blogc: added FILTER_SORT, to sort posts by DATE

3 files changed, 278 insertions, 49 deletions

diff --git a/man/blogc-pagination.7.ronn b/man/blogc-pagination.7.ronn
index 4b3b4b6..cca8aba 100644
--- a/man/blogc-pagination.7.ronn
+++ b/man/blogc-pagination.7.ronn
@@ -30,9 +30,15 @@ files passed as arguments to it:
     provided tag, instead of filtering the whole file set.
 
   * `FILTER_REVERSE`:
-    Any string, if defined, blogc(1) will list files in reverse order. This
-    is always the first filter applied to the files. All the other filters will
-    get the files already in the reverse order, and won't care about this.
+    Boolean (1/y/yes/true/on), if set, blogc(1) will list files in reverse order.
+    This is always the first filter applied to the files. All the previous filters
+    will get the files already in the reverse order, and won't care about this.
+
+  * `FILTER_SORT`:
+    Boolean (1/y/yes/true/on), if set, blogc(1) will sort files using the `DATE`
+    variable provided in the files, instead of respecting the order of the
+    source files provided to blogc(1). All the previous filters will get the
+    files already sorted, and won't care about this.
 
 ## TEMPLATE VARIABLES
 
diff --git a/src/blogc/loader.c b/src/blogc/loader.c
index ea427de..029acbf 100644
--- a/src/blogc/loader.c
+++ b/src/blogc/loader.c
@@ -12,12 +12,14 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include "datetime-parser.h"
 #include "source-parser.h"
 #include "template-parser.h"
 #include "loader.h"
 #include "../common/error.h"
 #include "../common/file.h"
 #include "../common/utils.h"
+#include "../common/sort.h"
 
 
 char*
@@ -97,26 +99,104 @@ blogc_source_parse_from_file(const char *f, bc_error_t **err)
 }
 
 
+static int
+sort_source(const void *a, const void *b)
+{
+    const char *ca = bc_trie_lookup((bc_trie_t*) a, "c");
+    const char *cb = bc_trie_lookup((bc_trie_t*) b, "c");
+
+    if (ca == NULL || cb == NULL) {
+        return 0;  // wat
+    }
+
+    return strcmp(cb, ca);
+}
+
+
+static int
+sort_source_reverse(const void *a, const void *b)
+{
+    return sort_source(b, a);
+}
+
+
 bc_slist_t*
 blogc_source_parse_from_files(bc_trie_t *conf, bc_slist_t *l, bc_error_t **err)
 {
     if (err == NULL || *err != NULL)
         return NULL;
 
-    bool reverse = bc_trie_lookup(conf, "FILTER_REVERSE");
+    bool sort = bc_str_to_bool(bc_trie_lookup(conf, "FILTER_SORT"));
+
     bc_slist_t* sources = NULL;
+    bc_error_t *tmp_err = NULL;
+    size_t with_date = 0;
     for (bc_slist_t *tmp = l; tmp != NULL; tmp = tmp->next) {
-        if (reverse) {
-            sources = bc_slist_prepend(sources, tmp->data);
+        char *f = tmp->data;
+        bc_trie_t *s = blogc_source_parse_from_file(f, &tmp_err);
+        if (s == NULL) {
+            *err = bc_error_new_printf(BLOGC_ERROR_LOADER,
+                "An error occurred while parsing source file: %s\n\n%s",
+                f, tmp_err->msg);
+            bc_error_free(tmp_err);
+            bc_slist_free_full(sources, (bc_free_func_t) bc_trie_free);
+            return NULL;
         }
-        else {
-            sources = bc_slist_append(sources, tmp->data);
+
+        const char *date = bc_trie_lookup(s, "DATE");
+        if (date != NULL) {
+            with_date++;
+        }
+
+        if (sort) {
+            if (date == NULL) {
+                *err = bc_error_new_printf(BLOGC_ERROR_LOADER,
+                    "'FILTER_SORT' requires that 'DATE' variable is set for "
+                    "every source file: %s", f);
+                bc_trie_free(s);
+                bc_slist_free_full(sources, (bc_free_func_t) bc_trie_free);
+                return NULL;
+            }
+
+            char *timestamp = blogc_convert_datetime(date, "%s", &tmp_err);
+            if (timestamp == NULL) {
+                *err = bc_error_new_printf(BLOGC_ERROR_LOADER,
+                    "An error occurred while parsing 'DATE' variable: %s"
+                    "\n\n%s", f, tmp_err->msg);
+                bc_error_free(tmp_err);
+                bc_trie_free(s);
+                bc_slist_free_full(sources, (bc_free_func_t) bc_trie_free);
+                return NULL;
+            }
+
+            bc_trie_insert(s, "c", timestamp);
         }
+
+        sources = bc_slist_append(sources, s);
     }
 
