/*
 * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
 *
 * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
 * Copyright (C) 2009, Guilhem Bonnefille <guilhem.bonnefille@gmail.com>
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <glib.h>
#include <glib/gstdio.h>
#include <glib/gprintf.h>
#include <glib/gi18n.h>

#include "viking.h"
#include "vikgototool.h"
#include "vikgoto.h"
#include "ui_util.h"

/* Compatibility */
#if ! GLIB_CHECK_VERSION(2,22,0)
#define g_mapped_file_unref g_mapped_file_free
#endif

static gchar *last_goto_str = NULL;
static VikCoord *last_coord = NULL;
static gchar *last_successful_goto_str = NULL;

static GList *goto_tools_list = NULL;

#define VIK_SETTINGS_GOTO_PROVIDER "goto_provider"
int last_goto_tool = -1;

void vik_goto_register ( VikGotoTool *tool )
{
  if ( IS_VIK_GOTO_TOOL( tool ) )
    goto_tools_list = g_list_append ( goto_tools_list, g_object_ref ( tool ) );
}

void vik_goto_unregister_all ()
{
  g_list_foreach ( goto_tools_list, (GFunc) g_object_unref, NULL );
}

gchar * a_vik_goto_get_search_string_for_this_place(VikWindow *vw)
{
  if (!last_coord)
    return NULL;

  VikViewport *vvp = vik_window_viewport(vw);
  const VikCoord *cur_center = vik_viewport_get_center(vvp);
  if (vik_coord_equals(cur_center, last_coord)) {
    return(last_successful_goto_str);
  }
  else
    return NULL;
}

static void display_no_tool(VikWindow *vw)
{
  GtkWidget *dialog = NULL;

  dialog = gtk_message_dialog_new ( GTK_WINDOW(vw), GTK_DIALOG_MODAL, GTK_MESSAGE_WARNING, GTK_BUTTONS_OK, _("No goto tool available.") );

  gtk_dialog_run ( GTK_DIALOG(dialog) );

  gtk_widget_destroy(dialog);
}

static gboolean prompt_try_again(VikWindow *vw, const gchar *msg)
{
  GtkWidget *dialog = NULL;
  gboolean ret = TRUE;

  dialog = gtk_dialog_new_with_buttons ( "", GTK_WINDOW(vw), 0, GTK_STOCK_OK, GTK_RESPONSE_ACCEPT, GTK_STOCK_CANCEL, GTK_RESPONSE_REJECT, NULL );
  gtk_window_set_title(GTK_WINDOW(dialog), _("goto"));

  GtkWidget *goto_label = gtk_label_new(msg);
  gtk_box_pack_start ( GTK_BOX(gtk_dialog_get_content_area(GTK_DIALOG(dialog))), goto_label, FALSE, FALSE, 5 );
  gtk_dialog_set_default_response ( GTK_DIALOG(dialog), GTK_RESPONSE_ACCEPT );
  gtk_widget_show_all(dialog);

  if ( gtk_dialog_run ( GTK_DIALOG(dialog) ) != GTK_RESPONSE_ACCEPT )
    ret = FALSE;

  gtk_widget_destroy(dialog);
  return ret;
}

static gint find_entry = -1;
static gint wanted_entry = -1;

static void find_provider (gpointer elem, gpointer user_data)
{
  const gchar *name = vik_goto_tool_get_label (elem);
  const gchar *provider = user_data;
  find_entry++;
  if (!strcmp(name, provider)) {
    wanted_entry = find_entry;
  }
}

