@page "/deck-builder"
@page "/deck-builder/{Id:guid}"
@rendermode InteractiveServer
@using Chrono.Model
@inject AppDbContext Db
@inject NavigationManager Nav

<PageTitle>@(Id == null ? "New Deck" : "Edit Deck") - Chrono CCG</PageTitle>

<div class="builder-topbar">
    <a href="/my-decks" class="btn btn-sm btn-outline-secondary">
        <i class="bi bi-arrow-left"></i> My Decks
    </a>
    <input @bind="deckName" @bind:event="oninput" class="form-control deck-name-input" placeholder="Deck name..." maxlength="80"/>
    <input @bind="deckSeason" @bind:event="oninput" class="form-control season-input" placeholder="Season (e.g. S1)" maxlength="20"/>
    <span class="validity-badge @(IsValid ? "badge-valid" : "badge-invalid")">
        <i class="bi @(IsValid ? "bi-check-circle-fill" : "bi-exclamation-circle-fill")"></i>
        @ValidationMessage
    </span>
    <button class="btn btn-primary save-btn" @onclick="SaveDeck" disabled="@isSaving">
        @if (isSaving)
        {
            <span class="spinner-border spinner-border-sm me-1"></span>
        }
        else
        {
            <i class="bi bi-floppy-fill me-1"></i>
        }
        Save
    </button>
    @if (!string.IsNullOrEmpty(saveMessage))
    {
        <span class="save-toast @(saveError ? "save-error" : "save-ok")">@saveMessage</span>
    }
</div>

<div class="builder-layout">

    <!-- LEFT: Card Browser -->
    <div class="browser-panel">
        <div class="category-tabs">
            <button class="tab @(categoryFilter == "" ? "active" : "")" @onclick='() => categoryFilter = ""'>
                <i class="bi bi-grid-3x3-gap-fill"></i> All
            </button>
            <button class="tab agent @(categoryFilter == "Agent" ? "active" : "")" @onclick='() => categoryFilter = "Agent"'>
                <i class="bi bi-person-fill"></i> Agents
            </button>
            <button class="tab agent @(categoryFilter == "Immortalized" ? "active" : "")" @onclick='() => categoryFilter = "Immortalized"'>
                <i class="bi bi-star-fill"></i> Immortalized
            </button>
            <button class="tab spell @(categoryFilter == "Spell" ? "active" : "")" @onclick='() => categoryFilter = "Spell"'>
                <i class="bi bi-wand"></i> Spells
            </button>
        </div>

        <div class="filter-bar">
            <div class="search-wrapper">
                <i class="bi bi-search search-icon"></i>
                <input @bind="search" @bind:event="oninput" class="form-control search-input" placeholder="Search cards..."/>
                @if (search.Length > 0)
                {
                    <button class="search-clear" @onclick='() => search = ""'><i class="bi bi-x-lg"></i></button>
                }
            </div>
            <select @bind="factionFilter" class="form-select filter-select">
                <option value="">All Factions</option>
                @foreach (var f in factions)
                {
                    <option value="@f">@f</option>
                }
            </select>
            <div class="col-picker" title="Cards per row">
                @for (var c = 1; c <= 6; c++)
                {
                    var cols = c;
                    <button class="col-btn @(gridColumns == cols ? "active" : "")" @onclick="() => gridColumns = cols">@cols</button>
                }
            </div>
        </div>

        <div class="browser-grid" style="--grid-cols: @gridColumns">
            @foreach (var card in BrowserCards)
            {
                var count = CountInDeck(card.Name);
                var maxed = count >= 3;
                <div @key="card.Name" class="browser-card @(count > 0 ? "in-deck" : "") @(maxed ? "maxed" : "")"
                     @onclick="() => AddCard(card)"
                     title="@(count > 0 ? $"{card.Name} ({count}/3)" : card.Name)">
                    <div class="browser-card-img">
                        <img src="@card.ImagePath" alt="@card.Name" loading="lazy"
                             onerror="this.style.display='none'"/>
                        @if (count > 0)
                        {
                            <span class="in-deck-count">@count</span>
                        }
                        @if (maxed)
                        {
                            <div class="maxed-overlay"><i class="bi bi-lock-fill"></i></div>
                        }
                    </div>
                    <div class="browser-card-name">@card.Name</div>
                </div>
            }
        </div>
    </div>

