/*	EQEMu: Everquest Server Emulator
	Copyright (C) 2001-2002 EQEMu Development Team (http://eqemu.org)

	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; version 2 of the License.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY except by those people which sell it, which
	are required to give you total support for your newly bought product;
	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
*/

#include "../common/global_define.h"
#include "../common/loottable.h"
#include "../common/data_verification.h"

#include "client.h"
#include "entity.h"
#include "mob.h"
#include "npc.h"
#include "zonedb.h"
#include "global_loot_manager.h"
#include "../common/repositories/criteria/content_filter_criteria.h"
#include "quest_parser_collection.h"

#ifdef _WINDOWS
#define snprintf	_snprintf
#endif

// Queries the loottable: adds item & coin to the npc
void ZoneDatabase::AddLootTableToNPC(
	NPC *npc,
	uint32 loottable_id,
	ItemList *itemlist,
	uint32 *copper,
	uint32 *silver,
	uint32 *gold,
	uint32 *plat
)
{
	const bool is_global = (
		copper == nullptr &&
		silver == nullptr &&
		gold == nullptr &&
		plat == nullptr
	);
	if (!is_global) {
		*copper = 0;
		*silver = 0;
		*gold = 0;
		*plat = 0;
	}

	const auto *lts = database.GetLootTable(loottable_id);
	if (!lts) {
		return;
	}

	if (!content_service.DoesPassContentFiltering(lts->content_flags)) {
		return;
	}

	uint32 min_cash = lts->mincash;
	uint32 max_cash = lts->maxcash;
	if (min_cash > max_cash) {
		const uint32 t = min_cash;
		min_cash = max_cash;
		max_cash = t;
	}

	uint32 cash = 0;
	if (!is_global) {
		if (
			max_cash > 0 &&
			lts->avgcoin > 0 &&
			EQ::ValueWithin(lts->avgcoin, min_cash, max_cash)
		) {
			const float upper_chance  = static_cast<float>(lts->avgcoin - min_cash) / static_cast<float>(max_cash - min_cash);
			const float avg_cash_roll = static_cast<float>(zone->random.Real(0.0, 1.0));

			if (avg_cash_roll < upper_chance) {
				cash = zone->random.Int(lts->avgcoin, max_cash);
			} else {
				cash = zone->random.Int(min_cash, lts->avgcoin);
			}
		} else {
			cash = zone->random.Int(min_cash, max_cash);
		}
	}

	if (cash != 0) {
		*plat = cash / 1000;
		cash -= *plat * 1000;

		*gold = cash / 100;
		cash -= *gold * 100;

		*silver = cash / 10;
		cash -= *silver * 10;

		*copper = cash;
	}

	const uint32 global_loot_multiplier = RuleI(Zone, GlobalLootMultiplier);

	for (uint32 i = 0; i < lts->NumEntries; i++) {
		for (uint32 k = 1; k <= (lts->Entries[i].multiplier * global_loot_multiplier); k++) {
			const uint8 drop_limit   = lts->Entries[i].droplimit;
			const uint8 minimum_drop = lts->Entries[i].mindrop;

			//LootTable Entry probability
			const float probability = lts->Entries[i].probability;

			float drop_chance = 0.0f;
			if (EQ::ValueWithin(probability, 0.0f, 100.0f)) {
				drop_chance = static_cast<float>(zone->random.Real(0.0, 100.0));
			}

			if (probability != 0.0 && (probability == 100.0 || drop_chance <= probability)) {
				AddLootDropToNPC(npc, lts->Entries[i].lootdrop_id, itemlist, drop_limit, minimum_drop);
			}
		}
	}
}

// Called by AddLootTableToNPC
// maxdrops = size of the array npcd
void ZoneDatabase::AddLootDropToNPC(NPC *npc, uint32 lootdrop_id, ItemList *item_list, uint8 droplimit, uint8 mindrop)
{
	const auto *lds = GetLootDrop(lootdrop_id);
	if (
		!lds ||
		lds->NumEntries == 0 ||
		!content_service.DoesPassContentFiltering(lds->content_flags)
	) {
		return;
	}

