2 * midend.c: general middle fragment sitting between the
3 * platform-specific front end and game-specific back end.
4 * Maintains a move list, takes care of Undo and Redo commands, and
5 * processes standard keystrokes for undo/redo/new/restart/quit.
14 enum { DEF_PARAMS
, DEF_SEED
, DEF_DESC
}; /* for midend_game_id_int */
16 struct midend_state_entry
{
18 int special
; /* created by solve or restart */
27 game_aux_info
*aux_info
;
28 enum { GOT_SEED
, GOT_DESC
, GOT_NOTHING
} genmode
;
29 int nstates
, statesize
, statepos
;
31 game_params
**presets
;
33 int npresets
, presetsize
;
35 game_params
*params
, *tmpparams
;
36 struct midend_state_entry
*states
;
37 game_drawstate
*drawstate
;
40 float anim_time
, anim_pos
;
41 float flash_time
, flash_pos
;
44 int pressed_mouse_button
;
47 #define ensure(me) do { \
48 if ((me)->nstates >= (me)->statesize) { \
49 (me)->statesize = (me)->nstates + 128; \
50 (me)->states = sresize((me)->states, (me)->statesize, \
51 struct midend_state_entry); \
55 midend_data
*midend_new(frontend
*fe
, const game
*ourgame
)
57 midend_data
*me
= snew(midend_data
);
61 get_random_seed(&randseed
, &randseedsize
);
64 me
->ourgame
= ourgame
;
65 me
->random
= random_init(randseed
, randseedsize
);
66 me
->nstates
= me
->statesize
= me
->statepos
= 0;
68 me
->params
= ourgame
->default_params();
73 me
->genmode
= GOT_NOTHING
;
77 me
->preset_names
= NULL
;
78 me
->npresets
= me
->presetsize
= 0;
79 me
->anim_time
= me
->anim_pos
= 0.0F
;
80 me
->flash_time
= me
->flash_pos
= 0.0F
;
83 me
->pressed_mouse_button
= 0;
90 void midend_free(midend_data
*me
)
95 random_free(me
->random
);
97 me
->ourgame
->free_aux_info(me
->aux_info
);
98 me
->ourgame
->free_params(me
->params
);
100 me
->ourgame
->free_params(me
->tmpparams
);
104 void midend_size(midend_data
*me
, int *x
, int *y
)
106 me
->ourgame
->size(me
->params
, x
, y
);
109 void midend_set_params(midend_data
*me
, game_params
*params
)
111 me
->ourgame
->free_params(me
->params
);
112 me
->params
= me
->ourgame
->dup_params(params
);
115 void midend_new_game(midend_data
*me
)
117 while (me
->nstates
> 0)
118 me
->ourgame
->free_game(me
->states
[--me
->nstates
].state
);
121 me
->ourgame
->free_drawstate(me
->drawstate
);
123 assert(me
->nstates
== 0);
125 if (me
->genmode
== GOT_DESC
) {
126 me
->genmode
= GOT_NOTHING
;
130 if (me
->genmode
== GOT_SEED
) {
131 me
->genmode
= GOT_NOTHING
;
134 * Generate a new random seed. 15 digits comes to about
135 * 48 bits, which should be more than enough.
140 for (i
= 0; i
< 15; i
++)
141 newseed
[i
] = '0' + random_upto(me
->random
, 10);
143 me
->seedstr
= dupstr(newseed
);
148 me
->ourgame
->free_aux_info(me
->aux_info
);
151 rs
= random_init(me
->seedstr
, strlen(me
->seedstr
));
152 me
->desc
= me
->ourgame
->new_desc
153 (me
->tmpparams ? me
->tmpparams
: me
->params
, rs
, &me
->aux_info
);
157 me
->ourgame
->free_params(me
->tmpparams
);
158 me
->tmpparams
= NULL
;
163 me
->states
[me
->nstates
].state
= me
->ourgame
->new_game(me
->params
, me
->desc
);
164 me
->states
[me
->nstates
].special
= TRUE
;
167 me
->drawstate
= me
->ourgame
->new_drawstate(me
->states
[0].state
);
169 me
->ourgame
->free_ui(me
->ui
);
170 me
->ui
= me
->ourgame
->new_ui(me
->states
[0].state
);
171 me
->pressed_mouse_button
= 0;
174 static int midend_undo(midend_data
*me
)
176 if (me
->statepos
> 1) {
184 static int midend_redo(midend_data
*me
)
186 if (me
->statepos
< me
->nstates
) {
194 static void midend_finish_move(midend_data
*me
)
199 * We do not flash if the later of the two states is special.
