#if 0
libdecor_path="/home/mr4th/mr4th/libdecor"
root_path="$PWD"
dbus_flags="$(pkg-config --cflags --libs dbus-1)"
my_flags="-Iwayland -I$libdecor_path/src -I$libdecor_path/src/plugins -I$libdecor_path/build"
my_flags+=" -lwayland-client -lwayland-cursor -lwayland-egl -lEGL -lm"
mkdir -p build
clang -o build/demo -g $root_path/wayland_egl.c $dbus_flags $my_flags
exit 0
#endif


#define _GNU_SOURCE

#include <wayland-client.h>
#include <wayland-client-core.h>
#include <wayland-cursor.h>

#include <wayland-egl.h>
/*~ NOTE: wayland-egl.h *before* EGL/ */
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <GL/glcorearb.h>

#include <errno.h>
#include <dirent.h>
#include <dlfcn.h>
#include <sys/types.h>
#include <poll.h>
#include <math.h>
#include <linux/input.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <signal.h>

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

#include "xdg-shell-client-protocol.h"
#include "xdg-decoration-client-protocol.h"

#include "xdg-shell-client-protocol.c"
#include "xdg-decoration-client-protocol.c"

#include "wayland_egl.h"

// X(N:name,R:return,P:params)
#define GL_FUNCS_XLIST(X)\
X(glDrawBuffer, void, (GLenum buf)) \
X(glViewport, void, (GLint x, GLint y, GLsizei w, GLsizei h)) \
X(glClear, void, (GLbitfield mask)) \
X(glClearColor, void, (GLfloat r, GLfloat g, GLfloat b, GLfloat a))

#define X(N,R,P) R (*N)P = 0;
GL_FUNCS_XLIST(X)
#undef X

static Ctx ctx = {0};

static void
shm_format(void *udata, struct wl_shm *wl_shm, uint32_t format){
}

const struct wl_shm_listener shm_listener = {
  shm_format
};

static void
xdg_wm_base_ping(void *udata, struct xdg_wm_base *xdg_wm_base, uint32_t serial){
  xdg_wm_base_pong(xdg_wm_base, serial);
}

const struct xdg_wm_base_listener xdg_wm_base_listener = {
  xdg_wm_base_ping
};

#define SHADOW_MARGIN 20
#define SHADOW_THICK  10

static void
pointer_enter(void *udata, struct wl_pointer *wl_pointer, uint32_t serial,
              struct wl_surface *surface, wl_fixed_t fx, wl_fixed_t fy){
  int x = ctx.p[0] = wl_fixed_to_int(fx);
  int y = ctx.p[1] = wl_fixed_to_int(fy);
  ctx.hover = surface;
  if (surface == ctx.main_wl_surface){
    printf("pointer_enter (main) %d,%d\n", x, y);
  }
  else if (surface == ctx.shadow_wl_surface){
    printf("pointer_enter (shadow) %d,%d\n", x, y);
  }
  else{
    printf("pointer_enter (unidentified) %d,%d\n", x, y);
    ctx.hover = 0;
  }
  ctx.hover_serial = serial;
}

static void
pointer_leave(void *udata, struct wl_pointer *wl_pointer, uint32_t serial,
              struct wl_surface *surface){
  if (surface == ctx.main_wl_surface){
    printf("pointer_leave (main)\n");
  }
  else if (surface == ctx.shadow_wl_surface){
    printf("pointer_leave (shadow)\n");
  }
  else{
    printf("pointer_leave (unidentified)\n");
  }
  ctx.hover = 0;
}

static void
pointer_motion(void *udata, struct wl_pointer *wl_pointer, uint32_t time,
               wl_fixed_t fx, wl_fixed_t fy){
  int x = ctx.p[0] = wl_fixed_to_int(fx);
  int y = ctx.p[1] = wl_fixed_to_int(fy);
  printf("pointer_motion %d,%d\n", x, y);
}

static void
pointer_button(void *udata, struct wl_pointer *wl_pointer, uint32_t serial,
               uint32_t time, uint32_t button, uint32_t state){
  char *state_str = (state == 1?"press":"release");
  if (button == BTN_LEFT){
    printf("pointer_button (left) %s\n", state_str);
  }
  else if (button == BTN_RIGHT){
    printf("pointer_button (right) %s\n", state_str);
  }
  else if (button == BTN_MIDDLE){
    printf("pointer_button (middle) %s\n", state_str);
  }
  else{
    printf("pointer_button (unidentified) %s\n", state_str);
  }
  if (state){
    ctx.button = button;
    ctx.button_serial = serial;
  }
}

