/* ide-terminal.c
 *
 * Copyright 2016-2019 Christian Hergert <christian@hergert.me>
 *
 * 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 3 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/>.
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 */

#define G_LOG_DOMAIN "ide-terminal"

#include "config.h"

#include <glib/gi18n.h>

#include <libide-gui.h>

#include "ide-terminal.h"
#include "ide-terminal-search.h"

#define BUILDER_PCRE2_MULTILINE 0x00000400u
#define BUILDER_PCRE2_UCP 0x00020000u

typedef struct
{
  GtkPopover *popover;
  GSettings  *settings;
  char       *url;
  GdkRGBA     bg;
  GdkRGBA     fg;
} IdeTerminalPrivate;

typedef struct
{
  IdeTerminal *terminal;
  GdkEvent   *event;
} PopupInfo;

typedef struct
{
  gint line;
  gint column;
} Position;

G_DEFINE_TYPE_WITH_PRIVATE (IdeTerminal, ide_terminal, VTE_TYPE_TERMINAL)

/* From vteapp.c */
#define DINGUS1 "(((gopher|news|telnet|nntp|file|http|ftp|https)://)|(www|ftp)[-A-Za-z0-9]*\\.)[-A-Za-z0-9\\.]+(:[0-9]*)?"
#define DINGUS2 DINGUS1 "/[-A-Za-z0-9_\\$\\.\\+\\!\\*\\(\\),;:@&=\\?/~\\#\\%]*[^]'\\.}>\\) ,\\\"]"
#define FILENAME_PLUS_LOCATION "(?<filename>[[:alnum:]\\+\\-\\.\\/_]+):(?<line>\\d+):(?<column>\\d+)"

static const gchar *url_regexes[] = { DINGUS1, DINGUS2, FILENAME_PLUS_LOCATION };
static GRegex *filename_regex;
static const GdkRGBA solarized_palette[] = {
  /*
   * Solarized palette (1.0.0beta2):
   * http://ethanschoonover.com/solarized
   */
  { 0.02745,  0.211764, 0.258823, 1 },
  { 0.862745, 0.196078, 0.184313, 1 },
  { 0.521568, 0.6,      0,        1 },
  { 0.709803, 0.537254, 0,        1 },
  { 0.149019, 0.545098, 0.823529, 1 },
  { 0.82745,  0.211764, 0.509803, 1 },
  { 0.164705, 0.631372, 0.596078, 1 },
  { 0.933333, 0.909803, 0.835294, 1 },
  { 0,        0.168627, 0.211764, 1 },
  { 0.796078, 0.294117, 0.086274, 1 },
  { 0.345098, 0.431372, 0.458823, 1 },
  { 0.396078, 0.482352, 0.513725, 1 },
  { 0.513725, 0.580392, 0.588235, 1 },
  { 0.423529, 0.443137, 0.768627, 1 },
  { 0.57647,  0.631372, 0.631372, 1 },
  { 0.992156, 0.964705, 0.890196, 1 },
};

void
ide_terminal_get_colors (IdeTerminal *self,
                         GdkRGBA     *bg,
                         GdkRGBA     *fg)
{
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);

  g_return_if_fail (IDE_IS_TERMINAL (self));

  if (bg)
    *bg = priv->bg;

  if (fg)
    *fg = priv->fg;
}

static void
ide_terminal_css_changed (GtkWidget         *widget,
                          GtkCssStyleChange *change)
{
  IdeTerminal *self = (IdeTerminal *)widget;
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);
  GtkStyleContext *style_context;
  GdkRGBA fg;
  GdkRGBA bg;

  g_assert (IDE_IS_TERMINAL (widget));

  style_context = gtk_widget_get_style_context (widget);

  if (!gtk_style_context_lookup_color (style_context, "window_fg_color", &fg))
    gdk_rgba_parse (&fg, "#eeeeec");