    <!-- RIGHT: Deck Panel -->
    <div class="deck-panel">

        <div class="deck-status-bar">
            <span class="card-count @(deckCards.Count == 40 ? "count-ok" : deckCards.Count > 40 ? "count-over" : "count-under")">
                <i class="bi bi-stack"></i> @deckCards.Count<span class="count-denom">/40</span>
            </span>
            <button class="btn btn-sm btn-outline-danger ms-auto" @onclick="ClearDeck" title="Clear deck">
                <i class="bi bi-trash3"></i> Clear
            </button>
        </div>

        @if (deckCards.Count > 0)
        {
            <div class="mana-curve">
                @for (var cost = 0; cost <= 10; cost++)
                {
                    var c = cost;
                    var costCount = ManaCurveData.TryGetValue(c, out var v) ? v : 0;
                    var maxVal = ManaCurveData.Values.DefaultIfEmpty(1).Max();
                    var heightPct = maxVal > 0 ? costCount * 100 / maxVal : 0;
                    <div class="curve-col">
                        <div class="curve-bar-wrap">
                            <span class="curve-count">@(costCount > 0 ? costCount.ToString() : "")</span>
                            <div class="curve-bar" style="height: @heightPct%"></div>
                        </div>
                        <div class="curve-label">@(c == 10 ? "10+" : c.ToString())</div>
                    </div>
                }
            </div>
        }

        <div class="deck-card-list">
            @if (DeckGroups.Count == 0)
            {
                <div class="deck-empty">
                    <i class="bi bi-collection"></i>
                    <span>Click cards on the left to add them</span>
                </div>
            }
            @foreach (var group in DeckGroups)
            {
                var cardData = group.Card;
                <div class="deck-row">
                    <img src="@cardData.ImagePath" alt="@cardData.Name" class="deck-row-img" loading="lazy"
                         onerror="this.style.display='none'"/>
                    <span class="deck-row-name">@cardData.Name</span>
                    @if (cardData.Cost.HasValue)
                    {
                        <span class="deck-row-cost"><i class="bi bi-lightning-fill"></i>@cardData.Cost</span>
                    }
                    <div class="deck-row-controls">
                        <button class="count-btn" @onclick="() => RemoveCard(cardData.Name)">−</button>
                        <span class="count-display">@group.Count</span>
                        <button class="count-btn" @onclick="() => AddCard(cardData)" disabled="@(group.Count >= 3)">+</button>
                    </div>
                </div>
            }
        </div>

        <div class="divers-section">
            <div class="section-header">
                <i class="bi bi-person-arms-up"></i> Divers
                <span class="section-count">@divers.Count(d => d != null)/2</span>
            </div>
            @for (var i = 0; i < 2; i++)
            {
                var idx = i;
                var diver = idx < divers.Count ? divers[idx] : null;
                <div class="diver-slot @(diver != null ? "filled" : "empty")" @onclick="() => OpenDiverPicker(idx)">
                    @if (diver != null)
                    {
                        var diverCard = AllCards.FirstOrDefault(c => c.Name == diver);
                        @if (diverCard != null)
                        {
                            <img src="@diverCard.ImagePath" class="diver-thumb" alt="@diver"
                                 onerror="this.style.display='none'"/>
                        }
                        <span class="diver-name">@diver</span>
                        <button class="diver-remove" @onclick:stopPropagation="true" @onclick="() => RemoveDiver(idx)">
                            <i class="bi bi-x"></i>
                        </button>
                    }
                    else
                    {
                        <i class="bi bi-plus-circle"></i>
                        <span>Select Diver @(idx + 1)</span>
                    }
                </div>
            }
        </div>

