using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Reflection.Emit;
using HarmonyLib;
using UnityEngine;
using UnityEngine.UI;

namespace CompressSave;

class PatchUILoadGame
{
    static UIButton decompressButton;

    [HarmonyTranspiler]
    [HarmonyPatch(typeof(UISaveGameWindow), "OnSelectedChange")]
    [HarmonyPatch(typeof(UILoadGameWindow), "OnSelectedChange")]
    static IEnumerable<CodeInstruction> OnSelectedChange_Transpiler(IEnumerable<CodeInstruction> instructions, ILGenerator generator)
    {
        var ReadHeader = typeof(GameSave).GetMethod("ReadHeaderAndDescAndProperty", BindingFlags.Static | BindingFlags.Public);
        if (ReadHeader == null) return instructions;
        var codes = new List<CodeInstruction>(instructions);
        for (int i = 0; i < codes.Count; i++)
        {
            var code = codes[i];
            if (code.opcode == OpCodes.Ldstr && code.OperandIs("#,##0"))
            {
                var iffalse = generator.DefineLabel();
                var callLabel = generator.DefineLabel();
                code.WithLabels(iffalse)
                    .operand = "(N)#,##0";
                codes[i + 1].WithLabels(callLabel);
                var IL = new List<CodeInstruction> {
                    new CodeInstruction(OpCodes.Ldloc_0),
                    new CodeInstruction(OpCodes.Ldfld, AccessTools.Field(typeof(CompressionGameSaveHeader),"IsCompressed")),
                    new CodeInstruction(OpCodes.Brfalse_S,iffalse),
                    new CodeInstruction(OpCodes.Ldstr,"(LZ4)#,##0"),
                    new CodeInstruction(OpCodes.Br_S,callLabel),
                };
                codes.InsertRange(i, IL);
                break;
            }
        }

        return codes.AsEnumerable();
    }

    [HarmonyPatch(typeof(UILoadGameWindow), "OnSelectedChange"), HarmonyPostfix]
    static void OnSelectedChange(UILoadGameWindow __instance, UIButton ___loadButton, Text ___prop3Text)
    {
        bool compressedSave = (___prop3Text != null &&___prop3Text.text.Contains("LZ4")) || (___loadButton.button.interactable == false && SaveUtil.IsCompressedSave(__instance.selected?.saveName));
        if (decompressButton)
            decompressButton.button.interactable = compressedSave;
    }

    [HarmonyPatch(typeof(UILoadGameWindow), "_OnOpen"), HarmonyPostfix]
    static void _OnOpen(UILoadGameWindow __instance, UIButton ___loadButton, GameObject ___loadSandboxGroup, List<UIGameSaveEntry> ___entries)
    {
        if (!decompressButton)
        {
            decompressButton = ___loadButton;

            decompressButton = (__instance.transform.Find("button-decompress")?.gameObject ?? GameObject.Instantiate(___loadButton.gameObject, ___loadButton.transform.parent)).GetComponent<UIButton>();

            ___loadSandboxGroup.transform.Translate(new Vector3(-2.5f, 0, 0));
            decompressButton.gameObject.name = "button-decompress";
            decompressButton.transform.Translate(new Vector3(-2.0f, 0, 0));
            decompressButton.button.image.color = new Color32(0, 0xf4, 0x92, 0x77);
            var localizer = decompressButton.transform.Find("button-text")?.GetComponent<Localizer>();
            var text = decompressButton.transform.Find("button-text")?.GetComponent<Text>();

            if (localizer)
            {
                localizer.stringKey = "Decompress".Translate();
                localizer.translation = "Decompress".Translate();
            }
            if (text)
                text.text = "Decompress".Translate();

            decompressButton.onClick += _ =>{ 
                if(SaveUtil.DecompressSave(__instance.selected.saveName, out var newfileName))
                {
                    __instance.RefreshList();
                    __instance.selected = ___entries.First(e => e.saveName == newfileName);
                }
            };
            decompressButton.button.interactable = false;
        }
    }
        
    public static void OnDestroy()
    {
        if (decompressButton)
            GameObject.Destroy(decompressButton.gameObject);
        decompressButton = null;
    }
}