#include <stdio.h>
#include <stdlib.h>
#include <SDL/SDL.h>
#include <string.h>
#define TAILLEMAX 2000
enum {BAS, DROITE, HAUT, GAUCHE};

void initialiseSerpent(SDL_Rect positionSerpent[], SDL_Surface *serpent, SDL_Surface *ecran, int taille);
void blitteSerpent(SDL_Surface *serpent, SDL_Surface *ecran, SDL_Rect positionSerpent[], int taille, int direction, SDL_Surface *tete[]);
void decalePositions(SDL_Rect positionSerpent[], int taille);
void avanceSerpent(SDL_Surface *serpent, SDL_Rect positionSerpent[], int direction);
void perdu(SDL_Surface *boum, SDL_Surface *ecran, SDL_Rect positionSerpent[]);
int cogne(SDL_Rect positionSerpent[], SDL_Surface *ecran, int taille);
int surSerpent(SDL_Rect positionSerpent[], int taille);

void demarreSdl(SDL_Surface **ecran, char titre[])
{
    if(SDL_Init(SDL_INIT_VIDEO) == -1)
    {
        fprintf(stderr, "Erreur d'initialisation de la SDL : %s\n", SDL_GetError()); // Ecriture de l'erreur
        exit(EXIT_FAILURE); // On quitte le programme
    }
    SDL_WM_SetIcon(SDL_LoadBMP("ico.bmp"), NULL);
    *ecran = SDL_SetVideoMode(640, 480, 32, SDL_HWSURFACE | SDL_RESIZABLE | SDL_DOUBLEBUF);
    if(*ecran == NULL)
    {
        fprintf(stderr, "Impossible de charger le mode vidéo: %s\n", SDL_GetError());
    }
    SDL_WM_SetCaption(titre, NULL);
    SDL_EnableKeyRepeat(1, 1);
}

void fermeSdl(SDL_Surface *serpent, SDL_Surface *boum)
{
    SDL_FreeSurface(serpent);
    SDL_FreeSurface(boum);
    SDL_Quit();
}

void evenements(SDL_Surface *ecran, SDL_Surface *serpent, SDL_Surface *boum, SDL_Surface *tete[])
{
    int continuer =1, direction=BAS, taille=5, i=0;
    SDL_Event evenement;
    SDL_Rect positionSerpent[TAILLEMAX];
    initialiseSerpent(positionSerpent, serpent, ecran, taille);
    i=100;
    while (continuer)
    {
        SDL_FillRect(ecran, NULL, SDL_MapRGB(ecran->format, 2, 100, 40));

        blitteSerpent(serpent, ecran, positionSerpent, taille, direction, tete);
        SDL_Flip(ecran);

        if(i==100)
        {
            decalePositions(positionSerpent, taille);
            avanceSerpent(serpent, positionSerpent, direction);
            i=0;
        }
        else
        {
            i++;
        }

        if(SDL_PollEvent(&evenement))
        {
            switch(evenement.type)
            {
                case SDL_KEYDOWN:
                    switch(evenement.key.keysym.sym)
                    {
                        case SDLK_RIGHT:
                            if(direction != GAUCHE)
                            direction = DROITE;
                            break;
                        case SDLK_LEFT:
                            if(direction != DROITE)
                            direction = GAUCHE;
                            break;
                        case SDLK_UP:
                            if(direction != BAS)
                            direction = HAUT;
                            break;
                        case SDLK_DOWN:
                            if(direction != HAUT)
                            direction = BAS;
                            break;
                        case SDLK_PLUS:
                        case SDLK_p:
                            if(taille<TAILLEMAX)
                                taille++;
                            break;
                        case SDLK_MINUS:
                        case SDLK_m:
                            if(taille>0)
                                taille--;
                            break;
                        case SDLK_ESCAPE:
                            continuer = 0;
                            break;
                        default:
                            break;
                    }
                    break;
                case SDL_QUIT:
                    continuer =0;
                    break;
                default: break;
            }
        }
        
        if(cogne(positionSerpent, ecran, taille))
        {
            perdu(boum, ecran, positionSerpent);
            continuer =0;
        }
    }
}

void initialise(SDL_Surface *ecran, SDL_Surface **serpent, SDL_Surface **boum, SDL_Surface *tete[])
{
    int i=0;
    char nom[10];
    SDL_FillRect(ecran, NULL, SDL_MapRGB(ecran->format, 2, 100, 40));
    *serpent = SDL_LoadBMP("serpent.bmp");
    *boum = SDL_LoadBMP("boum.bmp");
    for(i=0; i<4; i++)
    {
        sprintf(nom, "tete%d.bmp", i);
        tete[i]= SDL_LoadBMP(nom);
    }
}