/**
 * Setup last_goto_tool value
 */
static void get_provider ()
{
  // Use setting for the provider if available
  if ( last_goto_tool < 0 ) {
    find_entry = -1;
    wanted_entry = -1;
    gchar *provider = NULL;
    if ( a_settings_get_string ( VIK_SETTINGS_GOTO_PROVIDER, &provider ) ) {
      // Use setting
      if ( provider )
        g_list_foreach (goto_tools_list, find_provider, provider);
      // If not found set it to the first entry, otherwise use the entry
      last_goto_tool = ( wanted_entry < 0 ) ? 0 : wanted_entry;
    }
    else
      last_goto_tool = 0;
  }
}

static void
text_changed_cb (GtkEntry   *entry,
                 GParamSpec *pspec,
                 GtkWidget  *button)
{
  gboolean has_text = gtk_entry_get_text_length(entry) > 0;
  gtk_entry_set_icon_sensitive ( entry, GTK_ENTRY_ICON_SECONDARY, has_text );
  gtk_widget_set_sensitive ( button, has_text );
}

static gchar *a_prompt_for_goto_string(VikWindow *vw)
{
  GtkWidget *dialog = NULL;

  dialog = gtk_dialog_new_with_buttons ( "", GTK_WINDOW(vw), 0, GTK_STOCK_OK, GTK_RESPONSE_ACCEPT, GTK_STOCK_CANCEL, GTK_RESPONSE_REJECT, NULL );
  gtk_window_set_title(GTK_WINDOW(dialog), _("goto"));

  GtkWidget *tool_label = gtk_label_new(_("goto provider:"));
  GtkWidget *tool_list = vik_combo_box_text_new ();
  GList *current = g_list_first (goto_tools_list);
  while (current != NULL)
  {
    char *label = NULL;
    VikGotoTool *tool = current->data;
    label = vik_goto_tool_get_label (tool);
    vik_combo_box_text_append ( tool_list, label );
    current = g_list_next (current);
  }

  get_provider ();
  gtk_combo_box_set_active ( GTK_COMBO_BOX( tool_list ), last_goto_tool );

  GtkWidget *goto_label = gtk_label_new(_("Enter address or place name:"));
  GtkWidget *goto_entry = ui_entry_new ( last_goto_str, GTK_ENTRY_ICON_SECONDARY );

  // 'ok' when press return in the entry
  g_signal_connect_swapped (goto_entry, "activate", G_CALLBACK(a_dialog_response_accept), dialog);

#if GTK_CHECK_VERSION (2,20,0)
  GtkWidget *ok_button = gtk_dialog_get_widget_for_response ( GTK_DIALOG(dialog), GTK_RESPONSE_ACCEPT );
  text_changed_cb ( GTK_ENTRY(goto_entry), NULL, ok_button );
  g_signal_connect ( goto_entry, "notify::text", G_CALLBACK (text_changed_cb), ok_button );
#endif
  gtk_box_pack_start ( GTK_BOX(gtk_dialog_get_content_area(GTK_DIALOG(dialog))), tool_label, FALSE, FALSE, 5 );
  gtk_box_pack_start ( GTK_BOX(gtk_dialog_get_content_area(GTK_DIALOG(dialog))), tool_list, FALSE, FALSE, 5 );
  gtk_box_pack_start ( GTK_BOX(gtk_dialog_get_content_area(GTK_DIALOG(dialog))), goto_label, FALSE, FALSE, 5 );
  gtk_box_pack_start ( GTK_BOX(gtk_dialog_get_content_area(GTK_DIALOG(dialog))), goto_entry, FALSE, FALSE, 5 );
  gtk_dialog_set_default_response ( GTK_DIALOG(dialog), GTK_RESPONSE_ACCEPT );
  gtk_widget_show_all(dialog);

  // Ensure the text field has focus so we can start typing straight away
  gtk_widget_grab_focus ( goto_entry );

  if ( gtk_dialog_run ( GTK_DIALOG(dialog) ) != GTK_RESPONSE_ACCEPT ) {
    gtk_widget_destroy(dialog);
    return NULL;
  }
  
