X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/puzzles/blobdiff_plain/6f2d8d7c70f6bbf8bce982ced1fa879e967afbbf..f467efadd6d03a2b7d3a7dfcd9ffa4a6eb144c5a:/midend.c

diff --git a/midend.c b/midend.c
index dbbaad4..dec0cc9 100644
--- a/midend.c
+++ b/midend.c
@@ -2,31 +2,40 @@
  * 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.
+ * processes standard keystrokes for undo/redo/new/quit.
  */
 
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>
+#include <stdlib.h>
+#include <ctype.h>
 
 #include "puzzles.h"
 
+enum { DEF_PARAMS, DEF_SEED, DEF_DESC };   /* for midend_game_id_int */
+
+struct midend_state_entry {
+    game_state *state;
+    int special;                       /* created by solve or restart */
+};
+
 struct midend_data {
     frontend *frontend;
     random_state *random;
     const game *ourgame;
 
-    char *seed;
+    char *desc, *seedstr;
     game_aux_info *aux_info;
-    int fresh_seed;
+    enum { GOT_SEED, GOT_DESC, GOT_NOTHING } genmode;
     int nstates, statesize, statepos;
 
     game_params **presets;
     char **preset_names;
     int npresets, presetsize;
 
-    game_params *params;
-    game_state **states;
+    game_params *params, *curparams;
+    struct midend_state_entry *states;
     game_drawstate *drawstate;
     game_state *oldstate;
     game_ui *ui;
@@ -34,13 +43,20 @@ struct midend_data {
     float flash_time, flash_pos;
     int dir;
 
+    int timing;
+    float elapsed;
+    char *laststatus;
+
     int pressed_mouse_button;
+
+    int winwidth, winheight;
 };
 
 #define ensure(me) do { \
     if ((me)->nstates >= (me)->statesize) { \
 	(me)->statesize = (me)->nstates + 128; \
-	(me)->states = sresize((me)->states, (me)->statesize, game_state *); \
+	(me)->states = sresize((me)->states, (me)->statesize, \
+                               struct midend_state_entry); \
     } \
 } while (0)
 
@@ -58,9 +74,11 @@ midend_data *midend_new(frontend *fe, const game *ourgame)
     me->nstates = me->statesize = me->statepos = 0;
     me->states = NULL;
     me->params = ourgame->default_params();
-    me->seed = NULL;
+    me->curparams = NULL;
+    me->desc = NULL;
+    me->seedstr = NULL;
     me->aux_info = NULL;
-    me->fresh_seed = FALSE;
+    me->genmode = GOT_NOTHING;
     me->drawstate = NULL;
     me->oldstate = NULL;
     me->presets = NULL;
@@ -71,25 +89,59 @@ midend_data *midend_new(frontend *fe, const game *ourgame)
     me->dir = 0;
     me->ui = NULL;
     me->pressed_mouse_button = 0;
+    me->laststatus = NULL;
+    me->timing = FALSE;
+    me->elapsed = 0.0F;
+    me->winwidth = me->winheight = 0;
 
     sfree(randseed);
 
     return me;
 }
 
+static void midend_free_game(midend_data *me)
+{
+    while (me->nstates > 0)
+	me->ourgame->free_game(me->states[--me->nstates].state);
+
+    if (me->drawstate)
+        me->ourgame->free_drawstate(me->drawstate);
+}
+
 void midend_free(midend_data *me)
 {
+    int i;
+
+    midend_free_game(me);
+
+    random_free(me->random);
     sfree(me->states);
-    sfree(me->seed);
+    sfree(me->desc);
+    sfree(me->seedstr);
     if (me->aux_info)
 	me->ourgame->free_aux_info(me->aux_info);
     me->ourgame->free_params(me->params);
+    if (me->npresets) {
+	for (i = 0; i < me->npresets; i++) {
+	    sfree(me->presets[i]);
+	    sfree(me->preset_names[i]);
+	}
+	sfree(me->presets);
+	sfree(me->preset_names);
+    }
+    if (me->ui)
+        me->ourgame->free_ui(me->ui);
+    if (me->curparams)
+        me->ourgame->free_params(me->curparams);
+    sfree(me->laststatus);
     sfree(me);
 }
 
