webview.h

/*
 * MIT License
 *
 * Copyright (c) 2017 Serge Zaitsev
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#ifndef WEBVIEW_H
#define WEBVIEW_H

#ifdef __cplusplus
extern "C" {
#endif

#ifdef WEBVIEW_STATIC
#define WEBVIEW_API static
#else
#if defined(WEBVIEW_WINAPI)
#define WEBVIEW_API extern __declspec(dllexport)
#else
#define WEBVIEW_API extern
#endif
#endif

#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#if defined(WEBVIEW_GTK)
#include <JavaScriptCore/JavaScript.h>
#include <gtk/gtk.h>
#include <webkit2/webkit2.h>

struct webview_priv {
  GtkWidget *window;
  GtkWidget *scroller;
  GtkWidget *webview;
  GtkWidget *inspector_window;
  GAsyncQueue *queue;
  int ready;
  int js_busy;
  int should_exit;
};
#elif defined(WEBVIEW_WINAPI)
#define CINTERFACE
#include <windows.h>

#include <commctrl.h>
#include <exdisp.h>
#include <mshtmhst.h>
#include <mshtml.h>
#include <shobjidl.h>

#include <stdio.h>

struct webview_priv {
  HWND hwnd;
  IOleObject **browser;
  BOOL is_fullscreen;
  DWORD saved_style;
  DWORD saved_ex_style;
  RECT saved_rect;
};
#elif defined(WEBVIEW_COCOA)
#include <objc/objc-runtime.h>
#include <CoreGraphics/CoreGraphics.h>
#include <limits.h>

struct webview_priv {
  id pool;
  id window;
  id webview;
  id windowDelegate;
  int should_exit;
};
#else
#error "Define one of: WEBVIEW_GTK, WEBVIEW_COCOA or WEBVIEW_WINAPI"
#endif

struct webview;

typedef void (*webview_external_invoke_cb_t)(struct webview *w,
                                             const char *arg);

struct webview {
  const char *url;
  const char *title;
  int width;
  int height;
  int resizable;
  int debug;
  webview_external_invoke_cb_t external_invoke_cb;
  struct webview_priv priv;
  void *userdata;
};

enum webview_dialog_type {
  WEBVIEW_DIALOG_TYPE_OPEN = 0,
  WEBVIEW_DIALOG_TYPE_SAVE = 1,
  WEBVIEW_DIALOG_TYPE_ALERT = 2
};

#define WEBVIEW_DIALOG_FLAG_FILE (0 << 0)
#define WEBVIEW_DIALOG_FLAG_DIRECTORY (1 << 0)

#define WEBVIEW_DIALOG_FLAG_INFO (1 << 1)
#define WEBVIEW_DIALOG_FLAG_WARNING (2 << 1)
#define WEBVIEW_DIALOG_FLAG_ERROR (3 << 1)
#define WEBVIEW_DIALOG_FLAG_ALERT_MASK (3 << 1)

typedef void (*webview_dispatch_fn)(struct webview *w, void *arg);

struct webview_dispatch_arg {
  webview_dispatch_fn fn;
  struct webview *w;
  void *arg;
};

#define DEFAULT_URL                                                            \
  "data:text/"                                                                 \
  "html,%3C%21DOCTYPE%20html%3E%0A%3Chtml%20lang=%22en%22%3E%0A%3Chead%3E%"    \
  "3Cmeta%20charset=%22utf-8%22%3E%3Cmeta%20http-equiv=%22X-UA-Compatible%22%" \
  "20content=%22IE=edge%22%3E%3C%2Fhead%3E%0A%3Cbody%3E%3Cdiv%20id=%22app%22%" \
  "3E%3C%2Fdiv%3E%3Cscript%20type=%22text%2Fjavascript%22%3E%3C%2Fscript%3E%"  \
  "3C%2Fbody%3E%0A%3C%2Fhtml%3E"

#define CSS_INJECT_FUNCTION                                                    \
  "(function(e){var "                                                          \
  "t=document.createElement('style'),d=document.head||document."               \
  "getElementsByTagName('head')[0];t.setAttribute('type','text/"               \
  "css'),t.styleSheet?t.styleSheet.cssText=e:t.appendChild(document."          \
  "createTextNode(e)),d.appendChild(t)})"

static const char *webview_check_url(const char *url) {
  if (url == NULL || strlen(url) == 0) {
    return DEFAULT_URL;
  }
  return url;
}

WEBVIEW_API int webview(const char *title, const char *url, int width,
                        int height, int resizable);

WEBVIEW_API struct webview* webview_alloc(const char* title, const char* url,
                                          int width, int height,
                                          int resizable, int debug,
                                          webview_external_invoke_cb_t cb);
WEBVIEW_API void webview_release(struct webview* webview);

WEBVIEW_API int webview_init(struct webview *w);
WEBVIEW_API int webview_loop(struct webview *w, int blocking);
WEBVIEW_API int webview_eval(struct webview *w, const char *js);
WEBVIEW_API int webview_inject_css(struct webview *w, const char *css);
WEBVIEW_API void webview_set_title(struct webview *w, const char *title);
WEBVIEW_API void webview_set_fullscreen(struct webview *w, int fullscreen);
WEBVIEW_API void webview_set_color(struct webview *w, uint8_t r, uint8_t g,
                                   uint8_t b, uint8_t a);
WEBVIEW_API void webview_dialog(struct webview *w,
                                enum webview_dialog_type dlgtype, int flags,
                                const char *title, const char *arg,
                                char *result, size_t resultsz);
WEBVIEW_API void webview_dispatch(struct webview *w, webview_dispatch_fn fn,
                                  void *arg);
WEBVIEW_API void webview_terminate(struct webview *w);
WEBVIEW_API void webview_exit(struct webview *w);
WEBVIEW_API void webview_debug(const char *format, ...);
WEBVIEW_API void webview_print_log(const char *s);

WEBVIEW_API void webview_set_userdata(struct webview* w, void* userdata);
WEBVIEW_API void* webview_get_userdata(struct webview* w);

#ifdef WEBVIEW_IMPLEMENTATION
#undef WEBVIEW_IMPLEMENTATION

WEBVIEW_API int webview(const char *title, const char *url, int width,
                        int height, int resizable) {
  struct webview webview;
  memset(&webview, 0, sizeof(webview));
  webview.title = title;
  webview.url = url;
  webview.width = width;
  webview.height = height;
  webview.resizable = resizable;
  int r = webview_init(&webview);
  if (r != 0) {
    return r;
  }
  while (webview_loop(&webview, 1) == 0) {
  }
  webview_exit(&webview);
  return 0;
}

WEBVIEW_API struct webview* webview_alloc(const char* title, const char* url,
                                          int width, int height,
                                          int resizable, int debug,
                                          webview_external_invoke_cb_t cb) {
  struct webview* webview = (struct webview*)calloc(1, sizeof(*webview));
  webview->title = title;
  webview->url = url;
  webview->width = width;
  webview->height = height;
  webview->resizable = resizable;
  webview->debug = debug;
  webview->external_invoke_cb = cb;

  int r = webview_init(webview);
  if (r != 0) {
    webview_release(webview);
    return NULL;
  }
  
  return webview;
}

WEBVIEW_API void webview_release(struct webview* webview) {
  free(webview);
}

WEBVIEW_API void webview_set_userdata(struct webview* w, void* ud)
{
  w->userdata = ud;
}

WEBVIEW_API void* webview_get_userdata(struct webview* w)
{
  return w->userdata;
}

WEBVIEW_API void webview_debug(const char *format, ...) {
  char buf[4096];
  va_list ap;
  va_start(ap, format);
  vsnprintf(buf, sizeof(buf), format, ap);
  webview_print_log(buf);
  va_end(ap);
}

static int webview_js_encode(const char *s, char *esc, size_t n) {
  int r = 1; /* At least one byte for trailing zero */
  for (; *s; s++) {
    const unsigned char c = *s;
    if (c >= 0x20 && c < 0x80 && strchr("<>\\'\"", c) == NULL) {
      if (n > 0) {
        *esc++ = c;
        n--;
      }
      r++;
    } else {
      if (n > 0) {
        snprintf(esc, n, "\\x%02x", (int)c);
        esc += 4;
        n -= 4;
      }
      r += 4;
    }
  }
  return r;
}

WEBVIEW_API int webview_inject_css(struct webview *w, const char *css) {
  int n = webview_js_encode(css, NULL, 0);
  char *esc = (char *)calloc(1, sizeof(CSS_INJECT_FUNCTION) + n + 4);
  if (esc == NULL) {
    return -1;
  }
  char *js = (char *)calloc(1, n);
  webview_js_encode(css, js, n);
  snprintf(esc, sizeof(CSS_INJECT_FUNCTION) + n + 4, "%s(\"%s\")",
           CSS_INJECT_FUNCTION, js);
  int r = webview_eval(w, esc);
  free(js);
  free(esc);
  return r;
}

#if defined(WEBVIEW_GTK)
static void external_message_received_cb(WebKitUserContentManager *m,
                                         WebKitJavascriptResult *r,
                                         gpointer arg) {
  (void)m;
  struct webview *w = (struct webview *)arg;
  if (w->external_invoke_cb == NULL) {
    return;
  }
  JSGlobalContextRef context = webkit_javascript_result_get_global_context(r);
  JSValueRef value = webkit_javascript_result_get_value(r);
  JSStringRef js = JSValueToStringCopy(context, value, NULL);
  size_t n = JSStringGetMaximumUTF8CStringSize(js);
  char *s = g_new(char, n);
  JSStringGetUTF8CString(js, s, n);
  w->external_invoke_cb(w, s);
  JSStringRelease(js);
  g_free(s);
}

static void webview_load_changed_cb(WebKitWebView *webview,
                                    WebKitLoadEvent event, gpointer arg) {
  (void)webview;
  struct webview *w = (struct webview *)arg;
  if (event == WEBKIT_LOAD_FINISHED) {
    w->priv.ready = 1;
  }
}

static void webview_destroy_cb(GtkWidget *widget, gpointer arg) {
  (void)widget;
  struct webview *w = (struct webview *)arg;
  webview_terminate(w);
}

static gboolean webview_context_menu_cb(WebKitWebView *webview,
                                        GtkWidget *default_menu,
                                        WebKitHitTestResult *hit_test_result,
                                        gboolean triggered_with_keyboard,
                                        gpointer userdata) {
  (void)webview;
  (void)default_menu;
  (void)hit_test_result;
  (void)triggered_with_keyboard;
  (void)userdata;
  return TRUE;
}

WEBVIEW_API int webview_init(struct webview *w) {
  if (gtk_init_check(0, NULL) == FALSE) {
    return -1;
  }

  w->priv.ready = 0;
  w->priv.should_exit = 0;
  w->priv.queue = g_async_queue_new();
  w->priv.window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_window_set_title(GTK_WINDOW(w->priv.window), w->title);

  if (w->resizable) {
    gtk_window_set_default_size(GTK_WINDOW(w->priv.window), w->width,
                                w->height);
  } else {
    gtk_widget_set_size_request(w->priv.window, w->width, w->height);
  }
  gtk_window_set_resizable(GTK_WINDOW(w->priv.window), !!w->resizable);
  gtk_window_set_position(GTK_WINDOW(w->priv.window), GTK_WIN_POS_CENTER);

  w->priv.scroller = gtk_scrolled_window_new(NULL, NULL);
  gtk_container_add(GTK_CONTAINER(w->priv.window), w->priv.scroller);

