blogc: renderer: add `FOREACH_VALUE` variable

5 files changed, 127 insertions, 29 deletions

diff --git a/man/blogc-template.7.ronn b/man/blogc-template.7.ronn
index 5184941..1530fb3 100644
--- a/man/blogc-template.7.ronn
+++ b/man/blogc-template.7.ronn
@@ -317,16 +317,40 @@ This is how a `foreach` iterator is defined in a template:
     {% endforeach %}
 
 Where `TAGS` is the variable with space-separated list of items, and `FOREACH_ITEM`
-is the variable defined by blogc(1), that will store the item value for a given
-iteration.
+is the variable defined by blogc(1), that will store the item for a given iteration.
 
 If the value of the `TAGS` variable is "item1 item2 item3", this template is
-rendered 3 times, one for each item value.
+rendered 3 times, one for each item.
 
-The `FOREACH_ITEM` variable can be truncated, like:
+It is possible to map the items to arbitrary strings by defining other variables
+following a predefined for naming schema, like:
+
+    TAGS__ITEM1
+
+Where `TAGS` is the variable defined in the foreach iterator, and `ITEM1` is the
+current iteration item (the value of `FOREACH_ITEM` for the current iteration,
+converted to upper case and with special characters converted to `_`).
+
+This is how a `foreach` iterator using arbitrary string mapping is defined in a template:
+
+    {% foreach TAGS %}
+    <a href="/tag/{{ FOREACH_ITEM }}/">{{ FOREACH_VALUE }}</a>
+    {% endforeach %}
+
+`FOREACH_VALUE` is the variable defined by blogc(1), that will store the arbitrary string
+mapped to current iteration item. This variable can be checked using `ifdef` conditionals
+(and similar) as usual:
+
+    {% foreach TAGS %}
+    {% ifdef FOREACH_VALUE %}
+    <a href="/tag/{{ FOREACH_ITEM }}/">{{ FOREACH_VALUE }}</a>
+    {% endif %}
+    {% endforeach %}
+
+The `FOREACH_ITEM` and `FOREACH_VALUE` variables can be truncated, like:
 
     {% foreach TAGS %}
-    <a href="/tag/{{ FOREACH_ITEM }}/">{{ FOREACH_ITEM_5 }}</a>
+    <a href="/tag/{{ FOREACH_ITEM_5 }}/">{{ FOREACH_VALUE_5 }}</a>
     {% endforeach %}
 
 ## WHITESPACE CONTROL
diff --git a/src/blogc/main.c b/src/blogc/main.c
index 7024967..9bfa9cf 100644
--- a/src/blogc/main.c
+++ b/src/blogc/main.c
@@ -322,7 +322,7 @@ main(int argc, char **argv)
         if (!listing && s != NULL) {
             local = s->data;
         }
-        char *val = blogc_format_variable(print, config, local, NULL);
+        char *val = blogc_format_variable(print, config, local, NULL, NULL);
         if (val == NULL) {
             fprintf(stderr, "blogc: error: variable not found: %s\n",
                 print);
diff --git a/src/blogc/renderer.c b/src/blogc/renderer.c
index 785c77b..a91d105 100644
--- a/src/blogc/renderer.c
+++ b/src/blogc/renderer.c
@@ -54,22 +54,57 @@ blogc_format_date(const char *date, bc_trie_t *global, bc_trie_t *local)
 }
 
 
+static char*
+foreach_value_variable(const char *name, const char *item)
+{
+    if (name == NULL || item == NULL)
+        return NULL;
+
+    char *rv = bc_strdup_printf("%s__%s", name, item);
+    int diff = 'a' - 'A';  // just to avoid magic numbers
+    for (size_t i = 0; rv[i] != '\0'; i++) {
+        if ((rv[i] >= '0' && rv[i] <= '9') ||
+            (rv[i] >= 'A' && rv[i] <= 'Z')) {
+            continue;
+        }
+        if (rv[i] >= 'a' && rv[i] <= 'z') {
+            rv[i] -= diff;
+            continue;
+        }
+        rv[i] = '_';
+    }
+
+    return rv;
+}
+
+
 char*
 blogc_format_variable(const char *name, bc_trie_t *global, bc_trie_t *local,
-    bc_slist_t *foreach_var)
+    const char *foreach_name, bc_slist_t *foreach_var)
 {
     // if used asked for a variable that exists, just return it right away
     const char *value = blogc_get_variable(name, global, local);
     if (value != NULL)
         return bc_strdup(value);
 