        <div class="notes-section">
            <div class="section-header"><i class="bi bi-pencil-fill"></i> Notes</div>
            <textarea @bind="deckNotes" class="form-control notes-input" rows="4"
                      placeholder="Strategy notes, matchup tips, card choices..."></textarea>
        </div>

    </div>
</div>

@if (showDiverPicker)
{
    <div class="modal-backdrop" @onclick="CloseDiverPicker"></div>
    <div class="diver-modal">
        <div class="diver-modal-header">
            <h5><i class="bi bi-person-arms-up"></i> Select Diver @(activeDiverSlot + 1)</h5>
            <button class="btn-close" @onclick="CloseDiverPicker"></button>
        </div>
        <div class="filter-bar mb-2">
            <div class="search-wrapper">
                <i class="bi bi-search search-icon"></i>
                <input @bind="diverSearch" @bind:event="oninput" class="form-control search-input" placeholder="Search..."/>
            </div>
        </div>
        <div class="diver-picker-grid">
            @foreach (var card in DiverPickerCards)
            {
                <div class="diver-picker-card" @onclick="() => SelectDiver(card.Name)">
                    <img src="@card.ImagePath" alt="@card.Name" loading="lazy" onerror="this.style.display='none'"/>
                    <span>@card.Name</span>
                </div>
            }
        </div>
    </div>
}

@code {
    [Parameter] public Guid? Id { get; set; }

    private List<CardData> AllCards => CardDatabase.Cards;
    private List<string> factions = [];

    private string deckName = "";
    private string deckSeason = "";
    private string deckNotes = "";
    private List<string> deckCards = [];
    private List<string> divers = [];

    private string search = "";
    private string categoryFilter = "";
    private string factionFilter = "";
    private int gridColumns = 4;

    private bool showDiverPicker;
    private int activeDiverSlot;
    private string diverSearch = "";

    private bool isSaving;
    private string saveMessage = "";
    private bool saveError;

    private bool IsValid => deckCards.Count == 40 && divers.Count == 2 && divers.All(d => d != null);

    private string ValidationMessage => (deckCards.Count, divers.Count) switch
    {
        (< 40, _) => $"{40 - deckCards.Count} cards short",
        (> 40, _) => $"{deckCards.Count - 40} cards over",
        (40, < 2) => "Need 2 divers",
        _ => "Valid"
    };

    private IEnumerable<CardData> BrowserCards => AllCards
        .Where(c => c.Category is "Agent" or "Spell" or "Immortalized")
        .Where(c => categoryFilter == "" || c.Category == categoryFilter)
        .Where(c => factionFilter == "" || c.Faction == factionFilter)
        .Where(c => search == "" || c.MatchesSearch(search));

    private record DeckGroup(CardData Card, int Count);

    private List<DeckGroup> DeckGroups => deckCards
        .GroupBy(name => name)
        .Select(g => new DeckGroup(AllCards.First(c => c.Name == g.Key), g.Count()))
        .OrderBy(g => g.Card.Cost ?? 99)
        .ThenBy(g => g.Card.Name)
        .ToList();

    private IEnumerable<CardData> DiverPickerCards
    {
        get
        {
            var inDeck = deckCards.ToHashSet();
            var otherDiverSlot = activeDiverSlot == 0
                ? (divers.Count > 1 ? divers[1] : null)
                : (divers.Count > 0 ? divers[0] : null);

            return AllCards
                .Where(c => c.Category is "Agent" or "Spell" or "Immortalized")
                .Where(c => !inDeck.Contains(c.Name))
                .Where(c => c.Name != otherDiverSlot)
                .Where(c => diverSearch == "" || c.MatchesSearch(diverSearch));
        }
    }

