// Copyright (c) Athena Dev Teams - Licensed under GNU GPL
// For more information, see LICENCE in the main folder

#include "../common/cbasetypes.h"
#include "../common/db.h"  // ARR_FIND
#include "../common/showmsg.h"  // ShowWarning
#include "../common/socket.h"  // RBUF*
#include "../common/strlib.h"  // safestrncpy
#include "atcommand.h"  // msg_txt
#include "battle.h"  // battle_config.*
#include "buyingstore.h"  // struct s_buyingstore
#include "clif.h"  // clif_buyingstore_*
#include "log.h"  // log_pick_pc, log_zeny
#include "pc.h"  // struct map_session_data


/// constants (client-side restrictions)
#define BUYINGSTORE_MAX_PRICE 99990000
#define BUYINGSTORE_MAX_AMOUNT 9999


/// failure constants for clif functions
enum e_buyingstore_failure {
    BUYINGSTORE_CREATE               = 1,  // "Failed to open buying store."
    BUYINGSTORE_CREATE_OVERWEIGHT    = 2,  // "Total amount of then possessed items exceeds the weight limit by %d. Please re-enter."
    BUYINGSTORE_TRADE_BUYER_ZENY     = 3,  // "All items within the buy limit were purchased."
    BUYINGSTORE_TRADE_BUYER_NO_ITEMS = 4,  // "All items were purchased."
    BUYINGSTORE_TRADE_SELLER_FAILED  = 5,  // "The deal has failed."
    BUYINGSTORE_TRADE_SELLER_COUNT   = 6,  // "The trade failed, because the entered amount of item %s is higher, than the buyer is willing to buy."
    BUYINGSTORE_TRADE_SELLER_ZENY    = 7,  // "The trade failed, because the buyer is lacking required balance."
    BUYINGSTORE_CREATE_NO_INFO       = 8,  // "No sale (purchase) information available."
};


static unsigned int buyingstore_nextid = 0;
static const short buyingstore_blankslots[MAX_SLOTS] = { 0 };  // used when checking whether or not an item's card slots are blank


/// Returns unique buying store id
static unsigned int buyingstore_getuid(void)
{
    return buyingstore_nextid++;
}


bool buyingstore_setup(struct map_session_data *sd, unsigned char slots)
{
    if (!battle_config.feature_buying_store || sd->state.vending || sd->state.buyingstore || sd->state.trading || slots == 0) {
        return false;
    }

    if (sd->sc.data[SC_NOCHAT] && (sd->sc.data[SC_NOCHAT]->val1&MANNER_NOROOM)) {
        // custom: mute limitation
        return false;
    }

    if (map[sd->bl.m].flag.novending) {
        // custom: no vending maps
        clif_displaymessage(sd->fd, msg_txt(276)); // "You can't open a shop on this map"
        return false;
    }

    if (map_getcell(sd->bl.m, sd->bl.x, sd->bl.y, CELL_CHKNOVENDING)) {
        // custom: no vending cells
        clif_displaymessage(sd->fd, msg_txt(204)); // "You can't open a shop on this cell."
        return false;
    }

    if (slots > MAX_BUYINGSTORE_SLOTS) {
        ShowWarning("buyingstore_setup: Requested %d slots, but server supports only %d slots.\n", (int)slots, MAX_BUYINGSTORE_SLOTS);
        slots = MAX_BUYINGSTORE_SLOTS;
    }

    sd->buyingstore.slots = slots;
    clif_buyingstore_open(sd);

    return true;
}


void buyingstore_create(struct map_session_data *sd, int zenylimit, unsigned char result, const char *storename, const uint8 *itemlist, unsigned int count)
{
    unsigned int i, weight, listidx;
    struct item_data *id;

    if (!result || count == 0) {
        // canceled, or no items
        return;
    }

    if (!battle_config.feature_buying_store || pc_istrading(sd) || sd->buyingstore.slots == 0 || count > sd->buyingstore.slots || zenylimit <= 0 || zenylimit > sd->status.zeny || !storename[0]) {
        // disabled or invalid input
        sd->buyingstore.slots = 0;
        clif_buyingstore_open_failed(sd, BUYINGSTORE_CREATE, 0);
        return;
    }

    if (!pc_can_give_items(sd)) {
        // custom: GM is not allowed to buy (give zeny)
        sd->buyingstore.slots = 0;
        clif_displaymessage(sd->fd, msg_txt(246));
        clif_buyingstore_open_failed(sd, BUYINGSTORE_CREATE, 0);
        return;
    }

