ref: 22ab2c0b8237e1c51fdb479668ab764900f7d0c0
dir: /midend.c/
/*
* midend.c: general middle fragment sitting between the
* platform-specific front end and game-specific back end.
* Maintains a move list, takes care of Undo and Redo commands, and
* processes standard keystrokes for undo/redo/new/restart/quit.
*/
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "puzzles.h"
struct midend_data {
frontend *frontend;
random_state *random;
const game *ourgame;
char *seed;
int fresh_seed;
int nstates, statesize, statepos;
game_params **presets;
char **preset_names;
int npresets, presetsize;
game_params *params;
game_state **states;
game_drawstate *drawstate;
game_state *oldstate;
game_ui *ui;
float anim_time, anim_pos;
float flash_time, flash_pos;
int dir;
int pressed_mouse_button;
};
#define ensure(me) do { \
if ((me)->nstates >= (me)->statesize) { \
(me)->statesize = (me)->nstates + 128; \
(me)->states = sresize((me)->states, (me)->statesize, game_state *); \
} \
} while (0)
midend_data *midend_new(frontend *fe, const game *ourgame)
{
midend_data *me = snew(midend_data);
void *randseed;
int randseedsize;
get_random_seed(&randseed, &randseedsize);
me->frontend = fe;
me->ourgame = ourgame;
me->random = random_init(randseed, randseedsize);
me->nstates = me->statesize = me->statepos = 0;
me->states = NULL;
me->params = ourgame->default_params();
me->seed = NULL;
me->fresh_seed = FALSE;
me->drawstate = NULL;
me->oldstate = NULL;
me->presets = NULL;
me->preset_names = NULL;
me->npresets = me->presetsize = 0;
me->anim_time = me->anim_pos = 0.0F;
me->flash_time = me->flash_pos = 0.0F;
me->dir = 0;
me->ui = NULL;
me->pressed_mouse_button = 0;
sfree(randseed);
return me;
}
void midend_free(midend_data *me)
{
sfree(me->states);
sfree(me->seed);
me->ourgame->free_params(me->params);
sfree(me);
}
void midend_size(midend_data *me, int *x, int *y)
{
me->ourgame->size(me->params, x, y);
}
void midend_set_params(midend_data *me, game_params *params)
{
me->ourgame->free_params(me->params);
me->params = me->ourgame->dup_params(params);
}
void midend_new_game(midend_data *me)
{
while (me->nstates > 0)
me->ourgame->free_game(me->states[--me->nstates]);
if (me->drawstate)
me->ourgame->free_drawstate(me->drawstate);
assert(me->nstates == 0);
if (!me->fresh_seed) {
sfree(me->seed);
me->seed = me->ourgame->new_seed(me->params, me->random);
} else
me->fresh_seed = FALSE;
ensure(me);
me->states[me->nstates++] = me->ourgame->new_game(me->params, me->seed);
me->statepos = 1;
me->drawstate = me->ourgame->new_drawstate(me->states[0]);
if (me->ui)
me->ourgame->free_ui(me->ui);
me->ui = me->ourgame->new_ui(me->states[0]);
me->pressed_mouse_button = 0;
}
void midend_restart_game(midend_data *me)
{
while (me->nstates > 1)
me->ourgame->free_game(me->states[--me->nstates]);
me->statepos = me->nstates;
me->ourgame->free_ui(me->ui);
me->ui = me->ourgame->new_ui(me->states[0]);
}
static int midend_undo(midend_data *me)
{
if (me->statepos > 1) {
me->statepos--;
me->dir = -1;
return 1;
} else
return 0;
}
static int midend_redo(midend_data *me)
{
if (me->statepos < me->nstates) {
me->statepos++;
me->dir = +1;
return 1;
} else
return 0;
}
static void midend_finish_move(midend_data *me)
{
float flashtime;
if (me->oldstate || me->statepos > 1) {
flashtime = me->ourgame->flash_length(me->oldstate ? me->oldstate :
me->states[me->statepos-2],
me->states[me->statepos-1],
me->oldstate ? me->dir : +1);
if (flashtime > 0) {
me->flash_pos = 0.0F;
me->flash_time = flashtime;
}
}
if (me->oldstate)
me->ourgame->free_game(me->oldstate);
me->oldstate = NULL;
me->anim_pos = me->anim_time = 0;
me->dir = 0;
if (me->flash_time == 0 && me->anim_time == 0)
deactivate_timer(me->frontend);
else
activate_timer(me->frontend);
}
static void midend_stop_anim(midend_data *me)
{
if (me->oldstate || me->anim_time) {
midend_finish_move(me);
midend_redraw(me);
}
}
static int midend_really_process_key(midend_data *me, int x, int y, int button)
{
game_state *oldstate = me->ourgame->dup_game(me->states[me->statepos - 1]);
float anim_time;
if (button == 'n' || button == 'N' || button == '\x0E') {
midend_stop_anim(me);
midend_new_game(me);
midend_redraw(me);
return 1; /* never animate */
} else if (button == 'r' || button == 'R') {
midend_stop_anim(me);
midend_restart_game(me);
midend_redraw(me);
return 1; /* never animate */
} else if (button == 'u' || button == 'u' ||
button == '\x1A' || button == '\x1F') {
midend_stop_anim(me);
if (!midend_undo(me))
return 1;
} else if (button == '\x12') {
midend_stop_anim(me);
if (!midend_redo(me))
return 1;
} else if (button == 'q' || button == 'Q' || button == '\x11') {
me->ourgame->free_game(oldstate);
return 0;
} else {
game_state *s = me->ourgame->make_move(me->states[me->statepos-1],
me->ui, x, y, button);
if (s == me->states[me->statepos-1]) {
/*
* make_move() is allowed to return its input state to
* indicate that although no move has been made, the UI
* state has been updated and a redraw is called for.
