using Barotrauma.Items.Components;
using Microsoft.Xna.Framework;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.Linq;

namespace Barotrauma
{
    class CargoMission : Mission
    {
        private XElement itemConfig;

        private List<Item> items;

        private int requiredDeliveryAmount;

        public CargoMission(XElement element, Location[] locations)
            : base(element, locations)
        {
            itemConfig = element.Element("Items");

            requiredDeliveryAmount = ToolBox.GetAttributeInt(element, "requireddeliveryamount", 0);
        }

        private void InitItems()
        {
            items = new List<Item>();

            if (itemConfig==null)
            {
                DebugConsole.ThrowError("Failed to initialize items for cargo mission (itemConfig == null)");
                return;
            }

            foreach (XElement subElement in itemConfig.Elements())
            {
                LoadItemAsChild(subElement, null);
            }

            if (requiredDeliveryAmount == 0) requiredDeliveryAmount = items.Count;
        }

        private void LoadItemAsChild(XElement element, Item parent)
        {
            string itemName = ToolBox.GetAttributeString(element, "name", "");

            ItemPrefab itemPrefab = ItemPrefab.list.Find(ip => ip.Name == itemName) as ItemPrefab;
            if (itemPrefab==null)
            {
                DebugConsole.ThrowError("Couldn't spawn item for cargo mission: item prefab \""+element.Name.ToString()+"\" not found");
                return;
            }

            WayPoint cargoSpawnPos = WayPoint.GetRandom(SpawnType.Cargo, null, Submarine.MainSub, true);
            if (cargoSpawnPos==null)
            {
                DebugConsole.ThrowError("Couldn't spawn items for cargo mission, cargo spawnpoint not found");
                return;
            }

            var cargoRoom = cargoSpawnPos.CurrentHull;

            if (cargoRoom == null)
            {
                DebugConsole.ThrowError("A waypoint marked as Cargo must be placed inside a room!");
                return;
            }

            Vector2 position = new Vector2(
                cargoSpawnPos.Position.X + Rand.Range(-20.0f, 20.0f, false),
                cargoRoom.Rect.Y - cargoRoom.Rect.Height + itemPrefab.Size.Y / 2);

            var item = new Item(itemPrefab, position, cargoRoom.Submarine);
            item.FindHull();


            items.Add(item);
            
            if (parent != null) parent.Combine(item);
            
            foreach (XElement subElement in element.Elements())
            {
                int amount = ToolBox.GetAttributeInt(subElement, "amount", 1);
                for (int i = 0; i < amount; i++)
                {
                    LoadItemAsChild(subElement, item);
                }                    
            }
        }

        public override void Start(Level level)
        {
            InitItems();
        }

        public override void End()
        {
            if (Submarine.MainSub != null && Submarine.MainSub.AtEndPosition)
            {
                int deliveredItemCount = items.Count(i => i.CurrentHull != null && i.Condition > 0.0f);

                if (deliveredItemCount >= requiredDeliveryAmount)
                {
                    GiveReward();

                    completed = true;
                }
            }

            items.ForEach(i => i.Remove());
        }
    }
}