-void midend_size(midend_data *me, int *x, int *y)
+void midend_size(midend_data *me, int *x, int *y, int expand)
 {
-    me->ourgame->size(me->params, x, y);
+    me->ourgame->size(me->params, me->drawstate, x, y, expand);
+    me->winwidth = *x;
+    me->winheight = *y;
 }
 
 void midend_set_params(midend_data *me, game_params *params)
@@ -98,48 +150,101 @@ void midend_set_params(midend_data *me, game_params *params)
     me->params = me->ourgame->dup_params(params);
 }
 
-void midend_new_game(midend_data *me)
+static void midend_set_timer(midend_data *me)
 {
-    while (me->nstates > 0)
-	me->ourgame->free_game(me->states[--me->nstates]);
+    me->timing = (me->ourgame->is_timed &&
+		  me->ourgame->timing_state(me->states[me->statepos-1].state));
+    if (me->timing || me->flash_time || me->anim_time)
+	activate_timer(me->frontend);
+    else
+	deactivate_timer(me->frontend);
+}
+
+static void midend_size_new_drawstate(midend_data *me)
+{
+    me->ourgame->size(me->params, me->drawstate, &me->winwidth, &me->winheight,
+                      TRUE);
+}
 
+void midend_force_redraw(midend_data *me)
+{
     if (me->drawstate)
         me->ourgame->free_drawstate(me->drawstate);
+    me->drawstate = me->ourgame->new_drawstate(me->states[0].state);
+    midend_size_new_drawstate(me);
+    midend_redraw(me);
+}
+
+void midend_new_game(midend_data *me)
+{
+    midend_free_game(me);
 
     assert(me->nstates == 0);
 
-    if (!me->fresh_seed) {
-	sfree(me->seed);
+    if (me->genmode == GOT_DESC) {
+	me->genmode = GOT_NOTHING;
+    } else {
+        random_state *rs;
+
+        if (me->genmode == GOT_SEED) {
+            me->genmode = GOT_NOTHING;
+        } else {
+            /*
+             * Generate a new random seed. 15 digits comes to about
+             * 48 bits, which should be more than enough.
+             * 
+             * I'll avoid putting a leading zero on the number,
+             * just in case it confuses anybody who thinks it's
+             * processed as an integer rather than a string.
+             */
+            char newseed[16];
+            int i;
+            newseed[15] = '\0';
+            newseed[0] = '1' + random_upto(me->random, 9);
+            for (i = 1; i < 15; i++)
+                newseed[i] = '0' + random_upto(me->random, 10);
+            sfree(me->seedstr);
+            me->seedstr = dupstr(newseed);
+
+	    if (me->curparams)
+		me->ourgame->free_params(me->curparams);
+	    me->curparams = me->ourgame->dup_params(me->params);
+        }
+
+	sfree(me->desc);
 	if (me->aux_info)
 	    me->ourgame->free_aux_info(me->aux_info);
 	me->aux_info = NULL;
-	me->seed = me->ourgame->new_seed(me->params, me->random,
-					 &me->aux_info);
-    } else
-	me->fresh_seed = FALSE;
+
+        rs = random_init(me->seedstr, strlen(me->seedstr));
+        me->desc = me->ourgame->new_desc(me->curparams, rs,
+					 &me->aux_info, TRUE);
+        random_free(rs);
+    }
 
     ensure(me);
-    me->states[me->nstates++] = me->ourgame->new_game(me->params, me->seed);
+    me->states[me->nstates].state =
+	me->ourgame->new_game(me, me->params, me->desc);
+    me->states[me->nstates].special = TRUE;
+    me->nstates++;
     me->statepos = 1;
-    me->drawstate = me->ourgame->new_drawstate(me->states[0]);
+    me->drawstate = me->ourgame->new_drawstate(me->states[0].state);
+    midend_size_new_drawstate(me);
+    me->elapsed = 0.0F;
+    midend_set_timer(me);
     if (me->ui)
         me->ourgame->free_ui(me->ui);
-    me->ui = me->ourgame->new_ui(me->states[0]);
+    me->ui = me->ourgame->new_ui(me->states[0].state);
     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) {
+        if (me->ui)
+            me->ourgame->changed_state(me->ui,
+                                       me->states[me->statepos-1].state,
+                                       me->states[me->statepos-2].state);
 	me->statepos--;
         me->dir = -1;
         return 1;
@@ -150,6 +255,10 @@ static int midend_undo(midend_data *me)
 static int midend_redo(midend_data *me)
 {
     if (me->statepos < me->nstates) {
+        if (me->ui)
+            me->ourgame->changed_state(me->ui,
+                                       me->states[me->statepos-1].state,
+                                       me->states[me->statepos].state);
 	me->statepos++;
         me->dir = +1;
         return 1;
@@ -161,11 +270,20 @@ static void midend_finish_move(midend_data *me)
 {
     float flashtime;
 