	// if this lootdrop is droplimit=0 and mindrop 0, scan list once and return
	if (droplimit == 0 && mindrop == 0) {
		for (uint32 i = 0; i < lds->NumEntries; ++i) {
			const uint8 charges = lds->Entries[i].multiplier;
			for (int j = 0; j < charges; ++j) {
				if (
					zone->random.Real(0.0, 100.0) <= lds->Entries[i].chance &&
					npc->MeetsLootDropLevelRequirements(lds->Entries[i], true)
				) {
					const EQ::ItemData *database_item = GetItem(lds->Entries[i].item_id);
					npc->AddLootDrop(
						database_item,
						item_list,
						lds->Entries[i]
					);
				}
			}
		}
		return;
	}

	if (lds->NumEntries > 100 && droplimit == 0) {
		droplimit = 10;
	}

	if (droplimit < mindrop) {
		droplimit = mindrop;
	}

	float roll_t                   = 0.0f;
	float no_loot_prob             = 1.0f;
	bool  roll_table_chance_bypass = false;
	bool  active_item_list         = false;

	for (uint32 i = 0; i < lds->NumEntries; ++i) {
		const EQ::ItemData *db_item = GetItem(lds->Entries[i].item_id);
		if (db_item && npc->MeetsLootDropLevelRequirements(lds->Entries[i])) {
			roll_t += lds->Entries[i].chance;

			if (lds->Entries[i].chance >= 100) {
				roll_table_chance_bypass = true;
			} else {
				no_loot_prob *= (100 - lds->Entries[i].chance) / 100.0f;
			}

			active_item_list = true;
		}
	}

	if (!active_item_list) {
		return;
	}

	// This will pick one item per iteration until mindrop.
	// Don't let the compare against chance fool you.
	// The roll isn't 0-100, its 0-total and it picks the item, we're just
	// looping to find the lucky item, descremening otherwise. This is ok,
	// items with chance 60 are 6 times more likely than items chance 10.
	int drops = 0;

	for (int i = 0; i < droplimit; ++i) {
		if (drops < mindrop || roll_table_chance_bypass || (float) zone->random.Real(0.0, 1.0) >= no_loot_prob) {
			float       roll = (float) zone->random.Real(0.0, roll_t);
			for (uint32 j    = 0; j < lds->NumEntries; ++j) {
				const auto *db_item = GetItem(lds->Entries[j].item_id);
				if (db_item) {
					// if it doesn't meet the requirements do nothing
					if (!npc->MeetsLootDropLevelRequirements(lds->Entries[j])) {
						continue;
					}

					if (roll < lds->Entries[j].chance) {
						npc->AddLootDrop(
							db_item,
							item_list,
							lds->Entries[j]
						);
						drops++;

						uint8 charges = lds->Entries[i].multiplier;
						charges = EQ::ClampLower(charges, static_cast<uint8>(1));

						for (int k = 1; k < charges; ++k) {
							float c_roll = static_cast<float>(zone->random.Real(0.0, 100.0));
							if (c_roll <= lds->Entries[i].chance) {
								npc->AddLootDrop(
									db_item,
									item_list,
									lds->Entries[i]
								);
							}
						}

						j = lds->NumEntries;
						break;
					} else {
						roll -= lds->Entries[j].chance;
					}
				}
			}
		}
	}

	npc->UpdateEquipmentLight();
	// no wearchange associated with this function..so, this should not be needed
	//if (npc->UpdateActiveLightValue())
	//	npc->SendAppearancePacket(AppearanceType::Light, npc->GetActiveLightValue());
}

bool NPC::MeetsLootDropLevelRequirements(LootDropEntries_Struct loot_drop, bool verbose)
{
	if (loot_drop.npc_min_level > 0 && GetLevel() < loot_drop.npc_min_level) {
		if (verbose) {
			LogLootDetail(
				"NPC [{}] does not meet loot_drop level requirements (min_level) level [{}] current [{}] for item [{}]",
				GetCleanName(),
				loot_drop.npc_min_level,
				GetLevel(),
				database.CreateItemLink(loot_drop.item_id)
			);
		}
		return false;
	}

	if (loot_drop.npc_max_level > 0 && GetLevel() > loot_drop.npc_max_level) {
		if (verbose) {
			LogLootDetail(
				"NPC [{}] does not meet loot_drop level requirements (max_level) level [{}] current [{}] for item [{}]",
				GetCleanName(),
				loot_drop.npc_max_level,
				GetLevel(),
				database.CreateItemLink(loot_drop.item_id)
			);
		}
		return false;
	}

