using System;
using System.Collections.Generic;
using GeometryTD.CustomUtility;
using GeometryTD.Definition;
using GeometryTD.UI;
using UnityEngine;

namespace GeometryTD.Entity
{
    public sealed class CombatSelectUseCaseConfigurator
    {
        private const int BuildOptionCount = 4;

        private readonly BuildTowerVisualInfo[] _buildTowerVisualInfos = new BuildTowerVisualInfo[BuildOptionCount];

        public void Configure(
            CombatSelectFormUseCase useCase,
            Func<int> coinProvider,
            Func<int, Func<bool>> buildActionFactory,
            Func<bool> upgradeAction,
            int upgradeCost,
            Func<bool> destroyAction,
            int destroyGain,
            int[] buildTowerCosts,
            int currentBuildTowerCount,
            BackpackInventoryData inventorySnapshot,
            IReadOnlyList<TowerItemData> participantTowers)
        {
            if (useCase == null)
            {
                return;
            }

            useCase.SetCoinProvider(coinProvider);

            Dictionary<long, MuzzleCompItemData> muzzleMap = BuildComponentMap(inventorySnapshot?.MuzzleComponents);
            Dictionary<long, BearingCompItemData> bearingMap = BuildComponentMap(inventorySnapshot?.BearingComponents);
            Dictionary<long, BaseCompItemData> baseMap = BuildComponentMap(inventorySnapshot?.BaseComponents);

            int availableBuildCount = Mathf.Clamp(currentBuildTowerCount, 0, BuildOptionCount);
            for (int i = 0; i < BuildOptionCount; i++)
            {
                bool isBuildAvailable = i < availableBuildCount;
                BuildTowerVisualInfo buildVisual = ResolveBuildTowerVisual(participantTowers, i, muzzleMap, bearingMap, baseMap);
                _buildTowerVisualInfos[i] = buildVisual;
                useCase.SetBuildAction(
                    i,
                    isBuildAvailable && buildActionFactory != null ? buildActionFactory.Invoke(i) : null,
                    GetBuildTowerCost(buildTowerCosts, i),
                    null,
                    isBuildAvailable,
                    buildVisual.BaseColor,
                    buildVisual.BearingColor,
                    buildVisual.MuzzleColor);
                useCase.SetBuildVisible(i, isBuildAvailable);
            }

            useCase.SetUpgradeAction(upgradeAction, Mathf.Max(0, upgradeCost));
            useCase.SetDestroyAction(destroyAction, Mathf.Max(0, destroyGain));
        }

        public BuildTowerVisualInfo GetBuildVisualInfo(int buildIndex)
        {
            if (buildIndex < 0 || buildIndex >= _buildTowerVisualInfos.Length)
            {
                return BuildTowerVisualInfo.Default;
            }

            return _buildTowerVisualInfos[buildIndex];
        }

        private static int GetBuildTowerCost(int[] buildTowerCosts, int buildIndex)
        {
            if (buildTowerCosts == null || buildIndex < 0 || buildIndex >= buildTowerCosts.Length)
            {
                return 0;
            }

            return Mathf.Max(0, buildTowerCosts[buildIndex]);
        }

        private static BuildTowerVisualInfo ResolveBuildTowerVisual(
            IReadOnlyList<TowerItemData> participantTowers,
            int buildIndex,
            IReadOnlyDictionary<long, MuzzleCompItemData> muzzleMap,
            IReadOnlyDictionary<long, BearingCompItemData> bearingMap,
            IReadOnlyDictionary<long, BaseCompItemData> baseMap)
        {
            if (participantTowers == null || buildIndex < 0 || buildIndex >= participantTowers.Count)
            {
                return BuildTowerVisualInfo.Default;
            }

            TowerItemData tower = participantTowers[buildIndex];
            if (tower == null)
            {
                return BuildTowerVisualInfo.Default;
            }

            Color muzzleColor = ResolveComponentColor(muzzleMap, tower.MuzzleComponentInstanceId);
            Color bearingColor = ResolveComponentColor(bearingMap, tower.BearingComponentInstanceId);
            Color baseColor = ResolveComponentColor(baseMap, tower.BaseComponentInstanceId);
            return new BuildTowerVisualInfo(muzzleColor, bearingColor, baseColor);
        }

        private static Color ResolveComponentColor<TComp>(IReadOnlyDictionary<long, TComp> componentMap, long componentId)
            where TComp : TowerCompItemData
        {
            if (componentMap == null || componentId <= 0)
            {
                return Color.white;
            }

            return componentMap.TryGetValue(componentId, out TComp component) && component != null
                ? IconColorGenerator.GenerateForComponent(component)
                : Color.white;
        }

        private static Dictionary<long, TComp> BuildComponentMap<TComp>(IReadOnlyList<TComp> items)
            where TComp : TowerCompItemData
        {
            Dictionary<long, TComp> map = new Dictionary<long, TComp>();
            if (items == null)
            {
                return map;
            }

            for (int i = 0; i < items.Count; i++)
            {
                TComp item = items[i];
                if (item == null || item.InstanceId <= 0)
                {
                    continue;
                }

                map[item.InstanceId] = item;
            }

            return map;
        }
    }

    public readonly struct BuildTowerVisualInfo
    {
        public static BuildTowerVisualInfo Default => new BuildTowerVisualInfo(Color.white, Color.white, Color.white);

        public BuildTowerVisualInfo(Color muzzleColor, Color bearingColor, Color baseColor)
        {
            MuzzleColor = muzzleColor;
            BearingColor = bearingColor;
            BaseColor = baseColor;
        }

        public Color MuzzleColor { get; }
        public Color BearingColor { get; }
        public Color BaseColor { get; }
    }
}