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

#define P2(a) a*a

struct camera{
    double x,y,width,height;
};

struct render{
    double omin_x,omax_x,omin_y,omax_y;
    int H,W,max_iter,radius,a,b;
    int img[1000][1000];
    char basename[256];
    struct camera pov;
};

double map(int v, int imin, int imax, double omin, double omax);
void render_init(struct render *set, int argc, char *argv[]);
void render_image(struct render *set);
void image_save_bw(struct render *set);
void image_save_altern(struct render *set);
void cam2rect(struct render *set, struct camera *pov);

int main(int argc, char *argv[]){
    int comp=1;/*compteur pour gérer le strtok*/
    struct render set;
    char *co;
    set.pov.x=-1.142817421949293;
    set.pov.y=-0.21198254168631775;
    set.pov.width=0.0055;
    set.pov.height=0.0055;
    if (argc==3){/*si argc=3 alors il faut changer les valeurs*/
    co=strtok(argv[2],",");
    while(co!=NULL){
        if (comp==1){
            set.pov.x=atof(co);
        }
        if (comp==2){
            set.pov.y=atof(co);
        }
        if (comp==3){
            set.pov.width=atof(co);
        }
        if (comp==4){
            set.pov.height=atof(co);
        }
        co=strtok(NULL,s);
        comp++;
    }
    }
    render_init(&set,argc,argv);  
    cam2rect(&set,&set.pov);
    render_image(&set);
    image_save_altern(&set);
    return 0;
}

double map(int v, int imin, int imax, double omin, double omax){
    float x;
    x=v-imin;
    x=x/(imax-imin);
    x=x*(omax-omin);
    x+=omin;
    return x;
}   

void render_init(struct render *set, int argc, char *argv[]){
    set->omin_x=-2;
    set->omax_x=0.48;
    set->omin_y=-1.24;
    set->omax_y=1.24;
    set->H=1000;
    set->W=1000;
    set->max_iter=1000;
    if (argc==2){/*si argc=2 on change max_iter qui est 1000 par défaut*/
        set->max_iter=strtol(argv[1],NULL,10);
    }
    set->radius=2;
    strcpy(set->basename,"mandel.pbm");
}

void render_image(struct render *set){
    float y=1,x=1,x0=1,y0=1,xc=1,pcent=1;/*pcent=pourcentage*/
    int i=1,j=1,compteur=1;/*compteur=compte le nombre d'itérations avant divergence*/
    for (i=0;i<set->H;i++){
        pcent=100*i*1.00/set->H;
        printf("%.2f %c\r",pcent,'%');
        for (j=0;j<set->W;j++){/*x*/
            x=map(j,0,set->W,set->omin_x,set->omax_x);
            y=map(i,0,set->H,set->omin_y,set->omax_y);
            compteur=1;
            x0=x;
            y0=y;
            while ((sqrt(P2(x)+P2(y))<=set->radius)&&(compteur<set->max_iter)){
                xc=x;
                x=P2(xc)-P2(y)+x0;
                y=2*xc*y+y0;
                compteur+=1;
            }
            set->img[i][j]=compteur;
        }
    } 
    printf("\n");
}

void image_save_bw(struct render *set){
    int i,j;
    char format[5]="P1";
    FILE *fout;
    strcpy(set->basename,"mandel_bw.pbm"); 
    fout=fopen(set->basename,"w");
    if (fout==NULL){
        printf("Erreur\n");
        return ;
    }
    fprintf(fout,"%s\n%d %d\n",format,set->H,set->W);
    for (i=0;i<set->H;i++){
        for (j=0;j<set->W;j++){/*x*/
            if ((set->img[i][j])==set->max_iter){
                fputc('1',fout);
            }
            else{
                fputc('0',fout);    
            }
        }
        fprintf(fout,"\n");
    }
    fclose(fout);
}

void image_save_altern(struct render *set){
    int i,j;
    char format[5]="P1";
    FILE *fout;
    strcpy(set->basename,"mandel_altern.pbm"); 
    fout=fopen(set->basename,"w");
    if (fout==NULL){
        printf("Erreur\n");
        return ;
    }
    fprintf(fout,"%s\n%d %d\n",format,set->H,set->W);
    for (i=0;i<set->H;i++){
        for (j=0;j<set->W;j++){/*x*/
            if (((set->img[i][j])==set->max_iter)||(set->img[i][j]%2==1)){
                fputc('1',fout);
            }
            else{
                fputc('0',fout);    
            }
        }
        fprintf(fout,"\n");
    }
    fclose(fout);
}

void cam2rect(struct render *set, struct camera *pov){
    set->omin_x=pov->x-pov->width/2.0;
    set->omax_x=pov->x+pov->width/2.0;
    set->omin_y=pov->y-pov->height/2.0;
    set->omax_y=pov->y+pov->height/2.0;
}