-    if (me->oldstate || me->statepos > 1) {
+    /*
+     * We do not flash if the later of the two states is special.
+     * This covers both forward Solve moves and backward (undone)
+     * Restart moves.
+     */
+    if ((me->oldstate || me->statepos > 1) &&
+        ((me->dir > 0 && !me->states[me->statepos-1].special) ||
+         (me->dir < 0 && me->statepos < me->nstates &&
+          !me->states[me->statepos].special))) {
 	flashtime = me->ourgame->flash_length(me->oldstate ? me->oldstate :
-					      me->states[me->statepos-2],
-					      me->states[me->statepos-1],
-					      me->oldstate ? me->dir : +1);
+					      me->states[me->statepos-2].state,
+					      me->states[me->statepos-1].state,
+					      me->oldstate ? me->dir : +1,
+					      me->ui);
 	if (flashtime > 0) {
 	    me->flash_pos = 0.0F;
 	    me->flash_time = flashtime;
@@ -178,13 +296,10 @@ static void midend_finish_move(midend_data *me)
     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);
+    midend_set_timer(me);
 }
 
-static void midend_stop_anim(midend_data *me)
+void midend_stop_anim(midend_data *me)
 {
     if (me->oldstate || me->anim_time) {
 	midend_finish_move(me);
@@ -192,66 +307,107 @@ static void midend_stop_anim(midend_data *me)
     }
 }
 
+void midend_restart_game(midend_data *me)
+{
+    game_state *s;
+
+    midend_stop_anim(me);
+
+    assert(me->statepos >= 1);
+    if (me->statepos == 1)
+        return;                        /* no point doing anything at all! */
+
+    s = me->ourgame->dup_game(me->states[0].state);
+
+    /*
+     * Now enter the restarted state as the next move.
+     */
+    midend_stop_anim(me);
+    while (me->nstates > me->statepos)
+	me->ourgame->free_game(me->states[--me->nstates].state);
+    ensure(me);
+    me->states[me->nstates].state = s;
+    me->states[me->nstates].special = TRUE;   /* we just restarted */
+    me->statepos = ++me->nstates;
+    if (me->ui)
+        me->ourgame->changed_state(me->ui,
+                                   me->states[me->statepos-2].state,
+                                   me->states[me->statepos-1].state);
+    me->anim_time = 0.0;
+    midend_finish_move(me);
+    midend_redraw(me);
+    midend_set_timer(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]);
+    game_state *oldstate =
+        me->ourgame->dup_game(me->states[me->statepos - 1].state);
+    int special = FALSE, gotspecial = FALSE, ret = 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 */
+	goto done;		       /* never animate */
     } else if (button == 'u' || button == 'u' ||
                button == '\x1A' || button == '\x1F') {
 	midend_stop_anim(me);
+        special = me->states[me->statepos-1].special;
+        gotspecial = TRUE;
 	if (!midend_undo(me))
-            return 1;
-    } else if (button == '\x12') {
+	    goto done;
+    } else if (button == 'r' || button == 'R' ||
+               button == '\x12' || button == '\x19') {
 	midend_stop_anim(me);
 	if (!midend_redo(me))
-            return 1;
+            goto done;
     } else if (button == 'q' || button == 'Q' || button == '\x11') {
-	me->ourgame->free_game(oldstate);
-        return 0;
+	ret = 0;
+	goto done;
     } else {
-        game_state *s = me->ourgame->make_move(me->states[me->statepos-1],
-					       me->ui, x, y, button);
+        game_state *s =
+            me->ourgame->make_move(me->states[me->statepos-1].state,
+                                   me->ui, me->drawstate, x, y, button);
 