  if (!gtk_style_context_lookup_color (style_context, "window_bg_color", &bg))
    gdk_rgba_parse (&bg, "#242424");

  vte_terminal_set_colors (VTE_TERMINAL (widget),
                           &fg, &bg,
                           solarized_palette, G_N_ELEMENTS (solarized_palette));

  priv->fg = fg;
  priv->bg = bg;
}

static void
ide_terminal_update_clipboard_actions (IdeTerminal *self)
{
  GdkClipboard *clipboard;
  gboolean can_paste;
  gboolean has_selection;

  g_assert (IDE_IS_TERMINAL (self));

  clipboard = gtk_widget_get_clipboard (GTK_WIDGET (self));
  can_paste = gdk_content_formats_contain_gtype (gdk_clipboard_get_formats (clipboard), G_TYPE_STRING);
  has_selection = vte_terminal_get_has_selection (VTE_TERMINAL (self));

  gtk_widget_action_set_enabled (GTK_WIDGET (self), "clipboard.copy", has_selection);
  gtk_widget_action_set_enabled (GTK_WIDGET (self), "clipboard.paste", can_paste);
}

static char *
ide_terminal_get_pattern_at_coords (IdeTerminal *self,
                                    double       x,
                                    double       y)
{
  g_autofree gchar *pattern = NULL;
  glong cell_width;
  glong cell_height;
  glong column, row;
  int tag = 0;

  g_assert (IDE_IS_TERMINAL (self));

  cell_width = vte_terminal_get_char_width (VTE_TERMINAL (self));
  cell_height = vte_terminal_get_char_height (VTE_TERMINAL (self));

  /* crappy way to do this, but i dont see another option right
   * now given we have to go through deprecated APIs in Vte
   * until it gets things together for GTK 4.
   */
  column = x / cell_width;
  row = y / cell_height;

  /* no other option in VTE for GTK 4 right now */
  G_GNUC_BEGIN_IGNORE_DEPRECATIONS
  pattern = vte_terminal_match_check (VTE_TERMINAL (self), column, row, &tag);
  G_GNUC_END_IGNORE_DEPRECATIONS

  return g_steal_pointer (&pattern);
}

static void
ide_terminal_update_url_actions (IdeTerminal *self,
                                 double       x,
                                 double       y)
{
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);
  g_autofree char *pattern = NULL;

  g_assert (IDE_IS_TERMINAL (self));

  pattern = ide_terminal_get_pattern_at_coords (self, x, y);

  gtk_widget_action_set_enabled (GTK_WIDGET (self), "clipboard.copy-link", pattern != NULL);
  gtk_widget_action_set_enabled (GTK_WIDGET (self), "terminal.open-link", pattern != NULL);

  ide_set_string (&priv->url, pattern);
}

static gboolean
clear_url_actions_cb (gpointer data)
{
  IdeTerminal *self = data;

  gtk_widget_action_set_enabled (GTK_WIDGET (self), "clipboard.copy-link", FALSE);
  gtk_widget_action_set_enabled (GTK_WIDGET (self), "terminal.open-link", FALSE);

  return G_SOURCE_REMOVE;
}

static void
ide_terminal_popover_closed_cb (IdeTerminal *self,
                                GtkPopover  *popover)
{
  g_assert (IDE_IS_TERMINAL (self));
  g_assert (GTK_IS_POPOVER (popover));

  g_idle_add_full (G_PRIORITY_LOW,
                   clear_url_actions_cb,
                   g_object_ref (self),
                   g_object_unref);
}

static void
ide_terminal_popup (IdeTerminal *self,
                    double       x,
                    double       y)
{
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);

  g_assert (IDE_IS_TERMINAL (self));

  ide_terminal_update_clipboard_actions (self);
  ide_terminal_update_url_actions (self, x, y);

  if (priv->popover == NULL)
    {
      GMenu *menu = ide_application_get_menu_by_id (IDE_APPLICATION_DEFAULT, "ide-terminal-page-popup-menu");

