/* Copyright (C) 2005-2011 Shugo Maeda <shugo@ruby-lang.org> and Charlie Savage <cfis@savagexi.com>
   Please see the LICENSE file for copyright and distribution information */

#include "ruby_prof.h"

VALUE cMethodInfo;

/* ================  Helper Functions  =================*/
static VALUE
figure_singleton_name(VALUE klass)
{
    VALUE result = Qnil;

    /* We have come across a singleton object. First
       figure out what it is attached to.*/
    VALUE attached = rb_iv_get(klass, "__attached__");

    /* Is this a singleton class acting as a metaclass? */
    if (BUILTIN_TYPE(attached) == T_CLASS)
    {
        result = rb_str_new2("<Class::");
        rb_str_append(result, rb_inspect(attached));
        rb_str_cat2(result, ">");
    }

    /* Is this for singleton methods on a module? */
    else if (BUILTIN_TYPE(attached) == T_MODULE)
    {
        result = rb_str_new2("<Module::");
        rb_str_append(result, rb_inspect(attached));
        rb_str_cat2(result, ">");
    }

    /* Is this for singleton methods on an object? */
    else if (BUILTIN_TYPE(attached) == T_OBJECT)
    {
        /* Make sure to get the super class so that we don't
           mistakenly grab a T_ICLASS which would lead to
           unknown method errors. */
#ifdef HAVE_RB_CLASS_SUPERCLASS
        // 1.9.3
        VALUE super = rb_class_superclass(klass);
#else
# ifdef RCLASS_SUPER
        VALUE super = rb_class_real(RCLASS_SUPER(klass));
# else
        VALUE super = rb_class_real(RCLASS(klass)->super);
# endif
#endif
        result = rb_str_new2("<Object::");
        rb_str_append(result, rb_inspect(super));
        rb_str_cat2(result, ">");
    }

    /* Ok, this could be other things like an array made put onto
       a singleton object (yeah, it happens, see the singleton
       objects test case). */
    else
    {
        result = rb_inspect(klass);
    }

    return result;
}

static VALUE
klass_name(VALUE klass)
{
    VALUE result = Qnil;

    if (klass == 0 || klass == Qnil)
    {
        result = rb_str_new2("Global");
    }
    else if (BUILTIN_TYPE(klass) == T_MODULE)
    {
        result = rb_inspect(klass);
    }
    else if (BUILTIN_TYPE(klass) == T_CLASS && FL_TEST(klass, FL_SINGLETON))
    {
        result = figure_singleton_name(klass);
    }
    else if (BUILTIN_TYPE(klass) == T_CLASS)
    {
        result = rb_inspect(klass);
    }
    else
    {
        /* Should never happen. */
        result = rb_str_new2("Unknown");
    }

    return result;
}

static VALUE
method_name(ID mid)
{
    VALUE result;

    if (mid == ID_ALLOCATOR)
        result = rb_str_new2("allocate");
    else if (mid == 0)
        result = rb_str_new2("[No method]");
    else
        result = rb_String(ID2SYM(mid));

    return result;
}

static VALUE
full_name(VALUE klass, ID mid)
{
  VALUE result = klass_name(klass);
  rb_str_cat2(result, "#");
  rb_str_append(result, method_name(mid));

  return result;
}


/* ================  Method Table   =================*/
int
method_table_cmp(prof_method_key_t *key1, prof_method_key_t *key2)
{
    return (key1->klass != key2->klass) || (key1->mid != key2->mid);
}

st_index_t
method_table_hash(prof_method_key_t *key)
{
    return key->key;
}

struct st_hash_type type_method_hash = {
    method_table_cmp,
    method_table_hash
};

st_table *
method_table_create()
{
  return st_init_table(&type_method_hash);
}

size_t
method_table_insert(st_table *table, const prof_method_key_t *key, prof_method_t *val)
{
  return st_insert(table, (st_data_t) key, (st_data_t) val);
}

prof_method_t *
method_table_lookup(st_table *table, const prof_method_key_t* key)
{
    st_data_t val;
    if (st_lookup(table, (st_data_t)key, &val))
    {
      return (prof_method_t *) val;
    }
    else
    {
      return NULL;
    }
}

void
method_table_free(st_table *table)
{
    /* Don't free the contents since they are wrapped by
       Ruby objects! */
    st_free_table(table);
}


