/* Haiku window system selection support.
   Copyright (C) 2021-2022 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs 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 3 of the License, or (at
your option) any later version.

GNU Emacs 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 GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include "lisp.h"
#include "blockinput.h"
#include "coding.h"
#include "haikuselect.h"
#include "haikuterm.h"
#include "haiku_support.h"

#include <stdlib.h>

/* The frame that is currently the source of a drag-and-drop
   operation, or NULL if none is in progress.  The reason for this
   variable is to prevent it from being deleted, which really breaks
   the nested event loop inside be_drag_message.  */
struct frame *haiku_dnd_frame;

static void haiku_lisp_to_message (Lisp_Object, void *);

DEFUN ("haiku-selection-data", Fhaiku_selection_data, Shaiku_selection_data,
       2, 2, 0,
       doc: /* Retrieve content typed as NAME from the clipboard
CLIPBOARD.  CLIPBOARD is the symbol `PRIMARY', `SECONDARY' or
`CLIPBOARD'.  NAME is a string describing the MIME type denoting the
type of the data to fetch.  If NAME is nil, then the entire contents
of the clipboard will be returned instead, as a serialized system
message in the format accepted by `haiku-drag-message', which see.  */)
  (Lisp_Object clipboard, Lisp_Object name)
{
  char *dat;
  ssize_t len;
  Lisp_Object str;
  void *message;
  enum haiku_clipboard clipboard_name;
  int rc;

  CHECK_SYMBOL (clipboard);

  if (!EQ (clipboard, QPRIMARY) && !EQ (clipboard, QSECONDARY)
      && !EQ (clipboard, QCLIPBOARD))
    signal_error ("Invalid clipboard", clipboard);

  if (!NILP (name))
    {
      CHECK_STRING (name);

      block_input ();
      if (EQ (clipboard, QPRIMARY))
	dat = BClipboard_find_primary_selection_data (SSDATA (name), &len);
      else if (EQ (clipboard, QSECONDARY))
	dat = BClipboard_find_secondary_selection_data (SSDATA (name), &len);
      else
	dat = BClipboard_find_system_data (SSDATA (name), &len);
      unblock_input ();

      if (!dat)
	return Qnil;

      str = make_unibyte_string (dat, len);

      /* `foreign-selection' just means that the selection has to be
	 decoded by `gui-get-selection'.  It has no other meaning,
	 AFAICT.  */
      Fput_text_property (make_fixnum (0), make_fixnum (len),
			  Qforeign_selection, Qt, str);

      block_input ();
      BClipboard_free_data (dat);
      unblock_input ();
    }
  else
    {
      if (EQ (clipboard, QPRIMARY))
	clipboard_name = CLIPBOARD_PRIMARY;
      else if (EQ (clipboard, QSECONDARY))
	clipboard_name = CLIPBOARD_SECONDARY;
      else
	clipboard_name = CLIPBOARD_CLIPBOARD;

      block_input ();
      rc = be_lock_clipboard_message (clipboard_name, &message, false);
      unblock_input ();

      if (rc)
	signal_error ("Couldn't open clipboard", clipboard);

      block_input ();
      str = haiku_message_to_lisp (message);
      be_unlock_clipboard (clipboard_name, true);
      unblock_input ();
    }

  return str;
}

static void
haiku_unwind_clipboard_lock (int clipboard)
{
  be_unlock_clipboard (clipboard, false);
}

DEFUN ("haiku-selection-put", Fhaiku_selection_put, Shaiku_selection_put,
       2, 4, 0,
       doc: /* Add or remove content from the clipboard CLIPBOARD.
CLIPBOARD is the symbol `PRIMARY', `SECONDARY' or `CLIPBOARD'.  NAME
is a MIME type denoting the type of the data to add.  DATA is the
string that will be placed in the clipboard, or nil if the content is
to be removed.  CLEAR, if non-nil, means to erase all the previous
contents of the clipboard.

