peerplays_migrated/libraries/chain/include/graphene/chain/asset_object.hpp
2016-03-09 14:37:33 +01:00

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/*
* Copyright (c) 2015 Cryptonomex, Inc., and contributors.
*
* The MIT License
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#pragma once
#include <graphene/chain/protocol/asset_ops.hpp>
#include <boost/multi_index/composite_key.hpp>
#include <graphene/db/flat_index.hpp>
#include <graphene/db/generic_index.hpp>
/**
* @defgroup prediction_market Prediction Market
*
* A prediction market is a specialized BitAsset such that total debt and total collateral are always equal amounts
* (although asset IDs differ). No margin calls or force settlements may be performed on a prediction market asset. A
* prediction market is globally settled by the issuer after the event being predicted resolves, thus a prediction
* market must always have the @ref global_settle permission enabled. The maximum price for global settlement or short
* sale of a prediction market asset is 1-to-1.
*/
namespace graphene { namespace chain {
class account_object;
class database;
using namespace graphene::db;
/**
* @brief tracks the asset information that changes frequently
* @ingroup object
* @ingroup implementation
*
* Because the asset_object is very large it doesn't make sense to save an undo state
* for all of the parameters that never change. This object factors out the parameters
* of an asset that change in almost every transaction that involves the asset.
*
* This object exists as an implementation detail and its ID should never be referenced by
* a blockchain operation.
*/
class asset_dynamic_data_object : public abstract_object<asset_dynamic_data_object>
{
public:
static const uint8_t space_id = implementation_ids;
static const uint8_t type_id = impl_asset_dynamic_data_type;
/// The number of shares currently in existence
share_type current_supply;
share_type confidential_supply; ///< total asset held in confidential balances
share_type accumulated_fees; ///< fees accumulate to be paid out over time
share_type fee_pool; ///< in core asset
};
/**
* @brief tracks the parameters of an asset
* @ingroup object
*
* All assets have a globally unique symbol name that controls how they are traded and an issuer who
* has authority over the parameters of the asset.
*/
class asset_object : public graphene::db::abstract_object<asset_object>
{
public:
static const uint8_t space_id = protocol_ids;
static const uint8_t type_id = asset_object_type;
/// This function does not check if any registered asset has this symbol or not; it simply checks whether the
/// symbol would be valid.
/// @return true if symbol is a valid ticker symbol; false otherwise.
static bool is_valid_symbol( const string& symbol );
/// @return true if this is a market-issued asset; false otherwise.
bool is_market_issued()const { return bitasset_data_id.valid(); }
/// @return true if users may request force-settlement of this market-issued asset; false otherwise
bool can_force_settle()const { return !(options.flags & disable_force_settle); }
/// @return true if the issuer of this market-issued asset may globally settle the asset; false otherwise
bool can_global_settle()const { return options.issuer_permissions & global_settle; }
/// @return true if this asset charges a fee for the issuer on market operations; false otherwise
bool charges_market_fees()const { return options.flags & charge_market_fee; }
/// @return true if this asset may only be transferred to/from the issuer or market orders
bool is_transfer_restricted()const { return options.flags & transfer_restricted; }
bool can_override()const { return options.flags & override_authority; }
bool allow_confidential()const { return !(options.flags & asset_issuer_permission_flags::disable_confidential); }
/// Helper function to get an asset object with the given amount in this asset's type
asset amount(share_type a)const { return asset(a, id); }
/// Convert a string amount (i.e. "123.45") to an asset object with this asset's type
/// The string may have a decimal and/or a negative sign.
asset amount_from_string(string amount_string)const;
/// Convert an asset to a textual representation, i.e. "123.45"
string amount_to_string(share_type amount)const;
/// Convert an asset to a textual representation, i.e. "123.45"
string amount_to_string(const asset& amount)const
{ FC_ASSERT(amount.asset_id == id); return amount_to_string(amount.amount); }
/// Convert an asset to a textual representation with symbol, i.e. "123.45 USD"
string amount_to_pretty_string(share_type amount)const
{ return amount_to_string(amount) + " " + symbol; }
/// Convert an asset to a textual representation with symbol, i.e. "123.45 USD"
string amount_to_pretty_string(const asset &amount)const
{ FC_ASSERT(amount.asset_id == id); return amount_to_pretty_string(amount.amount); }
/// Ticker symbol for this asset, i.e. "USD"
string symbol;
/// Maximum number of digits after the decimal point (must be <= 12)
uint8_t precision = 0;
/// ID of the account which issued this asset.
account_id_type issuer;
asset_options options;
/// Current supply, fee pool, and collected fees are stored in a separate object as they change frequently.
