/*
 * Calcurse - text-based organizer
 *
 * Copyright (c) 2004-2012 calcurse Development Team <misc@calcurse.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the
 *        following disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the
 *        following disclaimer in the documentation and/or other
 *        materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Send your feedback or comments to : misc@calcurse.org
 * Calcurse home page : http://calcurse.org
 *
 */

#include <stdlib.h>
#include <string.h>
#include <math.h>

#include "calcurse.h"

/* Variables to handle calcurse windows. */
struct window win[NBWINS];

/* User-configurable side bar width. */
static unsigned sbarwidth_perc;

static enum win slctd_win;
static int layout;

/*
 * The screen_mutex mutex and wins_refresh(), wins_wrefresh(), wins_doupdate()
 * functions are used to prevent concurrent updates of the screen.
 * It was observed that the display could get screwed up when mulitple threads
 * tried to refresh the screen at the same time.
 *
 * Note (2010-03-21):
 * Since recent versions of ncurses (5.7), rudimentary support for threads are
 * available (use_screen(), use_window() for instance - see curs_threads(3)),
 * but to remain compatible with earlier versions, it was chosen to rely on a
 * screen-level mutex instead.
 */
static pthread_mutex_t screen_mutex = PTHREAD_MUTEX_INITIALIZER;

static unsigned screen_acquire(void)
{
  if (pthread_mutex_lock(&screen_mutex) != 0)
    return 0;
  else
    return 1;
}

static void screen_release(void)
{
  pthread_mutex_unlock(&screen_mutex);
}

int wins_refresh(void)
{
  int rc;

  if (!screen_acquire())
    return ERR;
  rc = refresh();
  screen_release();

  return rc;
}

int wins_wrefresh(WINDOW * win)
{
  int rc;

  if (!win || !screen_acquire())
    return ERR;
  rc = wrefresh(win);
  screen_release();

  return rc;
}

int wins_doupdate(void)
{
  int rc;

  if (!screen_acquire())
    return ERR;
  rc = doupdate();
  screen_release();

  return rc;
}

/* Get the current layout. */
int wins_layout(void)
{
  return layout;
}

/* Set the current layout. */
void wins_set_layout(int nb)
{
  layout = nb;
}

/* Get the current side bar width. */
unsigned wins_sbar_width(void)
{
  if (sbarwidth_perc > SBARMAXWIDTHPERC)
    return col * SBARMAXWIDTHPERC / 100;
  else {
    unsigned sbarwidth = (unsigned)(col * sbarwidth_perc / 100);
    return (sbarwidth < SBARMINWIDTH) ? SBARMINWIDTH : sbarwidth;
  }
}

/*
 * Return the side bar width in percentage of the total number of columns
 * available in calcurse's screen.
 */
unsigned wins_sbar_wperc(void)
{
  return sbarwidth_perc > SBARMAXWIDTHPERC ? SBARMAXWIDTHPERC : sbarwidth_perc;
}

/*
 * Set side bar width (unit: number of characters) given a width in percentage
 * of calcurse's screen total width.
 * The side bar could not have a width representing more than 50% of the screen,
 * and could not be less than SBARMINWIDTH characters.
 */
void wins_set_sbar_width(unsigned perc)
{
  sbarwidth_perc = perc;
}

/* Change the width of the side bar within acceptable boundaries. */
void wins_sbar_winc(void)
{
  if (sbarwidth_perc < SBARMAXWIDTHPERC)
    sbarwidth_perc++;
}

void wins_sbar_wdec(void)
{
  if (sbarwidth_perc > 0)
    sbarwidth_perc--;
}

/* Initialize the selected window in calcurse's interface. */
void wins_slctd_init(void)
{
  wins_slctd_set(CAL);
}

/* Returns an enum which corresponds to the window which is selected. */
enum win wins_slctd(void)
{
  return slctd_win;
}

/* Sets the selected window. */
void wins_slctd_set(enum win window)
{
  slctd_win = window;
}

/* TAB key was hit in the interface, need to select next window. */
void wins_slctd_next(void)
{
  if (slctd_win == TOD)
    slctd_win = CAL;
  else
    slctd_win++;
}

static void wins_init_panels(void)
{
  win[CAL].p = newwin(CALHEIGHT, wins_sbar_width(), win[CAL].y, win[CAL].x);
  wins_show(win[CAL].p, _("Calendar"));

  win[APP].p = newwin(win[APP].h, win[APP].w, win[APP].y, win[APP].x);
  wins_show(win[APP].p, _("Appointments"));
  apad.width = win[APP].w - 3;
  apad.ptrwin = newpad(apad.length, apad.width);

  win[TOD].p = newwin(win[TOD].h, win[TOD].w, win[TOD].y, win[TOD].x);
  wins_show(win[TOD].p, _("ToDo"));

