/*
Looking Glass - KVM FrameRelay (KVMFR) Client
Copyright (C) 2017-2019 Geoffrey McRae <geoff@hostfission.com>
https://looking-glass.hostfission.com

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include "app.h"

#include "main.h"
#include "core.h"
#include "util.h"
#include "clipboard.h"

#include "ll.h"
#include "kb.h"

#include "common/debug.h"
#include <stdarg.h>

void app_alert(LG_MsgAlert type, const char * fmt, ...)
{
  if (!g_state.lgr || !g_params.showAlerts)
    return;

  va_list args;
  va_start(args, fmt);
  const int length = vsnprintf(NULL, 0, fmt, args);
  va_end(args);

  char *buffer = malloc(length + 1);
  va_start(args, fmt);
  vsnprintf(buffer, length + 1, fmt, args);
  va_end(args);

  g_state.lgr->on_alert(
    g_state.lgrData,
    type,
    buffer,
    NULL
  );

  free(buffer);
}

KeybindHandle app_register_keybind(SDL_Scancode key, SuperEventFn callback, void * opaque)
{
  // don't allow duplicate binds
  if (g_state.bindings[key])
  {
    DEBUG_INFO("Key already bound");
    return NULL;
  }

  KeybindHandle handle = (KeybindHandle)malloc(sizeof(struct KeybindHandle));
  handle->key      = key;
  handle->callback = callback;
  handle->opaque   = opaque;

  g_state.bindings[key] = handle;
  return handle;
}

void app_release_keybind(KeybindHandle * handle)
{
  if (!*handle)
    return;

  g_state.bindings[(*handle)->key] = NULL;
  free(*handle);
  *handle = NULL;
}

bool app_getProp(LG_DSProperty prop, void * ret)
{
  return g_state.ds->getProp(prop, ret);
}

SDL_Window * app_getWindow(void)
{
  return g_state.window;
}

bool app_inputEnabled(void)
{
  return g_params.useSpiceInput && !g_state.ignoreInput &&
    ((g_cursor.grab && g_params.captureInputOnly) || !g_params.captureInputOnly);
}

bool app_cursorInWindow(void)
{
  return g_cursor.inWindow;
}

bool app_cursorIsGrabbed(void)
{
  return g_cursor.grab;
}

bool app_cursorWantsRaw(void)
{
  return g_params.rawMouse;
}

void app_updateCursorPos(double x, double y)
{
  g_cursor.pos.x = x;
  g_cursor.pos.y = y;
  g_cursor.valid = true;
}

void app_handleFocusEvent(bool focused)
{
  g_state.focused = focused;
  if (!app_inputEnabled())
    return;

  if (!focused)
  {
    core_setGrabQuiet(false);
    core_setCursorInView(false);
  }

  g_cursor.realign = true;
  g_state.ds->realignPointer();
}

void app_handleEnterEvent(bool entered)
{
  if (entered)
  {
    g_cursor.inWindow = true;
    if (!app_inputEnabled())
      return;

    g_cursor.realign = true;
  }
  else
  {
    g_cursor.inWindow = false;
    core_setCursorInView(false);

    if (!app_inputEnabled())
      return;

    if (!g_params.alwaysShowCursor)
      g_cursor.draw = false;
    g_cursor.redraw = true;
  }
}

void app_clipboardRelease(void)
{
  if (!g_params.clipboardToVM)
    return;

  spice_clipboard_release();
}

void app_clipboardNotify(const LG_ClipboardData type, size_t size)
{
  if (!g_params.clipboardToVM)
    return;

  if (type == LG_CLIPBOARD_DATA_NONE)
  {
    spice_clipboard_release();
    return;
  }

  g_state.cbType    = cb_lgTypeToSpiceType(type);
  g_state.cbChunked = size > 0;
  g_state.cbXfer    = size;

  spice_clipboard_grab(g_state.cbType);

  if (size)
    spice_clipboard_data_start(g_state.cbType, size);
}

void app_clipboardData(const LG_ClipboardData type, uint8_t * data, size_t size)
{
  if (!g_params.clipboardToVM)
    return;