      priv->popover = GTK_POPOVER (gtk_popover_menu_new_from_model (G_MENU_MODEL (menu)));
      gtk_popover_set_has_arrow (priv->popover, FALSE);
      gtk_widget_set_halign (GTK_WIDGET (priv->popover), GTK_ALIGN_END);
      gtk_widget_set_parent (GTK_WIDGET (priv->popover), GTK_WIDGET (self));

      g_signal_connect_object (priv->popover,
                               "closed",
                               G_CALLBACK (ide_terminal_popover_closed_cb),
                               self,
                               G_CONNECT_SWAPPED);
    }

  gtk_popover_set_pointing_to (priv->popover,
                               &(GdkRectangle) { x, y, 1, 1 });

  gtk_popover_popup (priv->popover);
}

static void
ide_terminal_click_pressed_cb (IdeTerminal     *self,
                               int              n_presses,
                               double           x,
                               double           y,
                               GtkGestureClick *click)
{
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);
  int button;

  IDE_ENTRY;

  g_assert (IDE_IS_TERMINAL (self));
  g_assert (GTK_IS_GESTURE_CLICK (click));

  ide_terminal_update_url_actions (self, x, y);

  button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (click));

  if (button == 1)
    {
      if (priv->url != NULL)
        {
          gtk_widget_activate_action (GTK_WIDGET (self), "terminal.open-link", NULL);
          gtk_gesture_set_state (GTK_GESTURE (click), GTK_EVENT_SEQUENCE_CLAIMED);
        }
    }
  else if (button == 3)
    {
      if (!gtk_widget_has_focus (GTK_WIDGET (self)))
        gtk_widget_grab_focus (GTK_WIDGET (self));

      ide_terminal_popup (self, x, y);

      gtk_gesture_set_state (GTK_GESTURE (click), GTK_EVENT_SEQUENCE_CLAIMED);
    }

  IDE_EXIT;
}

static void
copy_link_address_action (GtkWidget  *widget,
                          const char *action_name,
                          GVariant   *param)
{
  IdeTerminal *self = (IdeTerminal *)widget;
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);

  g_assert (IDE_IS_TERMINAL (self));
  g_assert (priv->url != NULL);

  if (!ide_str_empty0 (priv->url))
    gdk_clipboard_set_text (gtk_widget_get_clipboard (GTK_WIDGET (self)), priv->url);
}

static void
ide_terminal_open_link_resolve_cb (GObject      *object,
                                   GAsyncResult *result,
                                   gpointer      user_data)
{
  IdeWorkbench *workbench = (IdeWorkbench *)object;
  g_autoptr(GFile) file = NULL;
  Position *pos = user_data;

  g_assert (IDE_IS_MAIN_THREAD ());
  g_assert (IDE_IS_WORKBENCH (workbench));
  g_assert (G_IS_ASYNC_RESULT (result));

  if ((file = ide_workbench_resolve_file_finish (workbench, result, NULL)))
    ide_workbench_open_at_async (workbench,
                                 file,
                                 "editor",
                                 pos->line,
                                 pos->column,
                                 IDE_BUFFER_OPEN_FLAGS_NONE,
                                 NULL, NULL, NULL, NULL);

  g_slice_free (Position, pos);
}

static void
open_link_action (GtkWidget  *widget,
                  const char *action_name,
                  GVariant   *param)
{
  IdeTerminal *self = (IdeTerminal *)widget;
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);
  g_autoptr(GMatchInfo) match = NULL;
  g_autofree char *filename = NULL;
  g_autofree char *line = NULL;
  g_autofree char *column = NULL;
  GtkApplication *app;
  GtkWindow *focused_window;

  g_assert (IDE_IS_TERMINAL (self));

  if (ide_str_empty0 (priv->url))
    return;

