core: add ternary operator (condition) in evaluation of expressions

4 files changed, 198 insertions, 77 deletions

diff --git a/src/core/wee-command.c b/src/core/wee-command.c
index be8e0f759..a6f03f3c0 100644
--- a/src/core/wee-command.c
+++ b/src/core/wee-command.c
@@ -7273,9 +7273,11 @@ command_init ()
            "optional)\n"
            "  6. current date/time (format: \"date\" or \"date:format\")\n"
            "  7. an environment variable (format: \"env:XXX\")\n"
-           "  8. an option (format: \"file.section.option\")\n"
-           "  9. a local variable in buffer\n"
-           "  10. a hdata name/variable (the value is automatically converted "
+           "  8. a ternary operator (format: "
+           "if:condition?value_if_true:value_if_false)\n"
+           "  9. an option (format: \"file.section.option\")\n"
+           "  10. a local variable in buffer\n"
+           "  11. a hdata name/variable (the value is automatically converted "
            "to string), by default \"window\" and \"buffer\" point to current "
            "window/buffer.\n"
            "Format for hdata can be one of following:\n"
@@ -7295,16 +7297,17 @@ command_init ()
            "reference\", function \"weechat_hdata_get\".\n"
            "\n"
            "Examples (simple strings):\n"
-           "  /eval -n ${info:version}                     ==> 0.4.3\n"
-           "  /eval -n ${env:HOME}                         ==> /home/user\n"
-           "  /eval -n ${weechat.look.scroll_amount}       ==> 3\n"
-           "  /eval -n ${window}                           ==> 0x2549aa0\n"
-           "  /eval -n ${window.buffer}                    ==> 0x2549320\n"
-           "  /eval -n ${window.buffer.full_name}          ==> core.weechat\n"
-           "  /eval -n ${window.buffer.number}             ==> 1\n"
-           "  /eval -n ${\\t}                               ==> <tab>\n"
-           "  /eval -n ${hide:-,${relay.network.password}} ==> --------\n"
-           "  /eval -n ${date:%H:%M:%S}                    ==> 07:46:40\n"
+           "  /eval -n ${info:version}                       ==> 0.4.3\n"
+           "  /eval -n ${env:HOME}                           ==> /home/user\n"
+           "  /eval -n ${weechat.look.scroll_amount}         ==> 3\n"
+           "  /eval -n ${window}                             ==> 0x2549aa0\n"
+           "  /eval -n ${window.buffer}                      ==> 0x2549320\n"
+           "  /eval -n ${window.buffer.full_name}            ==> core.weechat\n"
+           "  /eval -n ${window.buffer.number}               ==> 1\n"
+           "  /eval -n ${\\t}                                 ==> <tab>\n"
+           "  /eval -n ${hide:-,${relay.network.password}}   ==> --------\n"
+           "  /eval -n ${date:%H:%M:%S}                      ==> 07:46:40\n"
+           "  /eval -n ${if:${info:term_width}>80?big:small} ==> big\n"
            "\n"
            "Examples (conditions):\n"
            "  /eval -n -c ${window.buffer.number} > 2 ==> 0\n"
diff --git a/src/core/wee-eval.c b/src/core/wee-eval.c
index 4a63b7ee4..eb332c8cd 100644
--- a/src/core/wee-eval.c
+++ b/src/core/wee-eval.c
@@ -49,10 +49,17 @@ char *logical_ops[EVAL_NUM_LOGICAL_OPS] =
 char *comparisons[EVAL_NUM_COMPARISONS] =
 { "=~", "!~", "==", "!=", "<=", "<", ">=", ">" };
 
+
 char *eval_replace_vars (const char *expr, struct t_hashtable *pointers,
                          struct t_hashtable *extra_vars, int extra_vars_eval,
                          const char *prefix, const char *suffix,
                          struct t_eval_regex *eval_regex);
+char *eval_expression_condition (const char *expr,
+                                 struct t_hashtable *pointers,
+                                 struct t_hashtable *extra_vars,
+                                 int extra_vars_eval,
+                                 const char *prefix,
+                                 const char *suffix);
 