  if (g_state.cbChunked && size > g_state.cbXfer)
  {
    DEBUG_ERROR("refusing to send more then cbXfer bytes for chunked xfer");
    size = g_state.cbXfer;
  }

  if (!g_state.cbChunked)
    spice_clipboard_data_start(g_state.cbType, size);

  spice_clipboard_data(g_state.cbType, data, (uint32_t)size);
  g_state.cbXfer -= size;
}

void app_clipboardRequest(const LG_ClipboardReplyFn replyFn, void * opaque)
{
  if (!g_params.clipboardToLocal)
    return;

  struct CBRequest * cbr = (struct CBRequest *)malloc(sizeof(struct CBRequest));

  cbr->type    = g_state.cbType;
  cbr->replyFn = replyFn;
  cbr->opaque  = opaque;
  ll_push(g_state.cbRequestList, cbr);

  spice_clipboard_request(g_state.cbType);
}

void spiceClipboardNotice(const SpiceDataType type)
{
  if (!g_params.clipboardToLocal)
    return;

  if (!g_state.cbAvailable)
    return;

  g_state.cbType = type;
  g_state.ds->cbNotice(cb_spiceTypeToLGType(type));
}

void app_handleMouseGrabbed(double ex, double ey)
{
  if (!app_inputEnabled())
    return;

  int x, y;
  if (g_params.rawMouse && !g_cursor.useScale)
  {
    /* raw unscaled input are always round numbers */
    x = floor(ex);
    y = floor(ey);
  }
  else
  {
    /* apply sensitivity */
    ex = (ex / 10.0) * (g_cursor.sens + 10);
    ey = (ey / 10.0) * (g_cursor.sens + 10);
    util_cursorToInt(ex, ey, &x, &y);
  }

  if (x == 0 && y == 0)
    return;

  if (!spice_mouse_motion(x, y))
    DEBUG_ERROR("failed to send mouse motion message");
}

void app_handleButtonPress(int button)
{
  if (!app_inputEnabled() || !g_cursor.inView)
    return;

  g_cursor.buttons |= (1U << button);

  if (!spice_mouse_press(button))
    DEBUG_ERROR("SDL_MOUSEBUTTONDOWN: failed to send message");
}

void app_handleButtonRelease(int button)
{
  if (!app_inputEnabled())
    return;

  g_cursor.buttons &= ~(1U << button);

  if (!spice_mouse_release(button))
    DEBUG_ERROR("SDL_MOUSEBUTTONUP: failed to send message");
}

void app_handleKeyPress(int sc)
{
  if (sc == g_params.escapeKey && !g_state.escapeActive)
  {
    g_state.escapeActive = true;
    g_state.escapeAction = -1;
    return;
  }

  if (g_state.escapeActive)
  {
    g_state.escapeAction = sc;
    return;
  }

  if (!app_inputEnabled())
    return;

  if (g_params.ignoreWindowsKeys && (sc == KEY_LEFTMETA || sc == KEY_RIGHTMETA))
    return;

  if (!g_state.keyDown[sc])
  {
    uint32_t ps2 = xfree86_to_ps2[sc];
    if (!ps2)
      return;

    if (spice_key_down(ps2))
      g_state.keyDown[sc] = true;
    else
    {
      DEBUG_ERROR("SDL_KEYDOWN: failed to send message");
      return;
    }
  }
}

void app_handleKeyRelease(int sc)
{
  if (g_state.escapeActive)
  {
    if (g_state.escapeAction == -1)
    {
      if (g_params.useSpiceInput)
        core_setGrab(!g_cursor.grab);
    }
    else
    {
      KeybindHandle handle = g_state.bindings[sc];
      if (handle)
      {
        handle->callback(sc, handle->opaque);
        return;
      }
    }

    if (sc == g_params.escapeKey)
      g_state.escapeActive = false;
  }

  if (!app_inputEnabled())
    return;

