using MonoMod;
using MU3.Battle;
using MU3.Game;
using MU3.Notes;
using MU3.Util;
using System;
using UnityEngine;

namespace MU3.Sequence;

class patch_PlayMusic: PlayMusic {
    private static readonly TimeSpan HOLD_DURATION = TimeSpan.FromSeconds(0.67f);
    private static readonly TimeSpan ROLL_DURATION = TimeSpan.FromSeconds(0.5f);

    private double fadeOut(double progress, double min, double max)
        => min + (max - min) * (1.0 - Math.Pow(1.0 - progress, 2.0));
    private double fadeIn(double progress, double min, double max)
        => min + (max - min) * Math.Pow(progress, 2.0);
    private bool isHolding
        => Singleton<UIInput>.instance.getStateOn(UIInput.Key.MenuLeft)
        || Singleton<UIInput>.instance.getStateOn(UIInput.Key.MenuRight);
    private patch_NotesManager ntMgr => (patch_NotesManager)_gameEngine?.notesManager;

    private GameEngine _gameEngine;
    private SessionInfo _sessionInfo;
    private bool _isForceEndBattle;

    private bool _isRolling;
    private bool _isHoldingAck;
    private float _totalRollingFrame;
    private DateTime _rollingStartTime;
    private DateTime _holdingStartTime;
    private float _enemyPosX;

    [MonoModIgnore]
    private extern bool isPartyPlay();

    private extern void orig_Execute_Play();
    private void Execute_Play() {
        if(isPartyPlay() || _sessionInfo.isTutorial) {
            orig_Execute_Play();
            return;
        }

        if(_isRolling) {
            TimeSpan timeSpan = CustomDateTime.Now - _rollingStartTime;
            if(timeSpan <= ROLL_DURATION) {
                double num1 = fadeOut(timeSpan.TotalMilliseconds / ROLL_DURATION.TotalMilliseconds, 0.0, 1.0);
                double num2 = fadeIn(timeSpan.TotalMilliseconds / ROLL_DURATION.TotalMilliseconds, 0.0, 1.0);
                ntMgr.setFrameForce(_totalRollingFrame * (float)(1.0 - num1));
                ntMgr.enemyOffset = new Vector3(
                    ntMgr.enemyOffset.x + (_enemyPosX - ntMgr.getEnemyPos().x), 20f * (float)num2, 0.0f
                );
            } else {
                endRolling();
            }
        } else if(isHolding) {
            if(!_isHoldingAck) {
                _holdingStartTime = CustomDateTime.Now;
                _isHoldingAck = true;
            }

            TimeSpan ts = CustomDateTime.Now - _holdingStartTime;
            if(ts > HOLD_DURATION) {
                if(Singleton<UIInput>.instance.getStateOn(UIInput.Key.MenuRight)) {
                    startRolling();
                } else {
                    skipPlay();
                }
            }
            orig_Execute_Play();
        } else {
            _isHoldingAck = false;
            orig_Execute_Play();
        }
    }

    private extern void orig_Execute_DispCombo();
    private void Execute_DispCombo() {
        orig_Execute_DispCombo();

        if(Singleton<UIInput>.instance.getStateOn(UIInput.Key.MenuRight) && ntMgr.retireResult != RetireResult.None && !isPartyPlay()) {
            startRolling();
            endRolling();
            _gameEngine.battleUI.skipDispRetireResult();
            setNextState(EState.Play);
        }
    }

    private extern void orig_Execute_DispFinish();
    private void Execute_DispFinish() {
        orig_Execute_DispFinish();

        if(Singleton<UIInput>.instance.getStateOn(UIInput.Key.MenuRight) && ntMgr.retireResult != RetireResult.None && !isPartyPlay()) {
            ntMgr.stopPlay();
            ntMgr.setPause(false);
            _gameEngine.reset();
            Singleton<GameSound>.instance.gameBGM.stop();
            setNextState(EState.Init);
        }
    }

    private void startRolling() {
        _isRolling = true;
        _totalRollingFrame = ntMgr.getCurrentFrame();
        _rollingStartTime = CustomDateTime.Now;
        _enemyPosX = ntMgr.getEnemyPos().x;
        _gameEngine.destroyAllies();
        ntMgr.forceRecover(recover: 100);
        Singleton<GameSound>.instance.gameBGM.stop();
    }

    private void endRolling() {
        _isRolling = false;
        _isForceEndBattle = false;

        ntMgr.stopPlay();
        ntMgr.setPause(false);
        ntMgr.reset();

        // This has to go first or otherwise enemies will shrink
        _gameEngine.createPlayers();

        _gameEngine.counters.reset();
        _gameEngine.enemyManager.destroy();

        ntMgr.reloadScore(_gameEngine.IsStageDazzling);
        _gameEngine.battleReward.initialize(_sessionInfo);
        _gameEngine.enemyManager.initialize();
        _gameEngine.reset();

        ntMgr.startPlay(0.0f);
        ntMgr.led.setGameColor(true);
        Singleton<GameSound>.instance.gameBGM.playMusic(_sessionInfo.musicData, 0);
    }

    private void skipPlay() {
        Singleton<Mod.State>.instance.SkipPlay = true;
        setNextState(EState.End);
        destroy();
        ntMgr.stopPlay();
        _gameEngine.destroyAllies();
        _gameEngine.finishGame();
        _gameEngine.playFinish();
    }
}