[libgdata] demos: Add a demo of Google Tasks

[Philip Withnall <pwithnall src gnome org>]

commit fd1451a33f32bfc208e799e0f81139b790e315d3
Author: Philip Withnall <withnall endlessm com>
Date:   Mon Feb 6 10:02:46 2017 +0100

    demos: Add a demo of Google Tasks
    
    This is a simple read-only demo of the Tasks service, similar to the
    Calendar demo.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=775813

 Makefile.am             |   33 +++++
 demos/tasks/tasks-cli.c |  350 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 383 insertions(+), 0 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index fd3e754..70633d3 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -634,6 +634,7 @@ CODE_COVERAGE_LCOV_OPTIONS = --base-directory $(abs_top_srcdir)
 noinst_PROGRAMS = \
        demos/youtube/youtube-cli \
        demos/calendar/calendar-cli \
+       demos/tasks/tasks-cli \
        $(NULL)
 
 if ENABLE_GOA
@@ -809,6 +810,38 @@ demos_calendar_calendar_cli_LDADD = \
        $(AM_LDADD) \
        $(NULL)
 
+demos_tasks_tasks_cli_SOURCES = \
+       demos/tasks/tasks-cli.c  \
+       $(NULL)
+
+demos_tasks_tasks_cli_CPPFLAGS = \
+       -I$(top_srcdir)/ \
+       -I$(top_srcdir)/gdata \
+       -DG_LOG_DOMAIN=\"tasks\" \
+       -DLIBGDATA_DISABLE_DEPRECATED \
+       $(DISABLE_DEPRECATED) \
+       $(AM_CPPFLAGS) \
+       $(NULL)
+
+demos_tasks_tasks_cli_CFLAGS = \
+       $(WARN_CFLAGS) \
+       $(GDATA_CFLAGS) \
+       $(GNOME_CFLAGS) \
+       $(AM_CFLAGS) \
+       $(NULL)
+
+demos_tasks_tasks_cli_LDFLAGS = \
+       $(WARN_LDFLAGS) \
+       $(AM_LDFLAGS) \
+       $(NULL)
+
+demos_tasks_tasks_cli_LDADD = \
+       $(top_builddir)/gdata/libgdata.la \
+       $(GDATA_LIBS) \
+       $(GNOME_LIBS) \
+       $(AM_LDADD) \
+       $(NULL)
+
 # Cleaning
 EXTRA_DIST += \
        autogen.sh              \
diff --git a/demos/tasks/tasks-cli.c b/demos/tasks/tasks-cli.c
new file mode 100644
index 0000000..c795761
--- /dev/null
+++ b/demos/tasks/tasks-cli.c
@@ -0,0 +1,350 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
+/*
+ * GData Client
+ * Copyright © 2017 Philip Withnall <philip tecnocode co uk>
+ *
+ * GData Client is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * GData Client is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GData Client.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <gdata/gdata.h>
+#include <locale.h>
+#include <string.h>
+
+#define CLIENT_ID "1074795795536-necvslvs0pchk65nf6ju4i6mniogg8fr.apps.googleusercontent.com"
+#define CLIENT_SECRET "8totRi50eo2Zfr3SD2DeNAzo"
+#define REDIRECT_URI "urn:ietf:wg:oauth:2.0:oob"
+
+static int
+print_usage (char *argv[])
+{
+       g_printerr ("%s: Usage — %s <subcommand>\n"
+                   "Subcommands:\n"
+                   "   tasklists\n"
+                   "   tasks <tasklist ID> [query string]\n",
+                   argv[0], argv[0]);
+       return -1;
+}
+
+static void
+print_tasklist (GDataTasksTasklist *tasklist)
+{
+       const gchar *id, *title, *description;
+
+       id = gdata_entry_get_id (GDATA_ENTRY (tasklist));
+       title = gdata_entry_get_title (GDATA_ENTRY (tasklist));
+       description = gdata_entry_get_summary (GDATA_ENTRY (tasklist));
+
+       g_print ("%s — %s\n", id, title);
+       g_print ("   Description:\n      %s\n", description);
+
+       g_print ("\n");
+}
+
+static const gchar *
+format_status (const gchar *status)
+{
+       if (g_strcmp0 (status, GDATA_TASKS_STATUS_NEEDS_ACTION) == 0)
+               return "needs action";
+       else if (g_strcmp0 (status, GDATA_TASKS_STATUS_COMPLETED) == 0)
+               return "completed";
+       else
+               return status;
+}
+
+static void
+print_task (GDataTasksTask *task)
+{
+       const gchar *title, *id, *description, *parent_id, *position, *notes;
+       const gchar *status;
+       GTimeVal date_published_tv = { 0, };
+       gchar *date_published = NULL;  /* owned */
+       GTimeVal due_tv = { 0, };
+       gchar *due = NULL;  /* owned */
+       GTimeVal completed_tv = { 0, };
+       gchar *completed = NULL;  /* owned */
+       gboolean is_deleted, is_hidden;
+
+       title = gdata_entry_get_title (GDATA_ENTRY (task));
+       id = gdata_entry_get_id (GDATA_ENTRY (task));
+       description = gdata_entry_get_content (GDATA_ENTRY (task));
+       date_published_tv.tv_sec = gdata_entry_get_published (GDATA_ENTRY (task));
+       date_published = g_time_val_to_iso8601 (&date_published_tv);
+       parent_id = gdata_tasks_task_get_parent (task);