  // avoid sending key up events when we didn't send a down
  if (!g_state.keyDown[sc])
    return;

  if (g_params.ignoreWindowsKeys && (sc == KEY_LEFTMETA || sc == KEY_RIGHTMETA))
    return;

  uint32_t ps2 = xfree86_to_ps2[sc];
  if (!ps2)
    return;

  if (spice_key_up(ps2))
    g_state.keyDown[sc] = false;
  else
  {
    DEBUG_ERROR("SDL_KEYUP: failed to send message");
    return;
  }
}

void app_handleMouseNormal(double ex, double ey)
{
  // prevent cursor handling outside of capture if the position is not known
  if (!g_cursor.guest.valid)
    return;

  if (!app_inputEnabled())
    return;

  /* scale the movement to the guest */
  if (g_cursor.useScale && g_params.scaleMouseInput)
  {
    ex *= g_cursor.scale.x / g_cursor.dpiScale;
    ey *= g_cursor.scale.y / g_cursor.dpiScale;
  }

  bool testExit = true;
  if (!g_cursor.inView)
  {
    const bool inView =
      g_cursor.pos.x >= g_state.dstRect.x                     &&
      g_cursor.pos.x <  g_state.dstRect.x + g_state.dstRect.w &&
      g_cursor.pos.y >= g_state.dstRect.y                     &&
      g_cursor.pos.y <  g_state.dstRect.y + g_state.dstRect.h;

    core_setCursorInView(inView);
    if (inView)
      g_cursor.realign = true;
  }

  /* nothing to do if we are outside the viewport */
  if (!g_cursor.inView)
    return;

  /*
   * do not pass mouse events to the guest if we do not have focus, this must be
   * done after the inView test has been performed so that when focus is gained
   * we know if we should be drawing the cursor.
   */
  if (!g_state.focused)
    return;

  /* if we have been instructed to realign */
  if (g_cursor.realign)
  {
    g_cursor.realign = false;

    struct DoublePoint guest;
    util_localCurToGuest(&guest);

    /* add the difference to the offset */
    ex += guest.x - (g_cursor.guest.x + g_cursor.guest.hx);
    ey += guest.y - (g_cursor.guest.y + g_cursor.guest.hy);

    /* don't test for an exit as we just entered, we can get into a enter/exit
     * loop otherwise */
    testExit = false;
  }

  /* if we are in "autoCapture" and the delta was large don't test for exit */
  if (g_params.autoCapture &&
      (fabs(ex) > 100.0 / g_cursor.scale.x || fabs(ey) > 100.0 / g_cursor.scale.y))
    testExit = false;

  /* if any buttons are held we should not allow exit to happen */
  if (g_cursor.buttons)
    testExit = false;

  if (testExit)
  {
    /* translate the move to the guests orientation */
    struct DoublePoint move = {.x = ex, .y = ey};
    util_rotatePoint(&move);

    /* translate the guests position to our coordinate space */
    struct DoublePoint local;
    util_guestCurToLocal(&local);

    /* check if the move would push the cursor outside the guest's viewport */
    if (
        local.x + move.x <  g_state.dstRect.x ||
        local.y + move.y <  g_state.dstRect.y ||
        local.x + move.x >= g_state.dstRect.x + g_state.dstRect.w ||
        local.y + move.y >= g_state.dstRect.y + g_state.dstRect.h)
    {
      local.x += move.x;
      local.y += move.y;
      const int tx = (local.x <= 0.0) ? floor(local.x) : ceil(local.x);
      const int ty = (local.y <= 0.0) ? floor(local.y) : ceil(local.y);

      if (core_isValidPointerPos(
            g_state.windowPos.x + g_state.border.left + tx,
            g_state.windowPos.y + g_state.border.top  + ty))
      {
        core_setCursorInView(false);

        /* preempt the window leave flag if the warp will leave our window */
        if (tx < 0 || ty < 0 || tx > g_state.windowW || ty > g_state.windowH)
          g_cursor.inWindow = false;

