using Barotrauma.Extensions;
using Barotrauma.Items.Components;
using System.Collections.Generic;
using System.Linq;

namespace Barotrauma
{
    class AIObjectiveCleanupItems : AIObjectiveLoop<Item>
    {
        public override Identifier Identifier { get; set; } = "cleanup items".ToIdentifier();
        public override bool KeepDivingGearOn => true;
        public override bool AllowAutomaticItemUnequipping => false;
        protected override bool ForceOrderPriority => false;

        public readonly List<Item> prioritizedItems = new List<Item>();

        protected override int MaxTargets => 100;

        public AIObjectiveCleanupItems(Character character, AIObjectiveManager objectiveManager, Item prioritizedItem = null, float priorityModifier = 1)
            : base(character, objectiveManager, priorityModifier)
        {
            if (prioritizedItem != null)
            {
                prioritizedItems.Add(prioritizedItem);
            }
        }

        public AIObjectiveCleanupItems(Character character, AIObjectiveManager objectiveManager, IEnumerable<Item> prioritizedItems, float priorityModifier = 1)
            : base(character, objectiveManager, priorityModifier)
        {
            this.prioritizedItems.AddRange(prioritizedItems.Where(i => i != null));
        }

        protected override float GetTargetPriority()
        {
            if (Targets.None()) { return 0; }
            if (objectiveManager.IsOrder(this))
            {
                float prio = objectiveManager.GetOrderPriority(this);
                if (subObjectives.All(so => so.SubObjectives.None()))
                {
                    // If none of the subobjectives have subobjectives, no valid container was found. Don't allow running.
                    ForceWalk = true;
                }
                return prio;
            }
            return AIObjectiveManager.RunPriority - 0.5f;
        }

        protected override bool IsValidTarget(Item target)
        {
            System.Diagnostics.Debug.Assert(target.GetComponent<Pickable>() is { } pickable && !pickable.IsAttached, "Invalid target in AIObjectiveCleanUpItems - the the objective should only be checking pickable, non-attached items.");
            System.Diagnostics.Debug.Assert(target.Prefab.PreferredContainers.Any(), "Invalid target in AIObjectiveCleanUpItems - the the objective should only be checking items that have preferred containers defined.");

            // If the target was selected as a valid target, we'll have to accept it so that the objective can be completed.
            // The validity changes when a character picks the item up.
            if (!IsValidTarget(target, character, checkInventory: true)) { return Objectives.ContainsKey(target) && IsItemInsideValidSubmarine(target, character); }
            if (target.CurrentHull.FireSources.Count > 0) { return false; }
            foreach (Character c in Character.CharacterList)
            {
                if (c == character || !HumanAIController.IsActive(c)) { continue; }
                if (c.CurrentHull == target.CurrentHull && !HumanAIController.IsFriendly(c))
                {
                    // Don't clean up items in rooms that have enemies inside.
                    return false;
                }
            }
            return true;
        }

        protected override IEnumerable<Item> GetList() => Item.CleanableItems;

        protected override AIObjective ObjectiveConstructor(Item item)
            => new AIObjectiveCleanupItem(item, character, objectiveManager, priorityModifier: PriorityModifier)
            {
                IsPriority = prioritizedItems.Contains(item)
            };

        protected override void OnObjectiveCompleted(AIObjective objective, Item target)
            => HumanAIController.RemoveTargets<AIObjectiveCleanupItems, Item>(character, target);

        public static bool IsItemInsideValidSubmarine(Item item, Character character)
        {
            if (item.CurrentHull == null) { return false; }
            if (item.Submarine == null) { return false; }
            if (item.Submarine.TeamID != character.TeamID) { return false; }
            if (character.Submarine != null && !character.Submarine.IsConnectedTo(item.Submarine)) { return false; }
            return true;
        }

        public static bool IsValidContainer(Item container, Character character) =>
            container.HasTag(Tags.AllowCleanup) && 
            container.HasAccess(character) && 
            container.ParentInventory == null && container.OwnInventory != null && container.OwnInventory.AllItems.Any() && 
            container.GetComponent<ItemContainer>() != null &&
            IsItemInsideValidSubmarine(container, character) &&
            !container.IsClaimedByBallastFlora;

        public static bool IsValidTarget(Item item, Character character, bool checkInventory, bool allowUnloading = true, bool requireValidContainer = true, bool ignoreItemsMarkedForDeconstruction = true)
        {
            if (item == null) { return false; }
            if (item.DontCleanUp) { return false; }
            if (item.Illegitimate == character.IsOnPlayerTeam) { return false; }
            if (item.ParentInventory != null)
            {
                if (item.Container == null)
                {
                    // In a character inventory
                    return false;
                }
                if (!allowUnloading) { return false; }
                if (requireValidContainer && !IsValidContainer(item.Container, character)) { return false; }
            }
            if (ignoreItemsMarkedForDeconstruction && Item.DeconstructItems.Contains(item)) { return false; }
            if (!item.HasAccess(character)) { return false; }
            if (character != null && !IsItemInsideValidSubmarine(item, character)) { return false; }
            if (item.HasBallastFloraInHull) { return false; }
            //something (e.g. a pet) was eating the item within the last second - don't clean up
            if (item.LastEatenTime > Timing.TotalTimeUnpaused - 1.0) { return false; }
            var wire = item.GetComponent<Wire>();
            if (wire != null)
            {
                if (wire.Connections.Any(c => c != null)) { return false; }
            }
            else
            {
                var connectionPanel = item.GetComponent<ConnectionPanel>();
                if (connectionPanel != null && connectionPanel.Connections.Any(c => c.Wires.Count > 0))
                {
                    return false;
                }
            }
            if (item.GetComponent<Rope>() is { IsActive: true, Snapped: false })
            {
                // Don't clean up spears with an active rope component.
                return false;
            }
            if (!checkInventory)
            {
                return true;
            }
            return CanPutInInventory(character, item, allowWearing: false);
        }

        public override void OnDeselected()
        {
            base.OnDeselected();
            foreach (var subObjective in SubObjectives)
            {
                if (subObjective is AIObjectiveCleanupItem cleanUpObjective)
                {
                    cleanUpObjective.DropTarget();
                }
            }
        }
    }
}