-    bc_error_t *tmp_err = NULL;
-    bc_slist_t *rv = NULL;
-    size_t with_date = 0;
+    if (with_date > 0 && with_date < bc_slist_length(l)) {
+        *err = bc_error_new_printf(BLOGC_ERROR_LOADER,
+            "'DATE' variable provided for at least one source file, but not "
+            "for all source files. It must be provided for all files.");
+        bc_slist_free_full(sources, (bc_free_func_t) bc_trie_free);
+        return NULL;
+    }
+
+    bool reverse = bc_str_to_bool(bc_trie_lookup(conf, "FILTER_REVERSE"));
+
+    if (sort) {
+        sources = bc_slist_sort(sources, reverse ? sort_source_reverse : sort_source);
+    }
+    else if (reverse) {
+        bc_slist_t *tmp_sources = NULL;
+        for (bc_slist_t *tmp = sources; tmp != NULL; tmp = tmp->next) {
+            tmp_sources = bc_slist_prepend(tmp_sources, tmp->data);
+        }
+        bc_slist_t *tmp = sources;
+        sources = tmp_sources;
+        bc_slist_free(tmp);
+    }
 
     const char *filter_tag = bc_trie_lookup(conf, "FILTER_TAG");
     const char *filter_page = bc_trie_lookup(conf, "FILTER_PAGE");
@@ -146,19 +226,9 @@ blogc_source_parse_from_files(bc_trie_t *conf, bc_slist_t *l, bc_error_t **err)
     size_t end = start + per_page;
     size_t counter = 0;
 
+    bc_slist_t *rv = NULL;
     for (bc_slist_t *tmp = sources; tmp != NULL; tmp = tmp->next) {
-        char *f = tmp->data;
-        bc_trie_t *s = blogc_source_parse_from_file(f, &tmp_err);
-        if (s == NULL) {
-            *err = bc_error_new_printf(BLOGC_ERROR_LOADER,
-                "An error occurred while parsing source file: %s\n\n%s",
-                f, tmp_err->msg);
-            bc_error_free(tmp_err);
-            tmp_err = NULL;
-            bc_slist_free_full(rv, (bc_free_func_t) bc_trie_free);
-            rv = NULL;
-            break;
-        }
+        bc_trie_t *s = tmp->data;
         if (filter_tag != NULL) {
             const char *tags_str = bc_trie_lookup(s, "TAGS");
             // if user wants to filter by tag and no tag is provided, skip it
@@ -188,21 +258,11 @@ blogc_source_parse_from_files(bc_trie_t *conf, bc_slist_t *l, bc_error_t **err)
             }
             counter++;
         }
-        if (bc_trie_lookup(s, "DATE") != NULL)
-            with_date++;
         rv = bc_slist_append(rv, s);
     }
 
     bc_slist_free(sources);
 