+       position = gdata_tasks_task_get_position (task);
+       notes = gdata_tasks_task_get_notes (task);
+       status = gdata_tasks_task_get_status (task);
+       due_tv.tv_sec = gdata_tasks_task_get_due (task);
+       due = g_time_val_to_iso8601 (&due_tv);
+       completed_tv.tv_sec = gdata_tasks_task_get_completed (task);
+       completed = g_time_val_to_iso8601 (&completed_tv);
+       is_deleted = gdata_tasks_task_is_deleted (task);
+       is_hidden = gdata_tasks_task_is_hidden (task);
+
+       g_print ("%s — %s\n", id, title);
+       g_print ("   Published: %s\n", date_published_tv.tv_sec != 0 ? date_published : "unknown");
+       g_print ("   Status: %s\n", format_status (status));
+       g_print ("   Due: %s\n", due_tv.tv_sec != 0 ? due : "not set");
+       g_print ("   Completed: %s\n", completed_tv.tv_sec != 0 ? completed : "not yet");
+       g_print ("   Deleted? %s\n", is_deleted ? "Yes" : "No");
+       g_print ("   Hidden? %s\n", is_hidden ? "Yes" : "No");
+       g_print ("   Position: %s\n", position);
+       g_print ("   Parent ID: %s\n", parent_id);
+       g_print ("   Description:\n      %s\n", description);
+       g_print ("   Notes:\n      %s\n", notes);
+
+       g_print ("\n");
+
+       g_free (completed);
+       g_free (due);
+       g_free (date_published);
+}
+
+/* FIXME: Factor all this code out of all the demos */
+static GDataAuthorizer *
+create_authorizer (GError **error)
+{
+       GDataOAuth2Authorizer *authorizer = NULL;  /* owned */
+       gchar *uri = NULL;
+       gchar code[100];
+       GError *child_error = NULL;
+
+       /* Go through the interactive OAuth dance. */
+       authorizer = gdata_oauth2_authorizer_new (CLIENT_ID, CLIENT_SECRET,
+                                                 REDIRECT_URI,
+                                                 GDATA_TYPE_TASKS_SERVICE);
+
+       /* Get an authentication URI */
+       uri = gdata_oauth2_authorizer_build_authentication_uri (authorizer,
+                                                               NULL, FALSE);
+
+       /* Wait for the user to retrieve and enter the verifier. */
+       g_print ("Please navigate to the following URI and grant access:\n"
+                "   %s\n", uri);
+       g_print ("Enter verifier (EOF to abort): ");
+
+       g_free (uri);
+
+       if (scanf ("%100s", code) != 1) {
+               /* User chose to abort. */
+               g_print ("\n");
+               g_clear_object (&authorizer);
+               return NULL;
+       }
+
+       /* Authorise the token. */
+       gdata_oauth2_authorizer_request_authorization (authorizer, code, NULL,
+                                                      &child_error);
+
+       if (child_error != NULL) {
+               g_propagate_error (error, child_error);
+               g_clear_object (&authorizer);
+               return NULL;
+       }
+
+       return GDATA_AUTHORIZER (authorizer);
+}
+
+/* List all the user’s task-lists. */
+static int
+command_tasklists (int argc, char *argv[])
+{
+       GDataTasksService *service = NULL;
+       GDataTasksQuery *query = NULL;
+       GDataFeed *feed = NULL;
+       GList/*<unowned GDataTasksTasklist>*/ *entries;
+       GError *error = NULL;
+       gint retval = 0;
+       GDataAuthorizer *authorizer = NULL;
+
+       if (argc != 2) {
+               return print_usage (argv);
+       }
+
+       /* Authenticate and create a service. */
+       authorizer = create_authorizer (&error);
+
+       if (error != NULL) {
+               g_printerr ("%s: Error authenticating: %s\n",
+                           argv[0], error->message);
+               g_error_free (error);
+               retval = 1;
+               goto done;
+       } else if (authorizer == NULL) {
+               g_printerr ("%s: User chose to abort authentication.\n",
+                           argv[0]);
+               retval = 1;
+               goto done;
+       }
+
+       service = gdata_tasks_service_new (authorizer);
+       query = gdata_tasks_query_new (NULL);
+
+       feed = gdata_tasks_service_query_all_tasklists (service,
+                                                       GDATA_QUERY (query),
+                                                       NULL, NULL,
+                                                       NULL,
+                                                       &error);
+
+       if (error != NULL) {
+               g_printerr ("%s: Error querying tasklists: %s\n",