	return true;
}

LootDropEntries_Struct NPC::NewLootDropEntry()
{
	LootDropEntries_Struct loot_drop{};
	loot_drop.item_id           = 0;
	loot_drop.item_charges      = 1;
	loot_drop.equip_item        = 1;
	loot_drop.chance            = 0;
	loot_drop.trivial_min_level = 0;
	loot_drop.trivial_max_level = 0;
	loot_drop.npc_min_level     = 0;
	loot_drop.npc_max_level     = 0;
	loot_drop.multiplier        = 0;

	return loot_drop;
}

//if itemlist is null, just send wear changes
void NPC::AddLootDrop(
	const EQ::ItemData *item2,
	ItemList *itemlist,
	LootDropEntries_Struct loot_drop,
	bool wear_change,
	uint32 augment_one,
	uint32 augment_two,
	uint32 augment_three,
	uint32 augment_four,
	uint32 augment_five,
	uint32 augment_six
)
{
	if (!item2) {
		return;
	}

	if (!itemlist && !wear_change) {
		return;
	}

	auto item = new ServerLootItem_Struct;

	if (LogSys.log_settings[Logs::Loot].is_category_enabled == 1) {
		EQ::SayLinkEngine linker;
		linker.SetLinkType(EQ::saylink::SayLinkItemData);
		linker.SetItemData(item2);

		LogLoot(
			"NPC [{}] Item ({}) [{}] charges [{}] chance [{}] trivial min/max [{}/{}] npc min/max [{}/{}]",
			GetName(),
			item2->ID,
			linker.GenerateLink(),
			loot_drop.item_charges,
			loot_drop.chance,
			loot_drop.trivial_min_level,
			loot_drop.trivial_max_level,
			loot_drop.npc_min_level,
			loot_drop.npc_max_level
		);
	}

	EQApplicationPacket *outapp               = nullptr;
	WearChange_Struct   *p_wear_change_struct = nullptr;
	if (wear_change) {
		outapp               = new EQApplicationPacket(OP_WearChange, sizeof(WearChange_Struct));
		p_wear_change_struct = (WearChange_Struct *) outapp->pBuffer;
		p_wear_change_struct->spawn_id = GetID();
		p_wear_change_struct->material = 0;
	}

	item->item_id           = item2->ID;
	item->charges           = loot_drop.item_charges;
	item->aug_1             = augment_one;
	item->aug_2             = augment_two;
	item->aug_3             = augment_three;
	item->aug_4             = augment_four;
	item->aug_5             = augment_five;
	item->aug_6             = augment_six;
	item->attuned           = false;
	item->trivial_min_level = loot_drop.trivial_min_level;
	item->trivial_max_level = loot_drop.trivial_max_level;
	item->equip_slot        = EQ::invslot::SLOT_INVALID;

	// unsure if required to equip, YOLO for now
	if (item2->ItemType == EQ::item::ItemTypeBow) {
		SetBowEquipped(true);
	}

	if (item2->ItemType == EQ::item::ItemTypeArrow) {
		SetArrowEquipped(true);
	}

	bool found = false; // track if we found an empty slot we fit into

	int found_slot = INVALID_INDEX; // for multi-slot items

	auto *inst = database.CreateItem(
		item2->ID,
		loot_drop.item_charges,
		augment_one,
		augment_two,
		augment_three,
		augment_four,
		augment_five,
		augment_six
	);

	if (!inst) {
		return;
	}

	if (loot_drop.equip_item > 0) {
		uint8 equipment_slot = UINT8_MAX;
		const EQ::ItemData *compitem = nullptr;

		// Equip rules are as follows:
		// If the item has the NoPet flag set it will not be equipped.
		// An empty slot takes priority. The first empty one that an item can
		// fit into will be the one picked for the item.
		// AC is the primary choice for which item gets picked for a slot.
		// If AC is identical HP is considered next.
		// If an item can fit into multiple slots we'll pick the last one where
		// it is an improvement.