-    if (with_date > 0 && with_date < bc_slist_length(rv)) {
-        *err = bc_error_new_printf(BLOGC_ERROR_LOADER,
-            "'DATE' variable provided for at least one source file, but not "
-            "for all source files. It must be provided for all files.\n");
-        bc_slist_free_full(rv, (bc_free_func_t) bc_trie_free);
-        rv = NULL;
-    }
-
     bool first = true;
     for (bc_slist_t *tmp = rv; tmp != NULL; tmp = tmp->next) {
         bc_trie_t *s = tmp->data;
diff --git a/tests/blogc/check_loader.c b/tests/blogc/check_loader.c
index f7f2024..d65f418 100644
--- a/tests/blogc/check_loader.c
+++ b/tests/blogc/check_loader.c
@@ -169,21 +169,52 @@ test_source_parse_from_files(void **state)
 
 
 static void
-test_source_parse_from_files_filter_reverse(void **state)
+test_source_parse_from_files_filter_sort(void **state)
 {
-    will_return(__wrap_bc_file_get_contents, "bola3.txt");
+    will_return(__wrap_bc_file_get_contents, "bola1.txt");
     will_return(__wrap_bc_file_get_contents, bc_strdup(
-        "ASD: 789\n"
-        "DATE: 2003-02-03 04:05:06\n"
+        "ASD: 123\n"
+        "DATE: 2001-02-02 04:05:06\n"
         "--------\n"
         "bola"));
     will_return(__wrap_bc_file_get_contents, "bola2.txt");
     will_return(__wrap_bc_file_get_contents, bc_strdup(
         "ASD: 456\n"
-        "DATE: 2002-02-03 04:05:06\n"
-        "TAGS: bola, chunda\n"
+        "DATE: 2001-02-01 04:05:06\n"
         "--------\n"
         "bola"));
+    will_return(__wrap_bc_file_get_contents, "bola3.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 789\n"
+        "DATE: 2001-02-03 04:05:06\n"
+        "--------\n"
+        "bola"));
+    bc_error_t *err = NULL;
+    bc_slist_t *s = NULL;
+    s = bc_slist_append(s, bc_strdup("bola1.txt"));
+    s = bc_slist_append(s, bc_strdup("bola2.txt"));
+    s = bc_slist_append(s, bc_strdup("bola3.txt"));
+    bc_trie_t *c = bc_trie_new(free);
+    bc_trie_insert(c, "FILTER_SORT", bc_strdup("1"));
+    bc_slist_t *t = blogc_source_parse_from_files(c, s, &err);
+    assert_null(err);
+    assert_non_null(t);
+    assert_int_equal(bc_slist_length(t), 3);  // it is enough, no need to look at the items
+    assert_int_equal(bc_trie_size(c), 5);
+    assert_string_equal(bc_trie_lookup(c, "FILTER_SORT"), "1");
+    assert_string_equal(bc_trie_lookup(c, "FILENAME_FIRST"), "bola3");
+    assert_string_equal(bc_trie_lookup(c, "FILENAME_LAST"), "bola2");
+    assert_string_equal(bc_trie_lookup(c, "DATE_FIRST"), "2001-02-03 04:05:06");
+    assert_string_equal(bc_trie_lookup(c, "DATE_LAST"), "2001-02-01 04:05:06");
+    bc_trie_free(c);
+    bc_slist_free_full(s, free);
+    bc_slist_free_full(t, (bc_free_func_t) bc_trie_free);
+}
+
+
+static void
+test_source_parse_from_files_filter_reverse(void **state)
+{
     will_return(__wrap_bc_file_get_contents, "bola1.txt");
     will_return(__wrap_bc_file_get_contents, bc_strdup(
         "ASD: 123\n"
@@ -191,13 +222,26 @@ test_source_parse_from_files_filter_reverse(void **state)
         "TAGS: chunda\n"
         "--------\n"
         "bola"));
+    will_return(__wrap_bc_file_get_contents, "bola2.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 456\n"
+        "DATE: 2002-02-03 04:05:06\n"