Alternatively, NAME can be a system message in the format accepted by
`haiku-drag-message', which will replace the contents of CLIPBOARD.
In that case, the arguments after NAME are ignored.  */)
  (Lisp_Object clipboard, Lisp_Object name, Lisp_Object data,
   Lisp_Object clear)
{
  enum haiku_clipboard clipboard_name;
  specpdl_ref ref;
  char *dat;
  ptrdiff_t len;
  int rc;
  void *message;

  if (CONSP (name) || NILP (name))
    {
      if (EQ (clipboard, QPRIMARY))
	clipboard_name = CLIPBOARD_PRIMARY;
      else if (EQ (clipboard, QSECONDARY))
	clipboard_name = CLIPBOARD_SECONDARY;
      else if (EQ (clipboard, QCLIPBOARD))
	clipboard_name = CLIPBOARD_CLIPBOARD;
      else
	signal_error ("Invalid clipboard", clipboard);

      rc = be_lock_clipboard_message (clipboard_name,
				      &message, true);

      if (rc)
	signal_error ("Couldn't open clipboard", clipboard);

      ref = SPECPDL_INDEX ();
      record_unwind_protect_int (haiku_unwind_clipboard_lock,
				 clipboard_name);
      haiku_lisp_to_message (name, message);

      return unbind_to (ref, Qnil);
    }

  CHECK_SYMBOL (clipboard);
  CHECK_STRING (name);
  if (!NILP (data))
    CHECK_STRING (data);

  dat = !NILP (data) ? SSDATA (data) : NULL;
  len = !NILP (data) ? SBYTES (data) : 0;

  if (EQ (clipboard, QPRIMARY))
    BClipboard_set_primary_selection_data (SSDATA (name), dat, len,
					   !NILP (clear));
  else if (EQ (clipboard, QSECONDARY))
    BClipboard_set_secondary_selection_data (SSDATA (name), dat, len,
					     !NILP (clear));
  else if (EQ (clipboard, QCLIPBOARD))
    BClipboard_set_system_data (SSDATA (name), dat, len, !NILP (clear));
  else
    {
      unblock_input ();
      signal_error ("Bad clipboard", clipboard);
    }

  return Qnil;
}

DEFUN ("haiku-selection-owner-p", Fhaiku_selection_owner_p, Shaiku_selection_owner_p,
       0, 1, 0,
       doc: /* Whether the current Emacs process owns the given SELECTION.
The arg should be the name of the selection in question, typically one
of the symbols `PRIMARY', `SECONDARY', or `CLIPBOARD'.  For
convenience, the symbol nil is the same as `PRIMARY', and t is the
same as `SECONDARY'.  */)
  (Lisp_Object selection)
{
  bool value;

  if (NILP (selection))
    selection = QPRIMARY;
  else if (EQ (selection, Qt))
    selection = QSECONDARY;

  block_input ();
  if (EQ (selection, QPRIMARY))
    value = BClipboard_owns_primary ();
  else if (EQ (selection, QSECONDARY))
    value = BClipboard_owns_secondary ();
  else if (EQ (selection, QCLIPBOARD))
    value = BClipboard_owns_clipboard ();
  else
    value = false;
  unblock_input ();

  return value ? Qt : Qnil;
}

/* Return the Lisp representation of MESSAGE.  See Fhaiku_drag_message
   for the format of the object returned.  */
Lisp_Object
haiku_message_to_lisp (void *message)
{
  Lisp_Object list = Qnil, tem, t1, t2;
  const char *name;
  char *pbuf;
  const void *buf;
  ssize_t buf_size;
  int32 i, j, count, type_code;
  int rc;
  void *msg;
  float point_x, point_y;

  for (i = 0; !be_enum_message (message, &type_code, i,
				&count, &name); ++i)
    {
      tem = Qnil;

      for (j = 0; j < count; ++j)
	{
	  rc = be_get_message_data (message, name,
				    type_code, j,
				    &buf, &buf_size);
	  if (rc)
	    emacs_abort ();