  /* Enable function keys (i.e. arrow keys) in those windows */
  keypad(win[CAL].p, TRUE);
  keypad(win[APP].p, TRUE);
  keypad(win[TOD].p, TRUE);
}

/* Create all the windows. */
void wins_init(void)
{
  wins_init_panels();
  win[STA].p = newwin(win[STA].h, win[STA].w, win[STA].y, win[STA].x);

  keypad(win[STA].p, TRUE);

  /* Notify that the curses mode is now launched. */
  ui_mode = UI_CURSES;
}

/*
 * Create a new window and its associated pad, which is used to make the
 * scrolling faster.
 */
void wins_scrollwin_init(struct scrollwin *sw)
{
  EXIT_IF(sw == NULL, "null pointer");
  sw->win.p = newwin(sw->win.h, sw->win.w, sw->win.y, sw->win.x);
  sw->pad.p = newpad(sw->pad.h, sw->pad.w);
  sw->first_visible_line = 0;
  sw->total_lines = 0;
}

/* Free an already created scrollwin. */
void wins_scrollwin_delete(struct scrollwin *sw)
{
  EXIT_IF(sw == NULL, "null pointer");
  delwin(sw->win.p);
  delwin(sw->pad.p);
}

/* Display a scrolling window. */
void wins_scrollwin_display(struct scrollwin *sw)
{
  const int visible_lines = sw->win.h - sw->pad.y - 1;

  if (sw->total_lines > visible_lines) {
    float ratio = ((float)visible_lines) / ((float)sw->total_lines);
    int sbar_length = (int)(ratio * visible_lines);
    int highend = (int)(ratio * sw->first_visible_line);
    int sbar_top = highend + sw->pad.y + 1;

    if ((sbar_top + sbar_length) > sw->win.h - 1)
      sbar_length = sw->win.h - sbar_top;
    draw_scrollbar(sw->win.p, sbar_top, sw->win.w + sw->win.x - 2,
                   sbar_length, sw->pad.y + 1, sw->win.h - 1, 1);
  }
  wmove(win[STA].p, 0, 0);
  wnoutrefresh(sw->win.p);
  pnoutrefresh(sw->pad.p, sw->first_visible_line, 0, sw->pad.y, sw->pad.x,
               sw->win.h - sw->pad.y + 1, sw->win.w - sw->win.x);
  wins_doupdate();
}

void wins_scrollwin_up(struct scrollwin *sw, int amount)
{
  if (sw->first_visible_line > 0)
    sw->first_visible_line -= amount;
}

void wins_scrollwin_down(struct scrollwin *sw, int amount)
{
  if (sw->total_lines > (sw->first_visible_line + sw->win.h - sw->pad.y - 1))
    sw->first_visible_line += amount;
}

void wins_reinit_panels(void)
{
  delwin(win[CAL].p);
  delwin(win[APP].p);
  delwin(apad.ptrwin);
  delwin(win[TOD].p);
  wins_get_config();
  wins_init_panels();
}

/*
 * Delete the existing windows and recreate them with their new
 * size and placement.
 */
void wins_reinit(void)
{
  delwin(win[CAL].p);
  delwin(win[APP].p);
  delwin(apad.ptrwin);
  delwin(win[TOD].p);
  delwin(win[STA].p);
  wins_get_config();
  wins_init();
  if (notify_bar())
    notify_reinit_bar();
}

/* Show the window with a border and a label. */
void wins_show(WINDOW * win, const char *label)
{
  int width = getmaxx(win);

  box(win, 0, 0);
  mvwaddch(win, 2, 0, ACS_LTEE);
  mvwhline(win, 2, 1, ACS_HLINE, width - 2);
  mvwaddch(win, 2, width - 1, ACS_RTEE);

  print_in_middle(win, 1, 0, width, label);
}

/*
 * Get the screen size and recalculate the windows configurations.
 */
void wins_get_config(void)
{
  /* Get the screen configuration */
  getmaxyx(stdscr, row, col);