  WebKitUserContentManager *m = webkit_user_content_manager_new();
  webkit_user_content_manager_register_script_message_handler(m, "external");
  g_signal_connect(m, "script-message-received::external",
                   G_CALLBACK(external_message_received_cb), w);

  w->priv.webview = webkit_web_view_new_with_user_content_manager(m);
  webkit_web_view_load_uri(WEBKIT_WEB_VIEW(w->priv.webview),
                           webview_check_url(w->url));
  g_signal_connect(G_OBJECT(w->priv.webview), "load-changed",
                   G_CALLBACK(webview_load_changed_cb), w);
  gtk_container_add(GTK_CONTAINER(w->priv.scroller), w->priv.webview);

  if (w->debug) {
    WebKitSettings *settings =
        webkit_web_view_get_settings(WEBKIT_WEB_VIEW(w->priv.webview));
    webkit_settings_set_enable_write_console_messages_to_stdout(settings, true);
    webkit_settings_set_enable_developer_extras(settings, true);
  } else {
    g_signal_connect(G_OBJECT(w->priv.webview), "context-menu",
                     G_CALLBACK(webview_context_menu_cb), w);
  }

  gtk_widget_show_all(w->priv.window);

  webkit_web_view_run_javascript(
      WEBKIT_WEB_VIEW(w->priv.webview),
      "window.external={invoke:function(x){"
      "window.webkit.messageHandlers.external.postMessage(x);}}",
      NULL, NULL, NULL);

  g_signal_connect(G_OBJECT(w->priv.window), "destroy",
                   G_CALLBACK(webview_destroy_cb), w);
  return 0;
}

WEBVIEW_API int webview_loop(struct webview *w, int blocking) {
  gtk_main_iteration_do(blocking);
  return w->priv.should_exit;
}

WEBVIEW_API void webview_set_title(struct webview *w, const char *title) {
  gtk_window_set_title(GTK_WINDOW(w->priv.window), title);
}

WEBVIEW_API void webview_set_fullscreen(struct webview *w, int fullscreen) {
  if (fullscreen) {
    gtk_window_fullscreen(GTK_WINDOW(w->priv.window));
  } else {
    gtk_window_unfullscreen(GTK_WINDOW(w->priv.window));
  }
}

WEBVIEW_API void webview_set_color(struct webview *w, uint8_t r, uint8_t g,
                                   uint8_t b, uint8_t a) {
  GdkRGBA color = {r / 255.0, g / 255.0, b / 255.0, a / 255.0};
  webkit_web_view_set_background_color(WEBKIT_WEB_VIEW(w->priv.webview),
                                       &color);
}

WEBVIEW_API void webview_dialog(struct webview *w,
                                enum webview_dialog_type dlgtype, int flags,
                                const char *title, const char *arg,
                                char *result, size_t resultsz) {
  GtkWidget *dlg;
  if (result != NULL) {
    result[0] = '\0';
  }
  if (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN ||
      dlgtype == WEBVIEW_DIALOG_TYPE_SAVE) {
    dlg = gtk_file_chooser_dialog_new(
        title, GTK_WINDOW(w->priv.window),
        (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN
             ? (flags & WEBVIEW_DIALOG_FLAG_DIRECTORY
                    ? GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER
                    : GTK_FILE_CHOOSER_ACTION_OPEN)
             : GTK_FILE_CHOOSER_ACTION_SAVE),
        "_Cancel", GTK_RESPONSE_CANCEL,
        (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN ? "_Open" : "_Save"),
        GTK_RESPONSE_ACCEPT, NULL);
    gtk_file_chooser_set_local_only(GTK_FILE_CHOOSER(dlg), FALSE);
    gtk_file_chooser_set_select_multiple(GTK_FILE_CHOOSER(dlg), FALSE);
    gtk_file_chooser_set_show_hidden(GTK_FILE_CHOOSER(dlg), TRUE);
    gtk_file_chooser_set_do_overwrite_confirmation(GTK_FILE_CHOOSER(dlg), TRUE);
    gtk_file_chooser_set_create_folders(GTK_FILE_CHOOSER(dlg), TRUE);
    gint response = gtk_dialog_run(GTK_DIALOG(dlg));
    if (response == GTK_RESPONSE_ACCEPT) {
      gchar *filename = gtk_file_chooser_get_filename(GTK_FILE_CHOOSER(dlg));
      g_strlcpy(result, filename, resultsz);
      g_free(filename);
    }
    gtk_widget_destroy(dlg);
  } else if (dlgtype == WEBVIEW_DIALOG_TYPE_ALERT) {
    GtkMessageType type = GTK_MESSAGE_OTHER;
    switch (flags & WEBVIEW_DIALOG_FLAG_ALERT_MASK) {
    case WEBVIEW_DIALOG_FLAG_INFO:
      type = GTK_MESSAGE_INFO;
      break;
    case WEBVIEW_DIALOG_FLAG_WARNING:
      type = GTK_MESSAGE_WARNING;
      break;
    case WEBVIEW_DIALOG_FLAG_ERROR:
      type = GTK_MESSAGE_ERROR;
      break;
    }
    dlg = gtk_message_dialog_new(GTK_WINDOW(w->priv.window), GTK_DIALOG_MODAL,
                                 type, GTK_BUTTONS_OK, "%s", title);
    gtk_message_dialog_format_secondary_text(GTK_MESSAGE_DIALOG(dlg), "%s",
                                             arg);
    gtk_dialog_run(GTK_DIALOG(dlg));
    gtk_widget_destroy(dlg);
  }
}

static void webview_eval_finished(GObject *object, GAsyncResult *result,
                                  gpointer userdata) {
  (void)object;
  (void)result;
  struct webview *w = (struct webview *)userdata;
  w->priv.js_busy = 0;
}

WEBVIEW_API int webview_eval(struct webview *w, const char *js) {
  while (w->priv.ready == 0) {
    g_main_context_iteration(NULL, TRUE);
  }
  w->priv.js_busy = 1;
  webkit_web_view_run_javascript(WEBKIT_WEB_VIEW(w->priv.webview), js, NULL,
                                 webview_eval_finished, w);
  while (w->priv.js_busy) {
    g_main_context_iteration(NULL, TRUE);
  }
  return 0;
}

static gboolean webview_dispatch_wrapper(gpointer userdata) {
  struct webview *w = (struct webview *)userdata;
  for (;;) {
    struct webview_dispatch_arg *arg =
        (struct webview_dispatch_arg *)g_async_queue_try_pop(w->priv.queue);
    if (arg == NULL) {
      break;
    }
    (arg->fn)(w, arg->arg);
    g_free(arg);
  }
  return FALSE;
}

WEBVIEW_API void webview_dispatch(struct webview *w, webview_dispatch_fn fn,
                                  void *arg) {
  struct webview_dispatch_arg *context =
      (struct webview_dispatch_arg *)g_new(struct webview_dispatch_arg, 1);
  context->w = w;
  context->arg = arg;
  context->fn = fn;
  g_async_queue_lock(w->priv.queue);
  g_async_queue_push_unlocked(w->priv.queue, context);
  if (g_async_queue_length_unlocked(w->priv.queue) == 1) {
    gdk_threads_add_idle(webview_dispatch_wrapper, w);
  }
  g_async_queue_unlock(w->priv.queue);
}

WEBVIEW_API void webview_terminate(struct webview *w) {
  w->priv.should_exit = 1;
}

WEBVIEW_API void webview_exit(struct webview *w) { (void)w; }
WEBVIEW_API void webview_print_log(const char *s) {
  fprintf(stderr, "%s\n", s);
}

#endif /* WEBVIEW_GTK */

#if defined(WEBVIEW_WINAPI)

#pragma comment(lib, "user32.lib")
#pragma comment(lib, "ole32.lib")
#pragma comment(lib, "oleaut32.lib")

#define WM_WEBVIEW_DISPATCH (WM_APP + 1)


typedef struct {
  IOleInPlaceFrame frame;
  HWND window;
} _IOleInPlaceFrameEx;

typedef struct {
  IOleInPlaceSite inplace;
  _IOleInPlaceFrameEx frame;
} _IOleInPlaceSiteEx;

typedef struct {
  IDocHostUIHandler ui;
} _IDocHostUIHandlerEx;

typedef struct {
  IOleClientSite client;
  _IOleInPlaceSiteEx inplace;
  _IDocHostUIHandlerEx ui;
  IDispatch external;
} _IOleClientSiteEx;

#ifdef __cplusplus
#define iid_ref(x) &(x)
#define iid_unref(x) *(x)
#else
#define iid_ref(x) (x)
#define iid_unref(x) (x)
#endif

static inline WCHAR *webview_to_utf16(const char *s) {
  DWORD size = MultiByteToWideChar(CP_UTF8, 0, s, -1, 0, 0);
  WCHAR *ws = (WCHAR *)GlobalAlloc(GMEM_FIXED, sizeof(WCHAR) * size);
  if (ws == NULL) {
    return NULL;
  }
  MultiByteToWideChar(CP_UTF8, 0, s, -1, ws, size);
  return ws;
}

static inline char *webview_from_utf16(WCHAR *ws) {
  int n = WideCharToMultiByte(CP_UTF8, 0, ws, -1, NULL, 0, NULL, NULL);
  char *s = (char *)GlobalAlloc(GMEM_FIXED, n);
  if (s == NULL) {
    return NULL;
  }
  WideCharToMultiByte(CP_UTF8, 0, ws, -1, s, n, NULL, NULL);
  return s;
}

static int iid_eq(REFIID a, const IID *b) {
  return memcmp((const void *)iid_ref(a), (const void *)b, sizeof(GUID)) == 0;
}

static HRESULT STDMETHODCALLTYPE JS_QueryInterface(IDispatch FAR *This,
                                                   REFIID riid,
                                                   LPVOID FAR *ppvObj) {
  if (iid_eq(riid, &IID_IDispatch)) {
    *ppvObj = This;
    return S_OK;
  }
  *ppvObj = 0;
  return E_NOINTERFACE;
}
static ULONG STDMETHODCALLTYPE JS_AddRef(IDispatch FAR *This) { return 1; }
static ULONG STDMETHODCALLTYPE JS_Release(IDispatch FAR *This) { return 1; }
static HRESULT STDMETHODCALLTYPE JS_GetTypeInfoCount(IDispatch FAR *This,
                                                     UINT *pctinfo) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE JS_GetTypeInfo(IDispatch FAR *This,
                                                UINT iTInfo, LCID lcid,
                                                ITypeInfo **ppTInfo) {
  return S_OK;
}
#define WEBVIEW_JS_INVOKE_ID 0x1000
static HRESULT STDMETHODCALLTYPE JS_GetIDsOfNames(IDispatch FAR *This,
                                                  REFIID riid,
                                                  LPOLESTR *rgszNames,
                                                  UINT cNames, LCID lcid,
                                                  DISPID *rgDispId) {
  if (cNames != 1) {
    return S_FALSE;
  }
  if (wcscmp(rgszNames[0], L"invoke") == 0) {
    rgDispId[0] = WEBVIEW_JS_INVOKE_ID;
    return S_OK;
  }
  return S_FALSE;
}

static HRESULT STDMETHODCALLTYPE
JS_Invoke(IDispatch FAR *This, DISPID dispIdMember, REFIID riid, LCID lcid,
          WORD wFlags, DISPPARAMS *pDispParams, VARIANT *pVarResult,
          EXCEPINFO *pExcepInfo, UINT *puArgErr) {
  size_t offset = (size_t) & ((_IOleClientSiteEx *)NULL)->external;
  _IOleClientSiteEx *ex = (_IOleClientSiteEx *)((char *)(This)-offset);
  struct webview *w = (struct webview *)GetWindowLongPtr(
      ex->inplace.frame.window, GWLP_USERDATA);
  if (pDispParams->cArgs == 1 && pDispParams->rgvarg[0].vt == VT_BSTR) {
    BSTR bstr = pDispParams->rgvarg[0].bstrVal;
    char *s = webview_from_utf16(bstr);
    if (s != NULL) {
      if (dispIdMember == WEBVIEW_JS_INVOKE_ID) {
        if (w->external_invoke_cb != NULL) {
          w->external_invoke_cb(w, s);
        }
      } else {
        return S_FALSE;
      }
      GlobalFree(s);
    }
  }
  return S_OK;
}