/* ================  Method Info   =================*/
/* Document-class: RubyProf::MethodInfo
The RubyProf::MethodInfo class stores profiling data for a method.
One instance of the RubyProf::MethodInfo class is created per method
called per thread.  Thus, if a method is called in two different
thread then there will be two RubyProf::MethodInfo objects
created.  RubyProf::MethodInfo objects can be accessed via
the RubyProf::Result object.
*/

prof_method_t*
prof_method_create(prof_method_key_t *key, const char* source_file, int line)
{
    prof_method_t *result = ALLOC(prof_method_t);
    result->object = Qnil;
    result->key = ALLOC(prof_method_key_t);
    method_key(result->key, key->klass, key->mid);

    result->call_infos = prof_call_infos_create();

    if (source_file != NULL)
    {
      size_t len = strlen(source_file) + 1;
      char *buffer = ALLOC_N(char, len);

      MEMCPY(buffer, source_file, char, len);
      result->source_file = buffer;
    }
    else
    {
      result->source_file = source_file;
    }
    result->line = line;

    return result;
}

void
prof_method_mark(prof_method_t *method)
{
  rb_gc_mark(method->call_infos->object);
  rb_gc_mark(method->key->klass);
}

static void
prof_method_free(prof_method_t *method)
{
  if (method->source_file)
  {
    xfree((char*)method->source_file);
  }

  prof_call_infos_free(method->call_infos);
  xfree(method->key);
  xfree(method);
}

VALUE
prof_method_wrap(prof_method_t *result)
{
  if (result->object == Qnil)
  {
    result->object = Data_Wrap_Struct(cMethodInfo, prof_method_mark, prof_method_free, result);
  }
  return result->object;
}

static prof_method_t *
get_prof_method(VALUE obj)
{
    return (prof_method_t *) DATA_PTR(obj);
}

/* call-seq:
   line_no -> int

   returns the line number of the method */
static VALUE
prof_method_line(VALUE self)
{
    return rb_int_new(get_prof_method(self)->line);
}

/* call-seq:
   source_file => string

return the source file of the method
*/
static VALUE prof_method_source_file(VALUE self)
{
    const char* sf = get_prof_method(self)->source_file;
    if(!sf)
    {
      return rb_str_new2("ruby_runtime");
    }
    else
    {
      return rb_str_new2(sf);
    }
}


/* call-seq:
   method_class -> klass

Returns the Ruby klass that owns this method. */
static VALUE
prof_method_klass(VALUE self)
{
    prof_method_t *result = get_prof_method(self);
    return result->key->klass;
}

/* call-seq:
   method_id -> ID

Returns the id of this method. */
static VALUE
prof_method_id(VALUE self)
{
    prof_method_t *result = get_prof_method(self);
    return ID2SYM(result->key->mid);
}

/* call-seq:
   klass_name -> string

Returns the name of this method's class.  Singleton classes
will have the form <Object::Object>. */

static VALUE
prof_klass_name(VALUE self)
{
    prof_method_t *method = get_prof_method(self);
    return klass_name(method->key->klass);
}

/* call-seq:
   method_name -> string

Returns the name of this method in the format Object#method.  Singletons
methods will be returned in the format <Object::Object>#method.*/

static VALUE
prof_method_name(VALUE self)
{
    prof_method_t *method = get_prof_method(self);
    return method_name(method->key->mid);
}

/* call-seq:
   full_name -> string

Returns the full name of this method in the format Object#method.*/

static VALUE
prof_full_name(VALUE self)
{
    prof_method_t *method = get_prof_method(self);
    return full_name(method->key->klass, method->key->mid);
}

/* call-seq:
   call_infos -> Array of call_info

Returns an array of call info objects that contain profiling information
about the current method.*/
static VALUE
prof_method_call_infos(VALUE self)
{
    prof_method_t *method = get_prof_method(self);
    return prof_call_infos_wrap(method->call_infos);
}

void rp_init_method_info()
{
    /* MethodInfo */
    cMethodInfo = rb_define_class_under(mProf, "MethodInfo", rb_cObject);
    rb_undef_method(CLASS_OF(cMethodInfo), "new");

    rb_define_method(cMethodInfo, "klass", prof_method_klass, 0);
    rb_define_method(cMethodInfo, "klass_name", prof_klass_name, 0);
    rb_define_method(cMethodInfo, "method_name", prof_method_name, 0);
    rb_define_method(cMethodInfo, "full_name", prof_full_name, 0);
    rb_define_method(cMethodInfo, "method_id", prof_method_id, 0);
    rb_define_method(cMethodInfo, "source_file", prof_method_source_file,0);
    rb_define_method(cMethodInfo, "line", prof_method_line, 0);
    rb_define_method(cMethodInfo, "call_infos", prof_method_call_infos, 0);
}