using UnityEngine;
using UnityEngine.UI;
using TMPro;

/// <summary>
/// Attach to any manager GameObject in the create-lobby scene.
/// On Start it nukes all Art placeholder children from the Canvas and builds
/// a complete mobile-portrait lobby-configuration screen entirely in code.
/// </summary>
public class HostLobbyUI : MonoBehaviour
{
    // ── Colours ───────────────────────────────────────────────────────────────
    static Color H(string hex) { ColorUtility.TryParseHtmlString(hex, out var c); return c; }
    static readonly Color C_BG      = H("#0D0F1A");
    static readonly Color C_HDR     = H("#141927");
    static readonly Color C_CARD    = H("#111525");
    static readonly Color C_BORDER  = H("#1E2540");
    static readonly Color C_ACCENT  = H("#3399FF");
    static readonly Color C_GREEN   = H("#2DB84B");
    static readonly Color C_MUTED   = new Color(0.47f, 0.53f, 0.67f);
    static readonly Color C_WHITE   = Color.white;
    static readonly Color C_INPUT   = H("#0A0D1A");

    // ── Live values ───────────────────────────────────────────────────────────
    private float _radius       = 500f;
    private int   _impostors    = 1;
    private int   _tasks        = 5;
    private string _playerName  = "";

    // ── UI refs ───────────────────────────────────────────────────────────────
    private TMP_Text _radiusValueLabel;
    private TMP_Text _impostorValueLabel;
    private TMP_Text _taskValueLabel;
    private TMP_Text _statusText;

    void Start()
    {
        // Pre-populate from GameManager defaults
        var gm = GameManager.Instance;
        if (gm != null)
        {
            _radius    = (float)gm.pendingRadius;
            _impostors = gm.pendingImpostorCount;
            _tasks     = gm.pendingTaskCount;
            _playerName = gm.displayName ?? "";
        }

        var canvasGO = GameObject.Find("Canvas");
        if (canvasGO == null)
        {
            Debug.LogError("[HostLobbyUI] No Canvas found!");
            return;
        }

        // Nuke all Art placeholder children
        var kill = new System.Collections.Generic.List<GameObject>();
        foreach (Transform child in canvasGO.transform)
            kill.Add(child.gameObject);
        foreach (var go in kill)
            DestroyImmediate(go);

        // Disable scene-changer components that bypass our logic
        foreach (var sc in canvasGO.GetComponentsInChildren<CudlikZmenaSceny>(true))
            sc.enabled = false;

        Build(canvasGO.GetComponent<RectTransform>() ?? canvasGO.AddComponent<RectTransform>());
    }

    // ── Builder ───────────────────────────────────────────────────────────────
    void Build(RectTransform root)
    {
        // Full-screen background
        var bg = MakeRT("BG", root);
        Stretch(bg);
        bg.gameObject.AddComponent<CanvasRenderer>();
        Img(bg, C_BG);

        // ── Header bar ───────────────────────────────────────────────────────
        var hdr = MakeRT("Header", root);
        Anchor(hdr, new Vector2(0,1), new Vector2(1,1), new Vector2(0,-80), new Vector2(0,0));
        Img(hdr, C_HDR);
        var hdrTxt = Txt("Create Lobby", hdr, 28, C_WHITE, TextAlignmentOptions.Center, bold: true);
        Stretch(hdrTxt.rectTransform);

        // ── Scroll body ───────────────────────────────────────────────────────
        var scroll = MakeRT("Scroll", root);
        Anchor(scroll, new Vector2(0,0), new Vector2(1,1), new Vector2(0,80), new Vector2(0,-80));
        var sf = scroll.gameObject.AddComponent<ScrollRect>();
        sf.horizontal = false;
        Img(scroll, new Color(0,0,0,0));

        var content = MakeRT("Content", scroll);
        content.anchorMin = new Vector2(0,1);
        content.anchorMax = new Vector2(1,1);
        content.pivot     = new Vector2(0.5f, 1);
        content.offsetMin = Vector2.zero;
        content.offsetMax = Vector2.zero;
        var vlg = content.gameObject.AddComponent<VerticalLayoutGroup>();
        vlg.padding = new RectOffset(16, 16, 12, 12);
        vlg.spacing = 12;
        vlg.childForceExpandWidth  = true;
        vlg.childForceExpandHeight = false;
        var csf = content.gameObject.AddComponent<ContentSizeFitter>();
        csf.verticalFit = ContentSizeFitter.FitMode.PreferredSize;

        sf.content  = content;
        sf.viewport = scroll;

