TOPLEVEL, NULL);
	if (create_toplevel) {
		g_autoptr(WPEToplevel) toplevel = wpe_toplevel_sdl3_new(display);
		wpe_view_set_toplevel(view, toplevel);
	}

	return g_steal_pointer(&view);
}

// initializes the WPEDisplaySDL3Class class? what is this sh*t? why did they have to use GLib for the WPE api?
// WHY IGALIA WHYYYYYYYY
static void
wpe_display_sdl3_class_init(WPEDisplaySDL3Class *klass)
{
	GObjectClass *object_class = G_OBJECT_CLASS(klass);
	object_class->finalize = wpe_display_sdl3_finalize;

	WPEDisplayClass *display_class = WPE_DISPLAY_CLASS(klass);
	display_class->connect = wpe_display_sdl3_connect;
	display_class->get_egl_display = wpe_display_sdl3_get_egl_display;
	display_class->create_view = wpe_display_sdl3_create_view;
}

static void
wpe_display_sdl3_init(WPEDisplaySDL3 *self)
{
	g_debug("%s: display=%p", G_STRFUNC, self);
}

// if the webview has a new title, go call that function that i annotated like 10 years ago and do the thing
static void
handle_web_view_notify_title(WebKitWebView *web_view)
{
	const char *title = webkit_web_view_get_title(web_view);
	if (!(title && *title))
		title = SDL_GetAppMetadataProperty(SDL_PROP_APP_METADATA_NAME_STRING);

	g_message("View<%p>.title = %s", web_view, title);

	WPEView *view = webkit_web_view_get_wpe_view(web_view);
	wpe_toplevel_set_title(wpe_view_get_toplevel(view), title);
}

static WebKitWebView* handle_web_view_create(WebKitWebView*, WebKitNavigationAction*, SFWKContext*);


static void
free_weak_ref(void *ptr)
{
	GWeakRef *ref = ptr;
	g_weak_ref_clear(ref);
	g_free(ref);
}

static WebKitWebView*
context_add_web_view(SFWKContext* self, WebKitWebView *related_view, const char *uri)
{
	g_autoptr(WebKitWebView) view = g_object_new(WEBKIT_TYPE_WEB_VIEW,
			"display", self->display,
			"related-view", related_view,
			NULL);

	GWeakRef *view_ref = g_new0(GWeakRef, 1);
	g_weak_ref_init(view_ref, view);
	g_object_set_data_full(G_OBJECT(webkit_web_view_get_wpe_view(view)), "weak-web-view", view_ref, free_weak_ref);

	g_signal_connect(view, "notify::title", G_CALLBACK(handle_web_view_notify_title), NULL);
	g_signal_connect(view, "create", G_CALLBACK(handle_web_view_create), self);

	if (uri)
		webkit_web_view_load_uri(view, uri);

	return g_steal_pointer(&view);
}

static WebKitWebView*
handle_web_view_create(WebKitWebView *view, WebKitNavigationAction *action [[maybe_unused]], SFWKContext *context)
{
	return context_add_web_view(context, view, NULL);
}

// map SDL buttons to WPE buttons
static unsigned
wpe_button_for_sdl_button(unsigned index)
{
	switch (index) {
	case 1: return WPE_BUTTON_PRIMARY;
	case 2: return WPE_BUTTON_MIDDLE;
	case 3: return WPE_BUTTON_SECONDARY;
	default: return 0;
	}
}

// map SDL keymodifiers to WPE mods
static WPEModifiers
wpe_modifiers_for_sdl_keymod(SDL_Keymod keymod)
{
	WPEModifiers result = 0;
	if (keymod & SDL_KMOD_CTRL)
		result |= WPE_MODIFIER_KEYBOARD_CONTROL;
	if (keymod & SDL_KMOD_SHIFT)
		result |= WPE_MODIFIER_KEYBOARD_SHIFT;
	if (keymod & SDL_KMOD_ALT)
		result |= WPE_MODIFIER_KEYBOARD_ALT;
	if (keymod & SDL_KMOD_GUI)
		result |= WPE_MODIFIER_KEYBOARD_META;
	if (keymod & SDL_KMOD_CAPS)
		result |= WPE_MODIFIER_KEYBOARD_CAPS_LOCK;
	return result;
}

SFWKContext* sfwk_init() {
	g_io_extension_point_register(WPE_DISPLAY_EXTENSION_POINT_NAME);
	g_io_extension_point_implement(WPE_DISPLAY_EXTENSION_POINT_NAME, wpe_display_sdl3_get_type(), "sdl3", 200);

	SFWKContext* context = g_new0(SFWKContext, 1);
	context->main_context = g_main_context_new_with_flags(G_MAIN_CONTEXT_FLAGS_OWNERLESS_POLLING);

	g_autoptr(GError) error = NULL;

	context->display = g_object_new(wpe_display_sdl3_get_type(), NULL);
	if (!wpe_display_connect(context->display, &error)) {
		g_printerr("cant connect to display T_T %s\n", error->message);
		g_clear_object(&context->display);
		g_clear_pointer(&context->main_context, g_main_context_unref);
		g_free(context);
		return NULL;
	}

	return context;
}

static void sfwk_webview_draw(SaffronWidget* widget, SDL_Renderer* renderer) {
    SFWKWebView* webview = (SFWKWebView*)widget;
    webview->renderer = renderer;
    
    WPEToplevelSDL3 *toplevel = (WPEToplevelSDL3*)webview->toplevel;
    if (toplevel->texture) {
        SDL_RenderTexture(renderer, toplevel->texture, NULL, NULL);
    }
}

void sfwk_process_event(SFWKContext *context, SFWKWebView* webview, SDL_Event *event) {
	WPEToplevel* toplevel = webview->toplevel;
	// for some reason we're doing this weird sh*t? we could just use webview->view but oh well
	WPEView *view = toplevel ? wpe_toplevel_sdl3_get_view((WPEToplevelSDL3*) toplevel) : NULL;
}

SFWKWebView* sfwk_webview_new(SFWKContext* context, const char* url, int w, int h) {
	SFWKWebView* webview = malloc(sizeof(SFWKWebView));
	if (!webview) return NULL; // good fucking luck
				   //
	saffron_widget_init((SaffronWidget*)webview);
	((SaffronWidget*)webview)->type = SAFFRON_WIDGET_UNKNOWN; // saffron does not have a builtin for webviews, and i cant be bothered to add one because "if you have to edit the library, it's not extensible" - arslaan 2026
	((SaffronWidget*)webview)->w = w;
	((SaffronWidget*)webview)->h = h;
	((SaffronWidget*)webview)->draw = sfwk_webview_draw;
	// add an on_resize here
	
	webview->toplevel = wpe_toplevel_sdl3_new(context->display);
	
	webview->wpeview = wpe_view_sdl3_new(context->display);
	((WPEViewSDL3*)webview->wpeview)->userdata = webview;
	wpe_view_set_toplevel(webview->wpeview, webview->toplevel);

	webview->wkwebview = g_object_new(WEBKIT_TYPE_WEB_VIEW, "display", context->display, NULL);
	webkit_web_view_load_uri(webview->wkwebview, url);

	return webview;
}