static IDispatchVtbl ExternalDispatchTable = {
    JS_QueryInterface, JS_AddRef,        JS_Release, JS_GetTypeInfoCount,
    JS_GetTypeInfo,    JS_GetIDsOfNames, JS_Invoke};

static ULONG STDMETHODCALLTYPE Site_AddRef(IOleClientSite FAR *This) {
  return 1;
}
static ULONG STDMETHODCALLTYPE Site_Release(IOleClientSite FAR *This) {
  return 1;
}
static HRESULT STDMETHODCALLTYPE Site_SaveObject(IOleClientSite FAR *This) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Site_GetMoniker(IOleClientSite FAR *This,
                                                 DWORD dwAssign,
                                                 DWORD dwWhichMoniker,
                                                 IMoniker **ppmk) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE
Site_GetContainer(IOleClientSite FAR *This, LPOLECONTAINER FAR *ppContainer) {
  *ppContainer = 0;
  return E_NOINTERFACE;
}
static HRESULT STDMETHODCALLTYPE Site_ShowObject(IOleClientSite FAR *This) {
  return NOERROR;
}
static HRESULT STDMETHODCALLTYPE Site_OnShowWindow(IOleClientSite FAR *This,
                                                   BOOL fShow) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE
Site_RequestNewObjectLayout(IOleClientSite FAR *This) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Site_QueryInterface(IOleClientSite FAR *This,
                                                     REFIID riid,
                                                     void **ppvObject) {
  if (iid_eq(riid, &IID_IUnknown) || iid_eq(riid, &IID_IOleClientSite)) {
    *ppvObject = &((_IOleClientSiteEx *)This)->client;
  } else if (iid_eq(riid, &IID_IOleInPlaceSite)) {
    *ppvObject = &((_IOleClientSiteEx *)This)->inplace;
  } else if (iid_eq(riid, &IID_IDocHostUIHandler)) {
    *ppvObject = &((_IOleClientSiteEx *)This)->ui;
  } else {
    *ppvObject = 0;
    return (E_NOINTERFACE);
  }
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE InPlace_QueryInterface(
    IOleInPlaceSite FAR *This, REFIID riid, LPVOID FAR *ppvObj) {
  return (Site_QueryInterface(
      (IOleClientSite *)((char *)This - sizeof(IOleClientSite)), riid, ppvObj));
}
static ULONG STDMETHODCALLTYPE InPlace_AddRef(IOleInPlaceSite FAR *This) {
  return 1;
}
static ULONG STDMETHODCALLTYPE InPlace_Release(IOleInPlaceSite FAR *This) {
  return 1;
}
static HRESULT STDMETHODCALLTYPE InPlace_GetWindow(IOleInPlaceSite FAR *This,
                                                   HWND FAR *lphwnd) {
  *lphwnd = ((_IOleInPlaceSiteEx FAR *)This)->frame.window;
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
InPlace_ContextSensitiveHelp(IOleInPlaceSite FAR *This, BOOL fEnterMode) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE
InPlace_CanInPlaceActivate(IOleInPlaceSite FAR *This) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
InPlace_OnInPlaceActivate(IOleInPlaceSite FAR *This) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
InPlace_OnUIActivate(IOleInPlaceSite FAR *This) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE InPlace_GetWindowContext(
    IOleInPlaceSite FAR *This, LPOLEINPLACEFRAME FAR *lplpFrame,
    LPOLEINPLACEUIWINDOW FAR *lplpDoc, LPRECT lprcPosRect, LPRECT lprcClipRect,
    LPOLEINPLACEFRAMEINFO lpFrameInfo) {
  *lplpFrame = (LPOLEINPLACEFRAME) & ((_IOleInPlaceSiteEx *)This)->frame;
  *lplpDoc = 0;
  lpFrameInfo->fMDIApp = FALSE;
  lpFrameInfo->hwndFrame = ((_IOleInPlaceFrameEx *)*lplpFrame)->window;
  lpFrameInfo->haccel = 0;
  lpFrameInfo->cAccelEntries = 0;
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE InPlace_Scroll(IOleInPlaceSite FAR *This,
                                                SIZE scrollExtent) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE
InPlace_OnUIDeactivate(IOleInPlaceSite FAR *This, BOOL fUndoable) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
InPlace_OnInPlaceDeactivate(IOleInPlaceSite FAR *This) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
InPlace_DiscardUndoState(IOleInPlaceSite FAR *This) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE
InPlace_DeactivateAndUndo(IOleInPlaceSite FAR *This) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE
InPlace_OnPosRectChange(IOleInPlaceSite FAR *This, LPCRECT lprcPosRect) {
  IOleObject *browserObject;
  IOleInPlaceObject *inplace;
  browserObject = *((IOleObject **)((char *)This - sizeof(IOleObject *) -
                                    sizeof(IOleClientSite)));
  if (!browserObject->lpVtbl->QueryInterface(browserObject,
                                             iid_unref(&IID_IOleInPlaceObject),
                                             (void **)&inplace)) {
    inplace->lpVtbl->SetObjectRects(inplace, lprcPosRect, lprcPosRect);
    inplace->lpVtbl->Release(inplace);
  }
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE Frame_QueryInterface(
    IOleInPlaceFrame FAR *This, REFIID riid, LPVOID FAR *ppvObj) {
  return E_NOTIMPL;
}
static ULONG STDMETHODCALLTYPE Frame_AddRef(IOleInPlaceFrame FAR *This) {
  return 1;
}
static ULONG STDMETHODCALLTYPE Frame_Release(IOleInPlaceFrame FAR *This) {
  return 1;
}
static HRESULT STDMETHODCALLTYPE Frame_GetWindow(IOleInPlaceFrame FAR *This,
                                                 HWND FAR *lphwnd) {
  *lphwnd = ((_IOleInPlaceFrameEx *)This)->window;
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
Frame_ContextSensitiveHelp(IOleInPlaceFrame FAR *This, BOOL fEnterMode) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Frame_GetBorder(IOleInPlaceFrame FAR *This,
                                                 LPRECT lprectBorder) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Frame_RequestBorderSpace(
    IOleInPlaceFrame FAR *This, LPCBORDERWIDTHS pborderwidths) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Frame_SetBorderSpace(
    IOleInPlaceFrame FAR *This, LPCBORDERWIDTHS pborderwidths) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Frame_SetActiveObject(
    IOleInPlaceFrame FAR *This, IOleInPlaceActiveObject *pActiveObject,
    LPCOLESTR pszObjName) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
Frame_InsertMenus(IOleInPlaceFrame FAR *This, HMENU hmenuShared,
                  LPOLEMENUGROUPWIDTHS lpMenuWidths) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Frame_SetMenu(IOleInPlaceFrame FAR *This,
                                               HMENU hmenuShared,
                                               HOLEMENU holemenu,
                                               HWND hwndActiveObject) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE Frame_RemoveMenus(IOleInPlaceFrame FAR *This,
                                                   HMENU hmenuShared) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE Frame_SetStatusText(IOleInPlaceFrame FAR *This,
                                                     LPCOLESTR pszStatusText) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
Frame_EnableModeless(IOleInPlaceFrame FAR *This, BOOL fEnable) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
Frame_TranslateAccelerator(IOleInPlaceFrame FAR *This, LPMSG lpmsg, WORD wID) {
  return E_NOTIMPL;
}
static HRESULT STDMETHODCALLTYPE UI_QueryInterface(IDocHostUIHandler FAR *This,
                                                   REFIID riid,
                                                   LPVOID FAR *ppvObj) {
  return (Site_QueryInterface((IOleClientSite *)((char *)This -
                                                 sizeof(IOleClientSite) -
                                                 sizeof(_IOleInPlaceSiteEx)),
                              riid, ppvObj));
}
static ULONG STDMETHODCALLTYPE UI_AddRef(IDocHostUIHandler FAR *This) {
  return 1;
}
static ULONG STDMETHODCALLTYPE UI_Release(IDocHostUIHandler FAR *This) {
  return 1;
}
static HRESULT STDMETHODCALLTYPE UI_ShowContextMenu(
    IDocHostUIHandler FAR *This, DWORD dwID, POINT __RPC_FAR *ppt,
    IUnknown __RPC_FAR *pcmdtReserved, IDispatch __RPC_FAR *pdispReserved) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
UI_GetHostInfo(IDocHostUIHandler FAR *This, DOCHOSTUIINFO __RPC_FAR *pInfo) {
  pInfo->cbSize = sizeof(DOCHOSTUIINFO);
  pInfo->dwFlags = DOCHOSTUIFLAG_NO3DBORDER | DOCHOSTUIFLAG_DPI_AWARE;
  pInfo->dwDoubleClick = DOCHOSTUIDBLCLK_DEFAULT;
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE UI_ShowUI(
    IDocHostUIHandler FAR *This, DWORD dwID,
    IOleInPlaceActiveObject __RPC_FAR *pActiveObject,
    IOleCommandTarget __RPC_FAR *pCommandTarget,
    IOleInPlaceFrame __RPC_FAR *pFrame, IOleInPlaceUIWindow __RPC_FAR *pDoc) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE UI_HideUI(IDocHostUIHandler FAR *This) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE UI_UpdateUI(IDocHostUIHandler FAR *This) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE UI_EnableModeless(IDocHostUIHandler FAR *This,
                                                   BOOL fEnable) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
UI_OnDocWindowActivate(IDocHostUIHandler FAR *This, BOOL fActivate) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
UI_OnFrameWindowActivate(IDocHostUIHandler FAR *This, BOOL fActivate) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
UI_ResizeBorder(IDocHostUIHandler FAR *This, LPCRECT prcBorder,
                IOleInPlaceUIWindow __RPC_FAR *pUIWindow, BOOL fRameWindow) {
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE
UI_TranslateAccelerator(IDocHostUIHandler FAR *This, LPMSG lpMsg,
                        const GUID __RPC_FAR *pguidCmdGroup, DWORD nCmdID) {
  return S_FALSE;
}
static HRESULT STDMETHODCALLTYPE UI_GetOptionKeyPath(
    IDocHostUIHandler FAR *This, LPOLESTR __RPC_FAR *pchKey, DWORD dw) {
  return S_FALSE;
}
static HRESULT STDMETHODCALLTYPE UI_GetDropTarget(
    IDocHostUIHandler FAR *This, IDropTarget __RPC_FAR *pDropTarget,
    IDropTarget __RPC_FAR *__RPC_FAR *ppDropTarget) {
  return S_FALSE;
}
static HRESULT STDMETHODCALLTYPE UI_GetExternal(
    IDocHostUIHandler FAR *This, IDispatch __RPC_FAR *__RPC_FAR *ppDispatch) {
  *ppDispatch = (IDispatch *)(This + 1);
  return S_OK;
}
static HRESULT STDMETHODCALLTYPE UI_TranslateUrl(
    IDocHostUIHandler FAR *This, DWORD dwTranslate, OLECHAR __RPC_FAR *pchURLIn,
    OLECHAR __RPC_FAR *__RPC_FAR *ppchURLOut) {
  *ppchURLOut = 0;
  return S_FALSE;
}
static HRESULT STDMETHODCALLTYPE
UI_FilterDataObject(IDocHostUIHandler FAR *This, IDataObject __RPC_FAR *pDO,
                    IDataObject __RPC_FAR *__RPC_FAR *ppDORet) {
  *ppDORet = 0;
  return S_FALSE;
}

static const TCHAR *classname = "WebView";
static const SAFEARRAYBOUND ArrayBound = {1, 0};

