using System;
using UnityEngine;

public class KitchenGameManager : MonoBehaviour {
    [SerializeField] private const float gamePlayingTimerMax = 300f;
    private bool isGamePaused;

    private State state;
    public static KitchenGameManager Instance { get; private set; }
    public float CountdownToStartTimer { get; private set; } = 1f;
    public float GamePlayingTimer { get; private set; }

    private void Awake() {
        Instance = this;
        state = State.WaitingToStart;
        GamePlayingTimer = gamePlayingTimerMax;
    }

    private void Start() {
        GameInput.Instance.OnPauseAction += GameInput_OnPauseAction;
        GameInput.Instance.OnInteractAction += GameInput_OnInteractAction;

        //DEBUG trigger game start automatically
        state = State.CountdownToStart;
        OnStateChanged?.Invoke(this, EventArgs.Empty);
    }

    private void Update() {
        switch (state) {
            case State.WaitingToStart:
                break;
            case State.CountdownToStart:
                CountdownToStartTimer -= Time.deltaTime;
                if (CountdownToStartTimer > 0f) return;

                state = State.GamePlaying;
                OnStateChanged?.Invoke(this, EventArgs.Empty);
                break;
            case State.GamePlaying:
                GamePlayingTimer -= Time.deltaTime;
                if (GamePlayingTimer > 0f) return;

                state = State.GameOver;
                GamePlayingTimer = gamePlayingTimerMax;
                OnStateChanged?.Invoke(this, EventArgs.Empty);
                break;
            case State.GameOver:
                break;
        }

        // Debug.Log(state);
    }

    public event EventHandler OnStateChanged;
    public event EventHandler OnGamePaused;
    public event EventHandler OnGameUnpaused;

    private void GameInput_OnPauseAction(object sender, EventArgs e) {
        TogglePauseGame();
    }

    private void GameInput_OnInteractAction(object sender, EventArgs e) {
        if (state == State.WaitingToStart) {
            state = State.CountdownToStart;
            OnStateChanged?.Invoke(this, EventArgs.Empty);
        }
    }

    public void TogglePauseGame() {
        isGamePaused = !isGamePaused;
        if (isGamePaused) {
            Time.timeScale = 0f;
            OnGamePaused?.Invoke(this, EventArgs.Empty);
        }
        else {
            Time.timeScale = 1f;
            OnGameUnpaused?.Invoke(this, EventArgs.Empty);
        }
    }

    public bool IsGamePlaying() {
        return state == State.GamePlaying;
    }

    public bool IsCountToStartActive() {
        return state == State.CountdownToStart;
    }

    public bool IsGameOver() {
        return state == State.GameOver;
    }

    public float GetGamePlayingTimerNormalized() {
        return 1 - GamePlayingTimer / gamePlayingTimerMax;
    }

    private enum State {
        WaitingToStart,
        CountdownToStart,
        GamePlaying,
        GameOver
    }
}