+        "TAGS: bola, chunda\n"
+        "--------\n"
+        "bola"));
+    will_return(__wrap_bc_file_get_contents, "bola3.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 789\n"
+        "DATE: 2003-02-03 04:05:06\n"
+        "--------\n"
+        "bola"));
     bc_error_t *err = NULL;
     bc_slist_t *s = NULL;
     s = bc_slist_append(s, bc_strdup("bola1.txt"));
     s = bc_slist_append(s, bc_strdup("bola2.txt"));
     s = bc_slist_append(s, bc_strdup("bola3.txt"));
     bc_trie_t *c = bc_trie_new(free);
-    bc_trie_insert(c, "FILTER_REVERSE", bc_strdup(""));
+    bc_trie_insert(c, "FILTER_REVERSE", bc_strdup("1"));
     bc_slist_t *t = blogc_source_parse_from_files(c, s, &err);
     assert_null(err);
     assert_non_null(t);
@@ -207,7 +251,53 @@ test_source_parse_from_files_filter_reverse(void **state)
     assert_string_equal(bc_trie_lookup(c, "FILENAME_LAST"), "bola1");
     assert_string_equal(bc_trie_lookup(c, "DATE_FIRST"), "2003-02-03 04:05:06");
     assert_string_equal(bc_trie_lookup(c, "DATE_LAST"), "2001-02-03 04:05:06");
-    assert_string_equal(bc_trie_lookup(c, "FILTER_REVERSE"), "");
+    assert_string_equal(bc_trie_lookup(c, "FILTER_REVERSE"), "1");
+    bc_trie_free(c);
+    bc_slist_free_full(s, free);
+    bc_slist_free_full(t, (bc_free_func_t) bc_trie_free);
+}
+
+
+static void
+test_source_parse_from_files_filter_sort_reverse(void **state)
+{
+    will_return(__wrap_bc_file_get_contents, "bola1.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 123\n"
+        "DATE: 2001-02-02 04:05:06\n"
+        "--------\n"
+        "bola"));
+    will_return(__wrap_bc_file_get_contents, "bola2.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 456\n"
+        "DATE: 2001-02-01 04:05:06\n"
+        "--------\n"
+        "bola"));
+    will_return(__wrap_bc_file_get_contents, "bola3.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 789\n"
+        "DATE: 2001-02-03 04:05:06\n"
+        "--------\n"
+        "bola"));
+    bc_error_t *err = NULL;
+    bc_slist_t *s = NULL;
+    s = bc_slist_append(s, bc_strdup("bola1.txt"));
+    s = bc_slist_append(s, bc_strdup("bola2.txt"));
+    s = bc_slist_append(s, bc_strdup("bola3.txt"));
+    bc_trie_t *c = bc_trie_new(free);
+    bc_trie_insert(c, "FILTER_SORT", bc_strdup("1"));
+    bc_trie_insert(c, "FILTER_REVERSE", bc_strdup("1"));
+    bc_slist_t *t = blogc_source_parse_from_files(c, s, &err);
+    assert_null(err);
+    assert_non_null(t);
+    assert_int_equal(bc_slist_length(t), 3);  // it is enough, no need to look at the items
+    assert_int_equal(bc_trie_size(c), 6);
+    assert_string_equal(bc_trie_lookup(c, "FILTER_SORT"), "1");
+    assert_string_equal(bc_trie_lookup(c, "FILTER_REVERSE"), "1");
+    assert_string_equal(bc_trie_lookup(c, "FILENAME_FIRST"), "bola2");
+    assert_string_equal(bc_trie_lookup(c, "FILENAME_LAST"), "bola3");
+    assert_string_equal(bc_trie_lookup(c, "DATE_FIRST"), "2001-02-01 04:05:06");
+    assert_string_equal(bc_trie_lookup(c, "DATE_LAST"), "2001-02-03 04:05:06");
     bc_trie_free(c);
     bc_slist_free_full(s, free);
     bc_slist_free_full(t, (bc_free_func_t) bc_trie_free);
@@ -496,7 +586,7 @@ test_source_parse_from_files_filter_by_page3(void **state)
 