        // ── Player name card ─────────────────────────────────────────────────
        AddSectionLabel("PLAYER NAME", content);
        var nameCard = AddCard(content, 70);
        var nameInput = MakeInputField("Your name", nameCard, _playerName);
        Stretch(nameInput.GetComponent<RectTransform>());
        nameInput.onEndEdit.AddListener(v =>
        {
            _playerName = v.Trim();
            var gm2 = GameManager.Instance;
            if (gm2 != null) gm2.displayName = _playerName;
            PlayerPrefs.SetString("PlayerName", _playerName);
        });

        // ── Radius card ───────────────────────────────────────────────────────
        AddSectionLabel("PLAY AREA RADIUS", content);
        var radCard = AddCard(content, 110);
        var radRT = radCard.GetComponent<RectTransform>();

        var radLbl = MakeRT("RadLbl", radRT);
        Anchor(radLbl, new Vector2(0,1), new Vector2(1,1), new Vector2(12,-40), new Vector2(-12,-4));
        var rt = radLbl.gameObject;
        var radTmp = rt.AddComponent<TextMeshProUGUI>();
        radTmp.text = RadiusLabel(_radius);
        radTmp.fontSize = 20; radTmp.color = C_ACCENT;
        radTmp.alignment = TextAlignmentOptions.Center;
        _radiusValueLabel = radTmp;

        var slider = MakeRT("RadSlider", radRT).gameObject.AddComponent<Slider>();
        var srt = slider.GetComponent<RectTransform>();
        Anchor(srt, new Vector2(0,0), new Vector2(1,0), new Vector2(16, 14), new Vector2(-16, 44));
        slider.minValue = 100; slider.maxValue = 2000; slider.value = _radius;
        BuildSliderVisuals(slider, C_ACCENT);
        slider.onValueChanged.AddListener(v =>
        {
            _radius = v;
            _radiusValueLabel.text = RadiusLabel(v);
            var gm2 = GameManager.Instance;
            if (gm2 != null) gm2.pendingRadius = v;
        });

        // ── Impostor count card ───────────────────────────────────────────────
        AddSectionLabel("IMPOSTORS", content);
        var impCard = AddCard(content, 80);
        BuildStepper(impCard.GetComponent<RectTransform>(), ref _impostors, 1, 4,
            v => { var gm2 = GameManager.Instance; if (gm2 != null) gm2.pendingImpostorCount = v; },
            out _impostorValueLabel);

        // ── Task count card ───────────────────────────────────────────────────
        AddSectionLabel("TASKS PER PLAYER", content);
        var taskCard = AddCard(content, 80);
        BuildStepper(taskCard.GetComponent<RectTransform>(), ref _tasks, 1, 15,
            v => { var gm2 = GameManager.Instance; if (gm2 != null) gm2.pendingTaskCount = v; },
            out _taskValueLabel);

        // ── Status text ───────────────────────────────────────────────────────
        var statusCard = AddCard(content, 40);
        _statusText = Txt("", statusCard.GetComponent<RectTransform>(), 16, C_MUTED, TextAlignmentOptions.Center);
        Stretch(_statusText.rectTransform);

        // ── Footer create button ──────────────────────────────────────────────
        var footer = MakeRT("Footer", root);
        Anchor(footer, new Vector2(0,0), new Vector2(1,0), new Vector2(0,0), new Vector2(0,80));
        Img(footer, C_HDR);
        var btnRT = MakeRT("CreateBtn", footer);
        Anchor(btnRT, new Vector2(0.1f,0.15f), new Vector2(0.9f,0.85f), Vector2.zero, Vector2.zero);
        var btn = btnRT.gameObject.AddComponent<Button>();
        var btnImg = btnRT.gameObject.AddComponent<Image>();
        btnImg.color = C_GREEN;
        btn.targetGraphic = btnImg;
        var cb = btn.colors; cb.pressedColor = C_GREEN * 0.7f; btn.colors = cb;
        var btnTxt = Txt("CREATE LOBBY", btnRT, 22, C_WHITE, TextAlignmentOptions.Center, bold: true);
        Stretch(btnTxt.rectTransform);
        btn.onClick.AddListener(OnCreateClicked);

        // ── Back button ───────────────────────────────────────────────────────
        var backRT = MakeRT("BackBtn", root);
        Anchor(backRT, new Vector2(0,1), new Vector2(0,1), new Vector2(8,-72), new Vector2(72,-8));
        var backBtn = backRT.gameObject.AddComponent<Button>();
        var backImg = backRT.gameObject.AddComponent<Image>();
        backImg.color = new Color(1,1,1,0);
        backBtn.targetGraphic = backImg;
        var backTxt = Txt("←", backRT, 28, C_MUTED, TextAlignmentOptions.Center);
        Stretch(backTxt.rectTransform);
        backBtn.onClick.AddListener(() => UnityEngine.SceneManagement.SceneManager.LoadScene("main menu asi idk lol"));
    }