	  switch (type_code)
	    {
	    case 'MSGG':
	      msg = be_get_message_message (message, name, j);
	      if (!msg)
		memory_full (SIZE_MAX);
	      t1 = haiku_message_to_lisp (msg);
	      BMessage_delete (msg);

	      break;

	    case 'BOOL':
	      t1 = (*(bool *) buf) ? Qt : Qnil;
	      break;

	    case 'RREF':
	      rc = be_get_refs_data (message, name,
				     j, &pbuf);

	      if (rc)
		{
		  t1 = Qnil;
		  break;
		}

	      if (!pbuf)
		memory_full (SIZE_MAX);

	      t1 = build_string (pbuf);

	      free (pbuf);
	      break;

	    case 'BPNT':
	      rc = be_get_point_data (message, name,
				      j, &point_x,
				      &point_y);

	      if (rc)
		{
		  t1 = Qnil;
		  break;
		}

	      t1 = Fcons (make_float (point_x),
			  make_float (point_y));
	      break;

	    case 'SHRT':
	      t1 = make_fixnum (*(int16 *) buf);
	      break;

	    case 'LONG':
	      t1 = make_int (*(int32 *) buf);
	      break;

	    case 'LLNG':
	      t1 = make_int ((intmax_t) *(int64 *) buf);
	      break;

	    case 'BYTE':
	    case 'CHAR':
	      t1 = make_fixnum (*(int8 *) buf);
	      break;

	    case 'SIZT':
	      t1 = make_uint ((uintmax_t) *(size_t *) buf);
	      break;

	    case 'SSZT':
	      t1 = make_int ((intmax_t) *(ssize_t *) buf);
	      break;

	    default:
	      t1 = make_uninit_string (buf_size);
	      memcpy (SDATA (t1), buf, buf_size);
	    }

	  tem = Fcons (t1, tem);
	}

      switch (type_code)
	{
	case 'CSTR':
	  t2 = Qstring;
	  break;

	case 'SHRT':
	  t2 = Qshort;
	  break;

	case 'LONG':
	  t2 = Qlong;
	  break;

	case 'LLNG':
	  t2 = Qllong;
	  break;

	case 'BYTE':
	  t2 = Qbyte;
	  break;

	case 'RREF':
	  t2 = Qref;
	  break;

	case 'CHAR':
	  t2 = Qchar;
	  break;

	case 'BOOL':
	  t2 = Qbool;
	  break;

	case 'MSGG':
	  t2 = Qmessage;
	  break;

	case 'SIZT':
	  t2 = Qsize_t;
	  break;

	case 'SSZT':
	  t2 = Qssize_t;
	  break;

	case 'BPNT':
	  t2 = Qpoint;
	  break;

	default:
	  t2 = make_int (type_code);
	}

      tem = Fcons (t2, tem);
      list = Fcons (Fcons (build_string_from_utf8 (name), tem), list);
    }

  tem = Fcons (Qtype, make_uint (be_get_message_type (message)));
  return Fcons (tem, list);
}

static int32
lisp_to_type_code (Lisp_Object obj)
{
  if (BIGNUMP (obj))
    return (int32) bignum_to_intmax (obj);

  if (FIXNUMP (obj))
    return XFIXNUM (obj);

  if (EQ (obj, Qstring))
    return 'CSTR';
  else if (EQ (obj, Qshort))
    return 'SHRT';
  else if (EQ (obj, Qlong))
    return 'LONG';
  else if (EQ (obj, Qllong))
    return 'LLNG';
  else if (EQ (obj, Qbyte))
    return 'BYTE';
  else if (EQ (obj, Qref))
    return 'RREF';
  else if (EQ (obj, Qchar))
    return 'CHAR';
  else if (EQ (obj, Qbool))
    return 'BOOL';
  else if (EQ (obj, Qmessage))
    return 'MSGG';
  else if (EQ (obj, Qsize_t))
    return 'SIZT';
  else if (EQ (obj, Qssize_t))
    return 'SSZT';
  else if (EQ (obj, Qpoint))
    return 'BPNT';
  else
    return -1;
}

static void
haiku_lisp_to_message (Lisp_Object obj, void *message)
{
  Lisp_Object tem, t1, name, type_sym, t2, data;
  int32 type_code, long_data;
  int16 short_data;
  int64 llong_data;
  int8 char_data;
  bool bool_data;
  void *msg_data;
  size_t sizet_data;
  ssize_t ssizet_data;
  intmax_t t4;
  uintmax_t t5;
  float t6, t7;
  int rc;
  specpdl_ref ref;