 
 static void
-test_source_parse_from_files_filter_by_page_and_tag(void **state)
+test_source_parse_from_files_filter_sort_and_by_page_and_tag(void **state)
 {
     will_return(__wrap_bc_file_get_contents, "bola1.txt");
     will_return(__wrap_bc_file_get_contents, bc_strdup(
@@ -555,6 +645,7 @@ test_source_parse_from_files_filter_by_page_and_tag(void **state)
     s = bc_slist_append(s, bc_strdup("bola6.txt"));
     s = bc_slist_append(s, bc_strdup("bola7.txt"));
     bc_trie_t *c = bc_trie_new(free);
+    bc_trie_insert(c, "FILTER_SORT", bc_strdup("1"));
     bc_trie_insert(c, "FILTER_TAG", bc_strdup("chunda"));
     bc_trie_insert(c, "FILTER_PAGE", bc_strdup("2"));
     bc_trie_insert(c, "FILTER_PER_PAGE", bc_strdup("2"));
@@ -562,11 +653,12 @@ test_source_parse_from_files_filter_by_page_and_tag(void **state)
     assert_null(err);
     assert_non_null(t);
     assert_int_equal(bc_slist_length(t), 2);  // it is enough, no need to look at the items
-    assert_int_equal(bc_trie_size(c), 11);
-    assert_string_equal(bc_trie_lookup(c, "FILENAME_FIRST"), "bola5");
-    assert_string_equal(bc_trie_lookup(c, "FILENAME_LAST"), "bola7");
-    assert_string_equal(bc_trie_lookup(c, "DATE_FIRST"), "2005-02-03 04:05:06");
-    assert_string_equal(bc_trie_lookup(c, "DATE_LAST"), "2007-02-03 04:05:06");
+    assert_int_equal(bc_trie_size(c), 12);
+    assert_string_equal(bc_trie_lookup(c, "FILENAME_FIRST"), "bola3");
+    assert_string_equal(bc_trie_lookup(c, "FILENAME_LAST"), "bola2");
+    assert_string_equal(bc_trie_lookup(c, "DATE_FIRST"), "2003-02-03 04:05:06");
+    assert_string_equal(bc_trie_lookup(c, "DATE_LAST"), "2002-02-03 04:05:06");
+    assert_string_equal(bc_trie_lookup(c, "FILTER_SORT"), "1");
     assert_string_equal(bc_trie_lookup(c, "FILTER_TAG"), "chunda");
     assert_string_equal(bc_trie_lookup(c, "FILTER_PAGE"), "2");
     assert_string_equal(bc_trie_lookup(c, "FILTER_PER_PAGE"), "2");
@@ -755,7 +847,7 @@ test_source_parse_from_files_without_all_dates(void **state)
     assert_int_equal(err->type, BLOGC_ERROR_LOADER);
     assert_string_equal(err->msg,
         "'DATE' variable provided for at least one source file, but not for "
-        "all source files. It must be provided for all files.\n");
+        "all source files. It must be provided for all files.");
     bc_error_free(err);
     assert_int_equal(bc_trie_size(c), 0);
     bc_trie_free(c);
@@ -764,6 +856,73 @@ test_source_parse_from_files_without_all_dates(void **state)
 