200 * This covers both forward Solve moves and backward (undone)
203 if ((me
->oldstate
|| me
->statepos
> 1) &&
204 ((me
->dir
> 0 && !me
->states
[me
->statepos
-1].special
) ||
205 (me
->dir
< 0 && me
->statepos
< me
->nstates
&&
206 !me
->states
[me
->statepos
].special
))) {
207 flashtime
= me
->ourgame
->flash_length(me
->oldstate ? me
->oldstate
:
208 me
->states
[me
->statepos
-2].state
,
209 me
->states
[me
->statepos
-1].state
,
210 me
->oldstate ? me
->dir
: +1);
212 me
->flash_pos
= 0.0F
;
213 me
->flash_time
= flashtime
;
218 me
->ourgame
->free_game(me
->oldstate
);
220 me
->anim_pos
= me
->anim_time
= 0;
223 if (me
->flash_time
== 0 && me
->anim_time
== 0)
224 deactivate_timer(me
->frontend
);
226 activate_timer(me
->frontend
);
229 static void midend_stop_anim(midend_data
*me
)
231 if (me
->oldstate
|| me
->anim_time
) {
232 midend_finish_move(me
);
237 void midend_restart_game(midend_data
*me
)
241 assert(me
->statepos
>= 1);
242 if (me
->statepos
== 1)
243 return; /* no point doing anything at all! */
245 s
= me
->ourgame
->dup_game(me
->states
[0].state
);
248 * Now enter the restarted state as the next move.
250 midend_stop_anim(me
);
251 while (me
->nstates
> me
->statepos
)
252 me
->ourgame
->free_game(me
->states
[--me
->nstates
].state
);
254 me
->states
[me
->nstates
].state
= s
;
255 me
->states
[me
->nstates
].special
= TRUE
; /* we just restarted */
256 me
->statepos
= ++me
->nstates
;
258 midend_finish_move(me
);
260 activate_timer(me
->frontend
);
263 static int midend_really_process_key(midend_data
*me
, int x
, int y
, int button
)
265 game_state
*oldstate
=
266 me
->ourgame
->dup_game(me
->states
[me
->statepos
- 1].state
);
267 int special
= FALSE
, gotspecial
= FALSE
;
270 if (button
== 'n' || button
== 'N' || button
== '\x0E') {
271 midend_stop_anim(me
);
274 return 1; /* never animate */
275 } else if (button
== 'r' || button
== 'R') {
276 midend_stop_anim(me
);
277 midend_restart_game(me
);
279 return 1; /* never animate */
280 } else if (button
== 'u' || button
== 'u' ||
281 button
== '\x1A' || button
== '\x1F') {
282 midend_stop_anim(me
);
283 special
= me
->states
[me
->statepos
-1].special
;
285 if (!midend_undo(me
))
287 } else if (button
== '\x12') {
288 midend_stop_anim(me
);
289 if (!midend_redo(me
))
291 } else if (button
== 'q' || button
== 'Q' || button
== '\x11') {
292 me
->ourgame
->free_game(oldstate
);
296 me
->ourgame
->make_move(me
->states
[me
->statepos
-1].state
,
297 me
->ui
, x
, y
, button
);
299 if (s
== me
->states
[me
->statepos
-1].state
) {
301 * make_move() is allowed to return its input state to
302 * indicate that although no move has been made, the UI
303 * state has been updated and a redraw is called for.
308 midend_stop_anim(me
);
309 while (me
->nstates
> me
->statepos
)
310 me
->ourgame
->free_game(me
->states
[--me
->nstates
].state
);
312 me
->states
[me
->nstates
].state
= s
;
313 me
->states
[me
->nstates
].special
= FALSE
; /* normal move */
314 me
->statepos
= ++me
->nstates
;
317 me
->ourgame
->free_game(oldstate
);
323 special
= me
->states
[me
->statepos
-1].special
;
326 * See if this move requires an animation.