static IOleClientSiteVtbl MyIOleClientSiteTable = {
    Site_QueryInterface, Site_AddRef,       Site_Release,
    Site_SaveObject,     Site_GetMoniker,   Site_GetContainer,
    Site_ShowObject,     Site_OnShowWindow, Site_RequestNewObjectLayout};
static IOleInPlaceSiteVtbl MyIOleInPlaceSiteTable = {
    InPlace_QueryInterface,
    InPlace_AddRef,
    InPlace_Release,
    InPlace_GetWindow,
    InPlace_ContextSensitiveHelp,
    InPlace_CanInPlaceActivate,
    InPlace_OnInPlaceActivate,
    InPlace_OnUIActivate,
    InPlace_GetWindowContext,
    InPlace_Scroll,
    InPlace_OnUIDeactivate,
    InPlace_OnInPlaceDeactivate,
    InPlace_DiscardUndoState,
    InPlace_DeactivateAndUndo,
    InPlace_OnPosRectChange};

static IOleInPlaceFrameVtbl MyIOleInPlaceFrameTable = {
    Frame_QueryInterface,
    Frame_AddRef,
    Frame_Release,
    Frame_GetWindow,
    Frame_ContextSensitiveHelp,
    Frame_GetBorder,
    Frame_RequestBorderSpace,
    Frame_SetBorderSpace,
    Frame_SetActiveObject,
    Frame_InsertMenus,
    Frame_SetMenu,
    Frame_RemoveMenus,
    Frame_SetStatusText,
    Frame_EnableModeless,
    Frame_TranslateAccelerator};

static IDocHostUIHandlerVtbl MyIDocHostUIHandlerTable = {
    UI_QueryInterface,
    UI_AddRef,
    UI_Release,
    UI_ShowContextMenu,
    UI_GetHostInfo,
    UI_ShowUI,
    UI_HideUI,
    UI_UpdateUI,
    UI_EnableModeless,
    UI_OnDocWindowActivate,
    UI_OnFrameWindowActivate,
    UI_ResizeBorder,
    UI_TranslateAccelerator,
    UI_GetOptionKeyPath,
    UI_GetDropTarget,
    UI_GetExternal,
    UI_TranslateUrl,
    UI_FilterDataObject};

static void UnEmbedBrowserObject(struct webview *w) {
  if (w->priv.browser != NULL) {
    (*w->priv.browser)->lpVtbl->Close(*w->priv.browser, OLECLOSE_NOSAVE);
    (*w->priv.browser)->lpVtbl->Release(*w->priv.browser);
    GlobalFree(w->priv.browser);
    w->priv.browser = NULL;
  }
}

static int EmbedBrowserObject(struct webview *w) {
  RECT rect;
  IWebBrowser2 *webBrowser2 = NULL;
  LPCLASSFACTORY pClassFactory = NULL;
  _IOleClientSiteEx *_iOleClientSiteEx = NULL;
  IOleObject **browser = (IOleObject **)GlobalAlloc(
      GMEM_FIXED, sizeof(IOleObject *) + sizeof(_IOleClientSiteEx));
  if (browser == NULL) {
    goto error;
  }
  w->priv.browser = browser;

  _iOleClientSiteEx = (_IOleClientSiteEx *)(browser + 1);
  _iOleClientSiteEx->client.lpVtbl = &MyIOleClientSiteTable;
  _iOleClientSiteEx->inplace.inplace.lpVtbl = &MyIOleInPlaceSiteTable;
  _iOleClientSiteEx->inplace.frame.frame.lpVtbl = &MyIOleInPlaceFrameTable;
  _iOleClientSiteEx->inplace.frame.window = w->priv.hwnd;
  _iOleClientSiteEx->ui.ui.lpVtbl = &MyIDocHostUIHandlerTable;
  _iOleClientSiteEx->external.lpVtbl = &ExternalDispatchTable;

  if (CoGetClassObject(iid_unref(&CLSID_WebBrowser),
                       CLSCTX_INPROC_SERVER | CLSCTX_INPROC_HANDLER, NULL,
                       iid_unref(&IID_IClassFactory),
                       (void **)&pClassFactory) != S_OK) {
    goto error;
  }

  if (pClassFactory == NULL) {
    goto error;
  }

  if (pClassFactory->lpVtbl->CreateInstance(pClassFactory, 0,
                                            iid_unref(&IID_IOleObject),
                                            (void **)browser) != S_OK) {
    goto error;
  }
  pClassFactory->lpVtbl->Release(pClassFactory);
  if ((*browser)->lpVtbl->SetClientSite(
          *browser, (IOleClientSite *)_iOleClientSiteEx) != S_OK) {
    goto error;
  }
  (*browser)->lpVtbl->SetHostNames(*browser, L"My Host Name", 0);

  if (OleSetContainedObject((struct IUnknown *)(*browser), TRUE) != S_OK) {
    goto error;
  }
  GetClientRect(w->priv.hwnd, &rect);
  if ((*browser)->lpVtbl->DoVerb((*browser), OLEIVERB_SHOW, NULL,
                                 (IOleClientSite *)_iOleClientSiteEx, -1,
                                 w->priv.hwnd, &rect) != S_OK) {
    goto error;
  }
  if ((*browser)->lpVtbl->QueryInterface((*browser),
                                         iid_unref(&IID_IWebBrowser2),
                                         (void **)&webBrowser2) != S_OK) {
    goto error;
  }

  webBrowser2->lpVtbl->put_Left(webBrowser2, 0);
  webBrowser2->lpVtbl->put_Top(webBrowser2, 0);
  webBrowser2->lpVtbl->put_Width(webBrowser2, rect.right);
  webBrowser2->lpVtbl->put_Height(webBrowser2, rect.bottom);
  webBrowser2->lpVtbl->Release(webBrowser2);

  return 0;
error:
  UnEmbedBrowserObject(w);
  if (pClassFactory != NULL) {
    pClassFactory->lpVtbl->Release(pClassFactory);
  }
  if (browser != NULL) {
    GlobalFree(browser);
  }
  return -1;
}

#define WEBVIEW_DATA_URL_PREFIX "data:text/html,"
static int DisplayHTMLPage(struct webview *w) {
  IWebBrowser2 *webBrowser2;
  VARIANT myURL;
  LPDISPATCH lpDispatch;
  IHTMLDocument2 *htmlDoc2;
  BSTR bstr;
  IOleObject *browserObject;
  SAFEARRAY *sfArray;
  VARIANT *pVar;
  browserObject = *w->priv.browser;
  int isDataURL = 0;
  const char *webview_url = webview_check_url(w->url);
  if (!browserObject->lpVtbl->QueryInterface(
          browserObject, iid_unref(&IID_IWebBrowser2), (void **)&webBrowser2)) {
    LPCSTR webPageName;
    isDataURL = (strncmp(webview_url, WEBVIEW_DATA_URL_PREFIX,
                         strlen(WEBVIEW_DATA_URL_PREFIX)) == 0);
    if (isDataURL) {
      webPageName = "about:blank";
    } else {
      webPageName = (LPCSTR)webview_url;
    }
    VariantInit(&myURL);
    myURL.vt = VT_BSTR;
#ifndef UNICODE
    {
      wchar_t *buffer = webview_to_utf16(webPageName);
      if (buffer == NULL) {
        goto badalloc;
      }
      myURL.bstrVal = SysAllocString(buffer);
      GlobalFree(buffer);
    }
#else
    myURL.bstrVal = SysAllocString(webPageName);
#endif
    if (!myURL.bstrVal) {
    badalloc:
      webBrowser2->lpVtbl->Release(webBrowser2);
      return (-6);
    }

	webBrowser2->lpVtbl->put_Silent(webBrowser2, w->debug ? FALSE : TRUE);

    webBrowser2->lpVtbl->Navigate2(webBrowser2, &myURL, 0, 0, 0, 0);
    VariantClear(&myURL);
    if (!isDataURL) {
      return 0;
    }

    char *url = (char *)calloc(1, strlen(webview_url) + 1);
    char *q = url;
    for (const char *p = webview_url + strlen(WEBVIEW_DATA_URL_PREFIX); *q = *p;
         p++, q++) {
      if (*q == '%' && *(p + 1) && *(p + 2)) {
        sscanf(p + 1, "%02x", q);
        p = p + 2;
      }
    }

    if (webBrowser2->lpVtbl->get_Document(webBrowser2, &lpDispatch) == S_OK) {
      if (lpDispatch->lpVtbl->QueryInterface(lpDispatch,
                                             iid_unref(&IID_IHTMLDocument2),
                                             (void **)&htmlDoc2) == S_OK) {
        if ((sfArray = SafeArrayCreate(VT_VARIANT, 1,
                                       (SAFEARRAYBOUND *)&ArrayBound))) {
          if (!SafeArrayAccessData(sfArray, (void **)&pVar)) {
            pVar->vt = VT_BSTR;
#ifndef UNICODE
            {
              wchar_t *buffer = webview_to_utf16(url);
              if (buffer == NULL) {
                goto release;
              }
              bstr = SysAllocString(buffer);
              GlobalFree(buffer);
            }
#else
            bstr = SysAllocString(string);
#endif
            if ((pVar->bstrVal = bstr)) {
              htmlDoc2->lpVtbl->write(htmlDoc2, sfArray);
              htmlDoc2->lpVtbl->close(htmlDoc2);
            }
          }
          SafeArrayDestroy(sfArray);
        }
      release:
        free(url);
        htmlDoc2->lpVtbl->Release(htmlDoc2);
      }
      lpDispatch->lpVtbl->Release(lpDispatch);
    }
    webBrowser2->lpVtbl->Release(webBrowser2);
    return (0);
  }
  return (-5);
}

static LRESULT CALLBACK wndproc(HWND hwnd, UINT uMsg, WPARAM wParam,
                                LPARAM lParam) {
  struct webview *w = (struct webview *)GetWindowLongPtr(hwnd, GWLP_USERDATA);
  switch (uMsg) {
  case WM_CREATE:
    w = (struct webview *)((CREATESTRUCT *)lParam)->lpCreateParams;
    w->priv.hwnd = hwnd;
    return EmbedBrowserObject(w);
  case WM_DESTROY:
    UnEmbedBrowserObject(w);
    PostQuitMessage(0);
    return TRUE;
  case WM_SIZE: {
    IWebBrowser2 *webBrowser2;
    IOleObject *browser = *w->priv.browser;
    if (browser->lpVtbl->QueryInterface(browser, iid_unref(&IID_IWebBrowser2),
                                        (void **)&webBrowser2) == S_OK) {
      RECT rect;
      GetClientRect(hwnd, &rect);
      webBrowser2->lpVtbl->put_Width(webBrowser2, rect.right);
      webBrowser2->lpVtbl->put_Height(webBrowser2, rect.bottom);
    }
    return TRUE;
  }
  case WM_WEBVIEW_DISPATCH: {
    webview_dispatch_fn f = (webview_dispatch_fn)wParam;
    void *arg = (void *)lParam;
    (*f)(w, arg);
    return TRUE;
  }
  }
  return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

#define WEBVIEW_KEY_FEATURE_BROWSER_EMULATION                                  \
  "Software\\Microsoft\\Internet "                                             \
  "Explorer\\Main\\FeatureControl\\FEATURE_BROWSER_EMULATION"

static int webview_fix_ie_compat_mode() {
  HKEY hKey;
  DWORD ie_version = 11000;
  TCHAR appname[MAX_PATH + 1];
  TCHAR *p;
  if (GetModuleFileName(NULL, appname, MAX_PATH + 1) == 0) {
    return -1;
  }
  for (p = &appname[strlen(appname) - 1]; p != appname && *p != '\\'; p--) {
  }
  p++;
  if (RegCreateKey(HKEY_CURRENT_USER, WEBVIEW_KEY_FEATURE_BROWSER_EMULATION,
                   &hKey) != ERROR_SUCCESS) {
    return -1;
  }
  if (RegSetValueEx(hKey, p, 0, REG_DWORD, (BYTE *)&ie_version,
                    sizeof(ie_version)) != ERROR_SUCCESS) {
    RegCloseKey(hKey);
    return -1;
  }
  RegCloseKey(hKey);
  return 0;
}