*/
midend_redraw(me);
return 1;
} else if (s) {
midend_stop_anim(me);
while (me->nstates > me->statepos)
me->ourgame->free_game(me->states[--me->nstates]);
ensure(me);
me->states[me->nstates] = s;
me->statepos = ++me->nstates;
me->dir = +1;
} else {
me->ourgame->free_game(oldstate);
return 1;
}
}
/*
* See if this move requires an animation.
*/
anim_time = me->ourgame->anim_length(oldstate, me->states[me->statepos-1],
me->dir);
me->oldstate = oldstate;
if (anim_time > 0) {
me->anim_time = anim_time;
} else {
me->anim_time = 0.0;
midend_finish_move(me);
}
me->anim_pos = 0.0;
midend_redraw(me);
activate_timer(me->frontend);
return 1;
}
int midend_process_key(midend_data *me, int x, int y, int button)
{
int ret = 1;
/*
* Harmonise mouse drag and release messages.
*
* Some front ends might accidentally switch from sending, say,
* RIGHT_DRAG messages to sending LEFT_DRAG, half way through a
* drag. (This can happen on the Mac, for example, since
* RIGHT_DRAG is usually done using Command+drag, and if the
* user accidentally releases Command half way through the drag
* then there will be trouble.)
*
* It would be an O(number of front ends) annoyance to fix this
* in the front ends, but an O(number of back ends) annoyance
* to have each game capable of dealing with it. Therefore, we
* fix it _here_ in the common midend code so that it only has
* to be done once.
*
* The possible ways in which things can go screwy in the front
* end are:
*
* - in a system containing multiple physical buttons button
* presses can inadvertently overlap. We can see ABab (caps
* meaning button-down and lowercase meaning button-up) when
* the user had semantically intended AaBb.
*
* - in a system where one button is simulated by means of a
* modifier key and another button, buttons can mutate
* between press and release (possibly during drag). So we
* can see Ab instead of Aa.
*
* Definite requirements are:
*
* - button _presses_ must never be invented or destroyed. If
* the user presses two buttons in succession, the button
* presses must be transferred to the backend unchanged. So
* if we see AaBb , that's fine; if we see ABab (the button
* presses inadvertently overlapped) we must somehow
* `correct' it to AaBb.
*
* - every mouse action must end up looking like a press, zero
* or more drags, then a release. This allows back ends to
* make the _assumption_ that incoming mouse data will be
* sane in this regard, and not worry about the details.
*
* So my policy will be:
*
* - treat any button-up as a button-up for the currently
* pressed button, or ignore it if there is no currently
* pressed button.
*
* - treat any drag as a drag for the currently pressed
* button, or ignore it if there is no currently pressed
* button.
*
* - if we see a button-down while another button is currently
* pressed, invent a button-up for the first one and then
* pass the button-down through as before.
*
*/
if (IS_MOUSE_DRAG(button) || IS_MOUSE_RELEASE(button)) {
if (me->pressed_mouse_button) {
if (IS_MOUSE_DRAG(button)) {
button = me->pressed_mouse_button +
(LEFT_DRAG - LEFT_BUTTON);
} else {
button = me->pressed_mouse_button +
(LEFT_RELEASE - LEFT_BUTTON);
}
} else
return ret; /* ignore it */
} else if (IS_MOUSE_DOWN(button) && me->pressed_mouse_button) {
/*
* Fabricate a button-up for the previously pressed button.
*/
ret = ret && midend_really_process_key
(me, x, y, (me->pressed_mouse_button +
(LEFT_RELEASE - LEFT_BUTTON)));
}
/*
* Now send on the event we originally received.
*/
ret = ret && midend_really_process_key(me, x, y, button);
/*
* And update the currently pressed button.