    private Dictionary<int, int> ManaCurveData
    {
        get
        {
            var result = new Dictionary<int, int>();
            foreach (var name in deckCards)
            {
                var card = AllCards.FirstOrDefault(c => c.Name == name);
                if (card == null) continue;
                var bucket = Math.Min(card.Cost ?? 0, 10);
                result[bucket] = result.GetValueOrDefault(bucket) + 1;
            }
            return result;
        }
    }

    private Dictionary<string, int> _deckCounts = new();

    private void RebuildDeckCounts() =>
        _deckCounts = deckCards.GroupBy(n => n).ToDictionary(g => g.Key, g => g.Count());

    private int CountInDeck(string name) =>
        _deckCounts.TryGetValue(name, out var c) ? c : 0;

    protected override async Task OnParametersSetAsync()
    {
        factions = AllCards
            .Where(c => c.Faction != null)
            .Select(c => c.Faction!)
            .Distinct()
            .OrderBy(f => f)
            .ToList();

        if (Id.HasValue)
            await LoadDeck(Id.Value);
    }

    private async Task LoadDeck(Guid id)
    {
        var deck = await Db.UserDecks.FindAsync(id);
        if (deck == null) return;

        deckName = deck.Name;
        deckSeason = deck.Season ?? "";
        deckNotes = deck.Notes ?? "";
        deckCards = new List<string>(deck.Cards);
        divers = new List<string>(deck.Divers);
        RebuildDeckCounts();
    }

    private void AddCard(CardData card)
    {
        if (CountInDeck(card.Name) >= 3) return;
        deckCards.Add(card.Name);
        RebuildDeckCounts();
    }

    private void RemoveCard(string name)
    {
        var idx = deckCards.LastIndexOf(name);
        if (idx >= 0) deckCards.RemoveAt(idx);
        RebuildDeckCounts();
    }

    private void ClearDeck()
    {
        deckCards.Clear();
        RebuildDeckCounts();
    }

    private void OpenDiverPicker(int slot)
    {
        activeDiverSlot = slot;
        diverSearch = "";
        showDiverPicker = true;
    }

    private void CloseDiverPicker() => showDiverPicker = false;

    private void SelectDiver(string name)
    {
        while (divers.Count <= activeDiverSlot)
            divers.Add(null!);
        divers[activeDiverSlot] = name;
        showDiverPicker = false;
    }

    private void RemoveDiver(int slot)
    {
        if (slot < divers.Count)
            divers.RemoveAt(slot);
    }

    private async Task SaveDeck()
    {
        if (string.IsNullOrWhiteSpace(deckName))
        {
            saveMessage = "Please enter a deck name.";
            saveError = true;
            return;
        }

        isSaving = true;
        saveMessage = "";

        try
        {
            if (Id.HasValue)
            {
                var existing = await Db.UserDecks.FindAsync(Id.Value);
                if (existing != null)
                {
                    existing.Name = deckName;
                    existing.Cards = new List<string>(deckCards);
                    existing.Divers = new List<string>(divers);
                    existing.Notes = deckNotes;
                    existing.Season = deckSeason;
                    existing.UpdatedAt = DateTime.UtcNow;
                    await Db.SaveChangesAsync();
                    saveMessage = "Saved!";
                    saveError = false;
                }
            }
            else
            {
                var deck = new UserDeck
                {
                    Name = deckName,
                    Cards = new List<string>(deckCards),
                    Divers = new List<string>(divers),
                    Notes = deckNotes,
                    Season = deckSeason,
                    UpdatedAt = DateTime.UtcNow
                };
                Db.UserDecks.Add(deck);
                await Db.SaveChangesAsync();
                saveMessage = "Saved!";
                saveError = false;
                Nav.NavigateTo($"/deck-builder/{deck.Id}", replace: true);
            }
        }
        catch (Exception ex)
        {
            saveMessage = $"Error: {ex.Message}";
            saveError = true;
        }
        finally
        {
            isSaving = false;
        }
    }
}