WEBVIEW_API int webview_init(struct webview *w) {
  WNDCLASSEX wc;
  HINSTANCE hInstance;
  DWORD style;
  RECT clientRect;
  RECT rect;


  if (webview_fix_ie_compat_mode() < 0) {
    return -1;
  }

  hInstance = GetModuleHandle(NULL);
  if (hInstance == NULL) {
    return -1;
  }
  if (OleInitialize(NULL) != S_OK) {
    return -1;
  }

#ifdef DPI_AWARENESS_CONTEXT_SYSTEM_AWARE //win8.1+
  SetProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_SYSTEM_AWARE);
#endif

  ZeroMemory(&wc, sizeof(WNDCLASSEX));
  wc.cbSize = sizeof(WNDCLASSEX);
  wc.hInstance = hInstance;
  wc.lpfnWndProc = wndproc;
  wc.lpszClassName = classname;
  RegisterClassEx(&wc);

  style = WS_OVERLAPPEDWINDOW;
  if (!w->resizable) {
    style = WS_OVERLAPPED | WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU;
  }

#ifndef GetDpiForSystem //win8.1+
#define GetDpiForSystem() (96.0f)
#endif

  double scale = GetDpiForSystem() / 96.0f;
  rect.left = 0;
  rect.top = 0;
  rect.right = w->width * scale;
  rect.bottom = w->height * scale;
  AdjustWindowRect(&rect, WS_OVERLAPPEDWINDOW, 0);

  GetClientRect(GetDesktopWindow(), &clientRect);
  int left = (clientRect.right / 2) - ((rect.right - rect.left) / 2);
  int top = (clientRect.bottom / 2) - ((rect.bottom - rect.top) / 2);
  rect.right = rect.right - rect.left + left;
  rect.left = left;
  rect.bottom = rect.bottom - rect.top + top;
  rect.top = top;

  w->priv.hwnd =
      CreateWindowEx(0, classname, w->title, style, rect.left, rect.top,
                     rect.right - rect.left, rect.bottom - rect.top,
                     HWND_DESKTOP, NULL, hInstance, (void *)w);
  if (w->priv.hwnd == 0) {
    OleUninitialize();
    return -1;
  }

  SetWindowLongPtr(w->priv.hwnd, GWLP_USERDATA, (LONG_PTR)w);

  DisplayHTMLPage(w);

  SetWindowText(w->priv.hwnd, w->title);
  ShowWindow(w->priv.hwnd, SW_SHOWDEFAULT);
  UpdateWindow(w->priv.hwnd);
  SetFocus(w->priv.hwnd);

  return 0;
}

WEBVIEW_API int webview_loop(struct webview *w, int blocking) {
  MSG msg;
  if (blocking) {
    GetMessage(&msg, 0, 0, 0);
  } else {
    PeekMessage(&msg, 0, 0, 0, PM_REMOVE);
  }
  switch (msg.message) {
  case WM_QUIT:
    return -1;
  case WM_COMMAND:
  case WM_KEYDOWN:
  case WM_KEYUP: {
    HRESULT r = S_OK;
    IWebBrowser2 *webBrowser2;
    IOleObject *browser = *w->priv.browser;
    if (browser->lpVtbl->QueryInterface(browser, iid_unref(&IID_IWebBrowser2),
                                        (void **)&webBrowser2) == S_OK) {
      IOleInPlaceActiveObject *pIOIPAO;
      if (browser->lpVtbl->QueryInterface(
              browser, iid_unref(&IID_IOleInPlaceActiveObject),
              (void **)&pIOIPAO) == S_OK) {
        r = pIOIPAO->lpVtbl->TranslateAccelerator(pIOIPAO, &msg);
        pIOIPAO->lpVtbl->Release(pIOIPAO);
      }
      webBrowser2->lpVtbl->Release(webBrowser2);
    }
    if (r != S_FALSE) {
      break;
    }
  }
  default:
    TranslateMessage(&msg);
    DispatchMessage(&msg);
  }
  return 0;
}

WEBVIEW_API int webview_eval(struct webview *w, const char *js) {
  IWebBrowser2 *webBrowser2;
  IHTMLDocument2 *htmlDoc2;
  IDispatch *docDispatch;
  IDispatch *scriptDispatch;
  if ((*w->priv.browser)
          ->lpVtbl->QueryInterface((*w->priv.browser),
                                   iid_unref(&IID_IWebBrowser2),
                                   (void **)&webBrowser2) != S_OK) {
    return -1;
  }

  if (webBrowser2->lpVtbl->get_Document(webBrowser2, &docDispatch) != S_OK) {
    return -1;
  }
  if (docDispatch->lpVtbl->QueryInterface(docDispatch,
                                          iid_unref(&IID_IHTMLDocument2),
                                          (void **)&htmlDoc2) != S_OK) {
    return -1;
  }
  if (htmlDoc2->lpVtbl->get_Script(htmlDoc2, &scriptDispatch) != S_OK) {
    return -1;
  }
  DISPID dispid;
  BSTR evalStr = SysAllocString(L"eval");
  if (scriptDispatch->lpVtbl->GetIDsOfNames(
          scriptDispatch, iid_unref(&IID_NULL), &evalStr, 1,
          LOCALE_SYSTEM_DEFAULT, &dispid) != S_OK) {
    SysFreeString(evalStr);
    return -1;
  }
  SysFreeString(evalStr);

  DISPPARAMS params;
  VARIANT arg;
  VARIANT result;
  EXCEPINFO excepInfo;
  UINT nArgErr = (UINT)-1;
  params.cArgs = 1;
  params.cNamedArgs = 0;
  params.rgvarg = &arg;
  arg.vt = VT_BSTR;
  static const char *prologue = "(function(){";
  static const char *epilogue = ";})();";
  int n = strlen(prologue) + strlen(epilogue) + strlen(js) + 1;
  char *eval = (char *)malloc(n);
  snprintf(eval, n, "%s%s%s", prologue, js, epilogue);
  wchar_t *buf = webview_to_utf16(eval);
  if (buf == NULL) {
    return -1;
  }
  arg.bstrVal = SysAllocString(buf);
  if (scriptDispatch->lpVtbl->Invoke(
          scriptDispatch, dispid, iid_unref(&IID_NULL), 0, DISPATCH_METHOD,
          &params, &result, &excepInfo, &nArgErr) != S_OK) {
    return -1;
  }
  SysFreeString(arg.bstrVal);
  free(eval);
  scriptDispatch->lpVtbl->Release(scriptDispatch);
  htmlDoc2->lpVtbl->Release(htmlDoc2);
  docDispatch->lpVtbl->Release(docDispatch);
  return 0;
}

WEBVIEW_API void webview_dispatch(struct webview *w, webview_dispatch_fn fn,
                                  void *arg) {
  PostMessageW(w->priv.hwnd, WM_WEBVIEW_DISPATCH, (WPARAM)fn, (LPARAM)arg);
}

WEBVIEW_API void webview_set_title(struct webview *w, const char *title) {
  SetWindowText(w->priv.hwnd, title);
}

WEBVIEW_API void webview_set_fullscreen(struct webview *w, int fullscreen) {
  if (w->priv.is_fullscreen == !!fullscreen) {
    return;
  }
  if (w->priv.is_fullscreen == 0) {
    w->priv.saved_style = GetWindowLong(w->priv.hwnd, GWL_STYLE);
    w->priv.saved_ex_style = GetWindowLong(w->priv.hwnd, GWL_EXSTYLE);
    GetWindowRect(w->priv.hwnd, &w->priv.saved_rect);
  }
  w->priv.is_fullscreen = !!fullscreen;
  if (fullscreen) {
    MONITORINFO monitor_info;
    SetWindowLong(w->priv.hwnd, GWL_STYLE,
                  w->priv.saved_style & ~(WS_CAPTION | WS_THICKFRAME));
    SetWindowLong(w->priv.hwnd, GWL_EXSTYLE,
                  w->priv.saved_ex_style &
                      ~(WS_EX_DLGMODALFRAME | WS_EX_WINDOWEDGE |
                        WS_EX_CLIENTEDGE | WS_EX_STATICEDGE));
    monitor_info.cbSize = sizeof(monitor_info);
    GetMonitorInfo(MonitorFromWindow(w->priv.hwnd, MONITOR_DEFAULTTONEAREST),
                   &monitor_info);
    RECT r;
    r.left = monitor_info.rcMonitor.left;
    r.top = monitor_info.rcMonitor.top;
    r.right = monitor_info.rcMonitor.right;
    r.bottom = monitor_info.rcMonitor.bottom;
    SetWindowPos(w->priv.hwnd, NULL, r.left, r.top, r.right - r.left,
                 r.bottom - r.top,
                 SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
  } else {
    SetWindowLong(w->priv.hwnd, GWL_STYLE, w->priv.saved_style);
    SetWindowLong(w->priv.hwnd, GWL_EXSTYLE, w->priv.saved_ex_style);
    SetWindowPos(w->priv.hwnd, NULL, w->priv.saved_rect.left,
                 w->priv.saved_rect.top,
                 w->priv.saved_rect.right - w->priv.saved_rect.left,
                 w->priv.saved_rect.bottom - w->priv.saved_rect.top,
                 SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
  }
}

WEBVIEW_API void webview_set_color(struct webview *w, uint8_t r, uint8_t g,
                                   uint8_t b, uint8_t a) {
  HBRUSH brush = CreateSolidBrush(RGB(r, g, b));
  SetClassLongPtr(w->priv.hwnd, GCLP_HBRBACKGROUND, (LONG_PTR)brush);
}