    // ── Actions ───────────────────────────────────────────────────────────────
    void OnCreateClicked()
    {
        var gm = GameManager.Instance;
        if (gm == null) { SetStatus("GameManager not found!", Color.red); return; }

        if (string.IsNullOrWhiteSpace(_playerName))
        {
            SetStatus("Enter a player name first.", Color.yellow);
            return;
        }

        gm.pendingRadius        = _radius;
        gm.pendingImpostorCount = _impostors;
        gm.pendingTaskCount     = _tasks;
        gm.displayName          = _playerName;

        SetStatus("Connecting…", C_MUTED);
        gm.CreateLobbyButton();
    }

    void SetStatus(string msg, Color col)
    {
        if (_statusText == null) return;
        _statusText.text  = msg;
        _statusText.color = col;
    }

    // ── UI helpers ────────────────────────────────────────────────────────────
    static string RadiusLabel(float v) => $"{Mathf.RoundToInt(v)} m";

    void BuildStepper(RectTransform parent, ref int val, int min, int max,
        System.Action<int> onChange, out TMP_Text label)
    {
        int captured = val; // local copy for closures

        // minus
        var minusRT = MakeRT("Minus", parent);
        Anchor(minusRT, new Vector2(0,0), new Vector2(0,1), new Vector2(8,8), new Vector2(72,-8));
        var minusBtn = minusRT.gameObject.AddComponent<Button>();
        var minusImg = minusRT.gameObject.AddComponent<Image>(); minusImg.color = C_BORDER;
        minusBtn.targetGraphic = minusImg;
        var minusTxt = Txt("−", minusRT, 28, C_WHITE, TextAlignmentOptions.Center);
        Stretch(minusTxt.rectTransform);

        // label
        var lblRT = MakeRT("Val", parent);
        Stretch(lblRT);
        var lbl = Txt(captured.ToString(), lblRT, 26, C_WHITE, TextAlignmentOptions.Center, bold: true);
        label = lbl;

        // plus
        var plusRT = MakeRT("Plus", parent);
        Anchor(plusRT, new Vector2(1,0), new Vector2(1,1), new Vector2(-72,8), new Vector2(-8,-8));
        var plusBtn = plusRT.gameObject.AddComponent<Button>();
        var plusImg = plusRT.gameObject.AddComponent<Image>(); plusImg.color = C_ACCENT;
        plusBtn.targetGraphic = plusImg;
        var plusTxt = Txt("+", plusRT, 28, C_WHITE, TextAlignmentOptions.Center);
        Stretch(plusTxt.rectTransform);

        minusBtn.onClick.AddListener(() =>
        {
            captured = Mathf.Max(min, captured - 1);
            lbl.text = captured.ToString();
            onChange?.Invoke(captured);
        });
        plusBtn.onClick.AddListener(() =>
        {
            captured = Mathf.Min(max, captured + 1);
            lbl.text = captured.ToString();
            onChange?.Invoke(captured);
        });

        // write back initial
        val = captured;
    }

    static void BuildSliderVisuals(Slider s, Color fillColor)
    {
        // Background track
        var bgRT = MakeRT("Background", s.GetComponent<RectTransform>());
        Stretch(bgRT);
        bgRT.gameObject.AddComponent<CanvasRenderer>();
        var bgImg = bgRT.gameObject.AddComponent<Image>(); bgImg.color = new Color(0.15f,0.18f,0.28f);

        // Fill area
        var fillArea = MakeRT("Fill Area", s.GetComponent<RectTransform>());
        Anchor(fillArea, new Vector2(0,0.25f), new Vector2(1,0.75f), new Vector2(5,0), new Vector2(-5,0));
        var fillRT = MakeRT("Fill", fillArea);
        fillRT.anchorMin = Vector2.zero; fillRT.anchorMax = Vector2.one;
        fillRT.offsetMin = Vector2.zero; fillRT.offsetMax = Vector2.zero;
        fillRT.gameObject.AddComponent<CanvasRenderer>();
        var fillImg = fillRT.gameObject.AddComponent<Image>(); fillImg.color = fillColor;
        s.fillRect = fillRT;