		if (!item2->NoPet) {
			for (
				int i = EQ::invslot::EQUIPMENT_BEGIN;
				!found && i <= EQ::invslot::EQUIPMENT_END;
				i++
			) {
				const uint32 slots = (1 << i);
				if (item2->Slots & slots) {
					if (equipment[i]) {
						compitem = database.GetItem(equipment[i]);
						if (
							item2->AC > compitem->AC ||
							(item2->AC == compitem->AC && item2->HP > compitem->HP)
						) {
							// item would be an upgrade
							// check if we're multi-slot, if yes then we have to keep
							// looking in case any of the other slots we can fit into are empty.
							if (item2->Slots != slots) {
								found_slot = i;
							} else {
								// Unequip old item
								auto *old_item = GetItem(i);

								old_item->equip_slot = EQ::invslot::SLOT_INVALID;

								equipment[i] = item2->ID;

								found_slot = i;
								found      = true;
							}
						}
					} else {
						equipment[i] = item2->ID;

						found_slot = i;
						found      = true;
					}
				}
			}
		}

		// Possible slot was found but not selected. Pick it now.
		if (!found && found_slot >= 0) {
			equipment[found_slot] = item2->ID;

			found = true;
		}

		uint32 equipment_material;
		if (
			item2->Material <= 0 ||
			(
				item2->Slots & (
					(1 << EQ::invslot::slotPrimary) |
					(1 << EQ::invslot::slotSecondary)
				)
			)
		) {
			equipment_material = Strings::ToUnsignedInt(&item2->IDFile[2]);
		} else {
			equipment_material = item2->Material;
		}

		if (found_slot == EQ::invslot::slotPrimary) {
			equipment_slot = EQ::textures::weaponPrimary;

			if (item2->Damage > 0) {
				SendAddPlayerState(PlayerState::PrimaryWeaponEquipped);

				if (!RuleB(Combat, ClassicNPCBackstab)) {
					SetFacestab(true);
				}
			}

			if (item2->IsType2HWeapon()) {
				SetTwoHanderEquipped(true);
			}
		} else if (
			found_slot == EQ::invslot::slotSecondary &&
			(
				GetOwner() ||
				(CanThisClassDualWield() && zone->random.Roll(NPC_DW_CHANCE)) ||
				item2->Damage == 0
			) &&
			(
				item2->IsType1HWeapon() ||
				item2->ItemType == EQ::item::ItemTypeShield ||
				item2->ItemType == EQ::item::ItemTypeLight
			)
		) {
			equipment_slot = EQ::textures::weaponSecondary;

			if (item2->Damage > 0) {
				SendAddPlayerState(PlayerState::SecondaryWeaponEquipped);
			}
		} else if (found_slot == EQ::invslot::slotHead) {
			equipment_slot = EQ::textures::armorHead;
		} else if (found_slot == EQ::invslot::slotChest) {
			equipment_slot = EQ::textures::armorChest;
		} else if (found_slot == EQ::invslot::slotArms) {
			equipment_slot = EQ::textures::armorArms;
		} else if (EQ::ValueWithin(found_slot, EQ::invslot::slotWrist1, EQ::invslot::slotWrist2)) {
			equipment_slot = EQ::textures::armorWrist;
		} else if (found_slot == EQ::invslot::slotHands) {
			equipment_slot = EQ::textures::armorHands;
		} else if (found_slot == EQ::invslot::slotLegs) {
			equipment_slot = EQ::textures::armorLegs;
		} else if (found_slot == EQ::invslot::slotFeet) {
			equipment_slot = EQ::textures::armorFeet;
		}

		if (equipment_slot != UINT8_MAX) {
			if (wear_change) {
				p_wear_change_struct->wear_slot_id = equipment_slot;
				p_wear_change_struct->material     = equipment_material;
			}
		}

		if (found) {
			item->equip_slot = found_slot;
		}
	}

	if (itemlist) {
		if (found_slot != INVALID_INDEX) {
			GetInv().PutItem(found_slot, *inst);
		}

		if (parse->HasQuestSub(GetNPCTypeID(), EVENT_LOOT_ADDED)) {
			std::vector<std::any> args = { inst };
			parse->EventNPC(EVENT_LOOT_ADDED, this, nullptr, "", 0, &args);
		}

		itemlist->push_back(item);
	} else {
		safe_delete(item);
	}

	if (found) {
		CalcBonuses();
	}

	if (IsRecordLootStats()) {
		m_rolled_items.emplace_back(item->item_id);
	}

	if (wear_change && outapp) {
		entity_list.QueueClients(this, outapp);
		safe_delete(outapp);
	}

	UpdateEquipmentLight();

	if (UpdateActiveLight()) {
		SendAppearancePacket(AppearanceType::Light, GetActiveLightType());
	}
}

void NPC::AddItem(const EQ::ItemData *item, uint16 charges, bool equip_item)
{
	auto loot_drop_entry = NPC::NewLootDropEntry();

	loot_drop_entry.equip_item   = static_cast<uint8>(equip_item ? 1 : 0);
	loot_drop_entry.item_charges = charges;