/* These are missing parts from MinGW */
#ifndef __IFileDialog_INTERFACE_DEFINED__
#define __IFileDialog_INTERFACE_DEFINED__
enum _FILEOPENDIALOGOPTIONS {
  FOS_OVERWRITEPROMPT = 0x2,
  FOS_STRICTFILETYPES = 0x4,
  FOS_NOCHANGEDIR = 0x8,
  FOS_PICKFOLDERS = 0x20,
  FOS_FORCEFILESYSTEM = 0x40,
  FOS_ALLNONSTORAGEITEMS = 0x80,
  FOS_NOVALIDATE = 0x100,
  FOS_ALLOWMULTISELECT = 0x200,
  FOS_PATHMUSTEXIST = 0x800,
  FOS_FILEMUSTEXIST = 0x1000,
  FOS_CREATEPROMPT = 0x2000,
  FOS_SHAREAWARE = 0x4000,
  FOS_NOREADONLYRETURN = 0x8000,
  FOS_NOTESTFILECREATE = 0x10000,
  FOS_HIDEMRUPLACES = 0x20000,
  FOS_HIDEPINNEDPLACES = 0x40000,
  FOS_NODEREFERENCELINKS = 0x100000,
  FOS_DONTADDTORECENT = 0x2000000,
  FOS_FORCESHOWHIDDEN = 0x10000000,
  FOS_DEFAULTNOMINIMODE = 0x20000000,
  FOS_FORCEPREVIEWPANEON = 0x40000000
};
typedef DWORD FILEOPENDIALOGOPTIONS;
typedef enum FDAP { FDAP_BOTTOM = 0, FDAP_TOP = 1 } FDAP;
DEFINE_GUID(IID_IFileDialog, 0x42f85136, 0xdb7e, 0x439c, 0x85, 0xf1, 0xe4, 0x07,
            0x5d, 0x13, 0x5f, 0xc8);
typedef struct IFileDialogVtbl {
  BEGIN_INTERFACE
  HRESULT(STDMETHODCALLTYPE *QueryInterface)
  (IFileDialog *This, REFIID riid, void **ppvObject);
  ULONG(STDMETHODCALLTYPE *AddRef)(IFileDialog *This);
  ULONG(STDMETHODCALLTYPE *Release)(IFileDialog *This);
  HRESULT(STDMETHODCALLTYPE *Show)(IFileDialog *This, HWND hwndOwner);
  HRESULT(STDMETHODCALLTYPE *SetFileTypes)
  (IFileDialog *This, UINT cFileTypes, const COMDLG_FILTERSPEC *rgFilterSpec);
  HRESULT(STDMETHODCALLTYPE *SetFileTypeIndex)
  (IFileDialog *This, UINT iFileType);
  HRESULT(STDMETHODCALLTYPE *GetFileTypeIndex)
  (IFileDialog *This, UINT *piFileType);
  HRESULT(STDMETHODCALLTYPE *Advise)
  (IFileDialog *This, IFileDialogEvents *pfde, DWORD *pdwCookie);
  HRESULT(STDMETHODCALLTYPE *Unadvise)(IFileDialog *This, DWORD dwCookie);
  HRESULT(STDMETHODCALLTYPE *SetOptions)
  (IFileDialog *This, FILEOPENDIALOGOPTIONS fos);
  HRESULT(STDMETHODCALLTYPE *GetOptions)
  (IFileDialog *This, FILEOPENDIALOGOPTIONS *pfos);
  HRESULT(STDMETHODCALLTYPE *SetDefaultFolder)
  (IFileDialog *This, IShellItem *psi);
  HRESULT(STDMETHODCALLTYPE *SetFolder)(IFileDialog *This, IShellItem *psi);
  HRESULT(STDMETHODCALLTYPE *GetFolder)(IFileDialog *This, IShellItem **ppsi);
  HRESULT(STDMETHODCALLTYPE *GetCurrentSelection)
  (IFileDialog *This, IShellItem **ppsi);
  HRESULT(STDMETHODCALLTYPE *SetFileName)(IFileDialog *This, LPCWSTR pszName);
  HRESULT(STDMETHODCALLTYPE *GetFileName)(IFileDialog *This, LPWSTR *pszName);
  HRESULT(STDMETHODCALLTYPE *SetTitle)(IFileDialog *This, LPCWSTR pszTitle);
  HRESULT(STDMETHODCALLTYPE *SetOkButtonLabel)
  (IFileDialog *This, LPCWSTR pszText);
  HRESULT(STDMETHODCALLTYPE *SetFileNameLabel)
  (IFileDialog *This, LPCWSTR pszLabel);
  HRESULT(STDMETHODCALLTYPE *GetResult)(IFileDialog *This, IShellItem **ppsi);
  HRESULT(STDMETHODCALLTYPE *AddPlace)
  (IFileDialog *This, IShellItem *psi, FDAP fdap);
  HRESULT(STDMETHODCALLTYPE *SetDefaultExtension)
  (IFileDialog *This, LPCWSTR pszDefaultExtension);
  HRESULT(STDMETHODCALLTYPE *Close)(IFileDialog *This, HRESULT hr);
  HRESULT(STDMETHODCALLTYPE *SetClientGuid)(IFileDialog *This, REFGUID guid);
  HRESULT(STDMETHODCALLTYPE *ClearClientData)(IFileDialog *This);
  HRESULT(STDMETHODCALLTYPE *SetFilter)
  (IFileDialog *This, IShellItemFilter *pFilter);
  END_INTERFACE
} IFileDialogVtbl;
interface IFileDialog {
  CONST_VTBL IFileDialogVtbl *lpVtbl;
};
DEFINE_GUID(IID_IFileOpenDialog, 0xd57c7288, 0xd4ad, 0x4768, 0xbe, 0x02, 0x9d,
            0x96, 0x95, 0x32, 0xd9, 0x60);
DEFINE_GUID(IID_IFileSaveDialog, 0x84bccd23, 0x5fde, 0x4cdb, 0xae, 0xa4, 0xaf,
            0x64, 0xb8, 0x3d, 0x78, 0xab);
#endif

WEBVIEW_API void webview_dialog(struct webview *w,
                                enum webview_dialog_type dlgtype, int flags,
                                const char *title, const char *arg,
                                char *result, size_t resultsz) {
  if (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN ||
      dlgtype == WEBVIEW_DIALOG_TYPE_SAVE) {
    IFileDialog *dlg = NULL;
    IShellItem *res = NULL;
    WCHAR *ws = NULL;
    char *s = NULL;
    FILEOPENDIALOGOPTIONS opts, add_opts;
    if (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN) {
      if (CoCreateInstance(
              iid_unref(&CLSID_FileOpenDialog), NULL, CLSCTX_INPROC_SERVER,
              iid_unref(&IID_IFileOpenDialog), (void **)&dlg) != S_OK) {
        goto error_dlg;
      }
      if (flags & WEBVIEW_DIALOG_FLAG_DIRECTORY) {
        add_opts |= FOS_PICKFOLDERS;
      }
      add_opts |= FOS_NOCHANGEDIR | FOS_ALLNONSTORAGEITEMS | FOS_NOVALIDATE |
                  FOS_PATHMUSTEXIST | FOS_FILEMUSTEXIST | FOS_SHAREAWARE |
                  FOS_NOTESTFILECREATE | FOS_NODEREFERENCELINKS |
                  FOS_FORCESHOWHIDDEN | FOS_DEFAULTNOMINIMODE;
    } else {
      if (CoCreateInstance(
              iid_unref(&CLSID_FileSaveDialog), NULL, CLSCTX_INPROC_SERVER,
              iid_unref(&IID_IFileSaveDialog), (void **)&dlg) != S_OK) {
        goto error_dlg;
      }
      add_opts |= FOS_OVERWRITEPROMPT | FOS_NOCHANGEDIR |
                  FOS_ALLNONSTORAGEITEMS | FOS_NOVALIDATE | FOS_SHAREAWARE |
                  FOS_NOTESTFILECREATE | FOS_NODEREFERENCELINKS |
                  FOS_FORCESHOWHIDDEN | FOS_DEFAULTNOMINIMODE;
    }
    if (dlg->lpVtbl->GetOptions(dlg, &opts) != S_OK) {
      goto error_dlg;
    }
    opts &= ~FOS_NOREADONLYRETURN;
    opts |= add_opts;
    if (dlg->lpVtbl->SetOptions(dlg, opts) != S_OK) {
      goto error_dlg;
    }
    if (dlg->lpVtbl->Show(dlg, w->priv.hwnd) != S_OK) {
      goto error_dlg;
    }
    if (dlg->lpVtbl->GetResult(dlg, &res) != S_OK) {
      goto error_dlg;
    }
    if (res->lpVtbl->GetDisplayName(res, SIGDN_FILESYSPATH, &ws) != S_OK) {
      goto error_result;
    }
    s = webview_from_utf16(ws);
    strncpy(result, s, resultsz);
    result[resultsz - 1] = '\0';
    CoTaskMemFree(ws);
  error_result:
    res->lpVtbl->Release(res);
  error_dlg:
    dlg->lpVtbl->Release(dlg);
    return;
  } else if (dlgtype == WEBVIEW_DIALOG_TYPE_ALERT) {
#if 0
    /* MinGW often doesn't contain TaskDialog, we'll use MessageBox for now */
    WCHAR *wtitle = webview_to_utf16(title);
    WCHAR *warg = webview_to_utf16(arg);
    TaskDialog(w->priv.hwnd, NULL, NULL, wtitle, warg, 0, NULL, NULL);
    GlobalFree(warg);
    GlobalFree(wtitle);
#else
    UINT type = MB_OK;
    switch (flags & WEBVIEW_DIALOG_FLAG_ALERT_MASK) {
    case WEBVIEW_DIALOG_FLAG_INFO:
      type |= MB_ICONINFORMATION;
      break;
    case WEBVIEW_DIALOG_FLAG_WARNING:
      type |= MB_ICONWARNING;
      break;
    case WEBVIEW_DIALOG_FLAG_ERROR:
      type |= MB_ICONERROR;
      break;
    }
    MessageBox(w->priv.hwnd, arg, title, type);
#endif
  }
}

WEBVIEW_API void webview_terminate(struct webview *w) { PostQuitMessage(0); }
WEBVIEW_API void webview_exit(struct webview *w) { OleUninitialize(); }
WEBVIEW_API void webview_print_log(const char *s) { OutputDebugString(s); }

#endif /* WEBVIEW_WINAPI */

#if defined(WEBVIEW_COCOA)
#define NSAlertStyleWarning 0
#define NSAlertStyleCritical 2
#define NSWindowStyleMaskResizable 8
#define NSWindowStyleMaskMiniaturizable 4
#define NSWindowStyleMaskTitled 1
#define NSWindowStyleMaskClosable 2
#define NSWindowStyleMaskFullScreen (1 << 14)
#define NSViewWidthSizable 2
#define NSViewHeightSizable 16
#define NSBackingStoreBuffered 2
#define NSEventMaskAny ULONG_MAX
#define NSEventModifierFlagCommand (1 << 20)
#define NSEventModifierFlagOption (1 << 19)
#define NSAlertStyleInformational 1
#define NSAlertFirstButtonReturn 1000
#define WKNavigationActionPolicyDownload 2
#define NSModalResponseOK 1
#define WKNavigationActionPolicyDownload 2
#define WKNavigationResponsePolicyAllow 1
#define WKUserScriptInjectionTimeAtDocumentStart 0
#define NSApplicationActivationPolicyRegular 0

static id get_nsstring(const char *c_str) {
  return objc_msgSend((id)objc_getClass("NSString"),
                      sel_registerName("stringWithUTF8String:"), c_str);
}

static id create_menu_item(id title, const char *action, const char *key) {
  id item =
      objc_msgSend((id)objc_getClass("NSMenuItem"), sel_registerName("alloc"));
  objc_msgSend(item, sel_registerName("initWithTitle:action:keyEquivalent:"),
               title, sel_registerName(action), get_nsstring(key));
  objc_msgSend(item, sel_registerName("autorelease"));

  return item;
}

static void webview_window_will_close(id self, SEL cmd, id notification) {
  struct webview *w =
      (struct webview *)objc_getAssociatedObject(self, "webview");
  webview_terminate(w);
}

static void webview_external_invoke(id self, SEL cmd, id contentController,
                                    id message) {
  struct webview *w =
      (struct webview *)objc_getAssociatedObject(contentController, "webview");
  if (w == NULL || w->external_invoke_cb == NULL) {
    return;
  }

  w->external_invoke_cb(w, (const char *)objc_msgSend(
                               objc_msgSend(message, sel_registerName("body")),
                               sel_registerName("UTF8String")));
}

static void run_open_panel(id self, SEL cmd, id webView, id parameters,
                           id frame, void (^completionHandler)(id)) {

  id openPanel = objc_msgSend((id)objc_getClass("NSOpenPanel"),
                              sel_registerName("openPanel"));

  objc_msgSend(
      openPanel, sel_registerName("setAllowsMultipleSelection:"),
      objc_msgSend(parameters, sel_registerName("allowsMultipleSelection")));

  objc_msgSend(openPanel, sel_registerName("setCanChooseFiles:"), 1);
  objc_msgSend(
      openPanel, sel_registerName("beginWithCompletionHandler:"), ^(id result) {
        if (result == (id)NSModalResponseOK) {
          completionHandler(objc_msgSend(openPanel, sel_registerName("URLs")));
        } else {
          completionHandler(nil);
        }
      });
}

static void run_save_panel(id self, SEL cmd, id download, id filename,
                           void (^completionHandler)(int allowOverwrite,
                                                     id destination)) {
  id savePanel = objc_msgSend((id)objc_getClass("NSSavePanel"),
                              sel_registerName("savePanel"));
  objc_msgSend(savePanel, sel_registerName("setCanCreateDirectories:"), 1);
  objc_msgSend(savePanel, sel_registerName("setNameFieldStringValue:"),
               filename);
  objc_msgSend(savePanel, sel_registerName("beginWithCompletionHandler:"),
               ^(id result) {
                 if (result == (id)NSModalResponseOK) {
                   id url = objc_msgSend(savePanel, sel_registerName("URL"));
                   id path = objc_msgSend(url, sel_registerName("path"));
                   completionHandler(1, path);
                 } else {
                   completionHandler(NO, nil);
                 }
               });
}

