core: add reverse of string for screen in evaluation of expressions with "revscr:"

4 files changed, 66 insertions, 4 deletions

diff --git a/src/core/wee-command.c b/src/core/wee-command.c
index f1d1b43bf..85939a89c 100644
--- a/src/core/wee-command.c
+++ b/src/core/wee-command.c
@@ -7353,7 +7353,7 @@ command_init ()
            "     or max chars displayed on screen "
            "(format: \"cutscr:max,suffix,string\" or "
            "\"cutscr:+max,suffix,string\")\n"
-           "  5. a reversed string (format: \"rev:xxx\")\n"
+           "  5. a reversed string (format: \"rev:xxx\" or \"revscr:xxx\")\n"
            "  6. a repeated string (format: \"repeat:count,string\")\n"
            "  7. length of a string (format: \"length:xxx\" or "
            "\"lengthscr:xxx\")\n"
diff --git a/src/core/wee-eval.c b/src/core/wee-eval.c
index ab9cc8405..1bcd96a4b 100644
--- a/src/core/wee-eval.c
+++ b/src/core/wee-eval.c
@@ -295,7 +295,8 @@ end:
  *   5. a string with max chars (format: cut:max,suffix,string or
  *      cut:+max,suffix,string) or max chars on screen
  *      (format: cutscr:max,suffix,string or cutscr:+max,suffix,string)
- *   6. a reversed string (format: rev:xxx)
+ *   6. a reversed string (format: rev:xxx) or reversed string for screen,
+ *      color codes are not reversed (format: revscr:xxx)
  *   7. a repeated string (format: repeat:count,string)
  *   8. length of a string (format: length:xxx) or length of a string on screen
  *      (format: lengthscr:xxx); color codes are ignored
@@ -459,9 +460,9 @@ eval_replace_vars_cb (void *data, const char *text)
 
     /* 6. reverse string */
     if (strncmp (text, "rev:", 4) == 0)
-    {
         return string_reverse (text + 4);
-    }
+    if (strncmp (text, "revscr:", 7) == 0)
+        return string_reverse_screen (text + 7);
 
     /* 7. repeated string */
     if (strncmp (text, "repeat:", 7) == 0)
diff --git a/src/core/wee-string.c b/src/core/wee-string.c
index 5025958a1..3b082d57f 100644
--- a/src/core/wee-string.c
+++ b/src/core/wee-string.c
@@ -204,6 +204,66 @@ string_reverse (const char *string)
 }
 
 /*
+ * Reverses a string for screen: color codes are not reversed.
+ * For example: reverse of "<red>test" is "test<red>" where the color code
+ * "<red>" is kept as-is, so it is still valid (this is not the case with
+ * function string_reverse).
+ *
+ * Note: result must be freed after use.
+ */
+
+char *
+string_reverse_screen (const char *string)
+{
+    int length, color_size, char_size;
+    const char *ptr_string, *ptr_next;
+    char *result, *ptr_result;
+
+    if (!string)
+        return NULL;
+
+    if (!string[0])
+        return strdup (string);
+
+    length = strlen (string);
+    result = malloc (length + 1);
+    if (!result)
+        return NULL;
+
+    ptr_string = string;
+    ptr_result = result + length;
+    ptr_result[0] = '\0';
+
+    while (ptr_string && ptr_string[0])
+    {
+        ptr_next = gui_chat_string_next_char (NULL, NULL,
+                                              (const unsigned char *)ptr_string,
+                                              0, 0, 0);
+        if (!ptr_next)
+            ptr_next = ptr_string + strlen (ptr_string);
+        color_size = ptr_next - ptr_string;
+        if (color_size > 0)
+        {
+            /* add the color code as-is */
+            ptr_result -= color_size;
+            memcpy (ptr_result, ptr_string, color_size);
+            ptr_string += color_size;
+        }
+
+        if (ptr_string[0])
+        {
+            char_size = utf8_char_size (ptr_string);
+
+            ptr_result -= char_size;
+            memcpy (ptr_result, ptr_string, char_size);
+            ptr_string += char_size;
+        }
+    }
+
+    return result;
+}
+
+/*
  * Repeats a string a given number of times.
  *
  * Note: result must be freed after use.
diff --git a/src/core/wee-string.h b/src/core/wee-string.h
index ef34af417..7eaef061e 100644
--- a/src/core/wee-string.h
+++ b/src/core/wee-string.h
@@ -40,6 +40,7 @@ extern char *string_strndup (const char *string, int length);
 extern char *string_cut (const char *string, int length, int count_suffix,
                          int screen, const char *cut_suffix);
 extern char *string_reverse (const char *string);
+extern char *string_reverse_screen (const char *string);
 extern char *string_repeat (const char *string, int count);
 extern void string_tolower (char *string);
 extern void string_toupper (char *string);