*/
if (IS_MOUSE_RELEASE(button))
me->pressed_mouse_button = 0;
else if (IS_MOUSE_DOWN(button))
me->pressed_mouse_button = button;
return ret;
}
void midend_redraw(midend_data *me)
{
if (me->statepos > 0 && me->drawstate) {
start_draw(me->frontend);
if (me->oldstate && me->anim_time > 0 &&
me->anim_pos < me->anim_time) {
assert(me->dir != 0);
me->ourgame->redraw(me->frontend, me->drawstate, me->oldstate,
me->states[me->statepos-1], me->dir,
me->ui, me->anim_pos, me->flash_pos);
} else {
me->ourgame->redraw(me->frontend, me->drawstate, NULL,
me->states[me->statepos-1], +1 /*shrug*/,
me->ui, 0.0, me->flash_pos);
}
end_draw(me->frontend);
}
}
void midend_timer(midend_data *me, float tplus)
{
me->anim_pos += tplus;
if (me->anim_pos >= me->anim_time ||
me->anim_time == 0 || !me->oldstate) {
if (me->anim_time > 0)
midend_finish_move(me);
}
me->flash_pos += tplus;
if (me->flash_pos >= me->flash_time || me->flash_time == 0) {
me->flash_pos = me->flash_time = 0;
}
if (me->flash_time == 0 && me->anim_time == 0)
deactivate_timer(me->frontend);
midend_redraw(me);
}
float *midend_colours(midend_data *me, int *ncolours)
{
game_state *state = NULL;
float *ret;
if (me->nstates == 0) {
char *seed = me->ourgame->new_seed(me->params, me->random);
state = me->ourgame->new_game(me->params, seed);
sfree(seed);
} else
state = me->states[0];
ret = me->ourgame->colours(me->frontend, state, ncolours);
if (me->nstates == 0)
me->ourgame->free_game(state);
return ret;
}
int midend_num_presets(midend_data *me)
{
if (!me->npresets) {
char *name;
game_params *preset;
while (me->ourgame->fetch_preset(me->npresets, &name, &preset)) {
if (me->presetsize <= me->npresets) {
me->presetsize = me->npresets + 10;
me->presets = sresize(me->presets, me->presetsize,
game_params *);
me->preset_names = sresize(me->preset_names, me->presetsize,
char *);
}
me->presets[me->npresets] = preset;
me->preset_names[me->npresets] = name;
me->npresets++;
}
}
return me->npresets;
}
void midend_fetch_preset(midend_data *me, int n,
char **name, game_params **params)
{
assert(n >= 0 && n < me->npresets);
*name = me->preset_names[n];
*params = me->presets[n];
}
int midend_wants_statusbar(midend_data *me)
{
return me->ourgame->wants_statusbar();
}
config_item *midend_get_config(midend_data *me, int which, char **wintitle)
{
char *titlebuf, *parstr;
config_item *ret;
titlebuf = snewn(40 + strlen(me->ourgame->name), char);
switch (which) {
case CFG_SETTINGS:
sprintf(titlebuf, "%s configuration", me->ourgame->name);
*wintitle = dupstr(titlebuf);
return me->ourgame->configure(me->params);
case CFG_SEED:
sprintf(titlebuf, "%s game selection", me->ourgame->name);
*wintitle = dupstr(titlebuf);
ret = snewn(2, config_item);
ret[0].type = C_STRING;
ret[0].name = "Game ID";
ret[0].ival = 0;
/*
* The text going in here will be a string encoding of the
* parameters, plus a colon, plus the game seed. This is a
* full game ID.
*/
parstr = me->ourgame->encode_params(me->params);
ret[0].sval = snewn(strlen(parstr) + strlen(me->seed) + 2, char);
sprintf(ret[0].sval, "%s:%s", parstr, me->seed);
sfree(parstr);
ret[1].type = C_END;
ret[1].name = ret[1].sval = NULL;
ret[1].ival = 0;
return ret;
}
assert(!"We shouldn't be here");
return NULL;
}
char *midend_game_id(midend_data *me, char *id, int def_seed)
{
char *error, *par, *seed;
game_params *params;
seed = strchr(id, ':');
if (seed) {
/*
* We have a colon separating parameters from game seed. So
* `par' now points to the parameters string, and `seed' to
* the seed string.
*/
*seed++ = '\0';
par = id;
} else {
/*
* We only have one string. Depending on `def_seed', we
* take it to be either parameters or seed.
*/
if (def_seed) {
seed = id;
par = NULL;
} else {
seed = NULL;
par = id;
}
}
if (par) {
params = me->ourgame->decode_params(par);
error = me->ourgame->validate_params(params);
if (error) {
me->ourgame->free_params(params);
return error;
}
me->ourgame->free_params(me->params);
me->params = params;
}
if (seed) {
error = me->ourgame->validate_seed(me->params, seed);
if (error)
return error;
sfree(me->seed);
me->seed = dupstr(seed);
me->fresh_seed = TRUE;
}
return NULL;
}
char *midend_set_config(midend_data *me, int which, config_item *cfg)
{
char *error;
game_params *params;
switch (which) {
case CFG_SETTINGS:
params = me->ourgame->custom_params(cfg);
error = me->ourgame->validate_params(params);
if (error) {
me->ourgame->free_params(params);
return error;
}
me->ourgame->free_params(me->params);
me->params = params;
break;
case CFG_SEED:
error = midend_game_id(me, cfg[0].sval, TRUE);
if (error)
return error;
break;
}
return NULL;
}