static void run_confirmation_panel(id self, SEL cmd, id webView, id message,
                                   id frame, void (^completionHandler)(bool)) {

  id alert =
      objc_msgSend((id)objc_getClass("NSAlert"), sel_registerName("new"));
  objc_msgSend(alert, sel_registerName("setIcon:"),
               objc_msgSend((id)objc_getClass("NSImage"),
                            sel_registerName("imageNamed:"),
                            get_nsstring("NSCaution")));
  objc_msgSend(alert, sel_registerName("setShowsHelp:"), 0);
  objc_msgSend(alert, sel_registerName("setInformativeText:"), message);
  objc_msgSend(alert, sel_registerName("addButtonWithTitle:"),
               get_nsstring("OK"));
  objc_msgSend(alert, sel_registerName("addButtonWithTitle:"),
               get_nsstring("Cancel"));
  if (objc_msgSend(alert, sel_registerName("runModal")) ==
      (id)NSAlertFirstButtonReturn) {
    completionHandler(true);
  } else {
    completionHandler(false);
  }
  objc_msgSend(alert, sel_registerName("release"));
}

static void run_alert_panel(id self, SEL cmd, id webView, id message, id frame,
                            void (^completionHandler)(void)) {
  id alert =
      objc_msgSend((id)objc_getClass("NSAlert"), sel_registerName("new"));
  objc_msgSend(alert, sel_registerName("setIcon:"),
               objc_msgSend((id)objc_getClass("NSImage"),
                            sel_registerName("imageNamed:"),
                            get_nsstring("NSCaution")));
  objc_msgSend(alert, sel_registerName("setShowsHelp:"), 0);
  objc_msgSend(alert, sel_registerName("setInformativeText:"), message);
  objc_msgSend(alert, sel_registerName("addButtonWithTitle:"),
               get_nsstring("OK"));
  objc_msgSend(alert, sel_registerName("runModal"));
  objc_msgSend(alert, sel_registerName("release"));
  completionHandler();
}

static void download_failed(id self, SEL cmd, id download, id error) {
  printf("%s",
         (const char *)objc_msgSend(
             objc_msgSend(error, sel_registerName("localizedDescription")),
             sel_registerName("UTF8String")));
}

static void make_nav_policy_decision(id self, SEL cmd, id webView, id response,
                                     void (^decisionHandler)(int)) {
  if (objc_msgSend(response, sel_registerName("canShowMIMEType")) == 0) {
    decisionHandler(WKNavigationActionPolicyDownload);
  } else {
    decisionHandler(WKNavigationResponsePolicyAllow);
  }
}

WEBVIEW_API int webview_init(struct webview *w) {
  w->priv.pool = objc_msgSend((id)objc_getClass("NSAutoreleasePool"),
                              sel_registerName("new"));
  objc_msgSend((id)objc_getClass("NSApplication"),
               sel_registerName("sharedApplication"));

  Class __WKScriptMessageHandler = objc_allocateClassPair(
      objc_getClass("NSObject"), "__WKScriptMessageHandler", 0);
  class_addMethod(
      __WKScriptMessageHandler,
      sel_registerName("userContentController:didReceiveScriptMessage:"),
      (IMP)webview_external_invoke, "v@:@@");
  objc_registerClassPair(__WKScriptMessageHandler);

  id scriptMessageHandler =
      objc_msgSend((id)__WKScriptMessageHandler, sel_registerName("new"));

  /***
   _WKDownloadDelegate is an undocumented/private protocol with methods called
   from WKNavigationDelegate
   References:
   https://github.com/WebKit/webkit/blob/master/Source/WebKit/UIProcess/API/Cocoa/_WKDownload.h
   https://github.com/WebKit/webkit/blob/master/Source/WebKit/UIProcess/API/Cocoa/_WKDownloadDelegate.h
   https://github.com/WebKit/webkit/blob/master/Tools/TestWebKitAPI/Tests/WebKitCocoa/Download.mm
   ***/

  Class __WKDownloadDelegate = objc_allocateClassPair(
      objc_getClass("NSObject"), "__WKDownloadDelegate", 0);
  class_addMethod(
      __WKDownloadDelegate,
      sel_registerName("_download:decideDestinationWithSuggestedFilename:"
                       "completionHandler:"),
      (IMP)run_save_panel, "v@:@@?");
  class_addMethod(__WKDownloadDelegate,
                  sel_registerName("_download:didFailWithError:"),
                  (IMP)download_failed, "v@:@@");
  objc_registerClassPair(__WKDownloadDelegate);
  id downloadDelegate =
      objc_msgSend((id)__WKDownloadDelegate, sel_registerName("new"));

  Class __WKPreferences = objc_allocateClassPair(objc_getClass("WKPreferences"),
                                                 "__WKPreferences", 0);
  objc_property_attribute_t type = {"T", "c"};
  objc_property_attribute_t ownership = {"N", ""};
  objc_property_attribute_t attrs[] = {type, ownership};
  class_replaceProperty(__WKPreferences, "developerExtrasEnabled", attrs, 2);
  objc_registerClassPair(__WKPreferences);
  id wkPref = objc_msgSend((id)__WKPreferences, sel_registerName("new"));
  objc_msgSend(wkPref, sel_registerName("setValue:forKey:"),
               objc_msgSend((id)objc_getClass("NSNumber"),
                            sel_registerName("numberWithBool:"), !!w->debug),
               objc_msgSend((id)objc_getClass("NSString"),
                            sel_registerName("stringWithUTF8String:"),
                            "developerExtrasEnabled"));

  id userController = objc_msgSend((id)objc_getClass("WKUserContentController"),
                                   sel_registerName("new"));
  objc_setAssociatedObject(userController, "webview", (id)(w),
                           OBJC_ASSOCIATION_ASSIGN);
  objc_msgSend(
      userController, sel_registerName("addScriptMessageHandler:name:"),
      scriptMessageHandler,
      objc_msgSend((id)objc_getClass("NSString"),
                   sel_registerName("stringWithUTF8String:"), "invoke"));

  /***
   In order to maintain compatibility with the other 'webviews' we need to
   override window.external.invoke to call
   webkit.messageHandlers.invoke.postMessage
   ***/

  id windowExternalOverrideScript = objc_msgSend(
      (id)objc_getClass("WKUserScript"), sel_registerName("alloc"));
  objc_msgSend(
      windowExternalOverrideScript,
      sel_registerName("initWithSource:injectionTime:forMainFrameOnly:"),
      get_nsstring("window.external = this; invoke = function(arg){ "
                   "webkit.messageHandlers.invoke.postMessage(arg); };"),
      WKUserScriptInjectionTimeAtDocumentStart, 0);

  objc_msgSend(userController, sel_registerName("addUserScript:"),
               windowExternalOverrideScript);

  id config = objc_msgSend((id)objc_getClass("WKWebViewConfiguration"),
                           sel_registerName("new"));
  id processPool = objc_msgSend(config, sel_registerName("processPool"));
  objc_msgSend(processPool, sel_registerName("_setDownloadDelegate:"),
               downloadDelegate);
  objc_msgSend(config, sel_registerName("setProcessPool:"), processPool);
  objc_msgSend(config, sel_registerName("setUserContentController:"),
               userController);
  objc_msgSend(config, sel_registerName("setPreferences:"), wkPref);

  Class __NSWindowDelegate = objc_allocateClassPair(objc_getClass("NSObject"),
                                                    "__NSWindowDelegate", 0);
  class_addProtocol(__NSWindowDelegate, objc_getProtocol("NSWindowDelegate"));
  class_replaceMethod(__NSWindowDelegate, sel_registerName("windowWillClose:"),
                      (IMP)webview_window_will_close, "v@:@");
  objc_registerClassPair(__NSWindowDelegate);

  w->priv.windowDelegate =
      objc_msgSend((id)__NSWindowDelegate, sel_registerName("new"));

  objc_setAssociatedObject(w->priv.windowDelegate, "webview", (id)(w),
                           OBJC_ASSOCIATION_ASSIGN);

  id nsTitle =
      objc_msgSend((id)objc_getClass("NSString"),
                   sel_registerName("stringWithUTF8String:"), w->title);

  CGRect r = CGRectMake(0, 0, w->width, w->height);

  unsigned int style = NSWindowStyleMaskTitled | NSWindowStyleMaskClosable |
                       NSWindowStyleMaskMiniaturizable;
  if (w->resizable) {
    style = style | NSWindowStyleMaskResizable;
  }

  w->priv.window =
      objc_msgSend((id)objc_getClass("NSWindow"), sel_registerName("alloc"));
  objc_msgSend(w->priv.window,
               sel_registerName("initWithContentRect:styleMask:backing:defer:"),
               r, style, NSBackingStoreBuffered, 0);

  objc_msgSend(w->priv.window, sel_registerName("autorelease"));
  objc_msgSend(w->priv.window, sel_registerName("setTitle:"), nsTitle);
  objc_msgSend(w->priv.window, sel_registerName("setDelegate:"),
               w->priv.windowDelegate);
  objc_msgSend(w->priv.window, sel_registerName("center"));

  Class __WKUIDelegate =
      objc_allocateClassPair(objc_getClass("NSObject"), "__WKUIDelegate", 0);
  class_addProtocol(__WKUIDelegate, objc_getProtocol("WKUIDelegate"));
  class_addMethod(__WKUIDelegate,
                  sel_registerName("webView:runOpenPanelWithParameters:"
                                   "initiatedByFrame:completionHandler:"),
                  (IMP)run_open_panel, "v@:@@@?");
  class_addMethod(__WKUIDelegate,
                  sel_registerName("webView:runJavaScriptAlertPanelWithMessage:"
                                   "initiatedByFrame:completionHandler:"),
                  (IMP)run_alert_panel, "v@:@@@?");
  class_addMethod(
      __WKUIDelegate,
      sel_registerName("webView:runJavaScriptConfirmPanelWithMessage:"
                       "initiatedByFrame:completionHandler:"),
      (IMP)run_confirmation_panel, "v@:@@@?");
  objc_registerClassPair(__WKUIDelegate);
  id uiDel = objc_msgSend((id)__WKUIDelegate, sel_registerName("new"));