331 anim_time
= me
->ourgame
->anim_length(oldstate
,
332 me
->states
[me
->statepos
-1].state
,
336 me
->oldstate
= oldstate
;
338 me
->anim_time
= anim_time
;
341 midend_finish_move(me
);
347 activate_timer(me
->frontend
);
352 int midend_process_key(midend_data
*me
, int x
, int y
, int button
)
357 * Harmonise mouse drag and release messages.
359 * Some front ends might accidentally switch from sending, say,
360 * RIGHT_DRAG messages to sending LEFT_DRAG, half way through a
361 * drag. (This can happen on the Mac, for example, since
362 * RIGHT_DRAG is usually done using Command+drag, and if the
363 * user accidentally releases Command half way through the drag
364 * then there will be trouble.)
366 * It would be an O(number of front ends) annoyance to fix this
367 * in the front ends, but an O(number of back ends) annoyance
368 * to have each game capable of dealing with it. Therefore, we
369 * fix it _here_ in the common midend code so that it only has
372 * The possible ways in which things can go screwy in the front
375 * - in a system containing multiple physical buttons button
376 * presses can inadvertently overlap. We can see ABab (caps
377 * meaning button-down and lowercase meaning button-up) when
378 * the user had semantically intended AaBb.
380 * - in a system where one button is simulated by means of a
381 * modifier key and another button, buttons can mutate
382 * between press and release (possibly during drag). So we
383 * can see Ab instead of Aa.
385 * Definite requirements are:
387 * - button _presses_ must never be invented or destroyed. If
388 * the user presses two buttons in succession, the button
389 * presses must be transferred to the backend unchanged. So
390 * if we see AaBb , that's fine; if we see ABab (the button
391 * presses inadvertently overlapped) we must somehow
392 * `correct' it to AaBb.
394 * - every mouse action must end up looking like a press, zero
395 * or more drags, then a release. This allows back ends to
396 * make the _assumption_ that incoming mouse data will be
397 * sane in this regard, and not worry about the details.
399 * So my policy will be:
401 * - treat any button-up as a button-up for the currently
402 * pressed button, or ignore it if there is no currently
405 * - treat any drag as a drag for the currently pressed
406 * button, or ignore it if there is no currently pressed
409 * - if we see a button-down while another button is currently
410 * pressed, invent a button-up for the first one and then
411 * pass the button-down through as before.
414 if (IS_MOUSE_DRAG(button
) || IS_MOUSE_RELEASE(button
)) {
415 if (me
->pressed_mouse_button
) {
416 if (IS_MOUSE_DRAG(button
)) {
417 button
= me
->pressed_mouse_button
+
418 (LEFT_DRAG
- LEFT_BUTTON
);
420 button
= me
->pressed_mouse_button
+
421 (LEFT_RELEASE
- LEFT_BUTTON
);
424 return ret
; /* ignore it */
425 } else if (IS_MOUSE_DOWN(button
) && me
->pressed_mouse_button
) {
427 * Fabricate a button-up for the previously pressed button.
429 ret
= ret
&& midend_really_process_key
430 (me
, x
, y
, (me
->pressed_mouse_button
+
431 (LEFT_RELEASE
- LEFT_BUTTON
)));
435 * Now send on the event we originally received.
437 ret
= ret
&& midend_really_process_key(me
, x
, y
, button
);
440 * And update the currently pressed button.
