using UnityEngine;
using UnityEngine.UI;

public class QuestTrackerUI : MonoBehaviour
{
    public RectTransform content;
    public Text outputText;
    public Font uiFont;
    public Color titleColor = new Color(1f, 0.74f, 0.25f);
    public Color textColor = new Color(0.92f, 0.9f, 0.82f);

    private float refreshTimer;
    private string lastSignature;

    private void OnEnable()
    {
        Subscribe();
        Refresh();
    }

    private void Start()
    {
        Subscribe();
        Refresh();
    }

    private void OnDisable()
    {
        if (QuestManager.Instance != null)
        {
            QuestManager.Instance.OnQuestsChanged -= Refresh;
        }
    }

    private void Update()
    {
        refreshTimer -= Time.unscaledDeltaTime;
        if (refreshTimer > 0f)
        {
            return;
        }

        refreshTimer = 0.25f;
        Subscribe();

        string signature = BuildSignature();
        if (signature != lastSignature)
        {
            lastSignature = signature;
            Refresh();
        }
    }

    private void Subscribe()
    {
        if (QuestManager.Instance != null)
        {
            QuestManager.Instance.OnQuestsChanged -= Refresh;
            QuestManager.Instance.OnQuestsChanged += Refresh;
        }
    }

    public void Refresh()
    {
        if (outputText != null)
        {
            outputText.text = BuildDisplayText();
            return;
        }

        if (content == null)
        {
            return;
        }

        ClearContent();

        if (QuestManager.Instance == null || QuestManager.Instance.ActiveQuests.Count == 0)
        {
            CreateLine("Нет активных квестов", textColor, 15);
            return;
        }

        foreach (QuestState state in QuestManager.Instance.ActiveQuests)
        {
            if (state.questData == null)
            {
                continue;
            }

            CreateLine(state.questData.questName, titleColor, 16);
            for (int i = 0; i < state.questData.goals.Count; i++)
            {
                QuestGoal goal = state.questData.goals[i];
                CreateLine($"{goal.GetDisplayName()} {state.GetProgress(i)}/{goal.requiredAmount}", textColor, 14);
            }
        }
    }

    private string BuildDisplayText()
    {
        if (QuestManager.Instance == null || QuestManager.Instance.ActiveQuests.Count == 0)
        {
            return "Нет активных квестов";
        }

        System.Text.StringBuilder builder = new System.Text.StringBuilder();
        foreach (QuestState state in QuestManager.Instance.ActiveQuests)
        {
            if (state.questData == null)
            {
                continue;
            }

            builder.AppendLine(state.questData.questName);
            for (int i = 0; i < state.questData.goals.Count; i++)
            {
                QuestGoal goal = state.questData.goals[i];
                builder.Append("  ")
                    .Append(goal.GetDisplayName())
                    .Append(' ')
                    .Append(state.GetProgress(i))
                    .Append('/')
                    .Append(goal.requiredAmount)
                    .AppendLine();
            }
        }

        return builder.Length > 0 ? builder.ToString().TrimEnd() : "Нет активных квестов";
    }

    private string BuildSignature()
    {
        if (QuestManager.Instance == null)
        {
            return "quests:null";
        }

        System.Text.StringBuilder builder = new System.Text.StringBuilder();
        foreach (QuestState state in QuestManager.Instance.ActiveQuests)
        {
            if (state.questData == null)
            {
                continue;
            }

            builder.Append(state.questData.questId).Append(':').Append(state.status).Append(':');
            for (int i = 0; i < state.goalProgress.Count; i++)
            {
                builder.Append(state.goalProgress[i]).Append(',');
            }

            builder.Append('|');
        }

        return builder.ToString();
    }

    private void ClearContent()
    {
        for (int i = content.childCount - 1; i >= 0; i--)
        {
            Destroy(content.GetChild(i).gameObject);
        }
    }

    private void CreateLine(string value, Color color, int size)
    {
        GameObject line = new GameObject("Quest Tracker Line", typeof(RectTransform), typeof(Text));
        line.transform.SetParent(content, false);

        Text text = line.GetComponent<Text>();
        text.font = uiFont != null ? uiFont : Resources.GetBuiltinResource<Font>("Arial.ttf");
        text.fontSize = size;
        text.color = color;
        text.text = value;

        RectTransform rect = line.GetComponent<RectTransform>();
        rect.sizeDelta = new Vector2(0f, size + 8f);
    }
}