  // TODO check if list is empty
  last_goto_tool = gtk_combo_box_get_active ( GTK_COMBO_BOX(tool_list) );
  gchar *provider = vik_goto_tool_get_label ( g_list_nth_data (goto_tools_list, last_goto_tool) );
  a_settings_set_string ( VIK_SETTINGS_GOTO_PROVIDER, provider );

  gchar *goto_str = g_strdup ( gtk_entry_get_text ( GTK_ENTRY(goto_entry) ) );

  gtk_widget_destroy(dialog);

  if (goto_str[0] != '\0') {
    if (last_goto_str)
      g_free(last_goto_str);
    last_goto_str = g_strdup(goto_str);
  }

  return(goto_str);   /* goto_str needs to be freed by caller */
}

/**
 * Goto a place when we already have a string to search on
 *
 * Returns: %TRUE if a successful lookup
 */
static gboolean vik_goto_place ( VikWindow *vw, VikViewport *vvp, gchar* name, VikCoord *vcoord )
{
  // Ensure last_goto_tool is given a value
  get_provider ();

  if ( goto_tools_list ) {
    VikGotoTool *gototool = g_list_nth_data ( goto_tools_list, last_goto_tool );
    if ( gototool ) {
      if ( vik_goto_tool_get_coord ( gototool, vw, vvp, name, vcoord ) == 0 )
        return TRUE;
    }
  }
  return FALSE;
}

void a_vik_goto(VikWindow *vw, VikViewport *vvp)
{
  VikCoord new_center;
  gchar *s_str;
  gboolean more = TRUE;

  if (goto_tools_list == NULL)
  {
    /* Empty list */
    display_no_tool(vw);
    return;
  }

  do {
    s_str = a_prompt_for_goto_string(vw);
    if ((!s_str) || (s_str[0] == 0)) {
      more = FALSE;
    }
    else {
      int ans = vik_goto_tool_get_coord(g_list_nth_data (goto_tools_list, last_goto_tool), vw, vvp, s_str, &new_center);
      if ( ans == 0 ) {
        if (last_coord)
          g_free(last_coord);
        last_coord = g_malloc(sizeof(VikCoord));
        *last_coord = new_center;
        if (last_successful_goto_str)
          g_free(last_successful_goto_str);
        last_successful_goto_str = g_strdup(last_goto_str);
        vik_viewport_set_center_coord(vvp, &new_center, TRUE);
        more = FALSE;
      }
      else if ( ans == -1 ) {
        if (!prompt_try_again(vw, _("I don't know that place. Do you want another goto?")))
          more = FALSE;
      }
      else if (!prompt_try_again(vw, _("Service request failure. Do you want another goto?")))
        more = FALSE;
    }
    g_free(s_str);
  } while (more);
}

#define JSON_LATITUDE_PATTERN "\"geoplugin_latitude\":\""
#define JSON_LONGITUDE_PATTERN "\"geoplugin_longitude\":\""
#define JSON_CITY_PATTERN "\"geoplugin_city\":\""
#define JSON_COUNTRY_PATTERN "\"geoplugin_countryName\":\""

/**
 * Automatic attempt to find out where you are using:
 *   1. http://www.geoplugin.com ++
 *   2. if not specific enough fallback to using the default goto tool with a country name
 * ++ Using returned JSON information
 *  c.f. with googlesearch.c - similar implementation is used here
 *
 * returns:
 *   0 if failed to locate anything
 *   1 if exact latitude/longitude found
 *   2 if position only as precise as a city
 *   3 if position only as precise as a country
 * @name: Contains the name of place found. Free this string after use.
 */
gint a_vik_goto_where_am_i ( VikViewport *vvp, struct LatLon *ll, gchar **name )
{
  gint result = 0;
  *name = NULL;

  gchar *tmpname = a_download_uri_to_tmp_file ( "http://www.geoplugin.net/json.gp", NULL );
  //gchar *tmpname = g_strdup ("../test/www.geoplugin.net-slash-json.gp.result");
  if (!tmpname) {
    return result;
  }

  ll->lat = 0.0;
  ll->lon = 0.0;

  gchar *pat;
  GMappedFile *mf;
  gchar *ss;
  gint fragment_len;

