/*
 * pg_column_map.c - PG::ColumnMap class extension
 * $Id: pg_type_map.c,v c99d26015e3c 2014/12/12 20:58:25 lars $
 *
 */

#include "pg.h"

VALUE rb_cTypeMap;
VALUE rb_mDefaultTypeMappable;
static ID s_id_fit_to_query;
static ID s_id_fit_to_result;

VALUE
pg_typemap_fit_to_result( VALUE self, VALUE result )
{
	rb_raise( rb_eNotImpError, "type map %s is not suitable to map result values", rb_obj_classname(self) );
	return Qnil;
}

VALUE
pg_typemap_fit_to_query( VALUE self, VALUE params )
{
	rb_raise( rb_eNotImpError, "type map %s is not suitable to map query params", rb_obj_classname(self) );
	return Qnil;
}

int
pg_typemap_fit_to_copy_get( VALUE self )
{
	rb_raise( rb_eNotImpError, "type map %s is not suitable to map get_copy_data results", rb_obj_classname(self) );
	return Qnil;
}

VALUE
pg_typemap_result_value( t_typemap *p_typemap, VALUE result, int tuple, int field )
{
	rb_raise( rb_eNotImpError, "type map is not suitable to map result values" );
	return Qnil;
}

t_pg_coder *
pg_typemap_typecast_query_param( t_typemap *p_typemap, VALUE param_value, int field )
{
	rb_raise( rb_eNotImpError, "type map is not suitable to map query params" );
	return NULL;
}

VALUE
pg_typemap_typecast_copy_get( t_typemap *p_typemap, VALUE field_str, int fieldno, int format, int enc_idx )
{
	rb_raise( rb_eNotImpError, "type map is not suitable to map get_copy_data results" );
	return Qnil;
}

const struct pg_typemap_funcs pg_typemap_funcs = {
	.fit_to_result = pg_typemap_fit_to_result,
	.fit_to_query = pg_typemap_fit_to_query,
	.fit_to_copy_get = pg_typemap_fit_to_copy_get,
	.typecast_result_value = pg_typemap_result_value,
	.typecast_query_param = pg_typemap_typecast_query_param,
	.typecast_copy_get = pg_typemap_typecast_copy_get
};

static VALUE
pg_typemap_s_allocate( VALUE klass )
{
	VALUE self;
	t_typemap *this;

	self = Data_Make_Struct( klass, t_typemap, NULL, -1, this );
	this->funcs = pg_typemap_funcs;

	return self;
}

/*
 * call-seq:
 *    res.default_type_map = typemap
 *
 * Set the default TypeMap that is used for values that could not be
 * casted by this type map.
 *
 * +typemap+ must be a kind of PG::TypeMap
 *
 */
static VALUE
pg_typemap_default_type_map_set(VALUE self, VALUE typemap)
{
	t_typemap *this = DATA_PTR( self );

	if ( !rb_obj_is_kind_of(typemap, rb_cTypeMap) ) {
		rb_raise( rb_eTypeError, "wrong argument type %s (expected kind of PG::TypeMap)",
				rb_obj_classname( typemap ) );
	}
	Check_Type(typemap, T_DATA);
	this->default_typemap = typemap;

	return typemap;
}

/*
 * call-seq:
 *    res.default_type_map -> TypeMap
 *
 * Returns the default TypeMap that is currently set for values that could not be
 * casted by this type map.
 *
 * Returns a kind of PG::TypeMap.
 *
 */
static VALUE
pg_typemap_default_type_map_get(VALUE self)
{
	t_typemap *this = DATA_PTR( self );

	return this->default_typemap;
}

/*
 * call-seq:
 *    res.with_default_type_map( typemap )
 *
 * Set the default TypeMap that is used for values that could not be
 * casted by this type map.
 *
 * +typemap+ must be a kind of PG::TypeMap
 *
 * Returns self.
 */
static VALUE
pg_typemap_with_default_type_map(VALUE self, VALUE typemap)
{
	pg_typemap_default_type_map_set( self, typemap );
	return self;
}

void
init_pg_type_map()
{
	s_id_fit_to_query = rb_intern("fit_to_query");
	s_id_fit_to_result = rb_intern("fit_to_result");

	/*
	 * Document-class: PG::TypeMap < Object
	 *
	 * This is the base class for type maps.
	 * See derived classes for implementations of different type cast strategies
	 * ( PG::TypeMapByColumn, PG::TypeMapByOid ).
	 *
	 */
	rb_cTypeMap = rb_define_class_under( rb_mPG, "TypeMap", rb_cObject );
	rb_define_alloc_func( rb_cTypeMap, pg_typemap_s_allocate );

	rb_mDefaultTypeMappable = rb_define_module_under( rb_cTypeMap, "DefaultTypeMappable");
	rb_define_method( rb_mDefaultTypeMappable, "default_type_map=", pg_typemap_default_type_map_set, 1 );
	rb_define_method( rb_mDefaultTypeMappable, "default_type_map", pg_typemap_default_type_map_get, 0 );
	rb_define_method( rb_mDefaultTypeMappable, "with_default_type_map", pg_typemap_with_default_type_map, 1 );
}