  CHECK_LIST (obj);
  for (tem = obj; CONSP (tem); tem = XCDR (tem))
    {
      maybe_quit ();
      t1 = XCAR (tem);
      CHECK_CONS (t1);

      name = XCAR (t1);

      if (EQ (name, Qtype))
	{
	  t2 = XCDR (t1);

	  if (BIGNUMP (t2))
	    {
	      t5 = bignum_to_uintmax (t2);

	      if (!t5 || t5 > TYPE_MAXIMUM (uint32))
		signal_error ("Value too large", t2);

	      block_input ();
	      be_set_message_type (message, t5);
	      unblock_input ();
	    }
	  else
	    {
	      if (!TYPE_RANGED_FIXNUMP (uint32, t2))
		signal_error ("Invalid data type", t2);

	      block_input ();
	      be_set_message_type (message, XFIXNAT (t2));
	      unblock_input ();
	    }

	  continue;
	}

      CHECK_STRING (name);

      t1 = XCDR (t1);
      CHECK_CONS (t1);

      type_sym = XCAR (t1);
      type_code = lisp_to_type_code (type_sym);

      if (type_code == -1)
	signal_error ("Unknown data type", type_sym);

      CHECK_LIST (t1);
      for (t2 = XCDR (t1); CONSP (t2); t2 = XCDR (t2))
	{
	  maybe_quit ();
	  data = XCAR (t2);

	  if (FIXNUMP (type_sym) || BIGNUMP (type_sym))
	    goto decode_normally;

	  switch (type_code)
	    {
	    case 'MSGG':
	      ref = SPECPDL_INDEX ();

	      block_input ();
	      msg_data = be_create_simple_message ();
	      unblock_input ();

	      record_unwind_protect_ptr (BMessage_delete, msg_data);
	      haiku_lisp_to_message (data, msg_data);

	      block_input ();
	      rc = be_add_message_message (message, SSDATA (name), msg_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Invalid message", msg_data);
	      unbind_to (ref, Qnil);
	      break;

	    case 'RREF':
	      CHECK_STRING (data);

	      if (be_add_refs_data (message, SSDATA (name), SSDATA (data))
		  && haiku_signal_invalid_refs)
		signal_error ("Invalid file name", data);
	      break;

	    case 'BPNT':
	      CHECK_CONS (data);
	      CHECK_NUMBER (XCAR (data));
	      CHECK_NUMBER (XCDR (data));

	      t6 = XFLOATINT (XCAR (data));
	      t7 = XFLOATINT (XCDR (data));

	      if (be_add_point_data (message, SSDATA (name),
				     t6, t7))
		signal_error ("Invalid point", data);
	      break;

	    case 'SHRT':
	      if (!TYPE_RANGED_FIXNUMP (int16, data))
		signal_error ("Invalid value", data);
	      short_data = XFIXNUM (data);

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &short_data,
					sizeof short_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add short", data);
	      break;

	    case 'LONG':
	      if (BIGNUMP (data))
		{
		  t4 = bignum_to_intmax (data);