static void
pointer_axis(void *udata, struct wl_pointer *wl_pointer,
             uint32_t time, uint32_t axis, wl_fixed_t fv){
  int v = wl_fixed_to_int(fv);
  printf("pointer_axis %u,%d\n", axis, v);
}

const struct wl_pointer_listener pointer_listener = {
  pointer_enter,
  pointer_leave,
  pointer_motion,
  pointer_button,
  pointer_axis
};

static void
seat_capabilities(void *udata, struct wl_seat *wl_seat, uint32_t capabilities){
  if ((capabilities & WL_SEAT_CAPABILITY_POINTER) && ctx.wl_pointer == 0){
    ctx.wl_pointer = wl_seat_get_pointer(ctx.wl_seat);
    wl_pointer_add_listener(ctx.wl_pointer, &pointer_listener, 0);
  }
  else if (!(capabilities & WL_SEAT_CAPABILITY_POINTER) && ctx.wl_pointer != 0){
    wl_pointer_release(ctx.wl_pointer);
    ctx.wl_pointer = 0;
  }
}

static void
seat_name(void *udata, struct wl_seat *wl_seat, const char *name){
}

const struct wl_seat_listener seat_listener = {
  seat_capabilities,
  seat_name
};

static void
registry_global(void *udata, struct wl_registry *wl_registry,
                uint32_t name, const char *interface,
                uint32_t version){
  if (strcmp(interface, "wl_compositor") == 0){
    ctx.wl_compositor = (struct wl_compositor*)
      wl_registry_bind(wl_registry, name, &wl_compositor_interface, Min(version, 4));
  }
  else if (strcmp(interface, "wl_subcompositor") == 0){
    ctx.wl_subcompositor = wl_registry_bind(ctx.wl_registry, name, &wl_subcompositor_interface, 1);
  }
  else if (strcmp(interface, "wl_shm") == 0){
    ctx.wl_shm = wl_registry_bind(ctx.wl_registry, name, &wl_shm_interface, 1);
    wl_shm_add_listener(ctx.wl_shm, &shm_listener, 0);
  }
  else if (!strcmp(interface, xdg_wm_base_interface.name)){
    ctx.xdg_wm_base = wl_registry_bind(ctx.wl_registry, name, &xdg_wm_base_interface, Min(version, 2));
    xdg_wm_base_add_listener(ctx.xdg_wm_base, &xdg_wm_base_listener, 0);
  }
  else if (!strcmp(interface, zxdg_decoration_manager_v1_interface.name)){
    ctx.zxdg_decoration_manager = wl_registry_bind(wl_registry, name, &zxdg_decoration_manager_v1_interface, Min(version, 2));
  }
  else if (strcmp(interface, "wl_seat") == 0){
    ctx.wl_seat = wl_registry_bind(ctx.wl_registry, name, &wl_seat_interface, 3);
    wl_seat_add_listener(ctx.wl_seat, &seat_listener, 0);
    ctx.cursor_surface = wl_compositor_create_surface(ctx.wl_compositor);
  }
}

static void
registry_global_remove(void *udata, struct wl_registry *registry,
                       uint32_t name){
}

const struct wl_registry_listener registry_listener = {
  registry_global,
  registry_global_remove,
};

static void
xdg_surface_configure(void *udata, struct xdg_surface *xdg_surface,
                      uint32_t serial){
  ctx.config_staged.serial = serial;
}

const struct xdg_surface_listener xdg_surface_listener = { xdg_surface_configure, };

static void
xdg_toplevel_configure(void *udata, struct xdg_toplevel *xdg_toplevel,
                       int32_t width, int32_t height, struct wl_array *states){
  if (width != 0 && height != 0){
    ctx.config_staged.dim[0] = width;
    ctx.config_staged.dim[1] = height;
  }
  else{
    ctx.config_staged.dim[0] = ctx.config.dim[0];
    ctx.config_staged.dim[1] = ctx.config.dim[1];
  }
  ctx.config_staged.flags = window_flags_from_states_array(states);
}

static void
xdg_toplevel_close(void *udata, struct xdg_toplevel *xdg_toplevel){
  ctx.close_signal = 1;
}

static void
xdg_toplevel_configure_bounds(void *udata, struct xdg_toplevel *xdg_toplevel,
                              int32_t w, int32_t h){
}

static void
xdg_toplevel_wm_capabilities(void *udata, struct xdg_toplevel *xdg_toplevel,
                             struct wl_array *capabilities){
}

const struct xdg_toplevel_listener xdg_toplevel_listener = {
  xdg_toplevel_configure,
  xdg_toplevel_close,
  xdg_toplevel_configure_bounds,
  xdg_toplevel_wm_capabilities,
};

static void
xdg_toplevel_decoration_configure(void *udata, struct zxdg_toplevel_decoration_v1 *toplevel,
                                  uint32_t mode){
  ctx.config_staged.decoration_mode = mode;
}

const struct zxdg_toplevel_decoration_v1_listener zxdg_toplevel_decoration_listener = {
  xdg_toplevel_decoration_configure
};

int main(){
  /* desktop settings */
  ctx.color_scheme = ds_get_color_scheme();
  ctx.cursor_theme = ds_get_cursor_theme();
  
