/* Tower Toppler - Nebulus
 * Copyright (C) 2000-2012  Andreas Röver
 *
 * 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.
 */

#include "txtsys.h"
#include "screen.h"
#include "keyb.h"
#include "menu.h"
#include <stdlib.h>
#include <string.h>

textsystem::textsystem(char *title, menuopt_callback_proc pr)
{
  if (title) {
    this->title = new char[strlen(title)+1];
    strcpy(this->title, title);
  } else this->title = NULL;

  numlines = 0;
  max_length = 0;
  lines = NULL;
  mproc = pr;
  xoffs = yoffs = disp_xoffs = disp_yoffs = 0;
  ystart = (title) ? FONTHEI + 15 : 0;
  shownlines = ((SCREENHEI - ystart) / FONTHEI) + 1;
}

textsystem::~textsystem()
{
  int i;

  if (lines && numlines) {
    for (i = 0; i < numlines; i++)
      if (lines[i])
        delete [] lines[i];
    delete [] lines;
  }
  if (title) delete [] title;
}

void textsystem::addline(char *line)
{
  int olen;

  char **tmp = new char *[numlines+1];
  if (!tmp) return;

  if (lines) {
    memcpy(tmp, lines, sizeof(char *) * numlines);
    delete [] lines;
  }

  if (line && (strlen(line)>0)) {
    tmp[numlines] = new char[strlen(line)+1];
    strcpy(tmp[numlines], line);
  } else tmp[numlines] = NULL;

  lines = tmp;
  numlines++;

  if (line) {
    olen = scr_formattextlength(0,0,line);
    if (olen < 0) olen = 0;
  }
  else olen = 0;

  if (max_length < olen) max_length = olen;
}

void textsystem::run()
{
  bool ende = false;
  SDLKey key = SDLK_UNKNOWN;

  do {
    (void)key_readkey();

    draw();

    key = key_sdlkey();

    switch (key_sdlkey2conv(key, false)) {
    case up_key:
      if (yoffs >= FONTHEI) yoffs -= FONTHEI;
      else yoffs = 0;
      break;
    case down_key:
      if (yoffs + (shownlines*FONTHEI) < (numlines*FONTHEI)) yoffs += FONTHEI;
      else yoffs = (numlines - shownlines+1)*FONTHEI;
      break;
    case break_key:
      ende = true;
      break;
    case left_key:
      if (xoffs >= FONTWID) xoffs -= FONTWID;
      else xoffs = 0;
      break;
    case right_key:
      if (xoffs <= max_length-SCREENWID-FONTWID) xoffs += FONTWID;
      else xoffs = max_length-SCREENWID;
      break;
    default:
      switch (key) {
      case SDLK_PAGEUP:
        if (yoffs >= shownlines*FONTHEI) yoffs -= shownlines*FONTHEI;
        else yoffs = 0;
        break;
      case SDLK_SPACE:
      case SDLK_PAGEDOWN:
        if ((yoffs/FONTHEI) + (shownlines*2) <= numlines)
          yoffs += shownlines*FONTHEI;
        else yoffs = (numlines - shownlines+1)*FONTHEI;
        break;
      case SDLK_HOME:
        yoffs = 0;
        break;
      case SDLK_END:
        yoffs = (numlines - shownlines+1)*FONTHEI;
        break;
      case SDLK_RETURN:
      case SDLK_ESCAPE:
        ende = true;
        break;
      default: break;
      }
    }

  } while (!ende);
}

void
textsystem::draw()
{
  char pointup[2], pointdown[2], pointleft[2], pointright[2];

  pointup[0] = fontptrup;
  pointup[1] = 0;
  pointdown[0] = fontptrdown;
  pointdown[1] = 0;
  pointleft[0] = fontptrleft;
  pointleft[1] = 0;
  pointright[0] = fontptrright;
  pointright[1] = 0;

  if (mproc)
    (*mproc) (NULL);

  if (title)
    scr_writetext_center(5, title);

  if (disp_yoffs < yoffs) {
    disp_yoffs += ((yoffs - disp_yoffs+3) / 4)+1;
    if (disp_yoffs > yoffs) disp_yoffs = yoffs;
  } else if (disp_yoffs > yoffs) {
    disp_yoffs -= ((disp_yoffs - yoffs+3) / 4)+1;
    if (disp_yoffs < yoffs) disp_yoffs = yoffs;
  }

  if (disp_xoffs < xoffs) {
    disp_xoffs += ((xoffs - disp_xoffs) / 4)+1;
    if (disp_xoffs > xoffs) disp_xoffs = xoffs;
  } else if (disp_xoffs > xoffs) {
    disp_xoffs -= ((disp_xoffs - xoffs) / 4)+1;
    if (disp_xoffs < xoffs) disp_xoffs = xoffs;
  }

  scr_setclipping(0, ystart, SCREENWID, SCREENHEI);
  for (int k = 0; k <= shownlines; k++)
    if (k+(disp_yoffs / FONTHEI) < numlines) {
      if (lines[k+(disp_yoffs / FONTHEI)])
        scr_writeformattext(-disp_xoffs,
                            k*FONTHEI + ystart - (disp_yoffs % FONTHEI),
                            lines[k+(disp_yoffs / FONTHEI)]);
    }

  scr_setclipping();

  if (disp_yoffs > 0)
    scr_writetext(SCREENWID-FONTWID, 34, pointup);
  if ((disp_yoffs / FONTHEI) + shownlines < numlines)
    scr_writetext(SCREENWID-FONTWID, SCREENHEI-FONTHEI, pointdown);

  if (disp_xoffs > 0)
    scr_writetext(FONTWID, 5, pointleft);
  if (disp_xoffs < max_length - SCREENWID)
    scr_writetext(SCREENWID-FONTWID, 5, pointright);

  scr_swap();
  dcl_wait();
}