  /* fixed values for status, notification bars and calendar */
  win[STA].h = STATUSHEIGHT;
  win[STA].w = col;
  win[STA].y = row - win[STA].h;
  win[STA].x = 0;

  if (notify_bar()) {
    win[NOT].h = 1;
    win[NOT].w = col;
    win[NOT].y = win[STA].y - 1;
    win[NOT].x = 0;
  } else {
    win[NOT].h = 0;
    win[NOT].w = 0;
    win[NOT].y = 0;
    win[NOT].x = 0;
  }

  win[CAL].w = wins_sbar_width();
  win[CAL].h = CALHEIGHT;

  if (layout <= 4) {            /* APPOINTMENT is the biggest panel */
    win[APP].w = col - win[CAL].w;
    win[APP].h = row - (win[STA].h + win[NOT].h);
    win[TOD].w = win[CAL].w;
    win[TOD].h = row - (win[CAL].h + win[STA].h + win[NOT].h);
  } else {                      /* TODO is the biggest panel */
    win[TOD].w = col - win[CAL].w;
    win[TOD].h = row - (win[STA].h + win[NOT].h);
    win[APP].w = win[CAL].w;
    win[APP].h = row - (win[CAL].h + win[STA].h + win[NOT].h);
  }

  /* defining the layout */
  switch (layout) {
  case 1:
    win[APP].y = 0;
    win[APP].x = 0;
    win[CAL].y = 0;
    win[TOD].x = win[APP].w;
    win[TOD].y = win[CAL].h;
    win[CAL].x = win[APP].w;
    break;
  case 2:
    win[APP].y = 0;
    win[APP].x = 0;
    win[TOD].y = 0;
    win[TOD].x = win[APP].w;
    win[CAL].x = win[APP].w;
    win[CAL].y = win[TOD].h;
    break;
  case 3:
    win[APP].y = 0;
    win[TOD].x = 0;
    win[CAL].x = 0;
    win[CAL].y = 0;
    win[APP].x = win[CAL].w;
    win[TOD].y = win[CAL].h;
    break;
  case 4:
    win[APP].y = 0;
    win[TOD].x = 0;
    win[TOD].y = 0;
    win[CAL].x = 0;
    win[APP].x = win[CAL].w;
    win[CAL].y = win[TOD].h;
    break;
  case 5:
    win[TOD].y = 0;
    win[TOD].x = 0;
    win[CAL].y = 0;
    win[APP].y = win[CAL].h;
    win[APP].x = win[TOD].w;
    win[CAL].x = win[TOD].w;
    break;
  case 6:
    win[TOD].y = 0;
    win[TOD].x = 0;
    win[APP].y = 0;
    win[APP].x = win[TOD].w;
    win[CAL].x = win[TOD].w;
    win[CAL].y = win[APP].h;
    break;
  case 7:
    win[TOD].y = 0;
    win[APP].x = 0;
    win[CAL].x = 0;
    win[CAL].y = 0;
    win[TOD].x = win[CAL].w;
    win[APP].y = win[CAL].h;
    break;
  case 8:
    win[TOD].y = 0;
    win[APP].x = 0;
    win[CAL].x = 0;
    win[APP].y = 0;
    win[TOD].x = win[CAL].w;
    win[CAL].y = win[APP].h;
    break;
  }
}

/* draw panel border in color */
static void border_color(WINDOW * window)
{
  int color_attr = A_BOLD;
  int no_color_attr = A_BOLD;

  if (colorize) {
    wattron(window, color_attr | COLOR_PAIR(COLR_CUSTOM));
    box(window, 0, 0);
  } else {
    wattron(window, no_color_attr);
    box(window, 0, 0);
  }
  if (colorize) {
    wattroff(window, color_attr | COLOR_PAIR(COLR_CUSTOM));
  } else {
    wattroff(window, no_color_attr);
  }
  wnoutrefresh(window);
}

/* draw panel border without any color */
static void border_nocolor(WINDOW * window)
{
  int color_attr = A_BOLD;
  int no_color_attr = A_DIM;

  if (colorize) {
    wattron(window, color_attr | COLOR_PAIR(COLR_DEFAULT));
  } else {
    wattron(window, no_color_attr);
  }
  box(window, 0, 0);
  if (colorize) {
    wattroff(window, color_attr | COLOR_PAIR(COLR_DEFAULT));
  } else {
    wattroff(window, no_color_attr);
  }
  wnoutrefresh(window);
}

void wins_update_border(int flags)
{
  if (flags & FLAG_CAL) {
    if (slctd_win == CAL)
      border_color(win[CAL].p);
    else
      border_nocolor(win[CAL].p);
  }
  if (flags & FLAG_APP) {
    if (slctd_win == APP)
      border_color(win[APP].p);
    else
      border_nocolor(win[APP].p);
  }
  if (flags & FLAG_TOD) {
    if (slctd_win == TOD)
      border_color(win[TOD].p);
    else
      border_nocolor(win[TOD].p);
  }
}

void wins_update_panels(int flags)
{
  if (flags & FLAG_APP)
    apoint_update_panel(slctd_win);
  if (flags & FLAG_TOD)
    todo_update_panel(slctd_win);
  if (flags & FLAG_CAL)
    calendar_update_panel(&win[CAL]);
}