void initialiseSerpent(SDL_Rect positionSerpent[], SDL_Surface *serpent, SDL_Surface *ecran, int taille)
{
    puts("foo");
    int i=0;
    for(i=0; i<TAILLEMAX; i++)
    {
        positionSerpent[i].x = ((ecran->w)/2)-((serpent->w)/2);
        positionSerpent[i].y = ((ecran->h/2)-(serpent->h/2));
    }
    puts("bar");
}

void blitteSerpent(SDL_Surface *serpent, SDL_Surface *ecran, SDL_Rect positionSerpent[], int taille, int direction, SDL_Surface *tete[])
{
    int i;
    SDL_Rect positionTete;
    positionTete.x = positionSerpent[0].x;
    positionTete.y = positionSerpent[0].y;
    switch(direction)
    {
        case BAS:
            positionTete.x = positionSerpent[0].x+tete[0]->w-serpent->w;
            SDL_BlitSurface(tete[0], NULL, ecran, &positionTete);
            break;
        case DROITE:
            positionTete.y = positionSerpent[0].y+tete[1]->h-serpent->h;
            SDL_BlitSurface(tete[1], NULL, ecran, &positionTete);
            break;
        case HAUT:
            positionTete.y = positionSerpent[0].y-tete[2]->h+serpent->h;
            SDL_BlitSurface(tete[2], NULL, ecran, &positionTete);
            break;
        case GAUCHE:
            positionTete.x = positionSerpent[0].x-tete[3]->w+serpent->w;
            SDL_BlitSurface(tete[3], NULL, ecran, &positionTete);
            break;
    }
    for(i=1; i<taille; i++)
    {
        SDL_BlitSurface(serpent, NULL, ecran, &positionSerpent[i]);
    }
}

void decalePositions(SDL_Rect positionSerpent[], int taille)
{
    int i;
    for(i=1; i<TAILLEMAX; i++)
    {
        positionSerpent[TAILLEMAX-i].x = positionSerpent[TAILLEMAX-i-1].x;
        positionSerpent[TAILLEMAX-i].y = positionSerpent[TAILLEMAX-i-1].y;
    }
}

void avanceSerpent(SDL_Surface *serpent, SDL_Rect positionSerpent[], int direction)
{
    switch(direction)
    {
        case BAS:
            positionSerpent[0].y+=serpent->h+1;
            break;
        case DROITE:
            positionSerpent[0].x+=serpent->w+1;
            break;
        case HAUT:
            positionSerpent[0].y-=serpent->h+1;
            break;
        case GAUCHE:
            positionSerpent[0].x-=serpent->w+1;
            break;
    }
}

int cogne(SDL_Rect positionSerpent[], SDL_Surface *ecran, int taille)
{
    if(positionSerpent[0].x <0 || positionSerpent[0].x >= ecran->w || positionSerpent[0].y<0 || positionSerpent[0].y >= ecran->h)
    {
        return 1;
    }
    else if(surSerpent(positionSerpent, taille))
    {
        return 1;
    }
    else
    {
        return 0;
    }
}

int surSerpent(SDL_Rect positionSerpent[], int taille)
{
    int resultat=0, i;
    for(i=1; i<taille; i++)
    {
        if(positionSerpent[0].x == positionSerpent[i].x && positionSerpent[0].y == positionSerpent[i].y)
        {
            resultat = 1;
        }
    }
    return resultat;
}

void perdu(SDL_Surface *boum, SDL_Surface *ecran, SDL_Rect positionSerpent[])
{
    SDL_Rect position;
    printf("Out !!%d\n", positionSerpent[0].x);
    position.x=ecran->w/2-boum->w/2;
    position.y=ecran->h/2-boum->h/2;
    printf("%d, %d:%d", SDL_BlitSurface(boum, NULL, ecran, &position), position.x, position.y);
}

int main(int argc, char* argv[])
{
    SDL_Surface *ecran, *serpent, *boum, *tete[4];
    char titre[20] = "Snake";
    
    demarreSdl(&ecran, titre);
    
    initialise(ecran, &serpent, &boum, tete);
    
    evenements(ecran, serpent, boum, tete);
    
    fermeSdl(serpent, boum);
    return 0;
}