//------------------------------------------------------------------------------
/*
    Copyright (c) 2011-2013, OpenCoin, Inc.
*/
//==============================================================================

#ifndef RIPPLE_PATHSTATE_H
#define RIPPLE_PATHSTATE_H

// account id, currency id, issuer id :: node
typedef boost::tuple <uint160, uint160, uint160> aciSource;
typedef boost::unordered_map <aciSource, unsigned int>                   curIssuerNode;  // Map of currency, issuer to node index.
typedef boost::unordered_map <aciSource, unsigned int>::const_iterator   curIssuerNodeConstIterator;

extern std::size_t hash_value (const aciSource& asValue);

// Holds a path state under incremental application.
class PathState
{
public:
    class Node
    {
    public:
        bool operator == (Node const& pnOther) const;

        Json::Value                     getJson () const;

    public:
        uint16                          uFlags;             // --> From path.

        uint160                         uAccountID;         // --> Accounts: Recieving/sending account.
        uint160                         uCurrencyID;        // --> Accounts: Receive and send, Offers: send.
        // --- For offer's next has currency out.
        uint160                         uIssuerID;          // --> Currency's issuer

        STAmount                        saTransferRate;     // Transfer rate for uIssuerID.

        // Computed by Reverse.
        STAmount                        saRevRedeem;        // <-- Amount to redeem to next.
        STAmount                        saRevIssue;         // <-- Amount to issue to next limited by credit and outstanding IOUs.
        //     Issue isn't used by offers.
        STAmount                        saRevDeliver;       // <-- Amount to deliver to next regardless of fee.

        // Computed by forward.
        STAmount                        saFwdRedeem;        // <-- Amount node will redeem to next.
        STAmount                        saFwdIssue;         // <-- Amount node will issue to next.
        //     Issue isn't used by offers.
        STAmount                        saFwdDeliver;       // <-- Amount to deliver to next regardless of fee.

        // For offers:

        STAmount                        saRateMax;

        // Directory
        uint256                         uDirectTip;         // Current directory.
        uint256                         uDirectEnd;         // Next order book.
        bool                            bDirectAdvance;     // Need to advance directory.
        SLE::pointer                    sleDirectDir;
        STAmount                        saOfrRate;          // For correct ratio.

        // PaymentNode
        bool                            bEntryAdvance;      // Need to advance entry.
        unsigned int                    uEntry;
        uint256                         uOfferIndex;
        SLE::pointer                    sleOffer;
        uint160                         uOfrOwnerID;
        bool                            bFundsDirty;        // Need to refresh saOfferFunds, saTakerPays, & saTakerGets.
        STAmount                        saOfferFunds;
        STAmount                        saTakerPays;
        STAmount                        saTakerGets;

    };
public:
    typedef boost::shared_ptr<PathState>        pointer;
    typedef const boost::shared_ptr<PathState>& ref;

public:
    PathState*  setIndex (const int iIndex)
    {
        mIndex  = iIndex;

        return this;
    }

    int getIndex ()
    {
        return mIndex;
    };

    PathState (
        const STAmount&         saSend,
        const STAmount&         saSendMax)
        : saInReq (saSendMax)
        , saOutReq (saSend)
    {
    }

    PathState (const PathState& psSrc,
               bool bUnused)
        : saInReq (psSrc.saInReq)
        , saOutReq (psSrc.saOutReq)
    {
    }

    void setExpanded (
        const LedgerEntrySet&   lesSource,
        const STPath&           spSourcePath,
        const uint160&          uReceiverID,
        const uint160&          uSenderID
    );

    void setCanonical (
        const PathState&        psExpanded
    );

    Json::Value getJson () const;

#if 0
    static PathState::pointer createCanonical (
        PathState& ref       pspExpanded
    )
    {
        PathState::pointer  pspNew  = boost::make_shared<PathState> (pspExpanded->saOutAct, pspExpanded->saInAct);

        pspNew->setCanonical (pspExpanded);

        return pspNew;
    }
#endif
    static bool lessPriority (PathState& lhs, PathState& rhs);

public:
    TER                         terStatus;
    std::vector<Node>    vpnNodes;

    // When processing, don't want to complicate directory walking with deletion.
    std::vector<uint256>        vUnfundedBecame;    // Offers that became unfunded or were completely consumed.

    // First time scanning foward, as part of path contruction, a funding source was mentioned for accounts. Source may only be
    // used there.
    curIssuerNode               umForward;          // Map of currency, issuer to node index.

    // First time working in reverse a funding source was used.
    // Source may only be used there if not mentioned by an account.
    curIssuerNode               umReverse;          // Map of currency, issuer to node index.

    LedgerEntrySet              lesEntries;

    int                         mIndex;             // Index/rank amoung siblings.
    uint64                      uQuality;           // 0 = no quality/liquity left.
    const STAmount&             saInReq;            // --> Max amount to spend by sender.
    STAmount                    saInAct;            // --> Amount spent by sender so far.
    STAmount                    saInPass;           // <-- Amount spent by sender.
    const STAmount&             saOutReq;           // --> Amount to send.
    STAmount                    saOutAct;           // --> Amount actually sent so far.
    STAmount                    saOutPass;          // <-- Amount actually sent.
    bool                        bConsumed;          // If true, use consumes full liquidity. False, may or may not.

private:
    TER pushNode (const int iType, const uint160& uAccountID, const uint160& uCurrencyID, const uint160& uIssuerID);
    TER pushImply (const uint160& uAccountID, const uint160& uCurrencyID, const uint160& uIssuerID);
};

#endif