 
 static void
+test_source_parse_from_files_filter_sort_without_all_dates(void **state)
+{
+    will_return(__wrap_bc_file_get_contents, "bola1.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 123\n"
+        "DATE: 2002-02-03 04:05:06\n"
+        "--------\n"
+        "bola"));
+    will_return(__wrap_bc_file_get_contents, "bola2.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 456\n"
+        "--------\n"
+        "bola"));
+    bc_error_t *err = NULL;
+    bc_slist_t *s = NULL;
+    s = bc_slist_append(s, bc_strdup("bola1.txt"));
+    s = bc_slist_append(s, bc_strdup("bola2.txt"));
+    s = bc_slist_append(s, bc_strdup("bola3.txt"));
+    bc_trie_t *c = bc_trie_new(free);
+    bc_trie_insert(c, "FILTER_SORT", bc_strdup("1"));
+    bc_slist_t *t = blogc_source_parse_from_files(c, s, &err);
+    assert_null(t);
+    assert_non_null(err);
+    assert_int_equal(err->type, BLOGC_ERROR_LOADER);
+    assert_string_equal(err->msg,
+        "'FILTER_SORT' requires that 'DATE' variable is set for every source "
+        "file: bola2.txt");
+    bc_error_free(err);
+    assert_int_equal(bc_trie_size(c), 1);
+    assert_string_equal(bc_trie_lookup(c, "FILTER_SORT"), "1");
+    bc_trie_free(c);
+    bc_slist_free_full(s, free);
+}
+
+
+static void
+test_source_parse_from_files_filter_sort_with_wrong_date(void **state)
+{
+    will_return(__wrap_bc_file_get_contents, "bola1.txt");
+    will_return(__wrap_bc_file_get_contents, bc_strdup(
+        "ASD: 123\n"
+        "DATE: 2002-02-03 04:05:ab\n"
+        "--------\n"
+        "bola"));
+    bc_error_t *err = NULL;
+    bc_slist_t *s = NULL;
+    s = bc_slist_append(s, bc_strdup("bola1.txt"));
+    s = bc_slist_append(s, bc_strdup("bola2.txt"));
+    s = bc_slist_append(s, bc_strdup("bola3.txt"));
+    bc_trie_t *c = bc_trie_new(free);
+    bc_trie_insert(c, "FILTER_SORT", bc_strdup("1"));
+    bc_slist_t *t = blogc_source_parse_from_files(c, s, &err);
+    assert_null(t);
+    assert_non_null(err);
+    assert_int_equal(err->type, BLOGC_ERROR_LOADER);
+    assert_string_equal(err->msg,
+        "An error occurred while parsing 'DATE' variable: bola1.txt\n\nInvalid "
+        "first digit of seconds. Found 'a', must be integer >= 0 and <= 6.");
+    bc_error_free(err);
+    assert_int_equal(bc_trie_size(c), 1);
+    assert_string_equal(bc_trie_lookup(c, "FILTER_SORT"), "1");
+    bc_trie_free(c);
+    bc_slist_free_full(s, free);
+}
+
+
+static void
 test_source_parse_from_files_null(void **state)
 {
     bc_error_t *err = NULL;
@@ -790,15 +949,19 @@ main(void)
         unit_test(test_source_parse_from_file),
         unit_test(test_source_parse_from_file_null),
         unit_test(test_source_parse_from_files),
+        unit_test(test_source_parse_from_files_filter_sort),
         unit_test(test_source_parse_from_files_filter_reverse),
+        unit_test(test_source_parse_from_files_filter_sort_reverse),
         unit_test(test_source_parse_from_files_filter_by_tag),
         unit_test(test_source_parse_from_files_filter_by_page),
         unit_test(test_source_parse_from_files_filter_by_page2),
         unit_test(test_source_parse_from_files_filter_by_page3),
-        unit_test(test_source_parse_from_files_filter_by_page_and_tag),
+        unit_test(test_source_parse_from_files_filter_sort_and_by_page_and_tag),
         unit_test(test_source_parse_from_files_filter_by_page_invalid),
         unit_test(test_source_parse_from_files_filter_by_page_invalid2),
         unit_test(test_source_parse_from_files_without_all_dates),
+        unit_test(test_source_parse_from_files_filter_sort_without_all_dates),
+        unit_test(test_source_parse_from_files_filter_sort_with_wrong_date),
         unit_test(test_source_parse_from_files_null),
     };
     return run_tests(tests);