-    // do the same for special variable 'FOREACH_ITEM'
+    // do the same for special foreach variables
     if (0 == strcmp(name, "FOREACH_ITEM")) {
         if (foreach_var != NULL && foreach_var->data != NULL) {
             return bc_strdup(foreach_var->data);
         }
         return NULL;
     }
+    if (0 == strcmp(name, "FOREACH_VALUE")) {
+        if (foreach_name != NULL && foreach_var != NULL && foreach_var->data != NULL) {
+            char *value_var = foreach_value_variable(foreach_name, foreach_var->data);
+            if (value_var != NULL) {
+                value = blogc_get_variable(value_var, global, local);
+                free(value_var);
+                return bc_strdup(value);
+            }
+        }
+        return NULL;
+    }
 
     char *var = bc_strdup(name);
 
@@ -105,6 +140,14 @@ blogc_format_variable(const char *name, bc_trie_t *global, bc_trie_t *local,
         (foreach_var != NULL && foreach_var->data != NULL)) {
         value = foreach_var->data;
     }
+    else if ((0 == strcmp(var, "FOREACH_VALUE")) &&
+        (foreach_name != NULL && foreach_var != NULL && foreach_var->data != NULL)) {
+        char *value_var = foreach_value_variable(foreach_name, foreach_var->data);
+        if (value_var != NULL) {
+            value = blogc_get_variable(value_var, global, local);
+            free(value_var);
+        }
+    }
     else {
         blogc_funcvars_eval(global, var);
         value = blogc_get_variable(var, global, local);
@@ -183,6 +226,7 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
 
     size_t if_count = 0;
 
+    char *foreach_name = NULL;
     bc_slist_t *foreach_var = NULL;
     bc_slist_t *foreach_var_start = NULL;
     bc_slist_t *foreach_start = NULL;
@@ -289,7 +333,7 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
             case BLOGC_TEMPLATE_NODE_VARIABLE:
                 if (node->data[0] != NULL) {
                     config_value = blogc_format_variable(node->data[0],
-                        config, inside_block ? tmp_source : NULL, foreach_var);
+                        config, inside_block ? tmp_source : NULL, foreach_name, foreach_var);
                     if (config_value != NULL) {
                         bc_string_append(str, config_value);
                         free(config_value);
@@ -321,7 +365,7 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
                 defined = NULL;
                 if (node->data[0] != NULL)
                     defined = blogc_format_variable(node->data[0], config,
-                        inside_block ? tmp_source : NULL, foreach_var);
+                        inside_block ? tmp_source : NULL, foreach_name, foreach_var);
                 evaluate = false;
                 if (node->op != 0) {
                     // Strings that start with a '"' are actually strings, the
@@ -339,7 +383,7 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
                         else {
                             defined2 = blogc_format_variable(node->data[1],
                                 config, inside_block ? tmp_source : NULL,
-                                foreach_var);
+                                foreach_name, foreach_var);
                         }
                     }
 
@@ -452,6 +496,7 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
                             config, inside_block ? tmp_source : NULL);
 
                     if (foreach_var_start != NULL) {
+                        foreach_name = bc_strdup(node->data[0]);
                         foreach_var = foreach_var_start;
                         foreach_start = tmp;
                     }
@@ -469,6 +514,7 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
 