  if (g_regex_match (filename_regex, priv->url, 0, &match) &&
      (filename = g_match_info_fetch (match, 1)) &&
      (line = g_match_info_fetch (match, 2)) &&
      (column = g_match_info_fetch (match, 3)))
    {
      IdeWorkbench *workbench = ide_widget_get_workbench (GTK_WIDGET (self));
      gint64 lineno = g_ascii_strtoull (line, NULL, 10);
      gint64 columnno = g_ascii_strtoull (column, NULL, 10);
      Position pos = {
        MAX (lineno, 1) - 1,
        MAX (columnno, 1) - 1,
      };

      ide_workbench_resolve_file_async (workbench,
                                        filename,
                                        NULL,
                                        ide_terminal_open_link_resolve_cb,
                                        g_slice_dup (Position, &pos));

      return;
    }

  if ((app = GTK_APPLICATION (g_application_get_default ())) &&
      (focused_window = gtk_application_get_active_window (app)))
    ide_gtk_show_uri_on_window (focused_window,
                                priv->url,
                                g_get_monotonic_time (),
                                NULL);
}

static GtkWidget *
find_child_typed (GtkWidget *parent,
                  GType      child_type)
{
  for (GtkWidget *child = gtk_widget_get_first_child (parent);
       child;
       child = gtk_widget_get_next_sibling (child))
    {
      if (g_type_is_a (G_OBJECT_TYPE (child), child_type))
        return child;
    }

  return NULL;
}

static void
ide_terminal_search_reveal (GtkWidget  *widget,
                            const char *action_name,
                            GVariant   *param)
{
  IdeTerminal *self = (IdeTerminal *)widget;
  GtkWidget *parent_overlay;

  g_assert (IDE_IS_TERMINAL (self));

  parent_overlay = gtk_widget_get_ancestor (GTK_WIDGET (self), GTK_TYPE_OVERLAY);

  if (parent_overlay != NULL)
    {
      IdeTerminalSearch *search = IDE_TERMINAL_SEARCH (find_child_typed (parent_overlay, IDE_TYPE_TERMINAL_SEARCH));

      if (search != NULL)
        {
          GtkRevealer *revealer = ide_terminal_search_get_revealer (search);

          if (!gtk_revealer_get_child_revealed (revealer))
            gtk_revealer_set_reveal_child (revealer, TRUE);
        }
    }
}

static void
ide_terminal_font_changed (IdeTerminal *self,
                           const gchar *key,
                           GSettings   *settings)
{
  PangoFontDescription *font_desc = NULL;
  g_autofree gchar *font_name = NULL;

  g_assert (IDE_IS_TERMINAL (self));
  g_assert (G_IS_SETTINGS (settings));

  font_name = g_settings_get_string (settings, "font-name");

  if (font_name != NULL)
    font_desc = pango_font_description_from_string (font_name);

  vte_terminal_set_font (VTE_TERMINAL (self), font_desc);
  g_clear_pointer (&font_desc, pango_font_description_free);
}

static void
ide_terminal_size_allocate (GtkWidget *widget,
                            int        width,
                            int        height,
                            int        baseline)
{
  IdeTerminal *self = (IdeTerminal *)widget;
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);
  int char_width, char_height;
  int columns, rows;

  GTK_WIDGET_CLASS (ide_terminal_parent_class)->size_allocate (widget, width, height, baseline);

  char_width = vte_terminal_get_char_width (VTE_TERMINAL (self));
  char_height = vte_terminal_get_char_height (VTE_TERMINAL (self));
  if (char_width == 0 || char_height == 0)
    return;

  columns = width / char_width;
  rows = height / char_height;
  if (columns < 2 || rows < 2)
    return;

  vte_terminal_set_size (VTE_TERMINAL (self), columns, rows);

  if (priv->popover)
    gtk_popover_present (priv->popover);
}

static void
update_scrollback_cb (IdeTerminal *self,
                      const char  *key,
                      GSettings   *settings)
{
  gboolean limit_scrollback;
  guint scrollback_lines;

