/**
 * MaNGOS is a full featured server for World of Warcraft, supporting
 * the following clients: 1.12.x, 2.4.3, 3.3.5a, 4.3.4a and 5.4.8
 *
 * Copyright (C) 2005-2017  MaNGOS project <https://getmangos.eu>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * World of Warcraft, and all World of Warcraft or Warcraft art, images,
 * and lore are copyrighted by Blizzard Entertainment, Inc.
 */

#include "ItemEnchantmentMgr.h"
#include "Database/DatabaseEnv.h"
#include "Log.h"
#include "ObjectMgr.h"
#include "ProgressBar.h"
#include "Util.h"

#include <list>
#include <vector>

struct EnchStoreItem
{
    uint32  ench;
    float   chance;

    EnchStoreItem()
        : ench(0), chance(0) {}

    EnchStoreItem(uint32 _ench, float _chance)
        : ench(_ench), chance(_chance) {}
};

typedef std::vector<EnchStoreItem> EnchStoreList;
typedef UNORDERED_MAP<uint32, EnchStoreList> EnchantmentStore;

static EnchantmentStore RandomItemEnch;

void LoadRandomEnchantmentsTable()
{
    RandomItemEnch.clear();                                 // for reload case

    uint32 count = 0;
    QueryResult* result = WorldDatabase.Query("SELECT entry, ench, chance FROM item_enchantment_template");

    if (result)
    {
        BarGoLink bar(result->GetRowCount());

        do
        {
            Field* fields = result->Fetch();
            bar.step();

            uint32 entry = fields[0].GetUInt32();
            uint32 ench = fields[1].GetUInt32();
            float chance = fields[2].GetFloat();

            if (chance > 0.000001f && chance <= 100.0f)
                { RandomItemEnch[entry].push_back(EnchStoreItem(ench, chance)); }

            ++count;
        }
        while (result->NextRow());

        delete result;

        sLog.outString(">> Loaded %u Item Enchantment definitions", count);
    }
    else
        sLog.outErrorDb(">> Loaded 0 Item Enchantment definitions. DB table `item_enchantment_template` is empty.");

    sLog.outString();
}

uint32 GetItemEnchantMod(uint32 entry)
{
    if (!entry) { return 0; }

    EnchantmentStore::const_iterator tab = RandomItemEnch.find(entry);

    if (tab == RandomItemEnch.end())
    {
        sLog.outErrorDb("Item RandomProperty id #%u used in `item_template` but it doesn't have records in `item_enchantment_template` table.", entry);
        return 0;
    }

    double dRoll = rand_chance();
    float fCount = 0;

    const EnchStoreList &enchantList = tab->second;
    for (EnchStoreList::const_iterator ench_iter = enchantList.begin(); ench_iter != enchantList.end(); ++ench_iter)
    {
        fCount += ench_iter->chance;

        if (fCount > dRoll) { return ench_iter->ench; }
    }

    // we could get here only if sum of all enchantment chances is lower than 100%
    dRoll = (irand(0, (int)floor(fCount * 100) + 1)) / 100;
    fCount = 0;

    for (EnchStoreList::const_iterator ench_iter = enchantList.begin(); ench_iter != enchantList.end(); ++ench_iter)
    {
        fCount += ench_iter->chance;

        if (fCount > dRoll) { return ench_iter->ench; }
    }

    return 0;
}