 
 /*
@@ -71,6 +78,66 @@ eval_is_true (const char *value)
 }
 
 /*
+ * Searches a string in another at same level (skip sub-expressions between
+ * prefix/suffix).
+ *
+ * If escape is 1, the prefix can be escaped with '\' (and then is ignored).
+ *
+ * For example: eval_strstr_level ("(x || y) || z", "||")
+ * will return a pointer on  "|| z" (because the first "||" is
+ * in a sub-expression, which is skipped).
+ *
+ * Returns pointer to string found, or NULL if not found.
+ */
+
+const char *
+eval_strstr_level (const char *string, const char *search,
+                   const char *prefix, const char *suffix, int escape)
+{
+    const char *ptr_string;
+    int level, length_search, length_prefix, length_suffix;
+
+    if (!string || !search)
+        return NULL;
+
+    length_search = strlen (search);
+    length_prefix = strlen (prefix);
+    length_suffix = strlen (suffix);
+
+    ptr_string = string;
+    level = 0;
+    while (ptr_string[0])
+    {
+        if (escape && (ptr_string[0] == '\\') && (ptr_string[1] == prefix[0]))
+        {
+            ptr_string++;
+        }
+        else if (strncmp (ptr_string, prefix, length_prefix) == 0)
+        {
+            level++;
+            ptr_string += length_prefix;
+        }
+        else if (strncmp (ptr_string, suffix, length_suffix) == 0)
+        {
+            if (level > 0)
+                level--;
+            ptr_string += length_suffix;
+        }
+        else if ((level == 0)
+                 && (strncmp (ptr_string, search, length_search) == 0))
+        {
+            return ptr_string;
+        }
+        else
+        {
+            ptr_string++;
+        }
+    }
+
+    return NULL;
+}
+
+/*
  * Gets value of hdata using "path" to a variable.
  *
  * Note: result must be freed after use.
@@ -233,9 +300,10 @@ end:
  *   7. an info (format: info:name,arguments)
  *   8. current date/time (format: date or date:xxx)
  *   9. an environment variable (format: env:XXX)
- *  10. an option (format: file.section.option)
- *  11. a buffer local variable
- *  12. a hdata variable (format: hdata.var1.var2 or hdata[list].var1.var2
+ *  10. a ternary operator (format: if:condition?value_if_true:value_if_false)
+ *  11. an option (format: file.section.option)
+ *  12. a buffer local variable
+ *  13. a hdata variable (format: hdata.var1.var2 or hdata[list].var1.var2
  *                        or hdata[ptr].var1.var2)
  *
  * See /help in WeeChat for examples.
@@ -251,7 +319,7 @@ eval_replace_vars_cb (void *data, const char *text)
     struct t_config_option *ptr_option;
     struct t_gui_buffer *ptr_buffer;
     char str_value[512], *value, *pos, *pos1, *pos2, *hdata_name, *list_name;
-    char *tmp, *info_name, *hide_char, *hidden_string, *error;
+    char *tmp, *info_name, *hide_char, *hidden_string, *error, *condition;
     const char *prefix, *suffix, *ptr_value, *ptr_arguments, *ptr_string;
     struct t_hdata *hdata;
     void *pointer;
@@ -410,7 +478,71 @@ eval_replace_vars_cb (void *data, const char *text)
             return strdup (ptr_value);
     }
 