/*
 * Update all of the three windows and put a border around the
 * selected window.
 */
void wins_update(int flags)
{
  wins_update_border(flags);
  wins_update_panels(flags);
  if (flags & FLAG_STA)
    wins_status_bar();
  if ((flags & FLAG_NOT) && notify_bar())
    notify_update_bar();
  wmove(win[STA].p, 0, 0);
  wins_doupdate();
}

/* Reset the screen, needed when resizing terminal for example. */
void wins_reset(void)
{
  endwin();
  wins_refresh();
  curs_set(0);
  wins_reinit();
  wins_update(FLAG_ALL);
}

/* Prepare windows for the execution of an external command. */
void wins_prepare_external(void)
{
  if (notify_bar())
    notify_stop_main_thread();
  def_prog_mode();
  ui_mode = UI_CMDLINE;
  clear();
  wins_refresh();
  endwin();
}

/* Restore windows when returning from an external command. */
void wins_unprepare_external(void)
{
  reset_prog_mode();
  clearok(curscr, TRUE);
  curs_set(0);
  ui_mode = UI_CURSES;
  wins_refresh();
  if (notify_bar())
    notify_start_main_thread();
}

/*
 * While inside interactive mode, launch the external command cmd on the given
 * file.
 */
void wins_launch_external(const char *file, const char *cmd)
{
  const char *arg[] = { cmd, file, NULL };
  int pid;

  wins_prepare_external();
  if ((pid = shell_exec(NULL, NULL, *arg, arg)))
    child_wait(NULL, NULL, pid);
  wins_unprepare_external();
}

#define NB_CAL_CMDS    27       /* number of commands while in cal view */
#define NB_APP_CMDS    32       /* same thing while in appointment view */
#define NB_TOD_CMDS    31       /* same thing while in todo view */

static unsigned status_page;

/*
 * Draws the status bar.
 * To add a keybinding, insert a new binding_t item, add it in the *binding
 * table, and update the NB_CAL_CMDS, NB_APP_CMDS or NB_TOD_CMDS defines,
 * depending on which panel the added keybind is assigned to.
 */
void wins_status_bar(void)
{
  struct binding help = { _("Help"), KEY_GENERIC_HELP };
  struct binding quit = { _("Quit"), KEY_GENERIC_QUIT };
  struct binding save = { _("Save"), KEY_GENERIC_SAVE };
  struct binding cut = { _("Cut"), KEY_GENERIC_CUT };
  struct binding paste = { _("Paste"), KEY_GENERIC_PASTE };
  struct binding chgvu = { _("Chg Win"), KEY_GENERIC_CHANGE_VIEW };
  struct binding import = { _("Import"), KEY_GENERIC_IMPORT };
  struct binding export = { _("Export"), KEY_GENERIC_EXPORT };
  struct binding togo = { _("Go to"), KEY_GENERIC_GOTO };
  struct binding conf = { _("Config"), KEY_GENERIC_CONFIG_MENU };
  struct binding draw = { _("Redraw"), KEY_GENERIC_REDRAW };
  struct binding appt = { _("Add Appt"), KEY_GENERIC_ADD_APPT };
  struct binding todo = { _("Add Todo"), KEY_GENERIC_ADD_TODO };
  struct binding gnday = { _("+1 Day"), KEY_GENERIC_NEXT_DAY };
  struct binding gpday = { _("-1 Day"), KEY_GENERIC_PREV_DAY };
  struct binding gnweek = { _("+1 Week"), KEY_GENERIC_NEXT_WEEK };
  struct binding gpweek = { _("-1 Week"), KEY_GENERIC_PREV_WEEK };
  struct binding today = { _("Today"), KEY_GENERIC_GOTO_TODAY };
  struct binding nview = { _("Nxt View"), KEY_GENERIC_SCROLL_DOWN };
  struct binding pview = { _("Prv View"), KEY_GENERIC_SCROLL_UP };
  struct binding up = { _("Up"), KEY_MOVE_UP };
  struct binding down = { _("Down"), KEY_MOVE_DOWN };
  struct binding left = { _("Left"), KEY_MOVE_LEFT };
  struct binding right = { _("Right"), KEY_MOVE_RIGHT };
  struct binding weekb = { _("beg Week"), KEY_START_OF_WEEK };
  struct binding weeke = { _("end Week"), KEY_END_OF_WEEK };
  struct binding add = { _("Add Item"), KEY_ADD_ITEM };
  struct binding del = { _("Del Item"), KEY_DEL_ITEM };
  struct binding edit = { _("Edit Itm"), KEY_EDIT_ITEM };
  struct binding view = { _("View"), KEY_VIEW_ITEM };
  struct binding pipe = { _("Pipe"), KEY_PIPE_ITEM };
  struct binding flag = { _("Flag Itm"), KEY_FLAG_ITEM };
  struct binding rept = { _("Repeat"), KEY_REPEAT_ITEM };
  struct binding enote = { _("EditNote"), KEY_EDIT_NOTE };
  struct binding vnote = { _("ViewNote"), KEY_VIEW_NOTE };
  struct binding rprio = { _("Prio.+"), KEY_RAISE_PRIORITY };
  struct binding lprio = { _("Prio.-"), KEY_LOWER_PRIORITY };
  struct binding othr = { _("OtherCmd"), KEY_GENERIC_OTHER_CMD };