		  /* We know that int32 is signed.  */
		  if (!t4 || t4 > TYPE_MINIMUM (int32)
		      || t4 < TYPE_MAXIMUM (int32))
		    signal_error ("Value too large", data);

		  long_data = (int32) t4;
		}
	      else
		{
		  if (!TYPE_RANGED_FIXNUMP (int32, data))
		    signal_error ("Invalid value", data);

		  long_data = (int32) XFIXNUM (data);
		}

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &long_data,
					sizeof long_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add long", data);
	      break;

	    case 'LLNG':
	      if (BIGNUMP (data))
		{
		  t4 = bignum_to_intmax (data);

		  if (!t4 || t4 > TYPE_MINIMUM (int64)
		      || t4 < TYPE_MAXIMUM (int64))
		    signal_error ("Value too large", data);

		  llong_data = (int64) t4;
		}
	      else
		{
		  if (!TYPE_RANGED_FIXNUMP (int64, data))
		    signal_error ("Invalid value", data);

		  llong_data = (int64) XFIXNUM (data);
		}

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &llong_data,
					sizeof llong_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add llong", data);
	      break;

	    case 'SIZT':
	      if (BIGNUMP (data))
		{
		  t4 = bignum_to_intmax (data);

		  if (!t4 || t4 > TYPE_MAXIMUM (size_t))
		    signal_error ("Value too large", data);

		  sizet_data = (size_t) t4;
		}
	      else
		{
		  if (!TYPE_RANGED_FIXNUMP (size_t, data))
		    signal_error ("Invalid value", data);

		  sizet_data = (int64) XFIXNUM (data);
		}

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &sizet_data,
					sizeof sizet_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add sizet", data);
	      break;

	    case 'SSZT':
	      if (BIGNUMP (data))
		{
		  t4 = bignum_to_intmax (data);

		  if (!t4 || t4 > TYPE_MINIMUM (ssize_t)
		      || t4 < TYPE_MAXIMUM (ssize_t))
		    signal_error ("Value too large", data);

		  ssizet_data = (ssize_t) t4;
		}
	      else
		{
		  if (!TYPE_RANGED_FIXNUMP (ssize_t, data))
		    signal_error ("Invalid value", data);

		  ssizet_data = (int64) XFIXNUM (data);
		}

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &ssizet_data,
					sizeof ssizet_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add ssizet", data);
	      break;

	    case 'CHAR':
	    case 'BYTE':
	      if (!TYPE_RANGED_FIXNUMP (int8, data))
		signal_error ("Invalid value", data);
	      char_data = XFIXNUM (data);

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &char_data,
					sizeof char_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add char", data);
	      break;

	    case 'BOOL':
	      bool_data = !NILP (data);

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, &bool_data,
					sizeof bool_data);
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add bool", data);
	      break;

	    default:
	    decode_normally:
	      CHECK_STRING (data);

	      block_input ();
	      rc = be_add_message_data (message, SSDATA (name),
					type_code, SDATA (data),
					SBYTES (data));
	      unblock_input ();

	      if (rc)
		signal_error ("Failed to add", data);
	    }
	}
      CHECK_LIST_END (t2, t1);
    }
  CHECK_LIST_END (tem, obj);
}

static bool
haiku_should_quit_drag (void)
{
  return !NILP (Vquit_flag);
}

static void
haiku_unwind_drag_message (void *message)
{
  haiku_dnd_frame = NULL;
  BMessage_delete (message);
}

DEFUN ("haiku-drag-message", Fhaiku_drag_message, Shaiku_drag_message,
       2, 3, 0,
       doc: /* Begin dragging MESSAGE from FRAME.

MESSAGE an alist of strings, denoting message field names, to a list
the form (TYPE DATA ...), where TYPE is an integer denoting the system
data type of DATA, and DATA is in the general case a unibyte string.

If TYPE is a symbol instead of an integer, then DATA was specially
decoded.  If TYPE is `ref', then DATA is the absolute file name of a
file, or nil if decoding the file name failed.  If TYPE is `string',
then DATA is a unibyte string.  If TYPE is `short', then DATA is a
16-bit signed integer.  If TYPE is `long', then DATA is a 32-bit
signed integer.  If TYPE is `llong', then DATA is a 64-bit signed
integer. If TYPE is `byte' or `char', then DATA is an 8-bit signed
integer.  If TYPE is `bool', then DATA is a boolean.  If TYPE is
`size_t', then DATA is an integer that can hold between 0 and the
maximum value returned by the `sizeof' C operator on the current
system.  If TYPE is `ssize_t', then DATA is an integer that can hold
values from -1 to the maximum value of the C data type `ssize_t' on
the current system.  If TYPE is `point', then DATA is a cons of float
values describing the X and Y coordinates of an on-screen location.

