#include "hash_ext.h"
#include "enumerable.c"

static VALUE mJSON;
static VALUE cCircularDatastructure;

void Init_hash_ext() {
  mJSON = rb_const_get(rb_cObject, rb_intern("JSON"));
  rb_cJsonState = rb_const_get(mJSON, rb_intern("State"));
  cCircularDatastructure = rb_const_get(mJSON, rb_intern("CircularDatastructure"));
  rb_define_method(rb_cHash, "to_json", (VALUE(*)(ANYARGS)) &to_json, -1);
}

/** private **/

static VALUE json_transform(self, state, depth)
  VALUE self, state, depth;
{
  VALUE delim = rb_str_new2(",");
  VALUE object_nl = Qnil;
  if(state != Qnil) object_nl = rb_funcall(state, rb_intern("object_nl"), 0);
  new_line(delim, object_nl);

  VALUE result = rb_str_new2("{");
  new_line(result, object_nl);

  process_internal_json(self, result, state, depth, delim, object_nl);

  new_line(result, object_nl);
  if(rb_json_should_shift(state, object_nl) == Qtrue) json_shift(result, state, depth);
  rb_str_append(result, rb_str_new2("}"));
  return result;
}

static VALUE process_internal_json(self, json, state, depth, delim, object_nl)
  VALUE self, json, state, depth, delim, object_nl;
{
  // TODO: Use st_foreach for even better performance
  VALUE key_value_pairs = rb_funcall(self, rb_intern("to_a"), 0);
  VALUE new_depth = LONG2NUM(NUM2LONG(depth) + 1);
  VALUE space = rb_funcall(state, rb_intern("space"), 0);

  VALUE key_value = Qnil;
  int i;
  for(i = 0; i < RARRAY(key_value_pairs)->len; i++) {
    if(i > 0) {
      rb_str_concat(json, delim);
    }
    key_value = rb_ary_entry(key_value_pairs, i);
    VALUE key = rb_ary_entry(key_value, 0);
    VALUE value = rb_ary_entry(key_value, 1);

    if(rb_json_should_shift(state, object_nl) == Qtrue) json_shift(json, state, depth);
    VALUE key_string = rb_funcall(key, rb_intern("to_s"), 0);
    rb_str_append(json, rb_to_json(key_string, state, new_depth));
    rb_str_cat2(json, ":");
    rb_str_append(json, space);
    rb_str_append(json, rb_to_json(value, state, new_depth));
  }
}