  g_assert (IDE_IS_TERMINAL (self));
  g_assert (G_IS_SETTINGS (settings));

  limit_scrollback = g_settings_get_boolean (settings, "limit-scrollback");
  scrollback_lines = g_settings_get_uint (settings, "scrollback-lines");

  if (limit_scrollback)
    vte_terminal_set_scrollback_lines (VTE_TERMINAL (self), scrollback_lines);
  else
    vte_terminal_set_scrollback_lines (VTE_TERMINAL (self), -1);
}

static void
select_all_action (GtkWidget  *widget,
                   const char *action_name,
                   GVariant   *param)
{
  g_assert (IDE_IS_TERMINAL (widget));
  g_assert (g_variant_is_of_type (param, G_VARIANT_TYPE_BOOLEAN));

  if (g_variant_get_boolean (param))
    vte_terminal_select_all (VTE_TERMINAL (widget));
  else
    vte_terminal_unselect_all (VTE_TERMINAL (widget));
}

static void
copy_clipboard_action (GtkWidget  *widget,
                       const char *action_name,
                       GVariant   *param)
{
  GdkClipboard *clipboard = gtk_widget_get_clipboard (widget);
  g_autofree char *text = vte_terminal_get_text_selected (VTE_TERMINAL (widget), VTE_FORMAT_TEXT);
  gdk_clipboard_set_text (clipboard, text);
}

static void
ide_terminal_read_text_cb (GObject      *object,
                           GAsyncResult *result,
                           gpointer      user_data)
{
  GdkClipboard *clipboard = (GdkClipboard *)object;
  g_autoptr(IdeTerminal) self = user_data;
  g_autofree char *text = NULL;

  g_assert (GDK_IS_CLIPBOARD (clipboard));
  g_assert (G_IS_ASYNC_RESULT (result));
  g_assert (IDE_IS_TERMINAL (self));

  if ((text = gdk_clipboard_read_text_finish (clipboard, result, NULL)))
    vte_terminal_paste_text (VTE_TERMINAL (self), text);
}

static void
paste_clipboard_action (GtkWidget  *widget,
                        const char *action_name,
                        GVariant   *param)
{
  GdkClipboard *clipboard = gtk_widget_get_clipboard (widget);

  gdk_clipboard_read_text_async (clipboard,
                                 NULL,
                                 ide_terminal_read_text_cb,
                                 g_object_ref (widget));
}

static void
ide_terminal_selection_changed (VteTerminal *terminal)
{
  ide_terminal_update_clipboard_actions (IDE_TERMINAL (terminal));
}

static void
ide_terminal_dispose (GObject *object)
{
  IdeTerminal *self = (IdeTerminal *)object;
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);

  g_clear_pointer ((GtkWidget **)&priv->popover, gtk_widget_unparent);

  g_clear_object (&priv->settings);
  g_clear_pointer (&priv->url, g_free);

  G_OBJECT_CLASS (ide_terminal_parent_class)->dispose (object);
}

static void
ide_terminal_class_init (IdeTerminalClass *klass)
{
  GObjectClass *object_class = G_OBJECT_CLASS (klass);
  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
  VteTerminalClass *terminal_class = VTE_TERMINAL_CLASS (klass);

  object_class->dispose = ide_terminal_dispose;

  widget_class->css_changed = ide_terminal_css_changed;
  widget_class->size_allocate = ide_terminal_size_allocate;

  terminal_class->selection_changed = ide_terminal_selection_changed;

  filename_regex = g_regex_new (FILENAME_PLUS_LOCATION, 0, 0, NULL);
  g_assert (filename_regex != NULL);