If the field name is not a string but the symbol `type', then it
associates to a 32-bit unsigned integer describing the type of the
system message.

FRAME is a window system frame that must be visible, from which the
drag will originate.

ALLOW-SAME-FRAME, if nil or not specified, means that MESSAGE will be
ignored if it is dropped on top of FRAME.  */)
  (Lisp_Object frame, Lisp_Object message, Lisp_Object allow_same_frame)
{
  specpdl_ref idx;
  void *be_message;
  struct frame *f;
  bool rc;

  idx = SPECPDL_INDEX ();
  f = decode_window_system_frame (frame);

  if (!FRAME_VISIBLE_P (f))
    error ("Frame is invisible");

  haiku_dnd_frame = f;
  be_message = be_create_simple_message ();

  record_unwind_protect_ptr (haiku_unwind_drag_message, be_message);
  haiku_lisp_to_message (message, be_message);
  rc = be_drag_message (FRAME_HAIKU_VIEW (f), be_message,
			!NILP (allow_same_frame),
			block_input, unblock_input,
			process_pending_signals,
			haiku_should_quit_drag);
  FRAME_DISPLAY_INFO (f)->grabbed = 0;

  if (rc)
    quit ();

  return unbind_to (idx, Qnil);
}

static Lisp_Object
haiku_note_drag_motion_1 (void *data)
{
  if (!NILP (Vhaiku_drag_track_function))
    return call0 (Vhaiku_drag_track_function);

  return Qnil;
}

static Lisp_Object
haiku_note_drag_motion_2 (enum nonlocal_exit exit, Lisp_Object error)
{
  return Qnil;
}

void
haiku_note_drag_motion (void)
{
  internal_catch_all (haiku_note_drag_motion_1, NULL,
		      haiku_note_drag_motion_2);
}

void
syms_of_haikuselect (void)
{
  DEFVAR_BOOL ("haiku-signal-invalid-refs", haiku_signal_invalid_refs,
     doc: /* If nil, silently ignore invalid file names in system messages.
Otherwise, an error will be signalled if adding a file reference to a
system message failed.  */);
  haiku_signal_invalid_refs = true;

  DEFVAR_LISP ("haiku-drag-track-function", Vhaiku_drag_track_function,
     doc: /* If non-nil, a function to call upon mouse movement while dragging a message.
The function is called without any arguments.  `mouse-position' can be
used to retrieve the current position of the mouse.  */);
  Vhaiku_drag_track_function = Qnil;

  DEFSYM (QSECONDARY, "SECONDARY");
  DEFSYM (QCLIPBOARD, "CLIPBOARD");
  DEFSYM (QSTRING, "STRING");
  DEFSYM (QUTF8_STRING, "UTF8_STRING");
  DEFSYM (Qforeign_selection, "foreign-selection");
  DEFSYM (QTARGETS, "TARGETS");
  DEFSYM (Qmessage, "message");
  DEFSYM (Qstring, "string");
  DEFSYM (Qref, "ref");
  DEFSYM (Qshort, "short");
  DEFSYM (Qlong, "long");
  DEFSYM (Qllong, "llong");
  DEFSYM (Qbyte, "byte");
  DEFSYM (Qchar, "char");
  DEFSYM (Qbool, "bool");
  DEFSYM (Qtype, "type");
  DEFSYM (Qsize_t, "size_t");
  DEFSYM (Qssize_t, "ssize_t");
  DEFSYM (Qpoint, "point");

  defsubr (&Shaiku_selection_data);
  defsubr (&Shaiku_selection_put);
  defsubr (&Shaiku_selection_owner_p);
  defsubr (&Shaiku_drag_message);

  haiku_dnd_frame = NULL;
}