  gchar lat_buf[32], lon_buf[32];
  lat_buf[0] = lon_buf[0] = '\0';
  gchar *country = NULL;
  gchar *city = NULL;

  if ((mf = g_mapped_file_new(tmpname, FALSE, NULL)) == NULL) {
    g_critical(_("couldn't map temp file"));
    goto tidy;
  }

  gsize len = g_mapped_file_get_length(mf);
  gchar *text = g_mapped_file_get_contents(mf);

  if ((pat = g_strstr_len(text, len, JSON_COUNTRY_PATTERN))) {
    pat += strlen(JSON_COUNTRY_PATTERN);
    fragment_len = 0;
    ss = pat;
    while (*pat != '"') {
      fragment_len++;
      pat++;
    }
    country = g_strndup(ss, fragment_len);
  }

  if ((pat = g_strstr_len(text, len, JSON_CITY_PATTERN))) {
    pat += strlen(JSON_CITY_PATTERN);
    fragment_len = 0;
    ss = pat;
    while (*pat != '"') {
      fragment_len++;
      pat++;
    }
    city = g_strndup(ss, fragment_len);
  }

  if ((pat = g_strstr_len(text, len, JSON_LATITUDE_PATTERN))) {
    pat += strlen(JSON_LATITUDE_PATTERN);
    ss = lat_buf;
    if (*pat == '-')
      *ss++ = *pat++;
    while ((ss < (lat_buf + sizeof(lat_buf))) && (pat < (text + len)) &&
	   (g_ascii_isdigit(*pat) || (*pat == '.')))
      *ss++ = *pat++;
    *ss = '\0';
    ll->lat = g_ascii_strtod(lat_buf, NULL);
  }

  if ((pat = g_strstr_len(text, len, JSON_LONGITUDE_PATTERN))) {
    pat += strlen(JSON_LONGITUDE_PATTERN);
    ss = lon_buf;
    if (*pat == '-')
      *ss++ = *pat++;
    while ((ss < (lon_buf + sizeof(lon_buf))) && (pat < (text + len)) &&
	   (g_ascii_isdigit(*pat) || (*pat == '.')))
      *ss++ = *pat++;
    *ss = '\0';
    ll->lon = g_ascii_strtod(lon_buf, NULL);
  }

  if ( ll->lat != 0.0 && ll->lon != 0.0 ) {
    if ( ll->lat > -90.0 && ll->lat < 90.0 && ll->lon > -180.0 && ll->lon < 180.0 ) {
      // Found a 'sensible' & 'precise' location
      result = 1;
      *name = g_strdup ( _("Locality") ); //Albeit maybe not known by an actual name!
    }
  }
  else {
    // Hopefully city name is unique enough to lookup position on
    // For American places the service may append the State code on the end
    // But if the country code is not appended if could easily get confused
    //  e.g. 'Portsmouth' could be at least
    //   Portsmouth, Hampshire, UK or
    //   Portsmouth, Viginia, USA.

    // Try city name lookup
    if ( city ) {
      g_debug ( "%s: found city %s", __FUNCTION__, city );
      if ( strcmp ( city, "(Unknown city)" ) != 0 ) {
        VikCoord new_center;
        if ( vik_goto_place ( NULL, vvp, city, &new_center ) ) {
          // Got something
          vik_coord_to_latlon ( &new_center, ll );
          result = 2;
          *name = city;
          goto tidy;
        }
      }
    }

    // Try country name lookup
    if ( country ) {
      g_debug ( "%s: found country %s", __FUNCTION__, country );
      if ( strcmp ( country, "(Unknown Country)" ) != 0 ) {
        VikCoord new_center;
        if ( vik_goto_place ( NULL, vvp, country, &new_center ) ) {
          // Finally got something
          vik_coord_to_latlon ( &new_center, ll );
          result = 3;
          *name = country;
          goto tidy;
        }
      }
    }
  }
  
 tidy:
  g_mapped_file_unref ( mf );
  (void)g_remove ( tmpname );
  g_free ( tmpname );
  return result;
}