#include "mkhiblib.h"

/**
 * Draw a menu
 * 
 * @param hmenu the menu to draw
 * @param screen the scren to draw in
 */
void hl_drawMenu(h_Menu * hmenu, h_ScreenMem screen) {

  short j;
  short height_text = hmenu->font->underline + hmenu->font->upperline + (hmenu->font->underline == 0);
  short y = hmenu->pos_y-height_text;
  short height;
  short pos;
  short nb = 0;
  short x;
  short x_start;
  
  hl_fillFrame(hmenu->pos_x, hmenu->pos_y, hmenu->pos_x + hmenu->width, hmenu->pos_y + height_text * hmenu->nb_draw - 1, HGRAPHMODE_WHITE, screen);

  if (hmenu->level_tab != NULL) {
    for (j = 0; j < hmenu->nb; j++) {
      if (hmenu->level_tab[j].draw) {
        nb++;
      }
    }
  } else {
    nb = hmenu->nb;
  }    
  
  x = hmenu->pos_x;
  
  if (hmenu->draw_scrollbar) {
    if (nb > hmenu->nb_draw) {
      height = (height_text * hmenu->nb_draw * hmenu->nb_draw) / nb - 1;
    } else {
      height = height_text * hmenu->nb_draw - 1;
    }
    pos = (height_text * hmenu->nb_draw * hmenu->top) / nb;
    if (height < 1) {
      height = 1;
    }
    hl_drawLineVert(x, hmenu->pos_y + 1, hmenu->pos_y + hmenu->nb_draw * height_text - 2, HGRAPHMODE_BLACK, screen);
    hl_drawLineVert(x + 3, hmenu->pos_y + 1, hmenu->pos_y + hmenu->nb_draw * height_text - 2, HGRAPHMODE_BLACK, screen);
    hl_drawLineHoriz(x + 1, x + 2, hmenu->pos_y, HGRAPHMODE_BLACK, screen);
    hl_drawLineHoriz(x + 1, x + 2, hmenu->pos_y + hmenu->nb_draw * height_text - 1, HGRAPHMODE_BLACK, screen);
  
    hl_drawLineVert(x + 1, pos + hmenu->pos_y, pos + height + hmenu->pos_y, HGRAPHMODE_BLACK, screen);
    hl_drawLineVert(x + 2, pos + hmenu->pos_y, pos + height + hmenu->pos_y, HGRAPHMODE_BLACK, screen);
    x += 7;
  }
  
  j = hmenu->top;
  nb = 0;
  x_start = x;
  while (j < hmenu->nb && nb < hmenu->nb_draw) {
    x = x_start;
    if (hmenu->level_tab != NULL && hmenu->level_tab[j].draw) {
      x += 6 * hmenu->level_tab[j].level;
    }
    if (hmenu->level_tab == NULL || hmenu->level_tab[j].draw) {
      if (hmenu->fct_draw != NULL) {
        hmenu->fct_draw(j, x + 5, y += height_text, hmenu, screen);
      } else {
        if (hmenu->size_item != 0) {
          hl_drawStr(hmenu->font, x + 5, y += height_text, hmenu->tab + j * hmenu->size_item, FALSE, FALSE, screen);
        } else {
          hl_drawStr(hmenu->font, x + 5, y += height_text, ((unsigned char * * )hmenu->tab)[j], FALSE, FALSE, screen);
        }
      }
      if (hmenu->no_choice == j) {
        hl_drawChar(hmenu->font, x, y, (hmenu->move ? 127 : 18), FALSE, FALSE, screen);
      }
      nb++;
    }
    j++;
  }
  