442 if (IS_MOUSE_RELEASE(button
))
443 me
->pressed_mouse_button
= 0;
444 else if (IS_MOUSE_DOWN(button
))
445 me
->pressed_mouse_button
= button
;
450 void midend_redraw(midend_data
*me
)
452 if (me
->statepos
> 0 && me
->drawstate
) {
453 start_draw(me
->frontend
);
454 if (me
->oldstate
&& me
->anim_time
> 0 &&
455 me
->anim_pos
< me
->anim_time
) {
456 assert(me
->dir
!= 0);
457 me
->ourgame
->redraw(me
->frontend
, me
->drawstate
, me
->oldstate
,
458 me
->states
[me
->statepos
-1].state
, me
->dir
,
459 me
->ui
, me
->anim_pos
, me
->flash_pos
);
461 me
->ourgame
->redraw(me
->frontend
, me
->drawstate
, NULL
,
462 me
->states
[me
->statepos
-1].state
, +1 /*shrug*/,
463 me
->ui
, 0.0, me
->flash_pos
);
465 end_draw(me
->frontend
);
469 void midend_timer(midend_data
*me
, float tplus
)
471 me
->anim_pos
+= tplus
;
472 if (me
->anim_pos
>= me
->anim_time
||
473 me
->anim_time
== 0 || !me
->oldstate
) {
474 if (me
->anim_time
> 0)
475 midend_finish_move(me
);
477 me
->flash_pos
+= tplus
;
478 if (me
->flash_pos
>= me
->flash_time
|| me
->flash_time
== 0) {
479 me
->flash_pos
= me
->flash_time
= 0;
481 if (me
->flash_time
== 0 && me
->anim_time
== 0)
482 deactivate_timer(me
->frontend
);
486 float *midend_colours(midend_data
*me
, int *ncolours
)
488 game_state
*state
= NULL
;
491 if (me
->nstates
== 0) {
492 game_aux_info
*aux
= NULL
;
493 char *desc
= me
->ourgame
->new_desc(me
->params
, me
->random
, &aux
);
494 state
= me
->ourgame
->new_game(me
->params
, desc
);
497 me
->ourgame
->free_aux_info(aux
);
499 state
= me
->states
[0].state
;
501 ret
= me
->ourgame
->colours(me
->frontend
, state
, ncolours
);
503 if (me
->nstates
== 0)
504 me
->ourgame
->free_game(state
);
509 int midend_num_presets(midend_data
*me
)
515 while (me
->ourgame
->fetch_preset(me
->npresets
, &name
, &preset
)) {
516 if (me
->presetsize
<= me
->npresets
) {
517 me
->presetsize
= me
->npresets
+ 10;
518 me
->presets
= sresize(me
->presets
, me
->presetsize
,
520 me
->preset_names
= sresize(me
->preset_names
, me
->presetsize
,
524 me
->presets
[me
->npresets
] = preset
;
525 me
->preset_names
[me
->npresets
] = name
;
533 void midend_fetch_preset(midend_data
*me
, int n
,
534 char **name
, game_params
**params
)
536 assert(n
>= 0 && n
< me
->npresets
);
537 *name
= me
->preset_names
[n
];
538 *params
= me
->presets
[n
];
541 int midend_wants_statusbar(midend_data
*me
)
543 return me
->ourgame
->wants_statusbar();
546 config_item
*midend_get_config(midend_data
*me
, int which
, char **wintitle
)
548 char *titlebuf
, *parstr
;
551 titlebuf
= snewn(40 + strlen(me
->ourgame
->name
), char);
555 sprintf(titlebuf
, "%s configuration", me
->ourgame
->name
);
556 *wintitle
= dupstr(titlebuf
);
557 return me
->ourgame
->configure(me
->params
);
560 sprintf(titlebuf
, "%s %s selection", me
->ourgame
->name
,
561 which
== CFG_SEED ?
"random" : "game");
562 *wintitle
= dupstr(titlebuf
);
564 ret
= snewn(2, config_item
);
566 ret
[0].type
= C_STRING
;
567 if (which
== CFG_SEED
)
568 ret
[0].name
= "Game random seed";
570 ret
[0].name
= "Game ID";
573 * For CFG_DESC the text going in here will be a string
574 * encoding of the restricted parameters, plus a colon,
575 * plus the game description. For CFG_SEED it will be the
576 * full parameters, plus a hash, plus the random seed data.
