using System;
using System.Collections.Generic;
using UnityEngine;

namespace BumpCombat.Defense
{
    public static class DefenseTowerArt
    {
        private const string ResourceRoot = "DefenseTowers-v1/";
        private static readonly Dictionary<string, Sprite[]> Frames = new();

        public static ICollection<string> Keys => DefenseTowerArtDurations.Keys;

        public static int ExpectedFrameCount(string key)
        {
            return DefenseTowerArtDurations.FrameCount(key);
        }

        public static Sprite[] Load(string key)
        {
            if (string.IsNullOrEmpty(key))
            {
                return Array.Empty<Sprite>();
            }

            if (!Frames.TryGetValue(key, out Sprite[] sprites))
            {
                sprites = Resources.LoadAll<Sprite>(ResourceRoot + key);
                Array.Sort(sprites, CompareFrameNames);
                Frames.Add(key, sprites);
            }
            return sprites;
        }

        public static float FrameSeconds(string key, int frame)
        {
            return DefenseTowerArtDurations.Seconds(key, frame);
        }

        public static string BodyKey(DefenseTowerKind kind, int tier, string motion)
        {
            string family = kind switch
            {
                DefenseTowerKind.Direct => "Fire",
                DefenseTowerKind.Summon => "Summon",
                DefenseTowerKind.Lightning => "Lightning",
                DefenseTowerKind.Cold => "Ice",
                DefenseTowerKind.Seismic => "Control",
                _ => "Support",
            };
            return $"Bodies/{family}/T{tier}-{motion}";
        }

        private static int CompareFrameNames(Sprite left, Sprite right)
        {
            return FrameIndex(left.name).CompareTo(FrameIndex(right.name));
        }

        private static int FrameIndex(string name)
        {
            int separator = name.LastIndexOf('_');
            return separator >= 0 && int.TryParse(name.Substring(separator + 1), out int index)
                ? index : 0;
        }
    }
}