/* -*- mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*- */
/* cc-time-editor.c
 *
 * Copyright 2020 Purism SPC
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Author(s):
 *   Mohammed Sadiq <sadiq@sadiqpk.org>
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 */

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "cc-time-editor"

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#define GNOME_DESKTOP_USE_UNSTABLE_API
#include <libgnome-desktop/gnome-wall-clock.h>
#include <gtk/gtk.h>
#include <glib/gi18n.h>

#include "cc-time-entry.h"
#include "cc-time-editor.h"


#define TIMEOUT_INITIAL  500
#define TIMEOUT_REPEAT    50

#define FILECHOOSER_SCHEMA "org.gtk.Settings.FileChooser"
#define CLOCK_SCHEMA       "org.gnome.desktop.interface"
#define CLOCK_FORMAT_KEY   "clock-format"
#define SECONDS_PER_MINUTE  (60)
#define SECONDS_PER_HOUR    (60 * 60)
#define SECONDS_PER_DAY     (60 * 60 * 24)


struct _CcTimeEditor
{
  GtkBin     parent_instance;

  GtkButton *am_pm_button;
  GtkStack  *am_pm_stack;
  GtkLabel  *am_label;
  GtkLabel  *pm_label;
  GtkButton *hour_up_button;
  GtkButton *hour_down_button;
  GtkButton *minute_up_button;
  GtkButton *minute_down_button;
  CcTimeEntry *time_entry;

  GtkButton *clicked_button; /* The button currently being clicked */
  GSettings *clock_settings;
  GSettings *filechooser_settings;

  guint      timer_id;
};

G_DEFINE_TYPE (CcTimeEditor, cc_time_editor, GTK_TYPE_BIN)


enum {
  TIME_CHANGED,
  N_SIGNALS
};

static guint signals[N_SIGNALS];

static void
time_editor_clock_changed_cb (CcTimeEditor *self)
{
  GDesktopClockFormat value;
  gboolean is_am_pm;

  g_assert (CC_IS_TIME_EDITOR (self));

  value = g_settings_get_enum (self->clock_settings, CLOCK_FORMAT_KEY);

  is_am_pm = value == G_DESKTOP_CLOCK_FORMAT_12H;
  cc_time_entry_set_am_pm (self->time_entry, is_am_pm);
  gtk_widget_set_visible (GTK_WIDGET (self->am_pm_button), is_am_pm);

  if (is_am_pm)
    {
      if (cc_time_entry_get_is_am (self->time_entry))
        gtk_stack_set_visible_child (self->am_pm_stack, GTK_WIDGET (self->am_label));
      else
        gtk_stack_set_visible_child (self->am_pm_stack, GTK_WIDGET (self->pm_label));
    }
}

static void
time_editor_time_changed_cb (CcTimeEditor *self)
{
  g_assert (CC_IS_TIME_EDITOR (self));

  g_signal_emit (self, signals[TIME_CHANGED], 0);
}

static void
editor_change_time_clicked_cb (CcTimeEditor *self,
                               GtkButton    *button)
{
  g_assert (CC_IS_TIME_EDITOR (self));

  if (button == NULL)
    return;

  if (button == self->hour_up_button)
    {
      gtk_editable_set_position (GTK_EDITABLE (self->time_entry), 0);
      g_signal_emit_by_name (self->time_entry, "change-value", GTK_SCROLL_STEP_UP);
    }
  else if (button == self->hour_down_button)
    {
      gtk_editable_set_position (GTK_EDITABLE (self->time_entry), 0);
      g_signal_emit_by_name (self->time_entry, "change-value", GTK_SCROLL_STEP_DOWN);
    }
  else if (button == self->minute_up_button)
    {
      gtk_editable_set_position (GTK_EDITABLE (self->time_entry), 3);
      g_signal_emit_by_name (self->time_entry, "change-value", GTK_SCROLL_STEP_UP);
    }
  else if (button == self->minute_down_button)
    {
      gtk_editable_set_position (GTK_EDITABLE (self->time_entry), 3);
      g_signal_emit_by_name (self->time_entry, "change-value", GTK_SCROLL_STEP_DOWN);
    }
}

static gboolean
editor_change_time_repeat (CcTimeEditor *self)
{
  if (self->clicked_button == NULL)
    {
      self->timer_id = 0;

      return G_SOURCE_REMOVE;
    }

  editor_change_time_clicked_cb (self, self->clicked_button);

  return G_SOURCE_CONTINUE;
}

static gboolean
editor_change_time_cb (CcTimeEditor *self)
{
  g_assert (CC_IS_TIME_EDITOR (self));
  g_clear_handle_id (&self->timer_id, g_source_remove);

  editor_change_time_clicked_cb (self, self->clicked_button);
  self->timer_id = g_timeout_add (TIMEOUT_REPEAT,
                                  (GSourceFunc)editor_change_time_repeat,
                                  self);
  return G_SOURCE_REMOVE;
}

static gboolean
editor_change_time_pressed_cb (CcTimeEditor *self,
                               GdkEvent     *event,
                               GtkButton    *button)
{
  g_assert (CC_IS_TIME_EDITOR (self));

  self->clicked_button = button;
  /* Keep changing time until the press is released */
  self->timer_id = g_timeout_add (TIMEOUT_INITIAL,
                                  (GSourceFunc)editor_change_time_cb,
                                  self);
  editor_change_time_clicked_cb (self, button);
  return FALSE;
}

static gboolean
editor_change_time_released_cb (CcTimeEditor *self)
{
  self->clicked_button = NULL;
  g_clear_handle_id (&self->timer_id, g_source_remove);