  gtk_widget_class_install_action (widget_class, "clipboard.copy", NULL, copy_clipboard_action);
  gtk_widget_class_install_action (widget_class, "clipboard.copy-link", NULL, copy_link_address_action);
  gtk_widget_class_install_action (widget_class, "clipboard.paste", NULL, paste_clipboard_action);
  gtk_widget_class_install_action (widget_class, "terminal.open-link", NULL, open_link_action);
  gtk_widget_class_install_action (widget_class, "terminal.search", NULL, ide_terminal_search_reveal);
  gtk_widget_class_install_action (widget_class, "terminal.select-all", "b", select_all_action);

  gtk_widget_class_add_binding_action (widget_class, GDK_KEY_c, GDK_CONTROL_MASK|GDK_SHIFT_MASK, "clipboard.copy", NULL);
  gtk_widget_class_add_binding_action (widget_class, GDK_KEY_v, GDK_CONTROL_MASK|GDK_SHIFT_MASK, "clipboard.paste", NULL);
}

static void
ide_terminal_init (IdeTerminal *self)
{
  IdeTerminalPrivate *priv = ide_terminal_get_instance_private (self);
  GtkEventController *gesture;

  gesture = GTK_EVENT_CONTROLLER (gtk_gesture_click_new ());
  gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (gesture), 0);
  gtk_event_controller_set_propagation_phase (gesture, GTK_PHASE_CAPTURE);
  g_signal_connect_object (gesture,
                           "pressed",
                           G_CALLBACK (ide_terminal_click_pressed_cb),
                           self,
                           G_CONNECT_SWAPPED);
  gtk_widget_add_controller (GTK_WIDGET (self), g_steal_pointer (&gesture));

  for (guint i = 0; i < G_N_ELEMENTS (url_regexes); i++)
    {
      g_autoptr(VteRegex) regex = NULL;
      const gchar *pattern = url_regexes[i];
      gint tag;

      regex = vte_regex_new_for_match (pattern, strlen (pattern),
                                       VTE_REGEX_FLAGS_DEFAULT | BUILDER_PCRE2_MULTILINE | BUILDER_PCRE2_UCP,
                                       NULL);
      tag = vte_terminal_match_add_regex (VTE_TERMINAL (self), regex, 0);
      vte_terminal_match_set_cursor_name (VTE_TERMINAL (self), tag, "hand2");
    }

  priv->settings = g_settings_new ("org.gnome.builder.terminal");
  g_settings_bind (priv->settings, "allow-bold", self, "allow-bold", G_SETTINGS_BIND_GET);
  g_settings_bind (priv->settings, "allow-hyperlink", self, "allow-hyperlink", G_SETTINGS_BIND_GET);
  g_settings_bind (priv->settings, "scroll-on-output", self, "scroll-on-output", G_SETTINGS_BIND_GET);
  g_settings_bind (priv->settings, "scroll-on-keystroke", self, "scroll-on-keystroke", G_SETTINGS_BIND_GET);
  g_signal_connect_object (priv->settings,
                           "changed::limit-scrollback",
                           G_CALLBACK (update_scrollback_cb),
                           self,
                           G_CONNECT_SWAPPED);
  g_signal_connect_object (priv->settings,
                           "changed::scrollback-lines",
                           G_CALLBACK (update_scrollback_cb),
                           self,
                           G_CONNECT_SWAPPED);
  g_signal_connect_object (priv->settings,
                           "changed::font-name",
                           G_CALLBACK (ide_terminal_font_changed),
                           self,
                           G_CONNECT_SWAPPED);
  ide_terminal_font_changed (self, NULL, priv->settings);
  update_scrollback_cb (self, "scrollback-lines", priv->settings);

  vte_terminal_set_enable_fallback_scrolling (VTE_TERMINAL (self), FALSE);
  vte_terminal_set_scroll_unit_is_pixels (VTE_TERMINAL (self), TRUE);
}

GtkWidget *
ide_terminal_new (void)
{
  return g_object_new (IDE_TYPE_TERMINAL, NULL);
}