  /* setup Wayland */
  {
    ctx.wl_display = wl_display_connect(0);
    ctx.wl_registry = wl_display_get_registry(ctx.wl_display);
    wl_registry_add_listener(ctx.wl_registry, &registry_listener, 0);
    
    wl_display_flush(ctx.wl_display);
    wl_display_dispatch(ctx.wl_display);
    
    ctx.wl_cursor_theme = wl_cursor_theme_load(ctx.cursor_theme.name,
                                               ctx.cursor_theme.size,
                                               ctx.wl_shm);
    
#define X(k,n) ctx.wl_cursors[k] = wl_cursor_theme_get_cursor(ctx.wl_cursor_theme, n);
    X(CursorShape_Pointer,            "left_ptr");
    X(CursorShape_Resize_Top,         "top_side");
    X(CursorShape_Resize_Bottom,      "bottom_side");
    X(CursorShape_Resize_Left,        "left_side");
    X(CursorShape_Resize_Right,       "right_side");
    X(CursorShape_Resize_TopLeft,     "top_left_corner");
    X(CursorShape_Resize_BottomLeft,  "bottom_left_corner");
    X(CursorShape_Resize_TopRight,    "top_right_corner");
    X(CursorShape_Resize_BottomRight, "bottom_right_corner");
#undef X
  }
  
  /* setup EGL */
  {
    ctx.egl_display = eglGetDisplay(ctx.wl_display);
    
    EGLint major = 0, minor = 0;
    eglInitialize(ctx.egl_display, &major, &minor);
    eglBindAPI(EGL_OPENGL_API);
    
    {
      EGLint attr[] = {
        EGL_CONTEXT_MAJOR_VERSION, 3,
        EGL_CONTEXT_MINOR_VERSION, 3,
        EGL_CONTEXT_OPENGL_PROFILE_MASK, EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT,
        EGL_NONE,
      };
      ctx.egl_context = eglCreateContext(ctx.egl_display, EGL_NO_CONFIG_KHR, EGL_NO_CONTEXT, attr);
    }
    
    eglMakeCurrent(ctx.egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE, ctx.egl_context);
    
#define X(N,R,P) N = (R(*)P)(eglGetProcAddress(#N));
    GL_FUNCS_XLIST(X)
#undef X
  }
  
  /* create a window */
  {
    /* window main surface */
    ctx.main_wl_surface = wl_compositor_create_surface(ctx.wl_compositor);
    ctx.main_xdg_surface = xdg_wm_base_get_xdg_surface(ctx.xdg_wm_base, ctx.main_wl_surface);
    xdg_surface_add_listener(ctx.main_xdg_surface, &xdg_surface_listener, 0);
    ctx.main_xdg_toplevel = xdg_surface_get_toplevel(ctx.main_xdg_surface);
    xdg_toplevel_add_listener(ctx.main_xdg_toplevel, &xdg_toplevel_listener, 0);
    
    ctx.control_flags = ~0;
    
    ctx.dim[0] = 640;
    ctx.dim[1] = 480;
    ctx.config_staged.decoration_mode = ZXDG_TOPLEVEL_DECORATION_V1_MODE_CLIENT_SIDE;
    if (ctx.zxdg_decoration_manager != 0){
      ctx.main_zxdg_toplevel_decoration = zxdg_decoration_manager_v1_get_toplevel_decoration(ctx.zxdg_decoration_manager, ctx.main_xdg_toplevel);
      zxdg_toplevel_decoration_v1_add_listener(ctx.main_zxdg_toplevel_decoration, &zxdg_toplevel_decoration_listener, 0);
    }
    
    for (int k = 0; k < 2; k += 1){
      ctx.mmbox[k][0] = 0;
      ctx.mmbox[k][1] = (1 << 30);
    }
    
    xdg_toplevel_set_app_id(ctx.main_xdg_toplevel, "demo");
    xdg_toplevel_set_title(ctx.main_xdg_toplevel, "Example Window");
    wl_surface_commit(ctx.main_wl_surface);
    
