#include "parse_url.h"
#include "string.h"

int main(void){
  //uint8_t header[]="HTTP/1.1 200 OK\r\nFoo: bar\r\nCookies: Yes Please\r\n\r\n";
  uint8_t url[]="http://www.google.com:80/foobar";
  struct domain out = {.port=80};
  get_protocol(url,&out,url+strlen((char*)url)-1);
  //printf("%s,%s,%d,%s,%d",out.protocol,out.domain,out.port,out.path,out.success);
  return 0;
}

ERL_NIF_TERM parse_url(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
{
  ErlNifBinary block;
  ERL_NIF_TERM path, output;
  struct domain out = {.port=80,.success=false};

  if (enif_is_binary(env,argv[0])==false) return enif_make_atom(env, "error");
  enif_inspect_binary(env, argv[0], &block);
  if (block.size<4) return enif_make_atom(env, "error");
  get_protocol(block.data,&out,block.data+block.size-1);
  if (out.success==false) return enif_make_atom(env, "error");
  //fprintf(stderr,"%d %d --
  //",(int)(block.size-out.path-1),(int)out.path);
  if (out.path==0){
    unsigned char dat[1]={'/'};
    ErlNifBinary bin={.size=1,.data=dat};
    path=enif_make_binary(env,&bin);
  }
  else{
    path=enif_make_sub_binary(env, argv[0], block.size-out.path , out.path);
  }
  
  output=enif_make_tuple4(env
                          , enif_make_binary(env, &out.protocol)
                          , enif_make_binary(env, &out.domain)
                          , enif_make_int(env,out.port)
                          , path
                          );
  free(out.protocol.data);
  free(out.domain.data);
  return output;
}



inline void get_protocol(uint8_t* s, struct domain* out, uint8_t* len){
  uint8_t* i, *protocol;
  if ((i=memchr(s,':',len-s+1)) != NULL){
    protocol = malloc(i-s);
    memcpy(protocol,s,i-s);
    //strncpy((char*)protocol,(char *)s,i-s);
    lower(protocol,protocol+(i-s)+1);
    out->protocol.size=i-s;
    out->protocol.data=protocol;
    //    printf("%s\n",out->protocol);
    return get_domain(i+3,out,len);
  } else{
    protocol=malloc(4);
    strncpy((char*)protocol,"http",4);
    out->protocol.size=4;
    out->protocol.data=protocol;
    return get_domain(s,out,len);
  }
}

inline void get_domain(uint8_t* s, struct domain* out, uint8_t* len){
  uint8_t* i=s, *domain;
  while(*i != ':' && *i !='/' && i<len+1) i++;

  if (i==s) return; //badarg
  domain = malloc(i-s);
  memcpy(domain,s,i-s);
  //  strncpy((char*)domain,(char *)s,i-s);
  lower(domain,domain+(i-s)+1);
  out->domain.size=i-s;
  out->domain.data=domain;
  //  printf("%s\n",out->domain);
  if (*i == '/'){
    return get_path(i,out,len);
  } else if(*i==':'){
    return get_port(i+1,out,len);
  } else if(i>len-1){
    out->success=true;
    return;
  } else return; //badarg
}


inline void get_port(uint8_t* s, struct domain* out, uint8_t* len){
  uint8_t* i=s, *port;
  i=memchr(s,'/',len-s+1);
  if (i==s || i-s>5) return; //badarg
  if (i==NULL){
    out->success=true;
    return;
  } else {
    port=malloc(6);
    strncpy((char*)port,(char *)s,i-s);
    port[5]='\0';
    out->port=atoi((char*)port);
    free(port);
    return get_path(i,out,len);
  }
}

inline void get_path(uint8_t* s, struct domain* out, uint8_t* len){
  out->path=len-s+1;
  /* uint8_t *path; */
  /* out->success=true; */
  /* if (len-s==-1) return; */
  /* path = malloc(len-s+1); */
  /* strncpy((char*)path,(char *)s,len-s+1); */
  out->success=true;
  /* out->path.size=len-s+1; */
  /* out->path.data=path; */
  //  printf("%s\n",out->path);
}

inline void lower(uint8_t* s,uint8_t* end){
  while(s++<end) if (*s>'A'-1 && *s<'Z'+1) *s+=32;
}