[tracker/wip/carlosg/sparql1.1: 139/201] libtracker-data: Add SparqlDataType() sqlite function

[Carlos Garnacho <carlosg src gnome org>]

commit da17028530290df8d225661a2a5c91a1cf1b6e6c
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sat Jul 6 13:18:53 2019 +0200

    libtracker-data: Add SparqlDataType() sqlite function
    
    This function will transform a TrackerPropertyType into an expanded
    IRI.

 src/libtracker-data/tracker-db-interface-sqlite.c | 53 +++++++++++++++++++++++
 1 file changed, 53 insertions(+)
---
diff --git a/src/libtracker-data/tracker-db-interface-sqlite.c 
b/src/libtracker-data/tracker-db-interface-sqlite.c
index d68488923..25cbe740f 100644
--- a/src/libtracker-data/tracker-db-interface-sqlite.c
+++ b/src/libtracker-data/tracker-db-interface-sqlite.c
@@ -1537,6 +1537,56 @@ function_sparql_floor (sqlite3_context *context,
        sqlite3_result_double (context, floor (value));
 }
 
+static void
+function_sparql_data_type (sqlite3_context *context,
+                           int              argc,
+                           sqlite3_value   *argv[])
+{
+       TrackerPropertyType prop_type;
+       const gchar *type = NULL;
+
+       if (argc != 1) {
+               sqlite3_result_error (context, "Invalid argument count", -1);
+               return;
+       }
+
+       prop_type = sqlite3_value_int (argv[0]);
+
+       switch (prop_type) {
+       case TRACKER_PROPERTY_TYPE_UNKNOWN:
+               break;
+       case TRACKER_PROPERTY_TYPE_STRING:
+               type = "http://www.w3.org/2001/XMLSchema#string";;
+               break;
+       case TRACKER_PROPERTY_TYPE_BOOLEAN:
+               type = "http://www.w3.org/2001/XMLSchema#boolean";;
+               break;
+       case TRACKER_PROPERTY_TYPE_INTEGER:
+               type = "http://www.w3.org/2001/XMLSchema#integer";;
+               break;
+       case TRACKER_PROPERTY_TYPE_DOUBLE:
+               type = "http://www.w3.org/2001/XMLSchema#double";;
+               break;
+       case TRACKER_PROPERTY_TYPE_DATE:
+               type = "http://www.w3.org/2001/XMLSchema#date";;
+               break;
+       case TRACKER_PROPERTY_TYPE_DATETIME:
+               type = "http://www.w3.org/2001/XMLSchema#dateType";;
+               break;
+       case TRACKER_PROPERTY_TYPE_RESOURCE:
+               type = "http://www.w3.org/2000/01/rdf-schema#Resource";;
+               break;
+       case TRACKER_PROPERTY_TYPE_LANGSTRING:
+               type = "http://www.w3.org/1999/02/22-rdf-syntax-ns#langString";;
+               break;
+       }
+
+       if (type)
+               sqlite3_result_text (context, type, -1, NULL);
+       else
+               sqlite3_result_null (context);
+}
+
 static void
 function_sparql_rand (sqlite3_context *context,
                       int              argc,
@@ -1805,6 +1855,9 @@ initialize_functions (TrackerDBInterface *db_interface)
                { "SparqlFloor", 1, SQLITE_ANY | SQLITE_DETERMINISTIC,
                  function_sparql_floor },
                { "SparqlRand", 0, SQLITE_ANY, function_sparql_rand },
+               /* Types */
+               { "SparqlDataType", 1, SQLITE_ANY | SQLITE_DETERMINISTIC,
+                 function_sparql_data_type },
                /* UUID */
                { "SparqlUUID", 0, SQLITE_ANY, function_sparql_uuid },
                { "SparqlBNODE", -1, SQLITE_ANY | SQLITE_DETERMINISTIC, function_sparql_uuid },