    /* window subsurface */
    ctx.shadow_wl_surface = wl_compositor_create_surface(ctx.wl_compositor);
    ctx.shadow_wl_subsurface =
      wl_subcompositor_get_subsurface(ctx.wl_subcompositor,
                                      ctx.shadow_wl_surface,
                                      ctx.main_wl_surface);
    
    /* window egl */
    ctx.main_wl_egl_window = wl_egl_window_create(ctx.main_wl_surface,
                                                  ctx.dim[0], ctx.dim[1]);
    
    EGLConfig configs[64];
    EGLint config_cap = sizeof(configs)/sizeof(*configs);
    EGLint config_count = 0;
    {
      EGLint attributes[] = {
        EGL_SURFACE_TYPE,      EGL_WINDOW_BIT,
        EGL_CONFORMANT,        EGL_OPENGL_BIT,
        EGL_RENDERABLE_TYPE,   EGL_OPENGL_BIT,
        EGL_COLOR_BUFFER_TYPE, EGL_RGB_BUFFER,
        EGL_RED_SIZE,      8,
        EGL_GREEN_SIZE,    8,
        EGL_BLUE_SIZE,     8,
        EGL_DEPTH_SIZE,   24,
        EGL_STENCIL_SIZE,  8,
        EGL_NONE,
      };
      eglChooseConfig(ctx.egl_display, attributes, configs, config_cap, &config_count);
    }
    
    {
      EGLint attributes[] = {
        EGL_RENDER_BUFFER, EGL_BACK_BUFFER,
        EGL_NONE,
      };
      for (EGLint i = 0; i < config_count; i += 1){
        ctx.main_egl_surface = eglCreateWindowSurface(ctx.egl_display, configs[i], ctx.main_wl_egl_window, attributes);
        if (ctx.main_egl_surface != EGL_NO_SURFACE){
          break;
        }
      }
    }
    
    eglMakeCurrent(ctx.egl_display, ctx.main_egl_surface, 
                   ctx.main_egl_surface, ctx.egl_context);
    
    eglSwapInterval(ctx.egl_display, 1);
  }
  
  /* main loop */
  int exit_loop = 0;
  for (;!exit_loop;){
    /* poll for events */
    {
      struct pollfd fds[1] = {0};
      
      /* register fds[0] ~ wayland events */
      bool wayland_started_read = false;
      bool wayland_did_read = false;
      {
        fds[0].fd = -1;
        
        wl_display_dispatch_pending(ctx.wl_display);
        wayland_started_read = (wl_display_prepare_read(ctx.wl_display) != -1);
        if (wayland_started_read){
          fds[0].fd = wl_display_get_fd(ctx.wl_display);
          fds[0].events = POLLIN;
          wl_display_flush(ctx.wl_display);
        }
      }
      
      /* poll and handle events */
      int ret = poll(fds, sizeof(fds)/sizeof(*fds), 0);
      if (ret > 0){
        
        /* handle fds[0] ~ wayland events */
        if (fds[0].revents & POLLIN){
          wayland_did_read = true;
          wl_display_read_events(ctx.wl_display);
          wl_display_dispatch_pending(ctx.wl_display);
        }
      }
      
      /* wayland event read cleanup */
      if (wayland_started_read && !wayland_did_read){
        wl_display_cancel_read(ctx.wl_display);
      }
    }
    
    /* apply config */
    if (ctx.config.serial != ctx.config_staged.serial){
      ctx.config = ctx.config_staged;
      xdg_surface_ack_configure(ctx.main_xdg_surface, ctx.config.serial);
    }
    
    int csd = (ctx.config.decoration_mode ==
               ZXDG_TOPLEVEL_DECORATION_V1_MODE_CLIENT_SIDE);
    
    /* window sizing */
    CSD_Frame csd_frame = {0};
    int32_t csd_dim[2] = {0};
    {
      if (csd){
        csd_frame = csd_impl_calculate_frame();
      }
      for (int i = 0; i < 2; i += 1){
        csd_dim[i] = csd_frame.border[i][0] + csd_frame.border[i][1];
      }
      for (int i = 0; i < 2; i += 1){
        int32_t d = ctx.config.dim[i] - csd_dim[i];
        if (!ctx.handled_first_size){
          d = ctx.dim[i];
          ctx.config.dim[i] = d + csd_dim[i];
        }
        d = ClampBot(d, ctx.mmbox[i][0]);
        d = ClampTop(d, ctx.mmbox[i][1]);
        d = ClampBot(d, csd_frame.minbox[i]);
        ctx.dim[i] = d;
      }
      ctx.handled_first_size = 1;
    }
    
