/**
 * Copyright (c) 2026 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#pragma once
#include "script/scriptcontext.h"
#include "item/inventory.h"
#include "item/backpack.h"

int moduleInventoryItemExists(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Expect inventory pointer and item ID
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventoryItemExists: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventoryItemExists: Expected item ID as second argument");
    return 0;
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  itemid_t item = (itemid_t)lua_tointeger(L, 2);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  
  // Error if item is ITEM_ID_NULL
  if(item == ITEM_ID_NULL) {
    luaL_error(L, "inventoryItemExists: Item ID cannot be ITEM_ID_NULL");
    return 0;
  }

  bool_t hasItem = inventoryItemExists(inventory, item);
  lua_pushboolean(L, hasItem);
  return 1;
}

int moduleInventorySet(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer, item ID and quantity (uint8_t)
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventorySet: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventorySet: Expected item ID as second argument");
    return 0;
  }

  if(!lua_isinteger(L, 3)) {
    luaL_error(L, "inventorySet: Expected quantity as third argument");
    return 0;
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  itemid_t item = (itemid_t)lua_tointeger(L, 2);
  uint8_t quantity = (uint8_t)lua_tointeger(L, 3);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  inventorySet(inventory, item, quantity);
  return 0;
}

int moduleInventoryAdd(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer, item ID and quantity (uint8_t)
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventoryAdd: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventoryAdd: Expected item ID as second argument");
    return 0;
  }

  if(!lua_isinteger(L, 3)) {
    luaL_error(L, "inventoryAdd: Expected quantity as third argument");
    return 0;
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  itemid_t item = (itemid_t)lua_tointeger(L, 2);
  uint8_t quantity = (uint8_t)lua_tointeger(L, 3);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  inventoryAdd(inventory, item, quantity);
  return 0;
}

int moduleInventoryRemove(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer and item ID
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventoryRemove: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventoryRemove: Expected item ID as second argument");
    return 0;
  }
  
  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  itemid_t item = (itemid_t)lua_tointeger(L, 2);
  assertNotNull(inventory, "Inventory pointer cannot be NULL.");

  // if there is a third argument (quantity), then we are actually doing a
  // partial removal.
  if(lua_gettop(L) >= 3) {
    if(!lua_isinteger(L, 3)) {
      luaL_error(L, "inventoryRemove: Expected quantity as third argument");
      return 0;
    }
    uint8_t amount = (uint8_t)lua_tointeger(L, 3);
    uint8_t currentQuantity = inventoryGetCount(inventory, item);
    if(amount >= currentQuantity) {
      // Remove entire stack
      inventoryRemove(inventory, item);
      return 0;
    }
    
    // Set new quantity
    inventorySet(inventory, item, currentQuantity - amount);
    return 0;
  }

  inventoryRemove(inventory, item);
  return 0;
}

int moduleInventoryGetCount(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer and item ID
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventoryGetCount: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventoryGetCount: Expected item ID as second argument");
    return 0;
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  itemid_t item = (itemid_t)lua_tointeger(L, 2);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  
  uint8_t count = inventoryGetCount(inventory, item);
  lua_pushinteger(L, count);
  return 1;
}

int moduleInventoryIsFull(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventoryIsFull: Expected inventory pointer as first argument");
    return 0;
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  
  bool_t isFull = inventoryIsFull(inventory);
  lua_pushboolean(L, isFull);
  return 1;
}

int moduleInventoryItemFull(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer and item ID
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventoryItemFull: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventoryItemFull: Expected item ID as second argument");
    return 0;
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  itemid_t item = (itemid_t)lua_tointeger(L, 2);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  
  bool_t isFull = inventoryItemFull(inventory, item);
  lua_pushboolean(L, isFull);
  return 1;
}

int moduleInventorySort(lua_State *L) {
  assertNotNull(L, "Lua state cannot be NULL");

  // Requires inventory pointer, sort type and reverse flag
  if(!lua_islightuserdata(L, 1)) {
    luaL_error(L, "inventorySort: Expected inventory pointer as first argument");
    return 0;
  }

  if(!lua_isinteger(L, 2)) {
    luaL_error(L, "inventorySort: Expected sort type as second argument");
    return 0;
  }
  
  // Optional, reverse
  bool_t reverse = false;
  if(lua_gettop(L) >= 3) {
    if(!lua_isboolean(L, 3)) {
      luaL_error(L, "inventorySort: Expected reverse flag as third argument");
      return 0;
    }

    reverse = (bool_t)lua_toboolean(L, 3);
  }

  inventory_t *inventory = (inventory_t *)lua_touserdata(L, 1);
  inventorysort_t sortBy = (inventorysort_t)lua_tointeger(L, 2);

  assertNotNull(inventory, "Inventory pointer cannot be NULL.");
  inventorySort(inventory, sortBy, reverse);
  return 0;
}

void moduleItem(scriptcontext_t *context) {
  assertNotNull(context, "Script context cannot be NULL");

  // Item information
  
  // Bind BACKPACK const pointer
  scriptContextRegPointer(context, "BACKPACK", (void *)&BACKPACK);

  // Bind Methods
  scriptContextRegFunc(
    context, "inventoryItemExists", moduleInventoryItemExists
  );
  scriptContextRegFunc(context, "inventoryAdd", moduleInventoryAdd);
  scriptContextRegFunc(context, "inventorySet", moduleInventorySet);
  scriptContextRegFunc(context, "inventoryRemove", moduleInventoryRemove);
  scriptContextRegFunc(context, "inventoryGetCount", moduleInventoryGetCount);
  scriptContextRegFunc(context, "inventoryIsFull", moduleInventoryIsFull);
  scriptContextRegFunc(context, "inventoryItemFull", moduleInventoryItemFull);
  scriptContextRegFunc(context, "inventorySort", moduleInventorySort);
}