[tracker/wip/carlosg/sparql1.1: 60/201] libtracker-data: Add more functions to transform between times

[Carlos Garnacho <carlosg src gnome org>]

commit 0c5431a410a2d45b011f87959201d2ea72f5fa72
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Mar 3 21:42:25 2019 +0100

    libtracker-data: Add more functions to transform between times
    
    We now have SparqlTimeSort, which provides an int64 suitable for sorting,
    and SparqlTimestamp that gets a unix timestamp from a time string.
    In addition, SparqlFormatTime now is able to handle both int and string
    types (just forwards it in the latter case).

 src/libtracker-data/tracker-db-interface-sqlite.c | 106 +++++++++++++++++++++-
 1 file changed, 101 insertions(+), 5 deletions(-)
---
diff --git a/src/libtracker-data/tracker-db-interface-sqlite.c 
b/src/libtracker-data/tracker-db-interface-sqlite.c
index e151d4ed3..8baddb26a 100644
--- a/src/libtracker-data/tracker-db-interface-sqlite.c
+++ b/src/libtracker-data/tracker-db-interface-sqlite.c
@@ -414,9 +414,36 @@ function_sparql_format_time (sqlite3_context *context,
                              int              argc,
                              sqlite3_value   *argv[])
 {
-       gdouble seconds;
-       gchar *str;
+       if (argc != 1) {
+               sqlite3_result_error (context, "Invalid argument count", -1);
+               return;
+       }
 
+       if (sqlite3_value_type (argv[0]) == SQLITE_NULL) {
+               sqlite3_result_null (context);
+               return;
+       } else if (sqlite3_value_numeric_type (argv[0]) == SQLITE_INTEGER) {
+               gdouble seconds;
+               gchar *str;
+
+               seconds = sqlite3_value_double (argv[0]);
+               str = tracker_date_to_string (seconds, 0);
+               sqlite3_result_text (context, str, -1, g_free);
+       } else if (sqlite3_value_type (argv[0]) == SQLITE_TEXT) {
+               const gchar *str;
+
+               str = sqlite3_value_text (argv[0]);
+               sqlite3_result_text (context, g_strdup (str), -1, g_free);
+       } else {
+               sqlite3_result_error (context, "Invalid argument type", -1);
+       }
+}
+
+static void
+function_sparql_timestamp (sqlite3_context *context,
+                           int              argc,
+                           sqlite3_value   *argv[])
+{
        if (argc != 1) {
                sqlite3_result_error (context, "Invalid argument count", -1);
                return;
@@ -425,12 +452,77 @@ function_sparql_format_time (sqlite3_context *context,
        if (sqlite3_value_type (argv[0]) == SQLITE_NULL) {
                sqlite3_result_null (context);
                return;
+       } else if (sqlite3_value_numeric_type (argv[0]) == SQLITE_INTEGER) {
+               gdouble seconds;
+
+               seconds = sqlite3_value_double (argv[0]);
+               sqlite3_result_double (context, seconds);
+       } else if (sqlite3_value_type (argv[0]) == SQLITE_TEXT) {
+               GError *error = NULL;
+               const gchar *str;
+               gdouble time;
+
+               str = sqlite3_value_text (argv[0]);
+               time = tracker_string_to_date (str, NULL, &error);
+
+               if (error) {
+                       sqlite3_result_error (context, "Failed time string conversion", -1);
+                       g_error_free (error);
+                       return;
+               }
+
+               sqlite3_result_double (context, time);
+       } else {
+               sqlite3_result_error (context, "Invalid argument type", -1);
+       }
+}
+
+static void
+function_sparql_time_sort (sqlite3_context *context,
+                           int              argc,
+                           sqlite3_value   *argv[])
+{
+       gint64 sort_key;
+
+       if (argc != 1) {
+               sqlite3_result_error (context, "Invalid argument count", -1);
+               return;
        }
 
-       seconds = sqlite3_value_double (argv[0]);
-       str = tracker_date_to_string (seconds, 0);
+       if (sqlite3_value_type (argv[0]) == SQLITE_NULL) {
+               sqlite3_result_null (context);
+               return;
+       } else if (sqlite3_value_numeric_type (argv[0]) == SQLITE_INTEGER) {
+               gint64 value;
+
+               value = sqlite3_value_int64 (argv[0]);
+               sort_key = value * G_USEC_PER_SEC;
+
+               if (sort_key < value) {
+                       sqlite3_result_error (context, "Invalid integer argument value", -1);
+                       return;
+               }
+       } else if (sqlite3_value_type (argv[0]) == SQLITE_TEXT) {
+               const gchar *value;
+               gdouble time;
+               GError *error = NULL;
+
+               value = sqlite3_value_text (argv[0]);
+               time = tracker_string_to_date (value, NULL, &error);
+
+               if (error) {
+                       sqlite3_result_error (context, "Failed time string conversion", -1);
+                       g_error_free (error);
+                       return;
+               }
+
+               sort_key = (gint64) (time * G_USEC_PER_SEC);
+       } else {
+               sqlite3_result_error (context, "Invalid argument type", -1);
+               return;
+       }
 
-       sqlite3_result_text (context, str, -1, g_free);
+       sqlite3_result_int64 (context, sort_key);
 }
 
 static void
@@ -1438,6 +1530,10 @@ initialize_functions (TrackerDBInterface *db_interface)
                /* Date/time */
                { "SparqlFormatTime", 1, SQLITE_ANY | SQLITE_DETERMINISTIC,
                  function_sparql_format_time },
+               { "SparqlTimestamp", 1, SQLITE_ANY | SQLITE_DETERMINISTIC,
+                 function_sparql_timestamp },
+               { "SparqlTimeSort", 1, SQLITE_ANY | SQLITE_DETERMINISTIC,
+                 function_sparql_time_sort },
                /* Paths and filenames */
                { "SparqlStringFromFilename", 1, SQLITE_ANY | SQLITE_DETERMINISTIC,
                  function_sparql_string_from_filename },