    /* frame cursor & interaction */
    CursorShape cursor_shape = CursorShape_Pointer;
    if (ctx.control_flags & WindowControlFlag_Resize){
      static const CursorShape cursor_box[] = {
        CursorShape_Resize_TopLeft,    CursorShape_Resize_Top,    CursorShape_Resize_TopRight,
        CursorShape_Resize_Left,       CursorShape_Pointer,       CursorShape_Resize_Right,
        CursorShape_Resize_BottomLeft, CursorShape_Resize_Bottom, CursorShape_Resize_BottomRight,
      };
      
      static const enum xdg_toplevel_resize_edge xedge_box[] = {
        XDG_TOPLEVEL_RESIZE_EDGE_TOP_LEFT,    XDG_TOPLEVEL_RESIZE_EDGE_TOP,    XDG_TOPLEVEL_RESIZE_EDGE_TOP_RIGHT,
        XDG_TOPLEVEL_RESIZE_EDGE_LEFT,        XDG_TOPLEVEL_RESIZE_EDGE_NONE,   XDG_TOPLEVEL_RESIZE_EDGE_RIGHT,
        XDG_TOPLEVEL_RESIZE_EDGE_BOTTOM_LEFT, XDG_TOPLEVEL_RESIZE_EDGE_BOTTOM, XDG_TOPLEVEL_RESIZE_EDGE_BOTTOM_RIGHT,
      };
      
      int l = (ctx.p[0] < SHADOW_MARGIN);
      int r = (!l && ctx.p[0] >= ctx.dim[0] + SHADOW_MARGIN);
      int t = (ctx.p[1] < SHADOW_MARGIN);
      int b = (!t && ctx.p[1] >= ctx.dim[1] + SHADOW_MARGIN);
      int loc = 3*(b - t) + (r - l);
      cursor_shape = cursor_box[4 + loc];
      if (ctx.button == BTN_LEFT){
        ctx.button = 0;
        if (loc != 0){
          xdg_toplevel_resize(ctx.main_xdg_toplevel, ctx.wl_seat,
                              ctx.button_serial, xedge_box[4 + loc]);
        }
        else{
          xdg_toplevel_move(ctx.main_xdg_toplevel, ctx.wl_seat,
                            ctx.button_serial);
        }
      }
    }
    
    /* window frame render */
    if (csd){
      if (ctx.shadow_data != 0){
        munmap(ctx.shadow_data, ctx.shadow_size);
        ctx.shadow_data = 0;
      }
      if (ctx.shadow_wl_buffer != 0){
        wl_buffer_destroy(ctx.shadow_wl_buffer);
        ctx.shadow_wl_buffer = 0;
      }
      
      {
        int dim[2];
        for (int i = 0; i < 2; i += 1){
          dim[i] = ctx.dim[i] + SHADOW_MARGIN*2;
        }
        
        int stride = 4*dim[0];
        uint64_t size = 4*dim[0]*dim[1];
        
        int fd = os_create_anonymous_file(size);
        if (fd >= 0){
          void *data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
          if (data != MAP_FAILED){
            struct wl_shm_pool *pool = wl_shm_create_pool(ctx.wl_shm, fd, size);
            struct wl_buffer *wl_buffer =
              wl_shm_pool_create_buffer(pool, 0, dim[0], dim[1],
                                        stride, WL_SHM_FORMAT_ARGB8888);
            wl_shm_pool_destroy(pool);
            
            ctx.shadow_wl_buffer = wl_buffer;
            ctx.shadow_data = data;
            ctx.shadow_size = size;
            for (int i = 0; i < 2; i += 1){
              ctx.shadow_dim[i] = dim[i];
            }
          }
          
          close(fd);
        }
      }
      
      uint32_t *pxl = (uint32_t*)ctx.shadow_data;
      for (int32_t y = 0; y < ctx.shadow_dim[1]; y += 1){
        for (int32_t x = 0; x < ctx.shadow_dim[0]; x += 1){
          *pxl = 0;
          