    if (sd->sc.data[SC_NOCHAT] && (sd->sc.data[SC_NOCHAT]->val1&MANNER_NOROOM)) {
        // custom: mute limitation
        return;
    }

    if (map[sd->bl.m].flag.novending) {
        // custom: no vending maps
        clif_displaymessage(sd->fd, msg_txt(276)); // "You can't open a shop on this map"
        return;
    }

    if (map_getcell(sd->bl.m, sd->bl.x, sd->bl.y, CELL_CHKNOVENDING)) {
        // custom: no vending cells
        clif_displaymessage(sd->fd, msg_txt(204)); // "You can't open a shop on this cell."
        return;
    }

    weight = sd->weight;

    // check item list
    for (i = 0; i < count; i++) {
        // itemlist: <name id>.W <amount>.W <price>.L
        unsigned short nameid, amount;
        int price, idx;

        nameid = RBUFW(itemlist,i*8+0);
        amount = RBUFW(itemlist,i*8+2);
        price  = RBUFL(itemlist,i*8+4);

        if ((id = itemdb_exists(nameid)) == NULL || amount == 0) {
            // invalid input
            break;
        }

        if (price <= 0 || price > BUYINGSTORE_MAX_PRICE) {
            // invalid price: unlike vending, items cannot be bought at 0 Zeny
            break;
        }

        if (!id->flag.buyingstore || !itemdb_cantrade_sub(id, pc_get_group_level(sd), pc_get_group_level(sd)) || (idx = pc_search_inventory(sd, nameid)) == -1) {
            // restrictions: allowed, no character-bound items and at least one must be owned
            break;
        }

        if (sd->status.inventory[idx].amount+amount > BUYINGSTORE_MAX_AMOUNT) {
            // too many items of same kind
            break;
        }

        if (i) {
            // duplicate check. as the client does this too, only malicious intent should be caught here
            ARR_FIND(0, i, listidx, sd->buyingstore.items[listidx].nameid == nameid);
            if (listidx != i) {
                // duplicate
                ShowWarning("buyingstore_create: Found duplicate item on buying list (nameid=%hu, amount=%hu, account_id=%d, char_id=%d).\n", nameid, amount, sd->status.account_id, sd->status.char_id);
                break;
            }
        }

        weight+= id->weight*amount;
        sd->buyingstore.items[i].nameid = nameid;
        sd->buyingstore.items[i].amount = amount;
        sd->buyingstore.items[i].price  = price;
    }

    if (i != count) {
        // invalid item/amount/price
        sd->buyingstore.slots = 0;
        clif_buyingstore_open_failed(sd, BUYINGSTORE_CREATE, 0);
        return;
    }

    if ((sd->max_weight*90)/100 < weight) {
        // not able to carry all wanted items without getting overweight (90%)
        sd->buyingstore.slots = 0;
        clif_buyingstore_open_failed(sd, BUYINGSTORE_CREATE_OVERWEIGHT, weight);
        return;
    }

    // success
    sd->state.buyingstore = true;
    sd->buyer_id = buyingstore_getuid();
    sd->buyingstore.zenylimit = zenylimit;
    sd->buyingstore.slots = i;  // store actual amount of items
    safestrncpy(sd->message, storename, sizeof(sd->message));
    clif_buyingstore_myitemlist(sd);
    clif_buyingstore_entry(sd);
}


void buyingstore_close(struct map_session_data *sd)
{
    if (sd->state.buyingstore) {
        // invalidate data
        sd->state.buyingstore = false;
        memset(&sd->buyingstore, 0, sizeof(sd->buyingstore));

        // notify other players
        clif_buyingstore_disappear_entry(sd);
    }
}


void buyingstore_open(struct map_session_data *sd, int account_id)
{
    struct map_session_data *pl_sd;

    if (!battle_config.feature_buying_store || pc_istrading(sd)) {
        // not allowed to sell
        return;
    }

    if (!pc_can_give_items(sd)) {
        // custom: GM is not allowed to sell
        clif_displaymessage(sd->fd, msg_txt(246));
        return;
    }

    if ((pl_sd = map_id2sd(account_id)) == NULL || !pl_sd->state.buyingstore) {
        // not online or not buying
        return;
    }

    if (!searchstore_queryremote(sd, account_id) && (sd->bl.m != pl_sd->bl.m || !check_distance_bl(&sd->bl, &pl_sd->bl, AREA_SIZE))) {
        // out of view range
        return;
    }