+                           argv[0], error->message);
+               g_error_free (error);
+               retval = 1;
+               goto done;
+       }
+
+       /* Print results. */
+       for (entries = gdata_feed_get_entries (feed); entries != NULL;
+            entries = entries->next) {
+               GDataTasksTasklist *tasklist;
+
+               tasklist = GDATA_TASKS_TASKLIST (entries->data);
+               print_tasklist (tasklist);
+       }
+
+       g_print ("Total of %u results.\n",
+                g_list_length (gdata_feed_get_entries (feed)));
+
+done:
+       g_clear_object (&feed);
+       g_clear_object (&query);
+       g_clear_object (&authorizer);
+       g_clear_object (&service);
+
+       return retval;
+}
+
+/* Query the tasks in a tasklist. */
+static int
+command_tasks (int argc, char *argv[])
+{
+       GDataTasksService *service = NULL;
+       GDataTasksTasklist *tasklist = NULL;
+       GDataTasksQuery *query = NULL;
+       GError *error = NULL;
+       gint retval = 0;
+       const gchar *query_string, *tasklist_id;
+       GDataAuthorizer *authorizer = NULL;
+       guint n_results;
+
+       if (argc < 3) {
+               return print_usage (argv);
+       }
+
+       tasklist_id = argv[2];
+       query_string = (argc > 3) ? argv[3] : NULL;
+
+       /* Authenticate and create a service. */
+       authorizer = create_authorizer (&error);
+
+       if (error != NULL) {
+               g_printerr ("%s: Error authenticating: %s\n",
+                           argv[0], error->message);
+               g_error_free (error);
+               retval = 1;
+               goto done;
+       } else if (authorizer == NULL) {
+               g_printerr ("%s: User chose to abort authentication.\n",
+                           argv[0]);
+               retval = 1;
+               goto done;
+       }
+
+       service = gdata_tasks_service_new (authorizer);
+       query = gdata_tasks_query_new (query_string);
+       gdata_query_set_max_results (GDATA_QUERY (query), 10);
+       tasklist = gdata_tasks_tasklist_new (tasklist_id);
+       n_results = 0;
+
+       while (TRUE) {
+               GList/*<unowned GDataTasksTask>*/ *entries, *l;
+               GDataFeed *feed = NULL;
+
+               feed = gdata_tasks_service_query_tasks (service, tasklist,
+                                                       GDATA_QUERY (query),
+                                                       NULL, NULL, NULL,
+                                                       &error);
+
+               if (error != NULL) {
+                       g_printerr ("%s: Error querying tasks: %s\n",
+                                   argv[0], error->message);
+                       g_error_free (error);
+                       retval = 1;
+                       goto done;
+               }
+
+               /* Print results. */
+               entries = gdata_feed_get_entries (feed);
+
+               if (entries == NULL) {
+                       retval = 0;
+                       g_object_unref (feed);
+                       break;
+               }
+
+               for (l = entries; l != NULL; l = l->next) {
+                       GDataTasksTask *task;
+
+                       task = GDATA_TASKS_TASK (l->data);
+                       print_task (task);
+                       n_results++;
+               }
+
+               gdata_query_next_page (GDATA_QUERY (query));
+               g_object_unref (feed);
+       }
+
+       g_print ("Total of %u results.\n", n_results);
+
+done:
+       g_clear_object (&query);
+       g_clear_object (&authorizer);
+       g_clear_object (&tasklist);
+       g_clear_object (&service);
+
+       return retval;
+}
+
+static const struct {
+       const gchar *command;
+       int (*handler_fn) (int argc, char **argv);
+} command_handlers[] = {
+       { "tasklists", command_tasklists },
+       { "tasks", command_tasks },
+};
+
+int
+main (int argc, char *argv[])
+{
+       guint i;
+       gint retval = -1;
+
+       setlocale (LC_ALL, "");
+
+       if (argc < 2) {
+               return print_usage (argv);
+       }
+
+       for (i = 0; i < G_N_ELEMENTS (command_handlers); i++) {
+               if (strcmp (argv[1], command_handlers[i].command) == 0) {
+                       retval = command_handlers[i].handler_fn (argc, argv);
+               }
+       }
+
+       if (retval == -1) {
+               retval = print_usage (argv);
+       }
+
+       return retval;
+}