          {
            int x0 = SHADOW_MARGIN - SHADOW_THICK;
            int y0 = SHADOW_MARGIN - SHADOW_THICK;
            int x1 = x0 + ctx.dim[0] + SHADOW_THICK*2;
            int y1 = y0 + ctx.dim[1] + SHADOW_THICK*2;
            
            if (x0 <= x && x < x1 && y0 <= y && y < y1){
              int xd0 = x - x0;
              int xd1 = x1 - x - 1;
              int yd0 = y - y0;
              int yd1 = y1 - y - 1;
              int d = Min(Min(xd0, xd1), Min(yd0, yd1));
              
              if (d < SHADOW_THICK){
                int c = d*0xFF/SHADOW_THICK;
                ((uint8_t*)pxl)[0] = 0;
                ((uint8_t*)pxl)[1] = 0;
                ((uint8_t*)pxl)[2] = 0;
                ((uint8_t*)pxl)[3] = c;
              }
            }
          }
          pxl += 1;
        }
      }
      
      {
        struct wl_region *region = wl_compositor_create_region(ctx.wl_compositor);
        wl_region_add(region, 0, 0, ctx.shadow_dim[0], ctx.shadow_dim[1]);
        wl_region_subtract(region, SHADOW_MARGIN, SHADOW_MARGIN,
                           ctx.dim[0], ctx.dim[1]);
        wl_surface_set_input_region(ctx.shadow_wl_surface, region);
        wl_region_destroy(region);
      }
      
      {
        wl_surface_attach(ctx.shadow_wl_surface, ctx.shadow_wl_buffer, 0, 0);
        wl_surface_set_buffer_scale(ctx.shadow_wl_surface, 1);
        wl_surface_damage_buffer(ctx.shadow_wl_surface, 0, 0,
                                 ctx.shadow_dim[0], ctx.shadow_dim[1]);
        wl_subsurface_set_position(ctx.shadow_wl_subsurface, -SHADOW_MARGIN, -SHADOW_MARGIN);
        wl_surface_commit(ctx.shadow_wl_surface);
      }
    }
    
    /* window frame commit */
    if (!(ctx.control_flags & WindowControlFlag_Resize)){
      xdg_toplevel_set_min_size(ctx.main_xdg_toplevel, ctx.dim[0], ctx.dim[1]);
      xdg_toplevel_set_max_size(ctx.main_xdg_toplevel, ctx.dim[0], ctx.dim[1]);
    }
    else{
      for (int i = 0; i < 2; i += 1){
        int32_t mw = ClampBot(ctx.mmbox[0][i], csd_frame.minbox[i]) + csd_dim[0];
        int32_t mh = ctx.mmbox[1][i] + csd_dim[1];
        if (i == 0){
          xdg_toplevel_set_min_size(ctx.main_xdg_toplevel, mw, mh);
        }
        else{
          xdg_toplevel_set_max_size(ctx.main_xdg_toplevel, mw, mh);
        }
      }
    }
    
    xdg_surface_set_window_geometry(ctx.main_xdg_surface,
                                    -csd_frame.border[0][0],
                                    -csd_frame.border[1][0],
                                    ctx.dim[0] + csd_dim[0],
                                    ctx.dim[1] + csd_dim[1]);
    
    wl_egl_window_resize(ctx.main_wl_egl_window, ctx.dim[0], ctx.dim[1], 0, 0);
    
    /* app update & render */
    {
      if (ctx.close_signal){
        exit_loop = 1;
      }
      
      glDrawBuffer(GL_BACK);
      glViewport(0, 0, ctx.dim[0], ctx.dim[1]);
      glClearColor(0.40f, 0.90f, 0.15f, 1.f);
      glClear(GL_COLOR_BUFFER_BIT);
    }
    eglSwapBuffers(ctx.egl_display, ctx.main_egl_surface);
    wl_surface_commit(ctx.main_wl_surface);
    
    /* commit new cursor */
    {
      struct wl_cursor *cursor = ctx.wl_cursors[cursor_shape];
      if (cursor != 0){
        struct wl_cursor_image *cursor_image = cursor->images[0];
        struct wl_buffer *cursor_buffer = wl_cursor_image_get_buffer(cursor_image);
        wl_surface_set_buffer_scale(ctx.cursor_surface, 1);
        wl_surface_attach(ctx.cursor_surface, cursor_buffer, 0, 0);
        wl_surface_damage_buffer(ctx.cursor_surface, 0, 0,
                                 cursor_image->width, cursor_image->height);
        wl_surface_commit(ctx.cursor_surface);
        wl_pointer_set_cursor(ctx.wl_pointer, ctx.hover_serial, ctx.cursor_surface,
                              cursor_image->hotspot_x, cursor_image->hotspot_y);
      }
    }
    