                 if (foreach_var == NULL) {
                     foreach_start = tmp;
+                    foreach_name = bc_strdup(node->data[0]);
                     foreach_var = foreach_var_start;
                 }
                 break;
@@ -484,6 +530,8 @@ blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
                 foreach_start = NULL;
                 bc_slist_free_full(foreach_var_start, free);
                 foreach_var_start = NULL;
+                free(foreach_name);
+                foreach_name = NULL;
                 break;
         }
         tmp = tmp->next;
diff --git a/src/blogc/renderer.h b/src/blogc/renderer.h
index 77f20f5..77c660a 100644
--- a/src/blogc/renderer.h
+++ b/src/blogc/renderer.h
@@ -15,7 +15,7 @@
 const char* blogc_get_variable(const char *name, bc_trie_t *global, bc_trie_t *local);
 char* blogc_format_date(const char *date, bc_trie_t *global, bc_trie_t *local);
 char* blogc_format_variable(const char *name, bc_trie_t *global, bc_trie_t *local,
-    bc_slist_t *foreach_var);
+    const char *foreach_name, bc_slist_t *foreach_var);
 bc_slist_t* blogc_split_list_variable(const char *name, bc_trie_t *global,
     bc_trie_t *local);
 char* blogc_render(bc_slist_t *tmpl, bc_slist_t *sources, bc_slist_t *listing_entries,
diff --git a/tests/blogc/check_renderer.c b/tests/blogc/check_renderer.c
index a5d6729..08aed84 100644
--- a/tests/blogc/check_renderer.c
+++ b/tests/blogc/check_renderer.c
@@ -1253,23 +1253,23 @@ test_format_variable(void **state)
     bc_trie_insert(l, "NAME", bc_strdup("chunda"));
     bc_trie_insert(l, "TITLE", bc_strdup("chunda2"));
     bc_trie_insert(l, "SIZE", bc_strdup("1234567890987654321"));
-    char *tmp = blogc_format_variable("NAME", g, l, NULL);
+    char *tmp = blogc_format_variable("NAME", g, l, NULL, NULL);
     assert_string_equal(tmp, "chunda");
     free(tmp);
-    tmp = blogc_format_variable("TITLE", g, l, NULL);
+    tmp = blogc_format_variable("TITLE", g, l, NULL, NULL);
     assert_string_equal(tmp, "chunda2");
     free(tmp);
-    tmp = blogc_format_variable("TITLE_2", g, l, NULL);
+    tmp = blogc_format_variable("TITLE_2", g, l, NULL, NULL);
     assert_string_equal(tmp, "ch");
     free(tmp);
-    tmp = blogc_format_variable("SIZE_12", g, l, NULL);
+    tmp = blogc_format_variable("SIZE_12", g, l, NULL, NULL);
     assert_string_equal(tmp, "123456789098");
     free(tmp);
-    tmp = blogc_format_variable("SIZE_200", g, l, NULL);
+    tmp = blogc_format_variable("SIZE_200", g, l, NULL, NULL);
     assert_string_equal(tmp, "1234567890987654321");
     free(tmp);
-    assert_null(blogc_format_variable("SIZE_", g, l, NULL));
-    assert_null(blogc_format_variable("BOLA", g, l, NULL));
+    assert_null(blogc_format_variable("SIZE_", g, l, NULL, NULL));
+    assert_null(blogc_format_variable("BOLA", g, l, NULL, NULL));
     bc_trie_free(g);
     bc_trie_free(l);
 }
@@ -1283,13 +1283,13 @@ test_format_variable_with_date(void **state)
     bc_trie_insert(g, "DATE_FORMAT", bc_strdup("%R"));
     bc_trie_t *l = bc_trie_new(free);
     bc_trie_insert(l, "DATE", bc_strdup("2011-12-13 14:15:16"));
-    char *tmp = blogc_format_variable("DATE_FORMATTED", g, l, NULL);
+    char *tmp = blogc_format_variable("DATE_FORMATTED", g, l, NULL, NULL);
     assert_string_equal(tmp, "14:15");
     free(tmp);
-    tmp = blogc_format_variable("DATE_FORMATTED_3", g, l, NULL);
+    tmp = blogc_format_variable("DATE_FORMATTED_3", g, l, NULL, NULL);
     assert_string_equal(tmp, "14:");
     free(tmp);
-    tmp = blogc_format_variable("DATE_FORMATTED_10", g, l, NULL);
+    tmp = blogc_format_variable("DATE_FORMATTED_10", g, l, NULL, NULL);
     assert_string_equal(tmp, "14:15");
     free(tmp);
     bc_trie_free(g);
@@ -1304,15 +1304,13 @@ test_format_variable_foreach(void **state)
     l = bc_slist_append(l, bc_strdup("asd"));
     l = bc_slist_append(l, bc_strdup("qwe"));
     l = bc_slist_append(l, bc_strdup("zxcvbn"));
-    char *tmp = blogc_format_variable("FOREACH_ITEM", NULL, NULL, l->next);
+    char *tmp = blogc_format_variable("FOREACH_ITEM", NULL, NULL, NULL, l->next);
     assert_string_equal(tmp, "qwe");
     free(tmp);
-    tmp = blogc_format_variable("FOREACH_ITEM_4", NULL, NULL,
-        l->next->next);
+    tmp = blogc_format_variable("FOREACH_ITEM_4", NULL, NULL, NULL, l->next->next);
     assert_string_equal(tmp, "zxcv");
     free(tmp);
-    tmp = blogc_format_variable("FOREACH_ITEM_10", NULL, NULL,
-        l->next->next);
+    tmp = blogc_format_variable("FOREACH_ITEM_10", NULL, NULL, NULL, l->next->next);
     assert_string_equal(tmp, "zxcvbn");
     free(tmp);
     bc_slist_free_full(l, free);
@@ -1320,10 +1318,37 @@ test_format_variable_foreach(void **state)
 