}


/**
 * Get the nth next item from a position
 * 
 * @param pos the current position
 * @param n the number of item to skip
 * @param hmenu the menu
 *
 * @return the number of the nth next item
 */
short hgetnNext(short pos, short n, h_Menu * hmenu) {
  short last_draw = pos;
  
  if (pos == hmenu->nb - 1)
    return pos;
  
  do {
    pos++;
    if (hmenu->level_tab == NULL || hmenu->level_tab[pos].draw) {
      n--;
      last_draw = pos;
    }
  } while (n > 0 && pos != hmenu->nb - 1);
  
  return last_draw;
}

/**
 * Get the nth previous item from a position
 * 
 * @param pos the current position
 * @param n the number of item to skip
 * @param hmenu the menu
 *
 * @return the number of the nth previous item
 */
short hgetnPrev(short pos, short n, h_Menu * hmenu) {
  short last_draw = pos;
  
  if (pos == 0)
    return pos;
  
  do {
    pos--;
    if (hmenu->level_tab == NULL || hmenu->level_tab[pos].draw) {
      n--;
      last_draw = pos;
    }
  } while (n > 0 && pos > 0);
  
  return last_draw;
}



/**
 * Get the next item with the same level
 * 
 * @param pos the current position
 * @param hmenu the menu
 *
 * @return the position of the next item
 */
short hgetNextHierachic(short pos, h_Menu * hmenu) {
  
  short level = hmenu->level_tab[pos].level;
  
  do {
    pos++;
  } while (pos != hmenu->nb && hmenu->level_tab[pos].level > level);
  
  return pos;
}


/**
 * Draws the sublevel of an item
 * 
 * @param pos the current position
 * @param hmenu the menu
 *
 * @return TODO doc
 */
short hdrawSubLevel(short pos, h_Menu * hmenu) {
  short level = hmenu->level_tab[pos].level;
  
  pos++;
  
  while (pos != hmenu->nb && hmenu->level_tab[pos].level > level) {
    hmenu->level_tab[pos].draw = 1;
    if (!hmenu->level_tab[pos].hide) {
      pos = hdrawSubLevel(pos, hmenu);
    } else {
      pos = hgetNextHierachic(pos, hmenu);
    }
  }
  
  return pos;
}


/**
 * TODO doc
 * 
 * @param hmenu the menu
 * @param choice the current choosen item
 */
void hmoveItem(void * tab, short src, short dest, short size_item) {
  unsigned char buffer[size_item];
  
  signed short sens=( (dest > src) ? 1 : -1 );
  
  memcpy(buffer, tab + src * size_item, size_item);
  
  while (src != dest) {
    memcpy(tab + src * size_item, tab + (src + sens) * size_item, size_item);
    src += sens;
  }
  
  memcpy(tab + dest * size_item, buffer, size_item);
}


/**
 * TODO doc
 * 
 * @param hmenu the menu
 * @param choice the current choosen item
 */
void hmoveItemDown(h_Menu * hmenu, short choice) {
  if (hmenu->move) {
    if (choice == 0) {
      choice = 1;
    }
    hmoveItem(hmenu->tab, hmenu->no_choice, choice, hmenu->size_item);
    if (hmenu->level_tab != NULL) {
      hmoveItem(hmenu->level_tab, hmenu->no_choice, choice, sizeof(h_MenuLevel));
    }
  }
  hmenu->no_choice = choice;
}

/**
 * TODO doc
 * 
 * @param hmenu the menu
 * @param choice the current choosen item
 */
void hmoveItemUp(h_Menu * hmenu, short choice) {
  if (hmenu->move) {
    if (choice == 0) {
      if (hmenu->nb <= hmenu->nb_draw) {
        hmenu->top = 0;
      } else {
        hmenu->top = hmenu->nb - hmenu->nb_draw;
      }
      choice = hmenu->nb - 1;
    }
    hmoveItem(hmenu->tab, hmenu->no_choice, choice, hmenu->size_item);
    if (hmenu->level_tab != NULL) {
      hmoveItem(hmenu->level_tab, hmenu->no_choice, choice, sizeof(h_MenuLevel));
    }
  }
  hmenu->no_choice = choice;
}

/**
 * Go to the bottom
 * 
 * @param hmenu the menu
 */
void hl_goMenuBottom(h_Menu * hmenu) {
  short choice = hgetnPrev(hmenu->nb, 1, hmenu); //get last
  hmenu->top = hgetnPrev(hmenu->nb, hmenu->nb_draw, hmenu); //back of one page
  hmoveItemDown(hmenu, choice);
}