  }
  
  return(0);
}

/* csd implementation */

static CSD_Frame
csd_impl_calculate_frame(void){
  CSD_Frame frame = {0};
  bool show_title = (!(ctx.config.flags & WindowFlag_IsFullscreen));
  if (show_title){
    for (int i = 0; i < 2; i += 1){
      for (int j = 0; j < 2; j += 1){
        frame.border[i][j] = SHADOW_MARGIN;
      }
    }
  }
  return(frame);
}

/* wayland helpers */

static WindowFlags
window_flags_from_states_array(struct wl_array *states){
  WindowFlags flags = 0;
  uint32_t *p;
  wl_array_for_each(p, states){
    switch (*p) {
      case XDG_TOPLEVEL_STATE_FULLSCREEN:   flags |= WindowFlag_IsFullscreen; break;
      case XDG_TOPLEVEL_STATE_MAXIMIZED:    flags |= WindowFlag_IsMax; break;
      case XDG_TOPLEVEL_STATE_ACTIVATED:    flags |= WindowFlag_IsActivated; break;
      case XDG_TOPLEVEL_STATE_TILED_LEFT:   flags |= WindowFlag_IsTiledLeft; break;
      case XDG_TOPLEVEL_STATE_TILED_RIGHT:  flags |= WindowFlag_IsTiledRight; break;
      case XDG_TOPLEVEL_STATE_TILED_TOP:    flags |= WindowFlag_IsTiledTop; break;
      case XDG_TOPLEVEL_STATE_TILED_BOTTOM: flags |= WindowFlag_IsTiledBottom; break;
      case XDG_TOPLEVEL_STATE_RESIZING:     flags |= WindowFlag_IsResizing; break;
      case XDG_TOPLEVEL_STATE_SUSPENDED:    flags |= WindowFlag_IsSuspended; break;
      case XDG_TOPLEVEL_STATE_CONSTRAINED_LEFT:   flags |= WindowFlag_IsConstrainedLeft; break;
      case XDG_TOPLEVEL_STATE_CONSTRAINED_RIGHT:  flags |= WindowFlag_IsConstrainedRight; break;
      case XDG_TOPLEVEL_STATE_CONSTRAINED_TOP:    flags |= WindowFlag_IsConstrainedTop; break;
      case XDG_TOPLEVEL_STATE_CONSTRAINED_BOTTOM: flags |= WindowFlag_IsConstrainedBottom; break;
      default: break;
    }
  }
  return(flags);
}

/* os */

static int
os_resize_anonymous_file(int fd, off_t size){
#ifdef HAVE_POSIX_FALLOCATE
  
  sigset_t mask;
  sigset_t old_mask;
  sigemptyset(&mask);
  sigaddset(&mask, SIGALRM);
  sigprocmask(SIG_BLOCK, &mask, &old_mask);
  
  do {
    errno = posix_fallocate(fd, 0, size);
  } while (errno == EINTR);
  sigprocmask(SIG_SETMASK, &old_mask, NULL);
  
  int result = 0;
  if (errno != 0){
    result = -1;
    if (errno == EINVAL || errno == EOPNOTSUPP){
      if (ftruncate(fd, size) >= 0){
        result = 0;
      }
    }
  }
  return(result);
  
#else
  
  int result = -1;
  if (ftruncate(fd, size) >= 0){
    result = 0;
  }
  return(result);
  
#endif
}

static int
os_create_anonymous_file(off_t size){
  static const char key[] = "/libdecor-shared-XXXXXX";
  int fd = -1;
  
#ifdef HAVE_MEMFD_CREATE
  fd = memfd_create("libdecor", MFD_CLOEXEC | MFD_ALLOW_SEALING);
  if (fd >= 0){
    fcntl(fd, F_ADD_SEALS, F_SEAL_SHRINK | F_SEAL_SEAL);
  }
#endif
  
  if (fd < 0){
    const char *path = getenv("XDG_RUNTIME_DIR");
    if (path == 0){
      errno = ENOENT;
    }
    else{
      char *name = malloc(strlen(path) + sizeof(key));
      if (name != 0){
        strcpy(name, path);
        strcat(name, key);
        
#ifdef HAVE_MKOSTEMP
        fd = mkostemp(name, O_CLOEXEC);
        if (fd >= 0){
          unlink(name);
        }
#else
        fd = mkstemp(name);
        
        if (fd >= 0){
          if (fcntl(fd, F_GETFD) == -1){
            close(fd);
            fd = -1;
          }
          else if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1){
            close(fd);
            fd = -1;
          }
        }
        
        if (fd >= 0) {
          unlink(name);
        }
#endif
        
        free(name);
      }
    }
  }
  
  if (fd >= 0 && os_resize_anonymous_file(fd, size) < 0){
    close(fd);
    fd = -1;
  }
  
  return(fd);
}

/* desktop settings */

static CursorTheme
ds__get_cursor_theme_from_env(void){
  CursorTheme result = {0};
  char *env_xtheme = getenv("XCURSOR_THEME");
  char *env_xsize = getenv("XCURSOR_SIZE");
  if (env_xtheme != 0 && env_xsize != 0){
    result.name = strdup(env_xtheme);
    result.size = atoi(env_xsize);
  }
  else{
    result.name = 0;
    result.size = 24;
  }
  return(result);
}