	AddLootDrop(item, &itemlist, loot_drop_entry, true);
}

void NPC::AddItem(
	uint32 item_id,
	uint16 charges,
	bool equip_item,
	uint32 augment_one,
	uint32 augment_two,
	uint32 augment_three,
	uint32 augment_four,
	uint32 augment_five,
	uint32 augment_six
)
{
	const auto *item = database.GetItem(item_id);
	if (!item) {
		return;
	}

	auto loot_drop_entry = NPC::NewLootDropEntry();

	loot_drop_entry.equip_item   = static_cast<uint8>(equip_item ? 1 : 0);
	loot_drop_entry.item_charges = charges;

	AddLootDrop(
		item,
		&itemlist,
		loot_drop_entry,
		true,
		augment_one,
		augment_two,
		augment_three,
		augment_four,
		augment_five,
		augment_six
	);
}

void NPC::AddLootTable()
{
	if (npctype_id != 0) { // check if it's a GM spawn
		database.AddLootTableToNPC(this, loottable_id, &itemlist, &copper, &silver, &gold, &platinum);
	}
}

void NPC::AddLootTable(uint32 loottable_id)
{
	if (npctype_id != 0) { // check if it's a GM spawn
		database.AddLootTableToNPC(this, loottable_id, &itemlist, &copper, &silver, &gold, &platinum);
	}
}

void NPC::CheckGlobalLootTables()
{
	auto tables = zone->GetGlobalLootTables(this);

	for (auto &id : tables)
		database.AddLootTableToNPC(this, id, &itemlist, nullptr, nullptr, nullptr, nullptr);
}

void ZoneDatabase::LoadGlobalLoot()
{
	auto query = fmt::format(
		SQL
		(
			SELECT
			  id,
			  loottable_id,
			  description,
			  min_level,
			  max_level,
			  rare,
			  raid,
			  race,
			  class,
			  bodytype,
			  zone,
			  hot_zone
			FROM
			  global_loot
			WHERE
			  enabled = 1
			  {}
		),
		ContentFilterCriteria::apply()
	);

	auto results = QueryDatabase(query);
	if (!results.Success() || results.RowCount() == 0) {
		return;
	}

	LogInfo("Loaded [{}] global loot entries", Strings::Commify(results.RowCount()));

	// we might need this, lets not keep doing it in a loop
	auto      zoneid = std::to_string(zone->GetZoneID());
	for (auto row    = results.begin(); row != results.end(); ++row) {
		// checking zone limits
		if (row[10]) {
			auto zones = Strings::Split(row[10], '|');

			auto it = std::find(zones.begin(), zones.end(), zoneid);
			if (it == zones.end()) {  // not in here, skip
				continue;
			}
		}

		GlobalLootEntry e(Strings::ToInt(row[0]), Strings::ToInt(row[1]), row[2] ? row[2] : "");

		auto min_level = Strings::ToInt(row[3]);
		if (min_level) {
			e.AddRule(GlobalLoot::RuleTypes::LevelMin, min_level);
		}

		auto max_level = Strings::ToInt(row[4]);
		if (max_level) {
			e.AddRule(GlobalLoot::RuleTypes::LevelMax, max_level);
		}

		// null is not used
		if (row[5]) {
			e.AddRule(GlobalLoot::RuleTypes::Rare, Strings::ToInt(row[5]));
		}

		// null is not used
		if (row[6]) {
			e.AddRule(GlobalLoot::RuleTypes::Raid, Strings::ToInt(row[6]));
		}

		if (row[7]) {
			auto races = Strings::Split(row[7], '|');

			for (auto &r : races)
				e.AddRule(GlobalLoot::RuleTypes::Race, Strings::ToInt(r));
		}

		if (row[8]) {
			auto classes = Strings::Split(row[8], '|');

			for (auto &c : classes)
				e.AddRule(GlobalLoot::RuleTypes::Class, Strings::ToInt(c));
		}

		if (row[9]) {
			auto bodytypes = Strings::Split(row[9], '|');

			for (auto &b : bodytypes)
				e.AddRule(GlobalLoot::RuleTypes::BodyType, Strings::ToInt(b));
		}

		// null is not used
		if (row[11]) {
			e.AddRule(GlobalLoot::RuleTypes::HotZone, Strings::ToInt(row[11]));
		}

		zone->AddGlobalLootEntry(e);
	}
}