-    /* 10. option: if found, return this value */
+    /* 10: ternary operator: if:condition?value_if_true:value_if_false */
+    if (strncmp (text, "if:", 3) == 0)
+    {
+        value = NULL;
+        pos = (char *)eval_strstr_level (text + 3, "?", prefix, suffix, 1);
+        pos2 = (pos) ?
+            (char *)eval_strstr_level (pos + 1, ":", prefix, suffix, 1) : NULL;
+        condition = (pos) ?
+            strndup (text + 3, pos - (text + 3)) : strdup (text + 3);
+        if (!condition)
+            return strdup ("");
+        tmp = eval_expression_condition (condition, pointers,
+                                         extra_vars, extra_vars_eval,
+                                         prefix, suffix);
+        rc = (tmp && strcmp (tmp, "1") == 0);
+        if (tmp)
+            free (tmp);
+        if (rc)
+        {
+            /*
+             * condition is true: return the "value_if_true"
+             * (or EVAL_STR_TRUE if value is missing)
+             */
+            if (pos)
+            {
+                tmp = (pos2) ?
+                    strndup (pos + 1, pos2 - pos - 1) : strdup (pos + 1);
+                if (tmp)
+                {
+                    value = eval_replace_vars (tmp, pointers,
+                                               extra_vars, extra_vars_eval,
+                                               prefix, suffix,
+                                               eval_regex);
+                    free (tmp);
+                }
+            }
+            else
+            {
+                value = strdup (EVAL_STR_TRUE);
+            }
+        }
+        else
+        {
+            /*
+             * condition is false: return the "value_if_false"
+             * (or EVAL_STR_FALSE if both values are missing)
+             */
+            if (pos2)
+            {
+                value = eval_replace_vars (pos2 + 1, pointers,
+                                           extra_vars, extra_vars_eval,
+                                           prefix, suffix,
+                                           eval_regex);
+            }
+            else
+            {
+                if (!pos)
+                    value = strdup (EVAL_STR_FALSE);
+            }
+        }
+        free (condition);
+        return (value) ? value : strdup ("");
+    }
+
+    /* 11. option: if found, return this value */
     if (strncmp (text, "sec.data.", 9) == 0)
     {
         ptr_value = hashtable_get (secure_hashtable_data, text + 9);
@@ -443,7 +575,7 @@ eval_replace_vars_cb (void *data, const char *text)
         }
     }
 
-    /* 11. local variable in buffer */
+    /* 12. local variable in buffer */
     ptr_buffer = hashtable_get (pointers, "buffer");
     if (ptr_buffer)
     {
@@ -452,7 +584,7 @@ eval_replace_vars_cb (void *data, const char *text)
             return strdup (ptr_value);
     }
 
-    /* 12. hdata */
+    /* 13. hdata */
     value = NULL;
     hdata_name = NULL;
     list_name = NULL;
@@ -536,6 +668,7 @@ eval_replace_vars (const char *expr, struct t_hashtable *pointers,
                    struct t_eval_regex *eval_regex)
 {
     const void *ptr[6];
+    const char *no_replace_prefix_list[] = { "if:", NULL };
 
     ptr[0] = pointers;
     ptr[1] = extra_vars;
@@ -545,6 +678,7 @@ eval_replace_vars (const char *expr, struct t_hashtable *pointers,
     ptr[5] = eval_regex;
 
     return string_replace_with_callback (expr, prefix, suffix,
+                                         no_replace_prefix_list,
                                          &eval_replace_vars_cb, ptr, NULL);
 }
 