-        if (s == me->states[me->statepos-1]) {
+        if (s == me->states[me->statepos-1].state) {
             /*
              * 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;
+            goto done;
         } else if (s) {
 	    midend_stop_anim(me);
             while (me->nstates > me->statepos)
-                me->ourgame->free_game(me->states[--me->nstates]);
+                me->ourgame->free_game(me->states[--me->nstates].state);
             ensure(me);
-            me->states[me->nstates] = s;
+            me->states[me->nstates].state = s;
+            me->states[me->nstates].special = FALSE;   /* normal move */
             me->statepos = ++me->nstates;
             me->dir = +1;
         } else {
-            me->ourgame->free_game(oldstate);
-            return 1;
+          goto done;
         }
     }
 
+    if (!gotspecial)
+        special = me->states[me->statepos-1].special;
+
     /*
      * See if this move requires an animation.
      */
-    anim_time = me->ourgame->anim_length(oldstate, me->states[me->statepos-1],
-					 me->dir);
+    if (special) {
+        anim_time = 0;
+    } else {
+        anim_time = me->ourgame->anim_length(oldstate,
+                                             me->states[me->statepos-1].state,
+                                             me->dir, me->ui);
+    }
 
-    me->oldstate = oldstate;
+    me->oldstate = oldstate; oldstate = NULL;
     if (anim_time > 0) {
         me->anim_time = anim_time;
     } else {
@@ -262,9 +418,11 @@ static int midend_really_process_key(midend_data *me, int x, int y, int button)
 
     midend_redraw(me);
 
-    activate_timer(me->frontend);
+    midend_set_timer(me);
 
-    return 1;
+    done:
+    if (oldstate) me->ourgame->free_game(oldstate);
+    return ret;
 }
 
 int midend_process_key(midend_data *me, int x, int y, int button)
@@ -328,6 +486,14 @@ int midend_process_key(midend_data *me, int x, int y, int button)
      *    pressed, invent a button-up for the first one and then
      *    pass the button-down through as before.
      * 
+     * 2005-05-31: An addendum to the above. Some games might want
+     * a `priority order' among buttons, such that if one button is
+     * pressed while another is down then a fixed one of the
+     * buttons takes priority no matter what order they're pressed
+     * in. Mines, in particular, wants to treat a left+right click
+     * like a left click for the benefit of users of other
+     * implementations. So the last of the above points is modified
+     * in the presence of an (optional) button priority order.
      */
     if (IS_MOUSE_DRAG(button) || IS_MOUSE_RELEASE(button)) {
         if (me->pressed_mouse_button) {
@@ -341,6 +507,14 @@ int midend_process_key(midend_data *me, int x, int y, int button)
         } else
             return ret;                /* ignore it */
     } else if (IS_MOUSE_DOWN(button) && me->pressed_mouse_button) {
+	/*
+	 * If the new button has lower priority than the old one,
+	 * don't bother doing this.
+	 */
+	if (me->ourgame->mouse_priorities &
+	    BUTTON_BEATS(me->pressed_mouse_button, button))
+	    return ret;		       /* just ignore it */
+
         /*
          * Fabricate a button-up for the previously pressed button.
          */
@@ -373,11 +547,11 @@ void midend_redraw(midend_data *me)
             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->states[me->statepos-1].state, 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->states[me->statepos-1].state, +1 /*shrug*/,
 				me->ui, 0.0, me->flash_pos);
         }
         end_draw(me->frontend);
@@ -392,13 +566,22 @@ void midend_timer(midend_data *me, float tplus)
 	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);
+
+    if (me->timing) {
+	float oldelapsed = me->elapsed;
+	me->elapsed += tplus;
+	if ((int)oldelapsed != (int)me->elapsed)
+	    status_bar(me->frontend, me->laststatus ? me->laststatus : "");
+    }
+
+    midend_set_timer(me);
 }
 
 float *midend_colours(midend_data *me, int *ncolours)
@@ -408,16 +591,43 @@ float *midend_colours(midend_data *me, int *ncolours)
 
