using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.UI;
using Vanguard.Api;
using Vanguard.Api.Contracts;
using Vanguard.Auth;
using Vanguard.Meta;

namespace Vanguard.UI
{
    /// <summary>История матчей в Lobby и вход в реплей.</summary>
    public sealed class HistoryView
    {
        private readonly MetaService _meta;
        private readonly AuthService _auth;
        private readonly Action _onBack;

        private readonly RectTransform _root;
        private readonly Text _status;
        private readonly RectTransform _content;
        private readonly ReplayView _replay;
        private bool _loading;

        public HistoryView(
            Transform parent,
            MetaService meta,
            AuthService auth,
            Action onBack)
        {
            _meta = meta;
            _auth = auth;
            _onBack = onBack;

            _root = UiKit.CreatePanel(parent, "HistoryScreen", new Color(0.018f, 0.03f, 0.06f, 0.96f));

            var top = UiKit.CreatePanel(_root, "TopBar", new Color(0.06f, 0.08f, 0.13f, 1f));
            top.anchorMin = new Vector2(0f, 1f);
            top.anchorMax = new Vector2(1f, 1f);
            top.pivot = new Vector2(0.5f, 1f);
            top.anchoredPosition = Vector2.zero;
            top.sizeDelta = new Vector2(0f, 88f);
            UiKit.AddHorizontalLayout(top, 22, 16);

            var back = UiKit.CreateButton(top, "Back", "← В лобби", () => _onBack(), 18);
            UiKit.SetPreferredHeight(back, 44f, 0f);

            var title = UiKit.CreateText(top, "Title", "История матчей", 32, Color.white, TextAnchor.MiddleLeft);
            title.fontStyle = FontStyle.Bold;
            UiKit.SetPreferredHeight(title, 46f);

            var hint = UiKit.CreateText(
                top, "Hint", "Только ваши матчи · реплей доступен участникам", 16,
                new Color(0.60f, 0.68f, 0.84f), TextAnchor.MiddleRight);
            UiKit.SetPreferredHeight(hint, 36f);

            var body = UiKit.CreatePanel(_root, "Body", new Color(0f, 0f, 0f, 0f));
            body.anchorMin = Vector2.zero;
            body.anchorMax = Vector2.one;
            body.offsetMin = new Vector2(44f, 30f);
            body.offsetMax = new Vector2(-44f, -110f);
            UiKit.AddVerticalLayout(body, 8, 10);

            var scroll = UiKit.CreateScrollView(body, "HistoryScroll", out _content, 8f);
            var scrollElement = scroll.gameObject.AddComponent<LayoutElement>();
            scrollElement.flexibleHeight = 1f;
            scrollElement.minHeight = 200f;

            _status = UiKit.CreateText(
                body, "Status", string.Empty, 18,
                new Color(0.62f, 0.68f, 0.82f), TextAnchor.MiddleLeft);
            UiKit.SetPreferredHeight(_status, 34f);

            _replay = new ReplayView(_root, _meta, HideReplay);
            _root.gameObject.SetActive(false);
        }

        public void Show()
        {
            UiKit.SetActive(_root, true);
            _replay.Hide();
            _ = LoadAsync();
        }

        public void Hide()
        {
            _replay.Hide();
            UiKit.SetActive(_root, false);
        }

        private async Task LoadAsync()
        {
            if (_loading)
                return;

            _loading = true;
            SetStatus("Загружаем историю…", new Color(0.62f, 0.68f, 0.82f));
            ClearChildren(_content);

            try
            {
                await _auth.EnsureAccessAsync();
                var history = await _meta.GetHistoryAsync();
                if (_root == null || !_root.gameObject.activeSelf)
                    return;

                Build(history.Items);
                SetStatus(
                    history.Items == null || history.Items.Count == 0
                        ? "Матчей пока нет."
                        : "Матчей: " + history.Items.Count + ".",
                    new Color(0.62f, 0.68f, 0.82f));
            }
            catch (ApiException exception)
            {
                SetStatus(exception.Message, new Color(1f, 0.55f, 0.45f));
            }
            catch (Exception exception)
            {
                Debug.LogException(exception);
                SetStatus("Не удалось загрузить историю.", new Color(1f, 0.55f, 0.45f));
            }
            finally
            {
                _loading = false;
            }
        }

        private void Build(IReadOnlyList<MatchHistoryDto> items)
        {
            ClearChildren(_content);
            if (items == null || items.Count == 0)
                return;

            foreach (var item in items)
                AddRow(item);
        }

        private void AddRow(MatchHistoryDto item)
        {
            var row = UiKit.CreatePanel(_content, "Match_" + item.MatchId, new Color(0.07f, 0.09f, 0.14f, 1f));
            var rowElement = row.gameObject.AddComponent<LayoutElement>();
            rowElement.preferredHeight = 96f;
            UiKit.AddHorizontalLayout(row, 14, 14);

            var info = UiKit.CreatePanel(row, "Info", new Color(0f, 0f, 0f, 0f));
            var infoElement = info.gameObject.AddComponent<LayoutElement>();
            infoElement.flexibleWidth = 1f;
            infoElement.preferredHeight = 64f;
            UiKit.AddVerticalLayout(info, 0, 2);

            var opponent = UiKit.CreateText(
                info,
                "Opponent",
                (item.Result == "win" ? "Победа" : item.Result == "loss" ? "Поражение" : "Ничья")
                + " против " + item.OpponentName,
                21,
                item.Result == "win" ? new Color(0.45f, 0.85f, 0.55f) : new Color(1f, 0.62f, 0.48f),
                TextAnchor.MiddleLeft);
            opponent.fontStyle = FontStyle.Bold;
            UiKit.SetPreferredHeight(opponent, 28f);

            var detail = UiKit.CreateText(
                info,
                "Detail",
                item.Mode + " · " + item.FinishReason + " · "
                + item.PlayedAt.ToLocalTime().ToString("dd.MM.yyyy HH:mm"),
                16,
                new Color(0.60f, 0.68f, 0.84f),
                TextAnchor.MiddleLeft);
            UiKit.SetPreferredHeight(detail, 24f);

            var rewards = UiKit.CreateText(
                row,
                "Rewards",
                "Gold " + item.Gold + " · XP " + item.Xp
                + "\nMMR " + item.MmrBefore + " → " + item.MmrAfter,
                16,
                new Color(0.72f, 0.78f, 0.92f));
            var rewardsElement = rewards.gameObject.AddComponent<LayoutElement>();
            rewardsElement.preferredWidth = 210f;
            rewardsElement.preferredHeight = 56f;

            var replay = UiKit.CreateButton(
                row,
                "Replay",
                item.ReplayAvailable ? "Реплей" : "Нет реплея",
                () => _replay.Show(item.MatchId),
                17);
            replay.interactable = item.ReplayAvailable;
            var replayElement = replay.gameObject.AddComponent<LayoutElement>();
            replayElement.preferredWidth = 130f;
            replayElement.preferredHeight = 46f;
            replayElement.flexibleWidth = 0f;
        }

        private void HideReplay()
        {
            _replay.Hide();
        }

        private void SetStatus(string text, Color color)
        {
            if (_status == null)
                return;

            _status.text = text ?? string.Empty;
            _status.color = color;
        }

        private static void ClearChildren(Transform parent)
        {
            for (var i = parent.childCount - 1; i >= 0; i--)
                UnityEngine.Object.Destroy(parent.GetChild(i).gameObject);
        }
    }
}