    // success
    clif_buyingstore_itemlist(sd, pl_sd);
}


void buyingstore_trade(struct map_session_data *sd, int account_id, unsigned int buyer_id, const uint8 *itemlist, unsigned int count)
{
    int zeny = 0;
    unsigned int i, weight, listidx, k;
    struct map_session_data *pl_sd;

    if (count == 0) {
        // nothing to do
        return;
    }

    if (!battle_config.feature_buying_store || pc_istrading(sd)) {
        // not allowed to sell
        clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, 0);
        return;
    }

    if (!pc_can_give_items(sd)) {
        // custom: GM is not allowed to sell
        clif_displaymessage(sd->fd, msg_txt(246));
        clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, 0);
        return;
    }

    if ((pl_sd = map_id2sd(account_id)) == NULL || !pl_sd->state.buyingstore || pl_sd->buyer_id != buyer_id) {
        // not online, not buying or not same store
        clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, 0);
        return;
    }

    if (!searchstore_queryremote(sd, account_id) && (sd->bl.m != pl_sd->bl.m || !check_distance_bl(&sd->bl, &pl_sd->bl, AREA_SIZE))) {
        // out of view range
        clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, 0);
        return;
    }

    searchstore_clearremote(sd);

    if (pl_sd->status.zeny < pl_sd->buyingstore.zenylimit) {
        // buyer lost zeny in the mean time? fix the limit
        pl_sd->buyingstore.zenylimit = pl_sd->status.zeny;
    }
    weight = pl_sd->weight;

    // check item list
    for (i = 0; i < count; i++) {
        // itemlist: <index>.W <name id>.W <amount>.W
        unsigned short nameid, amount;
        int index;

        index  = RBUFW(itemlist,i*6+0)-2;
        nameid = RBUFW(itemlist,i*6+2);
        amount = RBUFW(itemlist,i*6+4);

        if (i) {
            // duplicate check. as the client does this too, only malicious intent should be caught here
            ARR_FIND(0, i, k, RBUFW(itemlist,k*6+0)-2 == index);
            if (k != i) {
                // duplicate
                ShowWarning("buyingstore_trade: Found duplicate item on selling list (prevnameid=%hu, prevamount=%hu, nameid=%hu, amount=%hu, account_id=%d, char_id=%d).\n",
                            RBUFW(itemlist,k*6+2), RBUFW(itemlist,k*6+4), nameid, amount, sd->status.account_id, sd->status.char_id);
                clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, nameid);
                return;
            }
        }

        if (index < 0 || index >= ARRAYLENGTH(sd->status.inventory) || sd->inventory_data[index] == NULL || sd->status.inventory[index].nameid != nameid || sd->status.inventory[index].amount < amount) {
            // invalid input
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, nameid);
            return;
        }

        if (sd->status.inventory[index].expire_time || !itemdb_cantrade(&sd->status.inventory[index], pc_get_group_level(sd), pc_get_group_level(pl_sd)) || memcmp(sd->status.inventory[index].card, buyingstore_blankslots, sizeof(buyingstore_blankslots))) {
            // non-tradable item
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, nameid);
            return;
        }

        ARR_FIND(0, pl_sd->buyingstore.slots, listidx, pl_sd->buyingstore.items[listidx].nameid == nameid);
        if (listidx == pl_sd->buyingstore.slots || pl_sd->buyingstore.items[listidx].amount == 0) {
            // there is no such item or the buyer has already bought all of them
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, nameid);
            return;
        }

        if (pl_sd->buyingstore.items[listidx].amount < amount) {
            // buyer does not need that much of the item
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_COUNT, nameid);
            return;
        }

        if (pc_checkadditem(pl_sd, nameid, amount) == ADDITEM_OVERAMOUNT) {
            // buyer does not have enough space for this item
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, nameid);
            return;
        }

        if (amount*(unsigned int)sd->inventory_data[index]->weight > pl_sd->max_weight-weight) {
            // normally this is not supposed to happen, as the total weight is
            // checked upon creation, but the buyer could have gained items
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_FAILED, nameid);
            return;
        }
        weight+= amount*sd->inventory_data[index]->weight;

        if (amount*pl_sd->buyingstore.items[listidx].price > pl_sd->buyingstore.zenylimit-zeny) {
            // buyer does not have enough zeny
            clif_buyingstore_trade_failed_seller(sd, BUYINGSTORE_TRADE_SELLER_ZENY, nameid);
            return;
        }
        zeny+= amount*pl_sd->buyingstore.items[listidx].price;
    }