     if (me->nstates == 0) {
 	game_aux_info *aux = NULL;
-        char *seed = me->ourgame->new_seed(me->params, me->random, &aux);
-        state = me->ourgame->new_game(me->params, seed);
-        sfree(seed);
+        char *desc = me->ourgame->new_desc(me->params, me->random,
+					   &aux, TRUE);
+        state = me->ourgame->new_game(me, me->params, desc);
+        sfree(desc);
 	if (aux)
 	    me->ourgame->free_aux_info(aux);
     } else
-        state = me->states[0];
+        state = me->states[0].state;
 
     ret = me->ourgame->colours(me->frontend, state, ncolours);
 
+    {
+        int i;
+
+        /*
+         * Allow environment-based overrides for the standard
+         * colours by defining variables along the lines of
+         * `NET_COLOUR_4=6000c0'.
+         */
+
+        for (i = 0; i < *ncolours; i++) {
+            char buf[80], *e;
+            unsigned int r, g, b;
+            int j;
+
+            sprintf(buf, "%s_COLOUR_%d", me->ourgame->name, i);
+            for (j = 0; buf[j]; j++)
+                buf[j] = toupper((unsigned char)buf[j]);
+            if ((e = getenv(buf)) != NULL &&
+                sscanf(e, "%2x%2x%2x", &r, &g, &b) == 3) {
+                ret[i*3 + 0] = r / 255.0;
+                ret[i*3 + 1] = g / 255.0;
+                ret[i*3 + 2] = b / 255.0;
+            }
+        }
+    }
+
     if (me->nstates == 0)
         me->ourgame->free_game(state);
 
@@ -445,6 +655,59 @@ int midend_num_presets(midend_data *me)
         }
     }
 
+    {
+        /*
+         * Allow environment-based extensions to the preset list by
+         * defining a variable along the lines of `SOLO_PRESETS=2x3
+         * Advanced:2x3da'. Colon-separated list of items,
+         * alternating between textual titles in the menu and
+         * encoded parameter strings.
+         */
+        char buf[80], *e, *p;
+        int j;
+
+        sprintf(buf, "%s_PRESETS", me->ourgame->name);
+        for (j = 0; buf[j]; j++)
+            buf[j] = toupper((unsigned char)buf[j]);
+
+        if ((e = getenv(buf)) != NULL) {
+            p = e = dupstr(e);
+
+            while (*p) {
+                char *name, *val;
+                game_params *preset;
+
+                name = p;
+                while (*p && *p != ':') p++;
+                if (*p) *p++ = '\0';
+                val = p;
+                while (*p && *p != ':') p++;
+                if (*p) *p++ = '\0';
+
+                preset = me->ourgame->default_params();
+                me->ourgame->decode_params(preset, val);
+
+		if (me->ourgame->validate_params(preset)) {
+		    /* Drop this one from the list. */
+		    me->ourgame->free_params(preset);
+		    continue;
+		}
+
+                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;
 }
 
@@ -461,35 +724,64 @@ int midend_wants_statusbar(midend_data *me)
     return me->ourgame->wants_statusbar();
 }
 
+void midend_supersede_game_desc(midend_data *me, char *desc)
+{
+    sfree(me->desc);
+    me->desc = dupstr(desc);
+}
+
 config_item *midend_get_config(midend_data *me, int which, char **wintitle)
 {
-    char *titlebuf, *parstr;
+    char *titlebuf, *parstr, *rest;
     config_item *ret;
+    char sep;
 
+    assert(wintitle);
     titlebuf = snewn(40 + strlen(me->ourgame->name), char);
 
     switch (which) {
       case CFG_SETTINGS:
 	sprintf(titlebuf, "%s configuration", me->ourgame->name);
-	*wintitle = dupstr(titlebuf);
+	*wintitle = titlebuf;
 	return me->ourgame->configure(me->params);
       case CFG_SEED:
-	sprintf(titlebuf, "%s game selection", me->ourgame->name);
-	*wintitle = dupstr(titlebuf);
+      case CFG_DESC:
+        if (!me->curparams) {
+          sfree(titlebuf);
+          return NULL;
+        }
+        sprintf(titlebuf, "%s %s selection", me->ourgame->name,
+                which == CFG_SEED ? "random" : "game");
+        *wintitle = titlebuf;
 
