#include "unf/normalizer.hh"

#include <ruby.h>
#if defined(HAVE_RUBY_ENCODING_H)
#include <ruby/encoding.h>
#endif

extern "C" {
  VALUE unf_allocate(VALUE klass);
  VALUE unf_initialize(VALUE self);
  void unf_delete(void* ptr);
  VALUE unf_normalize(VALUE self, VALUE source, VALUE normalization_form);

  ID FORM_NFD;
  ID FORM_NFC;
  ID FORM_NFKD;
  ID FORM_NFKC;

  void Init_unf_ext() {
    VALUE mdl = rb_define_module("UNF");

    VALUE cls = rb_define_class_under(mdl, "Normalizer", rb_cObject);
    rb_define_alloc_func(cls, unf_allocate);
    rb_define_method(cls, "initialize", (VALUE (*)(...))unf_initialize, 0);
    rb_define_method(cls, "normalize", (VALUE (*)(...))unf_normalize, 2);

    FORM_NFD = rb_intern("nfd");
    FORM_NFC = rb_intern("nfc");
    FORM_NFKD= rb_intern("nfkd");
    FORM_NFKC= rb_intern("nfkc");
  }

  static const rb_data_type_t unf_normalizer_data_type = {
    .wrap_struct_name = "UNF::Normalizer",
    .function = {
      .dmark = NULL,
      .dfree = unf_delete,
      .dsize = NULL
    },
    .parent = NULL,
    .data = NULL,
    .flags = RUBY_TYPED_FREE_IMMEDIATELY | RUBY_TYPED_WB_PROTECTED
  };

  VALUE unf_allocate(VALUE klass) {
    UNF::Normalizer* ptr;
    VALUE obj = TypedData_Make_Struct(klass, UNF::Normalizer, &unf_normalizer_data_type, ptr);
    new ((void*)ptr) UNF::Normalizer;
    return obj;
  }

  VALUE unf_initialize(VALUE self) {
    return self;
  }

  void unf_delete(void *data) {
    UNF::Normalizer* ptr = (UNF::Normalizer*)data;
    ptr->~Normalizer();
    ruby_xfree(ptr);
  }

  VALUE unf_normalize(VALUE self, VALUE source, VALUE normalization_form) {
    UNF::Normalizer* ptr;
    TypedData_Get_Struct(self, UNF::Normalizer, &unf_normalizer_data_type, ptr);

    const char* src = StringValueCStr(source);
    const char* rlt;
    ID form_id = SYM2ID(normalization_form);

    if(form_id == FORM_NFD)
      rlt = ptr->normalize(src, UNF::Normalizer::FORM_NFD);
    else if(form_id == FORM_NFC)
      rlt = ptr->normalize(src, UNF::Normalizer::FORM_NFC);
    else if(form_id == FORM_NFKD)
      rlt = ptr->normalize(src, UNF::Normalizer::FORM_NFKD);
    else if(form_id == FORM_NFKC)
      rlt = ptr->normalize(src, UNF::Normalizer::FORM_NFKC);
    else
      rb_raise(rb_eArgError, "Specified Normalization-Form is unknown. Please select one from among :nfc, :nfd, :nfkc, :nfkd.");

#if defined(HAVE_RUBY_ENCODING_H)
    return rb_enc_str_new(rlt, strlen(rlt), rb_utf8_encoding());
#else
    return rb_str_new2(rlt);
#endif
  }
}