    // process item list
    for (i = 0; i < count; i++) {
        // itemlist: <index>.W <name id>.W <amount>.W
        unsigned short nameid, amount;
        int index;

        index  = RBUFW(itemlist,i*6+0)-2;
        nameid = RBUFW(itemlist,i*6+2);
        amount = RBUFW(itemlist,i*6+4);

        ARR_FIND(0, pl_sd->buyingstore.slots, listidx, pl_sd->buyingstore.items[listidx].nameid == nameid);
        zeny = amount*pl_sd->buyingstore.items[listidx].price;

        // move item
        pc_additem(pl_sd, &sd->status.inventory[index], amount, LOG_TYPE_BUYING_STORE);
        pc_delitem(sd, index, amount, 1, 0, LOG_TYPE_BUYING_STORE);
        pl_sd->buyingstore.items[listidx].amount-= amount;

        // pay up
        pc_payzeny(pl_sd, zeny, LOG_TYPE_BUYING_STORE, sd);
        pc_getzeny(sd, zeny, LOG_TYPE_BUYING_STORE, pl_sd);
        pl_sd->buyingstore.zenylimit-= zeny;

        // notify clients
        clif_buyingstore_delete_item(sd, index, amount, pl_sd->buyingstore.items[listidx].price);
        clif_buyingstore_update_item(pl_sd, nameid, amount);
    }

    // check whether or not there is still something to buy
    ARR_FIND(0, pl_sd->buyingstore.slots, i, pl_sd->buyingstore.items[i].amount != 0);
    if (i == pl_sd->buyingstore.slots) {
        // everything was bought
        clif_buyingstore_trade_failed_buyer(pl_sd, BUYINGSTORE_TRADE_BUYER_NO_ITEMS);
    } else if (pl_sd->buyingstore.zenylimit == 0) {
        // zeny limit reached
        clif_buyingstore_trade_failed_buyer(pl_sd, BUYINGSTORE_TRADE_BUYER_ZENY);
    } else {
        // continue buying
        return;
    }

    // cannot continue buying
    buyingstore_close(pl_sd);

    // remove auto-trader
    if (pl_sd->state.autotrade) {
        map_quit(pl_sd);
    }
}


/// Checks if an item is being bought in given player's buying store.
bool buyingstore_search(struct map_session_data *sd, unsigned short nameid)
{
    unsigned int i;

    if (!sd->state.buyingstore) {
        // not buying
        return false;
    }

    ARR_FIND(0, sd->buyingstore.slots, i, sd->buyingstore.items[i].nameid == nameid && sd->buyingstore.items[i].amount);
    if (i == sd->buyingstore.slots) {
        // not found
        return false;
    }

    return true;
}


/// Searches for all items in a buyingstore, that match given ids, price and possible cards.
/// @return Whether or not the search should be continued.
bool buyingstore_searchall(struct map_session_data *sd, const struct s_search_store_search *s)
{
    unsigned int i, idx;
    struct s_buyingstore_item *it;

    if (!sd->state.buyingstore) {
        // not buying
        return true;
    }

    for (idx = 0; idx < s->item_count; idx++) {
        ARR_FIND(0, sd->buyingstore.slots, i, sd->buyingstore.items[i].nameid == s->itemlist[idx] && sd->buyingstore.items[i].amount);
        if (i == sd->buyingstore.slots) {
            // not found
            continue;
        }
        it = &sd->buyingstore.items[i];

        if (s->min_price && s->min_price > (unsigned int)it->price) {
            // too low price
            continue;
        }

        if (s->max_price && s->max_price < (unsigned int)it->price) {
            // too high price
            continue;
        }

        if (s->card_count) {
            // ignore cards, as there cannot be any
            ;
        }

        if (!searchstore_result(s->search_sd, sd->buyer_id, sd->status.account_id, sd->message, it->nameid, it->amount, it->price, buyingstore_blankslots, 0)) {
            // result set full
            return false;
        }
    }

    return true;
}