 
 static void
+test_format_variable_foreach_value(void **state)
+{
+    bc_trie_t *gl = bc_trie_new(free);
+    bc_trie_insert(gl, "FOO_BAR__QWE", bc_strdup("bnm"));
+    bc_trie_t *loc = bc_trie_new(free);
+    bc_trie_insert(loc, "BAR__ZXCVBN", bc_strdup("dfg"));
+    bc_trie_insert(loc, "HUE__ZXCVBN", bc_strdup("xcv"));
+    bc_slist_t *l = NULL;
+    l = bc_slist_append(l, bc_strdup("asd"));
+    l = bc_slist_append(l, bc_strdup("qwe"));
+    l = bc_slist_append(l, bc_strdup("zxcvbn"));
+    char *tmp = blogc_format_variable("FOREACH_VALUE", gl, loc, "foo-bar", l->next);
+    assert_string_equal(tmp, "bnm");
+    free(tmp);
+    tmp = blogc_format_variable("FOREACH_VALUE_2", gl, loc, "bar", l->next->next);
+    assert_string_equal(tmp, "df");
+    free(tmp);
+    tmp = blogc_format_variable("FOREACH_VALUE_4", gl, loc, "hue", l->next->next);
+    assert_string_equal(tmp, "xcv");
+    free(tmp);
+    bc_trie_free(gl);
+    bc_trie_free(loc);
+    bc_slist_free_full(l, free);
+}
+
+
+static void
 test_format_variable_foreach_empty(void **state)
 {
-    assert_null(blogc_format_variable("FOREACH_ITEM", NULL, NULL, NULL));
-    assert_null(blogc_format_variable("FOREACH_ITEM_4", NULL, NULL, NULL));
+    assert_null(blogc_format_variable("FOREACH_ITEM", NULL, NULL, NULL, NULL));
+    assert_null(blogc_format_variable("FOREACH_ITEM_4", NULL, NULL, NULL, NULL));
 }
 
 
@@ -1401,6 +1426,7 @@ main(void)
         cmocka_unit_test(test_format_variable),
         cmocka_unit_test(test_format_variable_with_date),
         cmocka_unit_test(test_format_variable_foreach),
+        cmocka_unit_test(test_format_variable_foreach_value),
         cmocka_unit_test(test_format_variable_foreach_empty),
         cmocka_unit_test(test_split_list_variable),
         cmocka_unit_test(test_split_list_variable_not_found),