#include "game.h"
#include <time.h>
#include <stdlib.h>
#include <string.h>

#define MAX_RAND_TRIES_PER_WORD 10
#define EMPTY_CHAR 0

typedef enum { HORIZONTAL, VERTICAL } Direction;

static int canPlaceWord(char salad[MAX_SEARCH_FIELD_LEN][MAX_SEARCH_FIELD_LEN], const char *word, unsigned int wordLen, unsigned int row, unsigned int col, Direction dir){
   for(unsigned int k = 0; k < wordLen; k++){
      //iteriert durch das 2D Grid je nach Richtung
      unsigned int r = (dir == VERTICAL) ? row + k : row;
      unsigned int c = (dir == HORIZONTAL) ? col + k: col;

      // Falls das Feld leer ist oder der gleiche Buchstabe drinnen ist.
      if(salad[r][c] != EMPTY_CHAR && salad[r][c] != word[k])
         return 0;
   }
   return 1;
}

static void placeWord(char salad[MAX_SEARCH_FIELD_LEN][MAX_SEARCH_FIELD_LEN], const char *word, unsigned int wordLen, unsigned int row, unsigned int col, Direction dir){
   for(unsigned int k = 0; k < wordLen; k++){
      //iteriert durch das 2D Grid je nach Richtung
      unsigned int r = (dir == VERTICAL) ? row + k : row;
      unsigned int c = (dir == HORIZONTAL) ? col + k : col;

      //schreibt das wort
      salad[r][c] = word[k];
   }
}

static int tryPlaceWord(char salad[MAX_SEARCH_FIELD_LEN][MAX_SEARCH_FIELD_LEN], unsigned int searchFieldLen, const char *word){
   unsigned int wordLen = strlen(word);

   if(wordLen == 0 || wordLen > searchFieldLen) // sichergehen, dass es ein valides Wort ist
        return 0;

   for(int tries = 0; tries < MAX_RAND_TRIES_PER_WORD; tries++){
      Direction dir = (rand() % 2 == 0 ) ? HORIZONTAL : VERTICAL;
      unsigned int searchSize;
      unsigned int row, col;

      searchSize = searchFieldLen - wordLen;

      if(dir == HORIZONTAL)
      {
         row = rand() % searchFieldLen; // Macht das sinn? Wenn 412 % bspw. 8 = 4
         col = rand() % (searchSize + 1); // Bspw. 154 % ((20 - 6) +1) = 14
      }
      else
      {
         row = rand() % (searchSize + 1);
         col = rand() % searchFieldLen;
      }

      if(canPlaceWord(salad, word, wordLen, row, col, dir)) // schaut nach ob es platzieren kann
      {
         placeWord(salad, word, wordLen, row, col, dir); // platziert das wort, falls ja
         return 1;
      }
   }
   return 0;
}

// füllt restliche Leere Felder mit random Buchstaben.
static void fillEmpty(char salad[MAX_SEARCH_FIELD_LEN][MAX_SEARCH_FIELD_LEN], unsigned int searchFieldLen){
   for(unsigned int r = 0; r < searchFieldLen; r++){
      for(unsigned int c = 0; c < searchFieldLen; c++){
         if(salad[r][c] == EMPTY_CHAR){
            salad[r][c] = 'A' + (rand() % 26); // start mit A also 0100 0001/Dec(65)und addiert dann 0-25 um bis Z abzudecken.
         }
      }
   }
}


int createWordSalad(char salad[MAX_SEARCH_FIELD_LEN][MAX_SEARCH_FIELD_LEN], unsigned int searchFieldLen, const char words[][MAX_WORD_LEN], unsigned int wordCount)
{
   static int isSeeded = 0;
   int placedWords = 0;

   if (searchFieldLen > MAX_SEARCH_FIELD_LEN){
      return 0;
   }
   // stellt sich wieder haben Random Seed
   if(!isSeeded){
      srand((unsigned int)time(NULL));
      isSeeded = 1;
   }
   //setzt alle einträge im array auf 0
   for(unsigned int r = 0; r < searchFieldLen; r++){
      for(unsigned int c = 0; c < searchFieldLen; c++){
            salad[r][c] = EMPTY_CHAR;
      }
   }

   // Loop für alle Wörter
   for(unsigned int i = 0; i < wordCount; i++){
      if(tryPlaceWord(salad, searchFieldLen, words[i])){
         placedWords++;
      }
   }
   fillEmpty(salad, searchFieldLen);

   return placedWords;
}