+static void
+mnemon_handle_command (mnemon_t *mnemon,
+ const char *command)
+{
+ const char *arg;
+ int len;
+ switch (command[0]) {
+ case 'h':
+ {
+ char *category = NULL;
+ int length = 0;
+
+ arg = command + 1;
+ arg += strspn (arg, " \t");
+ len = strcspn (arg, " \t");
+ if (len) {
+ category = xstrndup (arg, len);
+ arg += len;
+ arg += strspn (arg, " \t");
+ if (*arg)
+ length = atoi (arg);
+ }
+ mnemon_print_histogram (mnemon, category, length);
+ }
+ break;
+ default:
+ printf ("Unknown command: %s\n", command);
+ break;
+ }
+}
+
+static void
+mnemon_handle_response (mnemon_t *mnemon,
+ bin_t *bin,
+ int item_index,
+ item_t *item,
+ const char *response,
+ double response_time,
+ double time_limit)
+{
+ bool_t correct;
+
+ correct = (strcmp (response, item->response) == 0);
+
+ bin_remove_item (bin, item_index);
+
+ /* If the bin is now empty, we must remove it. Also if we just
+ * picked the last word we'll ever pick from the bin with
+ * score 0, then we can remove that as well. */
+ if (bin->num_items == 0 ||
+ (bin->score == 0 && mnemon->to_introduce == 0))
+ {
+ mnemon_remove_bin (mnemon, bin);
+ }
+
+ if (correct &&
+ (time_limit == 0.0 || response_time < time_limit))
+ {
+ item->score++;
+ mnemon->to_master--;
+ /* We reserve an item score of 0 for an item that has
+ * never been asked. */
+ if (item->score == 0) {
+ item->score = 1;
+ mnemon->unlearned--;
+ mnemon->to_master--;
+ printf ("You got it!");
+ } else if (item->score < 0) {
+ printf ("Yes---just give me %d more.",
+ - item->score);
+ } else if (item->score == 1) {
+ printf ("On your first try, no less!");
+ } else {
+ printf ("Masterful (%dx).", item->score);
+ }
+ } else {
+ if (! correct)
+ printf (" %s is the correct answer.",
+ item->response);
+ else
+ printf ("Correct, but not quite quick enough (%0.2f seconds---needed %0.2f seconds)\n",
+ response_time, time_limit);
+ /* Penalize an incorrect response by forcing the score
+ * negative. */
+ if (item->score >= 0) {
+ if (item->score > 0)
+ printf (" Oops, you knew that, right? (%dx)\n ",
+ item->score);
+ mnemon->unlearned++;
+ /* We add three here, (rather than just 2 to track the
+ * change in the item's score below), as an extra
+ * penalty. If the user is forgetting stuff learned
+ * previously, then more time should be spent on mastering
+ * than learning new items. */
+ mnemon->to_master += item->score + 3;
+ /* We go to -2 to force a little extra reinforcement
+ * when re-learning an item, (otherwise, it will often
+ * get asked again immediately where it is easy to get
+ * a correct response without any learning). */
+ item->score = -2;
+ } else {
+ item->score--;
+ mnemon->to_master++;
+ }
+ }
+
+ printf (" ");
+ if (mnemon->to_introduce)
+ printf ("%d to come. ", mnemon->to_introduce);
+ if (mnemon->unlearned)
+ printf ("%d still unlearned. ", mnemon->unlearned);
+ if (mnemon->to_introduce == 0 && mnemon->to_master > 0)
+ printf ("%d items to master", mnemon->to_master);
+ printf ("\n\n");
+
+ bin = mnemon_get_bin (mnemon, item->score);
+
+ bin_add_item (bin, item);
+}
+
+static void
+mnemon_show_challenge (mnemon_t *mnemon,
+ challenge_type_t challenge_type,
+ const char *challenge)
+{
+ const char *program;
+ char *command;
+
+ if (challenge_type == CHALLENGE_TYPE_TEXT) {
+ printf ("%s\n", challenge);
+ return;
+ }
+
+ /* XXX: Yes, shelling out to system is total cheese. The planned
+ * fix here is to bring graphical display in process, (or at least
+ * have a custom external program that accepts image filenames on
+ * stdin.