  return FALSE;
}

static void
editor_am_pm_button_clicked_cb (CcTimeEditor *self)
{
  gboolean is_am;

  g_assert (CC_IS_TIME_EDITOR (self));
  g_assert (cc_time_entry_get_am_pm (self->time_entry));

  is_am = cc_time_entry_get_is_am (self->time_entry);
  /* Toggle AM PM */
  cc_time_entry_set_is_am (self->time_entry, !is_am);
  time_editor_clock_changed_cb (self);
}

static void
editor_am_pm_stack_changed_cb (CcTimeEditor *self)
{
  AtkObject *accessible;
  GtkWidget *label;
  const gchar *text;

  g_assert (CC_IS_TIME_EDITOR (self));

  accessible = gtk_widget_get_accessible (GTK_WIDGET (self->am_pm_button));
  if (accessible == NULL)
    return;

  label = gtk_stack_get_visible_child (self->am_pm_stack);
  text = gtk_label_get_text (GTK_LABEL (label));
  atk_object_set_name (accessible, text);
}

static void
cc_time_editor_constructed (GObject *object)
{
  CcTimeEditor *self = (CcTimeEditor *)object;
  GDateTime *date;
  char *label;

  G_OBJECT_CLASS (cc_time_editor_parent_class)->constructed (object);

  /* Set localized identifier for AM */
  date = g_date_time_new_utc (1, 1, 1, 0, 0, 0);
  label = g_date_time_format (date, "%p");
  gtk_label_set_label (self->am_label, label);
  g_date_time_unref (date);
  g_free (label);

  /* Set localized identifier for PM */
  date = g_date_time_new_utc (1, 1, 1, 12, 0, 0);
  label = g_date_time_format (date, "%p");
  gtk_label_set_label (self->pm_label, label);
  g_date_time_unref (date);
  g_free (label);
}

static void
cc_time_editor_finalize (GObject *object)
{
  CcTimeEditor *self = (CcTimeEditor *)object;

  g_clear_handle_id (&self->timer_id, g_source_remove);
  g_clear_object (&self->clock_settings);
  g_clear_object (&self->filechooser_settings);

  G_OBJECT_CLASS (cc_time_editor_parent_class)->finalize (object);
}

static void
cc_time_editor_class_init (CcTimeEditorClass *klass)
{
  GObjectClass   *object_class = G_OBJECT_CLASS (klass);
  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);

  object_class->constructed = cc_time_editor_constructed;
  object_class->finalize = cc_time_editor_finalize;

  signals[TIME_CHANGED] =
    g_signal_new ("time-changed",
                  G_TYPE_FROM_CLASS (klass),
                  G_SIGNAL_RUN_FIRST,
                  0, NULL, NULL,
                  NULL,
                  G_TYPE_NONE, 0);

  gtk_widget_class_set_template_from_resource (widget_class,
                                               "/org/gnome/control-center/"
                                               "common/cc-time-editor.ui");

  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, am_pm_button);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, am_pm_stack);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, am_label);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, pm_label);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, hour_up_button);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, hour_down_button);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, minute_up_button);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, minute_down_button);
  gtk_widget_class_bind_template_child (widget_class, CcTimeEditor, time_entry);

  gtk_widget_class_bind_template_callback (widget_class, editor_change_time_pressed_cb);
  gtk_widget_class_bind_template_callback (widget_class, editor_change_time_released_cb);
  gtk_widget_class_bind_template_callback (widget_class, editor_am_pm_button_clicked_cb);
  gtk_widget_class_bind_template_callback (widget_class, editor_am_pm_stack_changed_cb);

  g_type_ensure (CC_TYPE_TIME_ENTRY);
}

static void
cc_time_editor_init (CcTimeEditor *self)
{
  gtk_widget_init_template (GTK_WIDGET (self));

  self->clock_settings = g_settings_new (CLOCK_SCHEMA);
  self->filechooser_settings = g_settings_new (FILECHOOSER_SCHEMA);

  g_signal_connect_object (self->clock_settings, "changed::" CLOCK_FORMAT_KEY,
                           G_CALLBACK (time_editor_clock_changed_cb), self,
                           G_CONNECT_SWAPPED);
  g_signal_connect_swapped (self->time_entry, "time-changed",
                            G_CALLBACK (time_editor_time_changed_cb), self);
  time_editor_clock_changed_cb (self);
}

CcTimeEditor *
cc_time_editor_new (void)
{
  return g_object_new (CC_TYPE_TIME_EDITOR, NULL);
}

void
cc_time_editor_set_time (CcTimeEditor *self,
                         guint         hour,
                         guint         minute)
{
  g_return_if_fail (CC_IS_TIME_EDITOR (self));

  cc_time_entry_set_time (self->time_entry, hour, minute);
}

guint
cc_time_editor_get_hour (CcTimeEditor *self)
{
  g_return_val_if_fail (CC_IS_TIME_EDITOR (self), 0);

  return cc_time_entry_get_hour (self->time_entry);
}

guint
cc_time_editor_get_minute (CcTimeEditor *self)
{
  g_return_val_if_fail (CC_IS_TIME_EDITOR (self), 0);

  return cc_time_entry_get_minute (self->time_entry);
}

gboolean
cc_time_editor_get_am_pm (CcTimeEditor *self)
{
  g_return_val_if_fail (CC_IS_TIME_EDITOR (self), TRUE);

  return TRUE;
}

void
cc_time_editor_set_am_pm (CcTimeEditor *self,
                          gboolean      is_am_pm)
{
  g_return_if_fail (CC_IS_TIME_EDITOR (self));

  cc_time_entry_set_am_pm (self->time_entry, is_am_pm);
}