Improve the highscore related functions in plugin lib (FS#10350)

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21578 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 95 insertions, 55 deletions

diff --git a/apps/plugins/lib/highscore.c b/apps/plugins/lib/highscore.c
index 9d3b19ea48..e8e1c883b0 100644
--- a/apps/plugins/lib/highscore.c
+++ b/apps/plugins/lib/highscore.c
@@ -34,8 +34,8 @@ int highscore_save(char *filename, struct highscore *scores, int num_scores)
     
     for(i = 0;i < num_scores;i++)
     {
-        rb->snprintf(buf, sizeof(buf)-1, "%s:%d:%d\n",
-                     scores[i].name, scores[i].score, scores[i].level);
+        rb->snprintf(buf, sizeof(buf), "%d:%d:%s\n",
+                     scores[i].score, scores[i].level, scores[i].name);
         rc = rb->write(fd, buf, rb->strlen(buf));
         if(rc < 0)
         {
@@ -52,72 +52,62 @@ int highscore_load(char *filename, struct highscore *scores, int num_scores)
     int i;
     int fd;
     char buf[80];
-    char *name, *score, *level;
-    char *ptr;
+    char *score, *level, *name;
 
-    fd = rb->open(filename, O_RDONLY);
+    rb->memset(scores, 0, sizeof(struct highscore)*num_scores);
 
-    rb->memset(scores, 0, sizeof(struct highscore)*(num_scores+1));
-    
+    fd = rb->open(filename, O_RDONLY);
     if(fd < 0)
         return -1;
 
-    i = -1;
-    while(rb->read_line(fd, buf, sizeof(buf)-1) && i < num_scores)
+    i = 0;
+    while(rb->read_line(fd, buf, sizeof(buf)) > 0 && i < num_scores)
     {
-        i++;
-        
         DEBUGF("%s\n", buf);
-        name = buf;
-        ptr = rb->strchr(buf, ':');
-        if ( !ptr )
+
+        if ( !rb->settings_parseline(buf, &score, &level) )
             continue;
-        *ptr = 0;
-        ptr++;
-        
-        rb->strncpy(scores[i].name, name, sizeof(scores[i].name));
-        
-        DEBUGF("%s\n", scores[i].name);
-        score = ptr;
-        
-        ptr = rb->strchr(ptr, ':');
-        if ( !ptr )
+        if ( !rb->settings_parseline(level, &level, &name) )
             continue;
-        *ptr = 0;
-        ptr++;
-        
+
         scores[i].score = rb->atoi(score);
-        
-        level = ptr;
         scores[i].level = rb->atoi(level);
-    }    
+        rb->strncpy(scores[i].name, name, sizeof(scores[i].name)-1);
+        i++;
+    }
+    rb->close(fd);
     return 0;
 }
 
-int highscore_update(int score, int level, struct highscore *scores, int num_scores)
+int highscore_update(int score, int level, const char *name,
+                     struct highscore *scores, int num_scores)
 {
-        int i, j;
-        int new = 0;
-        
-        /* look through the scores and see if this one is in the top ones */
-        for(i = num_scores-1;i >= 0; i--)
+    int pos;
+    struct highscore *entry;
+    
+    if (!highscore_would_update(score, scores, num_scores))
+        return -1;
+
+    pos = num_scores-1;
+    while (pos > 0 && score > scores[pos-1].score)
     {
-                if ((score > scores[i].score))
-                {
-                        /* Move the rest down one... */
-                        if (i > 0)
-                        {
-                                for (j=1; j<=i; j++)
-                                {
-                                        rb->memcpy((void *)&scores[j-1], (void *)&scores[j], sizeof(struct highscore));
-                                }
-                        }
-                        scores[i].score = score;
-                        scores[i].level = level;
-                        /* Need to sort out entering a name... maybe old three letter arcade style */
-                        new = 1;
-                        break;
-                }
-        }
-        return new;
+        /* move down one */
+        rb->memcpy((void *)&scores[pos], (void *)&scores[pos-1],
+                   sizeof(struct highscore));
+        pos--;
+    }
+    
+    entry = scores + pos;
+    entry->score = score;
+    entry->level = level;
+    rb->strncpy(entry->name, name, sizeof(entry->name));
+    entry->name[sizeof(entry->name)-1] = '\0';
+
+    return pos;
+}
+
+bool highscore_would_update(int score, struct highscore *scores,
+                            int num_scores)
+{
+    return (num_scores > 0) && (score > scores[num_scores-1].score);
 }
diff --git a/apps/plugins/lib/highscore.h b/apps/plugins/lib/highscore.h
index db09172c7d..a38a6f7bf3 100644
--- a/apps/plugins/lib/highscore.h
+++ b/apps/plugins/lib/highscore.h
@@ -21,6 +21,8 @@
 #ifndef HIGHSCORE_H
 #define HIGHSCORE_H
 
+/* see rockblox.c for the example of usage. */
+
 struct highscore
 {
     char name[32];
@@ -28,8 +30,56 @@ struct highscore
     int level;
 };
 
+/* Saves the scores to a file
+ *   - filename: name of the file to write the data to
+ *   - scores  : scores to store
+ *   - num_scores: number of the elements in the array 'scores'
+ * Returns 0 on success or a negative value if an error occures
+ */
 int highscore_save(char *filename, struct highscore *scores, int num_scores);
+
+/* Reads the scores from a file. The file must be a text file, each line
+ * represents a score entry.
+ *
+ *   - filename: name of the file to read the data from
+ *   - scores  : where to put the read data
+ *   - num_scores: max number of the scores to read (array capacity)
+ *
+ * Returns 0 on success or a negative value if an error occures
+ */
 int highscore_load(char *filename, struct highscore *scores, int num_scores);
-int highscore_update(int score, int level, struct highscore *scores, int num_scores);
+
+/* Inserts score and level into array of struct highscore in the
+ * descending order of scores, i.e. higher scores are at lower array
+ * indexes.
+ *
+ *   - score : the new score value to insert
+ *   - level : the game level at which the score was reached
+ *   - name  : the name of the new entry (whatever it means)
+ *   - scores: the array of scores to insert the new value into
+ *   - num_scores: number of elements in 'scores'
+ *
+ * Returns the 0-based position of the newly inserted score if it was
+ * inserted. Returns a negative value if the score was not inserted
+ * (i.e. it was less than the lowest score in the array).
+ */
+int highscore_update(int score, int level, const char *name,
+                     struct highscore *scores, int num_scores);
+
+/* Checks whether the new score would be inserted into the score table.
+ * This function can be used to find out whether a score with the given
+ * value would be inserted into the score table. If yes, the program
+ * can collect the name of the entry from the user (if it's done that
+ * way) and then really update the score table with 'highscore_update'.
+ *
+ *   - score : the score value to check
+ *   - scores: the array of existing scores
+ *   - num_scores: number of elements in 'scores'
+ *
+ * Returns true iff the given score would be inserted into the score
+ * table by highscore_update.
+ */
+bool highscore_would_update(int score, struct highscore *scores,
+                            int num_scores);
 
 #endif