/**
 * Go one page down
 * 
 * @param hmenu the menu
 */
void hl_goMenuPageDown(h_Menu * hmenu) {
  hmenu->top = hgetnNext(hmenu->top, hmenu->nb_draw, hmenu); //go one page down from top
  short choice = hgetnNext(hmenu->no_choice, hmenu->nb_draw, hmenu); //go one page down from choice
  short no_temp = hgetnPrev(hmenu->nb, hmenu->nb_draw, hmenu); //go one page back from end
  if (no_temp < hmenu->top) { //overflow
    hmenu->top = no_temp;
  }
  hmoveItemDown(hmenu, choice);
}

/**
 * Go to the next shown item
 * 
 * @param hmenu the menu
 */
void hl_goMenuDown(h_Menu * hmenu) {
  short choice = hgetnNext(hmenu->no_choice, 1, hmenu); //go one down from no_choice
  if (choice == hmenu->no_choice) { //we are at the end
    choice = hgetnNext(-1,1,hmenu); //get the first
    hmenu->top = choice;
  } else {
    short no_temp = hgetnNext(choice, 1, hmenu);  //get the next from choice
    no_temp = hgetnPrev(no_temp, hmenu->nb_draw - 1, hmenu); //go back one page from no_temp : search the top
    if (no_temp > hmenu->top) {//overflow
      hmenu->top = no_temp;
    }
    no_temp = hgetnPrev(hmenu->nb, 1, hmenu); //maximum top
    if (no_temp < hmenu->top) {//overflow
      hmenu->top = no_temp;
    }
  }
  hmoveItemDown(hmenu, choice);
}


/**
 * Go to the top
 * 
 * @param hmenu the menu
 */
void hl_goMenuTop(h_Menu * hmenu) {
  hmenu->top = hgetnNext(-1, 1, hmenu);
  hmenu->no_choice = hmenu->top;
}

/**
 * Go one page up
 * 
 * @param hmenu the menu
 */
void hl_goMenuPageUp(h_Menu * hmenu) {
  hmenu->top = hgetnPrev(hmenu->top, hmenu->nb_draw, hmenu); //get one page back from top
  short choice = hgetnPrev(hmenu->no_choice, hmenu->nb_draw, hmenu); //get one page back from choice
  hmoveItemUp(hmenu, choice);
}

/**
 * Go to the previous shown item
 * 
 * @param hmenu the menu
 */
void hl_goMenuUp(h_Menu * hmenu) {
  short choice = hgetnPrev(hmenu->no_choice, 1, hmenu);  //go back one from no_choice
  if (choice == hmenu->no_choice) {  //we are at the first
    choice = hgetnPrev(hmenu->nb, 1, hmenu);  //go to the end
    hmenu->top = hgetnPrev(hmenu->nb, hmenu->nb_draw, hmenu); //go back one page from end
  } else {
    if (choice <= hmenu->top) { //overflow
      hmenu->top = hgetnPrev(hmenu->top, 1, hmenu); //go back one from top
    }
  }
  hmoveItemUp(hmenu, choice);
}

/**
 * Draws the sublevels of the active item
 * 
 * @param hmenu the menu
 */
void hl_goSubMenu(h_Menu * hmenu) {
  hmenu->level_tab[hmenu->no_choice].hide = 0;  //hide the item
  hdrawSubLevel(hmenu->no_choice, hmenu);
}

/**
 * Hide the item and its siblings and go to its parent
 * 
 * @param hmenu the menu
 */
void hl_goUpperMenu(h_Menu * hmenu) {
  hmenu->level_tab[hmenu->no_choice].hide = 1;  //hide the item
  short no_temp = hmenu->no_choice + 1;
  //go down and don't draw any item with a bigger level
  while (no_temp < hmenu->nb && hmenu->level_tab[hmenu->no_choice].level < hmenu->level_tab[no_temp].level) {
    hmenu->level_tab[no_temp++].draw=0;  //hide the item
  }
  //calcul of the last top
  no_temp = hgetnPrev(hmenu->nb, hmenu->nb_draw, hmenu);
  if (no_temp < hmenu->top) {
    hmenu->top = no_temp;
  }
}