        /* ungrab the pointer and move the local cursor to the exit point */
        g_state.ds->ungrabPointer();
        core_warpPointer(tx, ty, true);
        return;
      }
    }
  }

  int x, y;
  util_cursorToInt(ex, ey, &x, &y);

  if (x == 0 && y == 0)
    return;

  if (g_params.autoCapture)
  {
    g_cursor.delta.x += x;
    g_cursor.delta.y += y;

    if (fabs(g_cursor.delta.x) > 50.0 || fabs(g_cursor.delta.y) > 50.0)
    {
      g_cursor.delta.x = 0;
      g_cursor.delta.y = 0;
      core_warpPointer(g_state.windowCX, g_state.windowCY, false);
    }

    g_cursor.guest.x = g_state.srcSize.x / 2;
    g_cursor.guest.y = g_state.srcSize.y / 2;
  }
  else
  {
    /* assume the mouse will move to the location we attempt to move it to so we
     * avoid warp out of window issues. The cursorThread will correct this if
     * wrong after the movement has ocurred on the guest */
    g_cursor.guest.x += x;
    g_cursor.guest.y += y;
  }

  if (!spice_mouse_motion(x, y))
    DEBUG_ERROR("failed to send mouse motion message");
}


// On some display servers normal cursor logic does not work due to the lack of
// cursor warp support. Instead, we attempt a best-effort emulation which works
// with a 1:1 mouse movement patch applied in the guest. For anything fancy, use
// capture mode.
void app_handleMouseBasic()
{
  /* do not pass mouse events to the guest if we do not have focus */
  if (!g_state.focused)
    return;

  if (!app_inputEnabled())
    return;

  const bool inView =
    g_cursor.pos.x >= g_state.dstRect.x                     &&
    g_cursor.pos.x <  g_state.dstRect.x + g_state.dstRect.w &&
    g_cursor.pos.y >= g_state.dstRect.y                     &&
    g_cursor.pos.y <  g_state.dstRect.y + g_state.dstRect.h;

  core_setCursorInView(inView);

  if (g_cursor.guest.dpiScale == 0)
    return;

  double px = g_cursor.pos.x;
  double py = g_cursor.pos.y;

  if (px < g_state.dstRect.x)
    px = g_state.dstRect.x;
  else if (px > g_state.dstRect.x + g_state.dstRect.w)
    px = g_state.dstRect.x + g_state.dstRect.w;

  if (py < g_state.dstRect.y)
    py = g_state.dstRect.y;
  else if (py > g_state.dstRect.y + g_state.dstRect.h)
    py = g_state.dstRect.y + g_state.dstRect.h;

  /* translate the guests position to our coordinate space */
  struct DoublePoint local;
  util_guestCurToLocal(&local);

  int x = (int) round((px - local.x) / g_cursor.dpiScale);
  int y = (int) round((py - local.y) / g_cursor.dpiScale);

  if (!x && !y)
    return;

  g_cursor.guest.x += x;
  g_cursor.guest.y += y;

  if (!spice_mouse_motion(x, y))
    DEBUG_ERROR("failed to send mouse motion message");
}

void app_updateWindowPos(int x, int y)
{
  g_state.windowPos.x = x;
  g_state.windowPos.y = y;
}

void app_handleResizeEvent(int w, int h, const struct Border border)
{
  memcpy(&g_state.border, &border, sizeof(border));

  /* don't do anything else if the window dimensions have not changed */
  if (g_state.windowW == w && g_state.windowH == h)
    return;

  g_state.windowW  = w;
  g_state.windowH  = h;
  g_state.windowCX = w / 2;
  g_state.windowCY = h / 2;
  core_updatePositionInfo();

  if (app_inputEnabled())
  {
    /* if the window is moved/resized causing a loss of focus while grabbed, it
     * makes it impossible to re-focus the window, so we quietly re-enter
     * capture if we were already in it */
    if (g_cursor.grab)
    {
      core_setGrabQuiet(false);
      core_setGrabQuiet(true);
    }
    core_alignToGuest();
  }
}

void app_handleCloseEvent(void)
{
  if (!g_params.ignoreQuit || !g_cursor.inView)
    g_state.state = APP_STATE_SHUTDOWN;
}