@@ -651,51 +785,6 @@ end:
 }
 
 /*
- * Searches a string in another at same level (skip sub-expressions between
- * parentheses).
- *
- * For example: eval_strstr_level ("(x || y) || z", "||")
- * will return a pointer on  "|| z" (because the first "||" is
- * in a sub-expression, which is skipped).
- *
- * Returns pointer to string found, or NULL if not found.
- */
-
-const char *
-eval_strstr_level (const char *string, const char *search)
-{
-    const char *ptr_string;
-    int level, length;
-
-    if (!string || !search)
-        return NULL;
-
-    length = strlen (search);
-
-    ptr_string = string;
-    level = 0;
-    while (ptr_string[0])
-    {
-        if (ptr_string[0] == '(')
-        {
-            level++;
-        }
-        else if (ptr_string[0] == ')')
-        {
-            if (level > 0)
-                level--;
-        }
-
-        if ((level == 0) && (strncmp (ptr_string, search, length) == 0))
-            return ptr_string;
-
-        ptr_string++;
-    }
-
-    return NULL;
-}
-
-/*
  * Evaluates a condition (this function must not be called directly).
  *
  * For return value, see function eval_expression().
@@ -751,7 +840,7 @@ eval_expression_condition (const char *expr,
      */
     for (logic = 0; logic < EVAL_NUM_LOGICAL_OPS; logic++)
     {
-        pos = eval_strstr_level (expr2, logical_ops[logic]);
+        pos = eval_strstr_level (expr2, logical_ops[logic], "(", ")", 0);
         if (pos > expr2)
         {
             pos_end = pos - 1;
@@ -804,7 +893,7 @@ eval_expression_condition (const char *expr,
      */
     for (comp = 0; comp < EVAL_NUM_COMPARISONS; comp++)
     {
-        pos = eval_strstr_level (expr2, comparisons[comp]);
+        pos = eval_strstr_level (expr2, comparisons[comp], "(", ")", 0);
         if (pos > expr2)
         {
             pos_end = pos - 1;
diff --git a/src/core/wee-string.c b/src/core/wee-string.c
index 2c4711b09..cd21a94c7 100644
--- a/src/core/wee-string.c
+++ b/src/core/wee-string.c
@@ -2910,6 +2910,12 @@ string_input_for_buffer (const char *string)
  *
  * Nested variables are supported, for example: "${var1:${var2}}".
  *
+ * Argument "list_prefix_no_replace" is a list to prevent replacements in
+ * string if beginning with one of the prefixes. For example if the list is
+ * { "if:", NULL } and string is: "${if:cond?true:false}${test${abc}}"
+ * then the "if:cond?true:false" is NOT replaced (via a recursive call) but
+ * "test${abc}" will be replaced.
+ *
  * Argument "errors" (if not NULL) is set with number of keys not found by
  * callback.
  *
@@ -2920,12 +2926,13 @@ char *
 string_replace_with_callback (const char *string,
                               const char *prefix,
                               const char *suffix,
+                              const char **list_prefix_no_replace,
                               char *(*callback)(void *data, const char *text),
                               void *callback_data,
                               int *errors)
 {
     int length_prefix, length_suffix, length, length_value, index_string;
-    int index_result, sub_count, sub_level, sub_errors;
+    int index_result, sub_count, sub_level, sub_errors, replace, i;
     char *result, *result2, *key, *key2, *value;
     const char *pos_end_name;
 
@@ -2991,15 +2998,36 @@ string_replace_with_callback (const char *string,
                 {
                     if (sub_count > 0)
                     {
-                        sub_errors = 0;
-                        key2 = string_replace_with_callback (key, prefix,
-                                                             suffix, callback,
-                                                             callback_data,
-                                                             &sub_errors);
-                        if (errors)
-                            (*errors) += sub_errors;
-                        free (key);
-                        key = key2;
+                        replace = 1;
+                        if (list_prefix_no_replace)
+                        {
+                            for (i = 0; list_prefix_no_replace[i]; i++)
+                            {
+                                if (strncmp (
+                                        key, list_prefix_no_replace[i],
+                                        strlen (list_prefix_no_replace[i])) == 0)
+                                {
+                                    replace = 0;
+                                    break;
+                                }
+                            }
+                        }
+                        if (replace)
+                        {
+                            sub_errors = 0;
+                            key2 = string_replace_with_callback (
+                                key,
+                                prefix,
+                                suffix,
+                                list_prefix_no_replace,
+                                callback,
+                                callback_data,
+                                &sub_errors);
+                            if (errors)
+                                (*errors) += sub_errors;
+                            free (key);
+                            key = key2;
+                        }
                     }
                     value = (*callback) (callback_data, (key) ? key : "");
                     if (value)
diff --git a/src/core/wee-string.h b/src/core/wee-string.h
index bfed81411..c3d6b933e 100644
--- a/src/core/wee-string.h
+++ b/src/core/wee-string.h
@@ -110,6 +110,7 @@ extern const char *string_input_for_buffer (const char *string);
 extern char *string_replace_with_callback (const char *string,
                                            const char *prefix,
                                            const char *suffix,
+                                           const char **list_prefix_no_replace,
                                            char *(*callback)(void *data, const char *text),
                                            void *callback_data,
                                            int *errors);