+ */
+ switch (challenge_type) {
+ case CHALLENGE_TYPE_TEXT:
+ ASSERT_NOT_REACHED;
+ break;
+ case CHALLENGE_TYPE_IMAGE:
+ program = "xli -gamma 2.2";
+ break;
+ case CHALLENGE_TYPE_AUDIO:
+ program = "play";
+ break;
+ }
+
+ xasprintf (&command, "%s %s/%s >/dev/null 2>&1 &",
+ program,
+ mnemon->dir_name,
+ challenge);
+ system (command);
+ free (command);
+}
+
+static void
+mnemon_hide_challenge (mnemon_t *mnemon, challenge_type_t challenge_type)
+{
+ char * command;
+
+ if (challenge_type != CHALLENGE_TYPE_IMAGE)
+ return;
+
+ /* XXX: And this is just embarrassing (obviously wrong in several
+ * ways). Hopefully I'll amend away any commit that includes this.
+ */
+ xasprintf (&command, "killall xli");
+ system (command);
+ free (command);
+}
+
+static void
+mnemon_do_challenges (mnemon_t *mnemon)
+{
+ bin_t *bin;
+ int item_index;
+ item_t *item;
+ category_t *category;
+ char *response;
+ int i;
+
+ /* Count the number of items with negative scores. */
+ mnemon->unlearned = 0;
+ for (i = 0; i < mnemon->num_bins; i++) {
+ bin = &mnemon->bins[i];
+ if (bin->score >= 0)
+ break;
+ mnemon->unlearned += bin->num_items;
+ }
+
+ mnemon->to_introduce -= mnemon->unlearned;
+ if (mnemon->to_introduce < 0)
+ mnemon->to_introduce = 0;
+
+ /* Get rid of bin with score of 0 if we aren't going to be
+ * introducing anything from it. */
+ if (mnemon->to_introduce == 0) {
+ bin = mnemon_get_bin (mnemon, 0);
+ mnemon_remove_bin (mnemon, bin);
+ }
+
+ if (mnemon->unlearned) {
+ printf ("You've got %d items to learn already. ", mnemon->unlearned);
+ if (mnemon->to_introduce)
+ printf ("I'll introduce %d more as we go.", mnemon->to_introduce);
+ printf ("\n");
+ } else {
+ printf ("Introducing %d new items.\n", mnemon->to_introduce);
+ }
+ printf ("\n");
+
+ do {
+ struct timeval start, end;
+
+ mnemon_select_item (mnemon, &bin, &item_index, &category);
+ item = bin->items[item_index];
+
+ while (1) {
+ if (category->time_limit > 0.0) {
+ response = readline ("The next one is timed. Press enter when ready:");
+ free (response);
+ }
+
+ mnemon_show_challenge (mnemon, category->challenge_type,
+ item->challenge);
+
+ gettimeofday (&start, NULL);
+ response = readline ("> ");
+ gettimeofday (&end, NULL);
+
+ mnemon_hide_challenge (mnemon, category->challenge_type);
+
+ /* Terminate on EOF */
+ if (response == NULL) {
+ printf ("\n");
+ return;
+ }
+
+ if (response[0] == '/') {
+ mnemon_handle_command (mnemon, response + 1);
+ free (response);
+ } else {
+ break;
+ }
+ }
+
+ mnemon_handle_response (mnemon, bin, item_index,
+ item, response,
+ (end.tv_sec + end.tv_usec / 1e6) -
+ (start.tv_sec + start.tv_usec / 1e6),
+ category->time_limit);
+ free (response);
+
+ /* Replay audio challenges for reinforcement. */
+ if (category->challenge_type == CHALLENGE_TYPE_AUDIO) {
+ mnemon_show_challenge (mnemon, category->challenge_type,
+ item->challenge);
+ sleep (1);
+ }
+ } while (mnemon->to_introduce ||
+ mnemon->unlearned ||
+ mnemon->to_master > 0);
+}
+