asset_dynamic_data_id_type dynamic_asset_data_id;
/// Extra data associated with BitAssets. This field is non-null if and only if is_market_issued() returns true
optional<asset_bitasset_data_id_type> bitasset_data_id;
optional<account_id_type> buyback_account;
asset_id_type get_id()const { return id; }
void validate()const
{
// UIAs may not be prediction markets, have force settlement, or global settlements
if( !is_market_issued() )
{
FC_ASSERT(!(options.flags & disable_force_settle || options.flags & global_settle));
FC_ASSERT(!(options.issuer_permissions & disable_force_settle || options.issuer_permissions & global_settle));
}
}
template<class DB>
const asset_bitasset_data_object& bitasset_data(const DB& db)const
{ assert(bitasset_data_id); return db.get(*bitasset_data_id); }
template<class DB>
const asset_dynamic_data_object& dynamic_data(const DB& db)const
{ return db.get(dynamic_asset_data_id); }
/**
* The total amount of an asset that is reserved for future issuance.
*/
template<class DB>
share_type reserved( const DB& db )const
{ return options.max_supply - dynamic_data(db).current_supply; }
};
/**
* @brief contains properties that only apply to bitassets (market issued assets)
*
* @ingroup object
* @ingroup implementation
*/
class asset_bitasset_data_object : public abstract_object<asset_bitasset_data_object>
{
public:
static const uint8_t space_id = implementation_ids;
static const uint8_t type_id = impl_asset_bitasset_data_type;
/// The tunable options for BitAssets are stored in this field.
bitasset_options options;
/// Feeds published for this asset. If issuer is not committee, the keys in this map are the feed publishing
/// accounts; otherwise, the feed publishers are the currently active committee_members and witnesses and this map
/// should be treated as an implementation detail. The timestamp on each feed is the time it was published.
flat_map<account_id_type, pair<time_point_sec,price_feed>> feeds;
/// This is the currently active price feed, calculated as the median of values from the currently active
/// feeds.
price_feed current_feed;
/// This is the publication time of the oldest feed which was factored into current_feed.
time_point_sec current_feed_publication_time;
/// True if this asset implements a @ref prediction_market
bool is_prediction_market = false;
/// This is the volume of this asset which has been force-settled this maintanence interval
share_type force_settled_volume;
/// Calculate the maximum force settlement volume per maintenance interval, given the current share supply
share_type max_force_settlement_volume(share_type current_supply)const;
/** return true if there has been a black swan, false otherwise */
bool has_settlement()const { return !settlement_price.is_null(); }
/**
* In the event of a black swan, the swan price is saved in the settlement price, and all margin positions
* are settled at the same price with the siezed collateral being moved into the settlement fund. From this
* point on no further updates to the asset are permitted (no feeds, etc) and forced settlement occurs
* immediately when requested, using the settlement price and fund.
*/
///@{
/// Price at which force settlements of a black swanned asset will occur
price settlement_price;
/// Amount of collateral which is available for force settlement
share_type settlement_fund;
///@}
time_point_sec feed_expiration_time()const
{ return current_feed_publication_time + options.feed_lifetime_sec; }
bool feed_is_expired(time_point_sec current_time)const
{ return feed_expiration_time() <= current_time; }
void update_median_feeds(time_point_sec current_time);
};
struct by_feed_expiration;
typedef multi_index_container<
asset_bitasset_data_object,
indexed_by<
ordered_unique< tag<by_id>, member< object, object_id_type, &object::id > >,
ordered_non_unique< tag<by_feed_expiration>,
const_mem_fun< asset_bitasset_data_object, time_point_sec, &asset_bitasset_data_object::feed_expiration_time >
>
>
> asset_bitasset_data_object_multi_index_type;
typedef flat_index<asset_bitasset_data_object> asset_bitasset_data_index;
struct by_symbol;
struct by_type;
typedef multi_index_container<
asset_object,
indexed_by<
ordered_unique< tag<by_id>, member< object, object_id_type, &object::id > >,
ordered_unique< tag<by_symbol>, member<asset_object, string, &asset_object::symbol> >,
ordered_unique< tag<by_type>,
composite_key< asset_object,
const_mem_fun<asset_object, bool, &asset_object::is_market_issued>,
member< object, object_id_type, &object::id >
>
>
>
> asset_object_multi_index_type;
typedef generic_index<asset_object, asset_object_multi_index_type> asset_index;
} } // graphene::chain
FC_REFLECT_DERIVED( graphene::chain::asset_dynamic_data_object, (graphene::db::object),
(current_supply)(confidential_supply)(accumulated_fees)(fee_pool) )
FC_REFLECT_DERIVED( graphene::chain::asset_bitasset_data_object, (graphene::db::object),
(feeds)
(current_feed)
(current_feed_publication_time)
(options)
(force_settled_volume)
(is_prediction_market)
(settlement_price)
(settlement_fund)
)
FC_REFLECT_DERIVED( graphene::chain::asset_object, (graphene::db::object),
(symbol)
(precision)
(issuer)
(options)
(dynamic_asset_data_id)
(bitasset_data_id)
(buyback_account)
)