#ifdef HAS_DBUS
#include <dbus/dbus.h>

static DBusMessage *
ds__get_setting_sync(DBusConnection *const connection, const char *key1, const char *key2){
  DBusMessage *reply = 0;
  DBusMessage *message =
    dbus_message_new_method_call("org.freedesktop.portal.Desktop",
                                 "/org/freedesktop/portal/desktop",
                                 "org.freedesktop.portal.Settings",
                                 "Read");
  
  if (message != 0){
    dbus_bool_t success = dbus_message_append_args(message,
                                                   DBUS_TYPE_STRING, &key1,
                                                   DBUS_TYPE_STRING, &key2,
                                                   DBUS_TYPE_INVALID);
    if (success){
      DBusError error;
      dbus_error_init(&error);
      reply = dbus_connection_send_with_reply_and_block(connection, message, DBUS_TIMEOUT_USE_DEFAULT, &error);
      if (dbus_error_is_set(&error) && reply != 0){
        dbus_message_unref(reply);
        reply = 0;
      }
      dbus_error_free(&error);
    }
    dbus_message_unref(message);
  }
  
  return(reply);
}

static int
ds__parse_type(DBusMessage *const reply, const int type, void *value){
  int result = 0;
  DBusMessageIter iter[3];
  dbus_message_iter_init(reply, &iter[0]);
  if (dbus_message_iter_get_arg_type(&iter[0]) == DBUS_TYPE_VARIANT){
    dbus_message_iter_recurse(&iter[0], &iter[1]);
    if (dbus_message_iter_get_arg_type(&iter[1]) == DBUS_TYPE_VARIANT){
      dbus_message_iter_recurse(&iter[1], &iter[2]);
      if (dbus_message_iter_get_arg_type(&iter[2]) == type){
        dbus_message_iter_get_basic(&iter[2], value);
        result = 1;
      }
    }
  }
  return(result);
}

static CursorTheme
ds_get_cursor_theme(void){
  static const char key[] = "org.gnome.desktop.interface";
  static const char key_theme[] = "cursor-theme";
  static const char key_size[] = "cursor-size";
  
  char *name = 0;
  int size = 0;
  int success = 0;
  
  DBusError error;
  dbus_error_init(&error);
  DBusConnection *connection = dbus_bus_get(DBUS_BUS_SESSION, &error);
  
  if (!dbus_error_is_set(&error)){
    DBusMessage *reply = ds__get_setting_sync(connection, key, key_theme);
    if (reply != 0){
      if (!ds__parse_type(reply, DBUS_TYPE_STRING, &name)){
        name = 0;
      }
      dbus_message_unref(reply);
    }
  }
  
  if (name != 0){
    DBusMessage *reply = ds__get_setting_sync(connection, key, key_size);
    if (reply){
      if (ds__parse_type(reply, DBUS_TYPE_INT32, &size)){
        success = 1;
      }
      dbus_message_unref(reply);
    }
  }
  
  CursorTheme result = {0};
  if (success){
    result.name = name;
    result.size = size;
  }
  else{
    result = ds__get_cursor_theme_from_env();
  }
  
  return(result);
}

static ColorScheme
ds_get_color_scheme(){
  static const char name[] = "org.freedesktop.appearance";
  static const char key_color_scheme[] = "color-scheme";
  uint32_t color = 0;
  
  DBusError error;
  dbus_error_init(&error);
  DBusConnection *connection = dbus_bus_get(DBUS_BUS_SESSION, &error);
  
  if (!dbus_error_is_set(&error)){
    DBusMessage *reply = ds__get_setting_sync(connection, name, key_color_scheme);
    if (reply){
      if (!ds__parse_type(reply, DBUS_TYPE_UINT32, &color)) {
        color = 0;
      }
      dbus_message_unref(reply);
    }
  }
  return(color);
}

#else

static CursorTheme
ds_get_cursor_them(void){
  return(ds__get_cursor_theme_from_env());
}

static ColorScheme
ds_get_color_scheme(){
  return(ColorScheme_Default);
}

#endif