  Class __WKNavigationDelegate = objc_allocateClassPair(
      objc_getClass("NSObject"), "__WKNavigationDelegate", 0);
  class_addProtocol(__WKNavigationDelegate,
                    objc_getProtocol("WKNavigationDelegate"));
  class_addMethod(
      __WKNavigationDelegate,
      sel_registerName(
          "webView:decidePolicyForNavigationResponse:decisionHandler:"),
      (IMP)make_nav_policy_decision, "v@:@@?");
  objc_registerClassPair(__WKNavigationDelegate);
  id navDel = objc_msgSend((id)__WKNavigationDelegate, sel_registerName("new"));

  w->priv.webview =
      objc_msgSend((id)objc_getClass("WKWebView"), sel_registerName("alloc"));
  objc_msgSend(w->priv.webview,
               sel_registerName("initWithFrame:configuration:"), r, config);
  objc_msgSend(w->priv.webview, sel_registerName("setUIDelegate:"), uiDel);
  objc_msgSend(w->priv.webview, sel_registerName("setNavigationDelegate:"),
               navDel);

  id nsURL = objc_msgSend((id)objc_getClass("NSURL"),
                          sel_registerName("URLWithString:"),
                          get_nsstring(webview_check_url(w->url)));

  objc_msgSend(w->priv.webview, sel_registerName("loadRequest:"),
               objc_msgSend((id)objc_getClass("NSURLRequest"),
                            sel_registerName("requestWithURL:"), nsURL));
  objc_msgSend(w->priv.webview, sel_registerName("setAutoresizesSubviews:"), 1);
  objc_msgSend(w->priv.webview, sel_registerName("setAutoresizingMask:"),
               (NSViewWidthSizable | NSViewHeightSizable));
  objc_msgSend(objc_msgSend(w->priv.window, sel_registerName("contentView")),
               sel_registerName("addSubview:"), w->priv.webview);
  objc_msgSend(w->priv.window, sel_registerName("orderFrontRegardless"));

  objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                            sel_registerName("sharedApplication")),
               sel_registerName("setActivationPolicy:"),
               NSApplicationActivationPolicyRegular);

  objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                            sel_registerName("sharedApplication")),
               sel_registerName("finishLaunching"));

  objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                            sel_registerName("sharedApplication")),
               sel_registerName("activateIgnoringOtherApps:"), 1);

  id menubar =
      objc_msgSend((id)objc_getClass("NSMenu"), sel_registerName("alloc"));
  objc_msgSend(menubar, sel_registerName("initWithTitle:"), get_nsstring(""));
  objc_msgSend(menubar, sel_registerName("autorelease"));

  id appName = objc_msgSend(objc_msgSend((id)objc_getClass("NSProcessInfo"),
                                         sel_registerName("processInfo")),
                            sel_registerName("processName"));

  id appMenuItem =
      objc_msgSend((id)objc_getClass("NSMenuItem"), sel_registerName("alloc"));
  objc_msgSend(appMenuItem,
               sel_registerName("initWithTitle:action:keyEquivalent:"), appName,
               NULL, get_nsstring(""));

  id appMenu =
      objc_msgSend((id)objc_getClass("NSMenu"), sel_registerName("alloc"));
  objc_msgSend(appMenu, sel_registerName("initWithTitle:"), appName);
  objc_msgSend(appMenu, sel_registerName("autorelease"));

  objc_msgSend(appMenuItem, sel_registerName("setSubmenu:"), appMenu);
  objc_msgSend(menubar, sel_registerName("addItem:"), appMenuItem);

  id title =
      objc_msgSend(get_nsstring("Hide "),
                   sel_registerName("stringByAppendingString:"), appName);
  id item = create_menu_item(title, "hide:", "h");
  objc_msgSend(appMenu, sel_registerName("addItem:"), item);

  item = create_menu_item(get_nsstring("Hide Others"),
                          "hideOtherApplications:", "h");
  objc_msgSend(item, sel_registerName("setKeyEquivalentModifierMask:"),
               (NSEventModifierFlagOption | NSEventModifierFlagCommand));
  objc_msgSend(appMenu, sel_registerName("addItem:"), item);

  item =
      create_menu_item(get_nsstring("Show All"), "unhideAllApplications:", "");
  objc_msgSend(appMenu, sel_registerName("addItem:"), item);

  objc_msgSend(appMenu, sel_registerName("addItem:"),
               objc_msgSend((id)objc_getClass("NSMenuItem"),
                            sel_registerName("separatorItem")));

  title = objc_msgSend(get_nsstring("Quit "),
                       sel_registerName("stringByAppendingString:"), appName);
  item = create_menu_item(title, "terminate:", "q");
  objc_msgSend(appMenu, sel_registerName("addItem:"), item);

  objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                            sel_registerName("sharedApplication")),
               sel_registerName("setMainMenu:"), menubar);

  w->priv.should_exit = 0;
  return 0;
}

WEBVIEW_API int webview_loop(struct webview *w, int blocking) {
  id until = (blocking ? objc_msgSend((id)objc_getClass("NSDate"),
                                      sel_registerName("distantFuture"))
                       : objc_msgSend((id)objc_getClass("NSDate"),
                                      sel_registerName("distantPast")));

  id event = objc_msgSend(
      objc_msgSend((id)objc_getClass("NSApplication"),
                   sel_registerName("sharedApplication")),
      sel_registerName("nextEventMatchingMask:untilDate:inMode:dequeue:"),
      ULONG_MAX, until,
      objc_msgSend((id)objc_getClass("NSString"),
                   sel_registerName("stringWithUTF8String:"),
                   "kCFRunLoopDefaultMode"),
      true);

  if (event) {
    objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                              sel_registerName("sharedApplication")),
                 sel_registerName("sendEvent:"), event);
  }

  return w->priv.should_exit;
}

WEBVIEW_API int webview_eval(struct webview *w, const char *js) {
  objc_msgSend(w->priv.webview,
               sel_registerName("evaluateJavaScript:completionHandler:"),
               get_nsstring(js), NULL);

  return 0;
}

WEBVIEW_API void webview_set_title(struct webview *w, const char *title) {
  objc_msgSend(w->priv.window, sel_registerName("setTitle:"),
               get_nsstring(title));
}

WEBVIEW_API void webview_set_fullscreen(struct webview *w, int fullscreen) {
  unsigned long windowStyleMask = (unsigned long)objc_msgSend(
      w->priv.window, sel_registerName("styleMask"));
  int b = (((windowStyleMask & NSWindowStyleMaskFullScreen) ==
            NSWindowStyleMaskFullScreen)
               ? 1
               : 0);
  if (b != fullscreen) {
    objc_msgSend(w->priv.window, sel_registerName("toggleFullScreen:"), NULL);
  }
}

WEBVIEW_API void webview_set_color(struct webview *w, uint8_t r, uint8_t g,
                                   uint8_t b, uint8_t a) {

  id color = objc_msgSend((id)objc_getClass("NSColor"),
                          sel_registerName("colorWithRed:green:blue:alpha:"),
                          (float)r / 255.0, (float)g / 255.0, (float)b / 255.0,
                          (float)a / 255.0);

  objc_msgSend(w->priv.window, sel_registerName("setBackgroundColor:"), color);

  if (0.5 >= ((r / 255.0 * 299.0) + (g / 255.0 * 587.0) + (b / 255.0 * 114.0)) /
                 1000.0) {
    objc_msgSend(w->priv.window, sel_registerName("setAppearance:"),
                 objc_msgSend((id)objc_getClass("NSAppearance"),
                              sel_registerName("appearanceNamed:"),
                              get_nsstring("NSAppearanceNameVibrantDark")));
  } else {
    objc_msgSend(w->priv.window, sel_registerName("setAppearance:"),
                 objc_msgSend((id)objc_getClass("NSAppearance"),
                              sel_registerName("appearanceNamed:"),
                              get_nsstring("NSAppearanceNameVibrantLight")));
  }
  objc_msgSend(w->priv.window, sel_registerName("setOpaque:"), 0);
  objc_msgSend(w->priv.window,
               sel_registerName("setTitlebarAppearsTransparent:"), 1);
}

WEBVIEW_API void webview_dialog(struct webview *w,
                                enum webview_dialog_type dlgtype, int flags,
                                const char *title, const char *arg,
                                char *result, size_t resultsz) {
  if (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN ||
      dlgtype == WEBVIEW_DIALOG_TYPE_SAVE) {
    id panel = (id)objc_getClass("NSSavePanel");
    if (dlgtype == WEBVIEW_DIALOG_TYPE_OPEN) {
      id openPanel = objc_msgSend((id)objc_getClass("NSOpenPanel"),
                                  sel_registerName("openPanel"));
      if (flags & WEBVIEW_DIALOG_FLAG_DIRECTORY) {
        objc_msgSend(openPanel, sel_registerName("setCanChooseFiles:"), 0);
        objc_msgSend(openPanel, sel_registerName("setCanChooseDirectories:"),
                     1);
      } else {
        objc_msgSend(openPanel, sel_registerName("setCanChooseFiles:"), 1);
        objc_msgSend(openPanel, sel_registerName("setCanChooseDirectories:"),
                     0);
      }
      objc_msgSend(openPanel, sel_registerName("setResolvesAliases:"), 0);
      objc_msgSend(openPanel, sel_registerName("setAllowsMultipleSelection:"),
                   0);
      panel = openPanel;
    } else {
      panel = objc_msgSend((id)objc_getClass("NSSavePanel"),
                           sel_registerName("savePanel"));
    }

    objc_msgSend(panel, sel_registerName("setCanCreateDirectories:"), 1);
    objc_msgSend(panel, sel_registerName("setShowsHiddenFiles:"), 1);
    objc_msgSend(panel, sel_registerName("setExtensionHidden:"), 0);
    objc_msgSend(panel, sel_registerName("setCanSelectHiddenExtension:"), 0);
    objc_msgSend(panel, sel_registerName("setTreatsFilePackagesAsDirectories:"),
                 1);
    objc_msgSend(
        panel, sel_registerName("beginSheetModalForWindow:completionHandler:"),
        w->priv.window, ^(id result) {
          objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                                    sel_registerName("sharedApplication")),
                       sel_registerName("stopModalWithCode:"), result);
        });

    if (objc_msgSend(objc_msgSend((id)objc_getClass("NSApplication"),
                                  sel_registerName("sharedApplication")),
                     sel_registerName("runModalForWindow:"),
                     panel) == (id)NSModalResponseOK) {
      id url = objc_msgSend(panel, sel_registerName("URL"));
      id path = objc_msgSend(url, sel_registerName("path"));
      const char *filename =
          (const char *)objc_msgSend(path, sel_registerName("UTF8String"));
      strlcpy(result, filename, resultsz);
    }
  } else if (dlgtype == WEBVIEW_DIALOG_TYPE_ALERT) {
    id a = objc_msgSend((id)objc_getClass("NSAlert"), sel_registerName("new"));
    switch (flags & WEBVIEW_DIALOG_FLAG_ALERT_MASK) {
    case WEBVIEW_DIALOG_FLAG_INFO:
      objc_msgSend(a, sel_registerName("setAlertStyle:"),
                   NSAlertStyleInformational);
      break;
    case WEBVIEW_DIALOG_FLAG_WARNING:
      printf("Warning\n");
      objc_msgSend(a, sel_registerName("setAlertStyle:"), NSAlertStyleWarning);
      break;
    case WEBVIEW_DIALOG_FLAG_ERROR:
      printf("Error\n");
      objc_msgSend(a, sel_registerName("setAlertStyle:"), NSAlertStyleCritical);
      break;
    }
    objc_msgSend(a, sel_registerName("setShowsHelp:"), 0);
    objc_msgSend(a, sel_registerName("setShowsSuppressionButton:"), 0);
    objc_msgSend(a, sel_registerName("setMessageText:"), get_nsstring(title));
    objc_msgSend(a, sel_registerName("setInformativeText:"), get_nsstring(arg));
    objc_msgSend(a, sel_registerName("addButtonWithTitle:"),
                 get_nsstring("OK"));
    objc_msgSend(a, sel_registerName("runModal"));
    objc_msgSend(a, sel_registerName("release"));
  }
}

static void webview_dispatch_cb(void *arg) {
  struct webview_dispatch_arg *context = (struct webview_dispatch_arg *)arg;
  (context->fn)(context->w, context->arg);
  free(context);
}

WEBVIEW_API void webview_dispatch(struct webview *w, webview_dispatch_fn fn,
                                  void *arg) {
  struct webview_dispatch_arg *context = (struct webview_dispatch_arg *)malloc(
      sizeof(struct webview_dispatch_arg));
  context->w = w;
  context->arg = arg;
  context->fn = fn;
  dispatch_async_f(dispatch_get_main_queue(), context, webview_dispatch_cb);
}

WEBVIEW_API void webview_terminate(struct webview *w) {
  w->priv.should_exit = 1;
}

WEBVIEW_API void webview_exit(struct webview *w) {
  id app = objc_msgSend((id)objc_getClass("NSApplication"),
                        sel_registerName("sharedApplication"));
  objc_msgSend(app, sel_registerName("terminate:"), app);
}

WEBVIEW_API void webview_print_log(const char *s) { printf("%s\n", s); }

#endif /* WEBVIEW_COCOA */

#endif /* WEBVIEW_IMPLEMENTATION */

#ifdef __cplusplus
}
#endif

#endif /* WEBVIEW_H */