577 * Either of these is a valid full game ID (although only
578 * the former is likely to persist across many code
581 parstr
= me
->ourgame
->encode_params(me
->params
, which
== CFG_SEED
);
582 if (which
== CFG_DESC
) {
583 ret
[0].sval
= snewn(strlen(parstr
) + strlen(me
->desc
) + 2, char);
584 sprintf(ret
[0].sval
, "%s:%s", parstr
, me
->desc
);
585 } else if (me
->seedstr
) {
586 ret
[0].sval
= snewn(strlen(parstr
) + strlen(me
->seedstr
) + 2, char);
587 sprintf(ret
[0].sval
, "%s#%s", parstr
, me
->seedstr
);
590 * If the current game was not randomly generated, the
591 * best we can do is to give a template for typing a
594 ret
[0].sval
= snewn(strlen(parstr
) + 2, char);
595 sprintf(ret
[0].sval
, "%s#", parstr
);
600 ret
[1].name
= ret
[1].sval
= NULL
;
606 assert(!"We shouldn't be here");
610 static char *midend_game_id_int(midend_data
*me
, char *id
, int defmode
)
612 char *error
, *par
, *desc
, *seed
;
614 seed
= strchr(id
, '#');
615 desc
= strchr(id
, ':');
617 if (desc
&& (!seed
|| desc
< seed
)) {
619 * We have a colon separating parameters from game
620 * description. So `par' now points to the parameters
621 * string, and `desc' to the description string.
626 } else if (seed
&& (!desc
|| seed
< desc
)) {
628 * We have a hash separating parameters from random seed.
629 * So `par' now points to the parameters string, and `seed'
630 * to the seed string.
637 * We only have one string. Depending on `defmode', we take
638 * it to be either parameters, seed or description.
640 if (defmode
== DEF_SEED
) {
643 } else if (defmode
== DEF_DESC
) {
653 game_params
*tmpparams
;
654 tmpparams
= me
->ourgame
->dup_params(me
->params
);
655 me
->ourgame
->decode_params(tmpparams
, par
);
656 error
= me
->ourgame
->validate_params(tmpparams
);
658 me
->ourgame
->free_params(tmpparams
);
662 me
->ourgame
->free_params(me
->tmpparams
);
663 me
->tmpparams
= tmpparams
;
666 * Now filter only the persistent parts of this state into
667 * the long-term params structure, unless we've _only_
668 * received a params string in which case the whole lot is
672 char *tmpstr
= me
->ourgame
->encode_params(tmpparams
, FALSE
);
673 me
->ourgame
->decode_params(me
->params
, tmpstr
);
675 me
->ourgame
->free_params(me
->params
);
676 me
->params
= me
->ourgame
->dup_params(tmpparams
);
681 error
= me
->ourgame
->validate_desc(me
->params
, desc
);
686 me
->desc
= dupstr(desc
);
687 me
->genmode
= GOT_DESC
;
689 me
->ourgame
->free_aux_info(me
->aux_info
);
695 me
->seedstr
= dupstr(seed
);
696 me
->genmode
= GOT_SEED
;
702 char *midend_game_id(midend_data
*me
, char *id
)
704 return midend_game_id_int(me
, id
, DEF_PARAMS
);
707 char *midend_set_config(midend_data
*me
, int which
, config_item
*cfg
)
714 params
= me
->ourgame
->custom_params(cfg
);
715 error
= me
->ourgame
->validate_params(params
);
718 me
->ourgame
->free_params(params
);
722 me
->ourgame
->free_params(me
->params
);
728 error
= midend_game_id_int(me
, cfg
[0].sval
,
729 (which
== CFG_SEED ? DEF_SEED
: DEF_DESC
));
738 char *midend_text_format(midend_data
*me
)
740 if (me
->ourgame
->can_format_as_text
&& me
->statepos
> 0)
741 return me
->ourgame
->text_format(me
->states
[me
->statepos
-1].state
);
746 char *midend_solve(midend_data
*me
)
751 if (!me
->ourgame
->can_solve
)
752 return "This game does not support the Solve operation";
754 if (me
->statepos
< 1)
755 return "No game set up to solve"; /* _shouldn't_ happen! */
757 msg
= "Solve operation failed"; /* game _should_ overwrite on error */
758 s
= me
->ourgame
->solve(me
->states
[0].state
, me
->aux_info
, &msg
);
763 * Now enter the solved state as the next move.
765 midend_stop_anim(me
);
766 while (me
->nstates
> me
->statepos
)
767 me
->ourgame
->free_game(me
->states
[--me
->nstates
].state
);
769 me
->states
[me
->nstates
].state
= s
;
770 me
->states
[me
->nstates
].special
= TRUE
; /* created using solve */
771 me
->statepos
= ++me
->nstates
;
773 midend_finish_move(me
);
775 activate_timer(me
->frontend
);