 	ret = snewn(2, config_item);
 
 	ret[0].type = C_STRING;
-	ret[0].name = "Game ID";
+        if (which == CFG_SEED)
+            ret[0].name = "Game random seed";
+        else
+            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.
+         * For CFG_DESC the text going in here will be a string
+         * encoding of the restricted parameters, plus a colon,
+         * plus the game description. For CFG_SEED it will be the
+         * full parameters, plus a hash, plus the random seed data.
+         * Either of these is a valid full game ID (although only
+         * the former is likely to persist across many code
+         * changes).
          */
-        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);
+        parstr = me->ourgame->encode_params(me->curparams, which == CFG_SEED);
+        assert(parstr);
+        if (which == CFG_DESC) {
+            rest = me->desc ? me->desc : "";
+            sep = ':';
+        } else {
+            rest = me->seedstr ? me->seedstr : "";
+            sep = '#';
+        }
+        ret[0].sval = snewn(strlen(parstr) + strlen(rest) + 2, char);
+        sprintf(ret[0].sval, "%s%c%s", parstr, sep, rest);
         sfree(parstr);
 
 	ret[1].type = C_END;
@@ -503,62 +795,107 @@ config_item *midend_get_config(midend_data *me, int which, char **wintitle)
     return NULL;
 }
 
-char *midend_game_id(midend_data *me, char *id, int def_seed)
+static char *midend_game_id_int(midend_data *me, char *id, int defmode)
 {
-    char *error, *par, *seed;
-    game_params *params;
+    char *error, *par, *desc, *seed;
 
-    seed = strchr(id, ':');
+    seed = strchr(id, '#');
+    desc = strchr(id, ':');
 
-    if (seed) {
+    if (desc && (!seed || desc < seed)) {
         /*
-         * We have a colon separating parameters from game seed. So
-         * `par' now points to the parameters string, and `seed' to
-         * the seed string.
+         * We have a colon separating parameters from game
+         * description. So `par' now points to the parameters
+         * string, and `desc' to the description string.
+         */
+        *desc++ = '\0';
+        par = id;
+        seed = NULL;
+    } else if (seed && (!desc || seed < desc)) {
+        /*
+         * We have a hash separating parameters from random seed.
+         * So `par' now points to the parameters string, and `seed'
+         * to the seed string.
          */
         *seed++ = '\0';
         par = id;
+        desc = NULL;
     } else {
         /*
-         * We only have one string. Depending on `def_seed', we
-         * take it to be either parameters or seed.
+         * We only have one string. Depending on `defmode', we take
+         * it to be either parameters, seed or description.
          */
-        if (def_seed) {
+        if (defmode == DEF_SEED) {
             seed = id;
-            par = NULL;
+            par = desc = NULL;
+        } else if (defmode == DEF_DESC) {
+            desc = id;
+            par = seed = NULL;
         } else {
-            seed = NULL;
             par = id;
+            seed = desc = NULL;
         }
     }
 
     if (par) {
-        params = me->ourgame->decode_params(par);
-        error = me->ourgame->validate_params(params);
+        game_params *tmpparams;
+        tmpparams = me->ourgame->dup_params(me->params);
+        me->ourgame->decode_params(tmpparams, par);
+        error = me->ourgame->validate_params(tmpparams);
         if (error) {
-            me->ourgame->free_params(params);
+            me->ourgame->free_params(tmpparams);
             return error;
         }
-        me->ourgame->free_params(me->params);
-        me->params = params;
+        if (me->curparams)
+            me->ourgame->free_params(me->curparams);
+        me->curparams = tmpparams;
+
+        /*
+         * Now filter only the persistent parts of this state into
+         * the long-term params structure, unless we've _only_
+         * received a params string in which case the whole lot is
+         * persistent.
+         */
+        if (seed || desc) {
+            char *tmpstr = me->ourgame->encode_params(tmpparams, FALSE);
+            me->ourgame->decode_params(me->params, tmpstr);
+            sfree(tmpstr);
+        } else {
+            me->ourgame->free_params(me->params);
+            me->params = me->ourgame->dup_params(tmpparams);
+        }
     }
 