  struct binding *bindings_cal[] = {
    &help, &quit, &save, &chgvu, &nview, &pview, &up, &down, &left, &right,
    &togo, &import, &export, &weekb, &weeke, &appt, &todo, &gnday, &gpday,
    &gnweek, &gpweek, &draw, &today, &conf
  };

  struct binding *bindings_apoint[] = {
    &help, &quit, &save, &chgvu, &import, &export, &add, &del, &edit, &view,
    &pipe, &draw, &rept, &flag, &enote, &vnote, &up, &down, &gnday, &gpday,
    &gnweek, &gpweek, &togo, &today, &conf, &appt, &todo, &cut, &paste
  };

  struct binding *bindings_todo[] = {
    &help, &quit, &save, &chgvu, &import, &export, &add, &del, &edit, &view,
    &pipe, &flag, &rprio, &lprio, &enote, &vnote, &up, &down, &gnday, &gpday,
    &gnweek, &gpweek, &togo, &today, &conf, &appt, &todo, &draw
  };

  enum win active_panel = wins_slctd();

  struct binding **bindings;
  int bindings_size;

  switch (active_panel) {
  case CAL:
    bindings = bindings_cal;
    bindings_size = sizeof(bindings_cal) / sizeof(bindings_cal[0]);
    break;
  case APP:
    bindings = bindings_apoint;
    bindings_size = sizeof(bindings_apoint) / sizeof(bindings_apoint[0]);
    break;
  case TOD:
    bindings = bindings_todo;
    bindings_size = sizeof(bindings_todo) / sizeof(bindings_todo[0]);
    break;
  default:
    EXIT(_("unknown panel"));
    /* NOTREACHED */
  }

  keys_display_bindings_bar(win[STA].p, bindings, bindings_size,
                            (KEYS_CMDS_PER_LINE * 2 - 1) * (status_page - 1),
                            KEYS_CMDS_PER_LINE * 2, &othr);
}

/* Erase status bar. */
void wins_erase_status_bar(void)
{
  erase_window_part(win[STA].p, 0, 0, col, STATUSHEIGHT);
}

/* Update the status bar page number to display other commands. */
void wins_other_status_page(int panel)
{
  int nb_item, max_page;

  switch (panel) {
  case CAL:
    nb_item = NB_CAL_CMDS;
    break;
  case APP:
    nb_item = NB_APP_CMDS;
    break;
  case TOD:
    nb_item = NB_TOD_CMDS;
    break;
  default:
    EXIT(_("unknown panel"));
    /* NOTREACHED */
  }
  max_page = nb_item / (KEYS_CMDS_PER_LINE * 2 - 1) + 1;
  status_page = (status_page % max_page) + 1;
}

/* Reset the status bar page. */
void wins_reset_status_page(void)
{
  status_page = 1;
}

#undef NB_CAL_CMDS
#undef NB_APP_CMDS
#undef NB_TOD_CMDS