        // Handle area
        var handleArea = MakeRT("Handle Slide Area", s.GetComponent<RectTransform>());
        Stretch(handleArea);
        var handleRT = MakeRT("Handle", handleArea);
        handleRT.sizeDelta = new Vector2(28, 28);
        handleRT.anchorMin = new Vector2(0, 0.5f); handleRT.anchorMax = new Vector2(0, 0.5f);
        handleRT.anchoredPosition = Vector2.zero;
        handleRT.gameObject.AddComponent<CanvasRenderer>();
        var hImg = handleRT.gameObject.AddComponent<Image>(); hImg.color = Color.white;
        s.handleRect = handleRT;
        s.targetGraphic = hImg;
    }

    static void AddSectionLabel(string text, RectTransform parent)
    {
        var rt = MakeRT("Lbl_" + text, parent);
        var le = rt.gameObject.AddComponent<LayoutElement>(); le.preferredHeight = 28;
        var tmp = rt.gameObject.AddComponent<TextMeshProUGUI>();
        tmp.text = text; tmp.fontSize = 13; tmp.color = new Color(0.47f,0.53f,0.67f);
        tmp.fontStyle = FontStyles.Bold; tmp.alignment = TextAlignmentOptions.Left;
    }

    static RectTransform AddCard(RectTransform parent, float height)
    {
        var rt = MakeRT("Card", parent);
        var le = rt.gameObject.AddComponent<LayoutElement>(); le.preferredHeight = height;
        var img = rt.gameObject.AddComponent<Image>(); img.color = H("#111525");
        // border via outline
        var outline = rt.gameObject.AddComponent<Outline>();
        outline.effectColor = H("#1E2540");
        outline.effectDistance = new Vector2(1, -1);
        return rt;
    }

    static TMP_InputField MakeInputField(string placeholder, RectTransform parent, string initialValue)
    {
        var go = new GameObject("InputField");
        var rt = go.AddComponent<RectTransform>();
        rt.SetParent(parent, false);
        rt.localScale = Vector3.one;

        var img = go.AddComponent<Image>(); img.color = H("#0A0D1A");
        var field = go.AddComponent<TMP_InputField>();

        var textArea = MakeRT("Text Area", rt);
        Stretch(textArea);
        textArea.offsetMin = new Vector2(10, 4);
        textArea.offsetMax = new Vector2(-10, -4);
        var areaImg = textArea.gameObject.AddComponent<Image>(); areaImg.color = new Color(0,0,0,0);
        var mask = textArea.gameObject.AddComponent<RectMask2D>();

        var phRT = MakeRT("Placeholder", textArea);
        Stretch(phRT);
        var phTmp = phRT.gameObject.AddComponent<TextMeshProUGUI>();
        phTmp.text = placeholder; phTmp.fontSize = 20;
        phTmp.color = new Color(0.47f, 0.53f, 0.67f);
        phTmp.alignment = TextAlignmentOptions.MidlineLeft;

        var txtRT = MakeRT("Text", textArea);
        Stretch(txtRT);
        var txtTmp = txtRT.gameObject.AddComponent<TextMeshProUGUI>();
        txtTmp.fontSize = 20; txtTmp.color = Color.white;
        txtTmp.alignment = TextAlignmentOptions.MidlineLeft;

        field.textViewport      = textArea;
        field.textComponent     = txtTmp;
        field.placeholder       = phTmp;
        field.text              = initialValue;
        field.targetGraphic     = img;

        return field;
    }

    static RectTransform MakeRT(string name, RectTransform parent)
    {
        var go = new GameObject(name);
        var rt = go.AddComponent<RectTransform>();
        rt.SetParent(parent, false);
        rt.localScale = Vector3.one;
        return rt;
    }

    static void Stretch(RectTransform rt)
    {
        rt.anchorMin = Vector2.zero; rt.anchorMax = Vector2.one;
        rt.offsetMin = Vector2.zero; rt.offsetMax = Vector2.zero;
    }

    static void Anchor(RectTransform rt, Vector2 aMin, Vector2 aMax, Vector2 offMin, Vector2 offMax)
    {
        rt.anchorMin = aMin; rt.anchorMax = aMax;
        rt.offsetMin = offMin; rt.offsetMax = offMax;
    }

    static Image Img(RectTransform rt, Color c)
    {
        rt.gameObject.AddComponent<CanvasRenderer>();
        var img = rt.gameObject.AddComponent<Image>(); img.color = c; return img;
    }

    static TextMeshProUGUI Txt(string text, RectTransform parent, float size, Color color,
        TextAlignmentOptions align, bool bold = false)
    {
        var rt = MakeRT("T_" + text, parent);
        var tmp = rt.gameObject.AddComponent<TextMeshProUGUI>();
        tmp.text = text; tmp.fontSize = size; tmp.color = color; tmp.alignment = align;
        if (bold) tmp.fontStyle = FontStyles.Bold;
        return tmp;
    }
}