-    if (seed) {
-        error = me->ourgame->validate_seed(me->params, seed);
+    sfree(me->desc);
+    me->desc = NULL;
+    sfree(me->seedstr);
+    me->seedstr = NULL;
+
+    if (desc) {
+        error = me->ourgame->validate_desc(me->params, desc);
         if (error)
             return error;
 
-        sfree(me->seed);
-        me->seed = dupstr(seed);
-        me->fresh_seed = TRUE;
+        me->desc = dupstr(desc);
+        me->genmode = GOT_DESC;
 	if (me->aux_info)
 	    me->ourgame->free_aux_info(me->aux_info);
 	me->aux_info = NULL;
     }
 
+    if (seed) {
+        me->seedstr = dupstr(seed);
+        me->genmode = GOT_SEED;
+    }
+
     return NULL;
 }
 
+char *midend_game_id(midend_data *me, char *id)
+{
+    return midend_game_id_int(me, id, DEF_PARAMS);
+}
+
 char *midend_set_config(midend_data *me, int which, config_item *cfg)
 {
     char *error;
@@ -579,7 +916,9 @@ char *midend_set_config(midend_data *me, int which, config_item *cfg)
 	break;
 
       case CFG_SEED:
-        error = midend_game_id(me, cfg[0].sval, TRUE);
+      case CFG_DESC:
+        error = midend_game_id_int(me, cfg[0].sval,
+                                   (which == CFG_SEED ? DEF_SEED : DEF_DESC));
 	if (error)
 	    return error;
 	break;
@@ -591,7 +930,76 @@ char *midend_set_config(midend_data *me, int which, config_item *cfg)
 char *midend_text_format(midend_data *me)
 {
     if (me->ourgame->can_format_as_text && me->statepos > 0)
-	return me->ourgame->text_format(me->states[me->statepos-1]);
+	return me->ourgame->text_format(me->states[me->statepos-1].state);
     else
 	return NULL;
 }
+
+char *midend_solve(midend_data *me)
+{
+    game_state *s;
+    char *msg;
+
+    if (!me->ourgame->can_solve)
+	return "This game does not support the Solve operation";
+
+    if (me->statepos < 1)
+	return "No game set up to solve";   /* _shouldn't_ happen! */
+
+    msg = "Solve operation failed";    /* game _should_ overwrite on error */
+    s = me->ourgame->solve(me->states[0].state,
+			   me->states[me->statepos-1].state,
+			   me->aux_info, &msg);
+    if (!s)
+	return msg;
+
+    /*
+     * Now enter the solved state as the next move.
+     */
+    midend_stop_anim(me);
+    while (me->nstates > me->statepos)
+	me->ourgame->free_game(me->states[--me->nstates].state);
+    ensure(me);
+    me->states[me->nstates].state = s;
+    me->states[me->nstates].special = TRUE;   /* created using solve */
+    me->statepos = ++me->nstates;
+    if (me->ui)
+        me->ourgame->changed_state(me->ui,
+                                   me->states[me->statepos-2].state,
+                                   me->states[me->statepos-1].state);
+    me->anim_time = 0.0;
+    midend_finish_move(me);
+    midend_redraw(me);
+    midend_set_timer(me);
+    return NULL;
+}
+
+char *midend_rewrite_statusbar(midend_data *me, char *text)
+{
+    /*
+     * An important special case is that we are occasionally called
+     * with our own laststatus, to update the timer.
+     */
+    if (me->laststatus != text) {
+	sfree(me->laststatus);
+	me->laststatus = dupstr(text);
+    }
+
+    if (me->ourgame->is_timed) {
+	char timebuf[100], *ret;
+	int min, sec;
+
+	sec = me->elapsed;
+	min = sec / 60;
+	sec %= 60;
+	sprintf(timebuf, "[%d:%02d] ", min, sec);
+
+	ret = snewn(strlen(timebuf) + strlen(text) + 1, char);
+	strcpy(ret, timebuf);
+	strcat(ret, text);
+	return ret;
+
+    } else {
+	return dupstr(text);
+    }
+}