@using System.ComponentModel.DataAnnotations
@using RackPeek.Domain.Persistence
@using RackPeek.Domain.Resources.Hardware
@using RackPeek.Domain.Resources.SystemResources
@inject IResourceCollection Repo

@if (IsOpen)
{
    <div class="fixed inset-0 z-50 flex items-center justify-center">
        <!-- Backdrop -->
        <div class="absolute inset-0 bg-black/70" @onclick="Cancel"></div>

        <!-- Modal -->
        <div class="relative bg-zinc-900 border border-zinc-800 rounded w-full max-w-lg p-4">
            <!-- Header -->
            <div class="flex justify-between items-center mb-4">
                <div class="text-zinc-100 text-sm font-medium">
                    @Title
                </div>

                <button class="text-zinc-400 hover:text-zinc-200" @onclick="Cancel">
                    ✕
                </button>
            </div>

            <EditForm Model="_model" OnValidSubmit="HandleAccept">
                <DataAnnotationsValidator/>

                <div class="space-y-3 text-sm">
                    <!-- Search -->
                    <div>
                        @* ReSharper disable once CSharpWarnings::CS8619 *@
                        <InputText class="w-full bg-zinc-800 border border-zinc-700 rounded px-2 py-1 text-zinc-100"
                                   placeholder="Search hardware or systems…"
                                   Value="@_search"
                                   ValueChanged="OnSearchChanged"
                                   ValueExpression="() => _search"
                                   @oninput="OnSearchInput"/>
                    </div>

                    <!-- Selection -->
                    <div>
                        <InputSelect class="w-full bg-zinc-800 border border-zinc-700 rounded px-2 py-1 text-zinc-100"
                                     @bind-Value="_model.Value">
                            <option value="">Select hardware or system…</option>

                            @foreach (var group in FilteredItems)
                            {
                                <optgroup label="@group.Key">
                                    @foreach (var item in group.Value)
                                    {
                                        <option value="@item.Value">@item.Label</option>
                                    }
                                </optgroup>
                            }
                        </InputSelect>

                        @* Optional helper text *@
                        @if (!string.IsNullOrWhiteSpace(_model.Value) && _lookup.TryGetValue(_model.Value!, out var selected))
                        {
                            <div class="mt-2 text-xs text-zinc-400">
                                Selected: <span class="text-zinc-200">@selected.Type</span>
                                <span class="text-zinc-600">•</span>
                                <span>@selected.Group</span>
                            </div>
                        }
                    </div>
                </div>

                <!-- Actions -->
                <div class="flex justify-end items-center mt-5 gap-2">
                    <button type="button"
                            class="px-3 py-1 rounded border border-zinc-700 text-zinc-300 hover:bg-zinc-800"
                            @onclick="Cancel">
                        Cancel
                    </button>

                    <button type="submit"
                            class="px-3 py-1 rounded bg-emerald-600 text-black hover:bg-emerald-500"
                            disabled="@(!CanAccept)">
                        Accept
                    </button>
                </div>
            </EditForm>
        </div>
    </div>
}

@code {
    /* ---------- Parameters ---------- */

    [Parameter] public bool IsOpen { get; set; }
    [Parameter] public EventCallback<bool> IsOpenChanged { get; set; }

    [Parameter] public string Title { get; set; } = "Select hardware or system";

    [Parameter] public string? Value { get; set; }

    [Parameter] public EventCallback<string?> OnAccept { get; set; }

    private SelectionFormModel _model = new();
    private string _search = string.Empty;

    private List<SelectionItem> _items = new();

    private Dictionary<string, SelectionItem> _lookup = new();

    private bool CanAccept => !string.IsNullOrWhiteSpace(_model.Value);

    /* ---------- Lifecycle ---------- */

    protected override async Task OnParametersSetAsync()
    {
        if (!IsOpen) return;

        // Load both sets
        var hardware = (await Repo.GetAllOfTypeAsync<Hardware>())
            .Select(h => SelectionItem.Hardware(h.Name, h.Kind))
            .ToList();

        var systems = (await Repo.GetAllOfTypeAsync<SystemResource>())
            .Select(s => SelectionItem.System(s.Name, string.IsNullOrWhiteSpace(s.Type) ? "System" : s.Type!))
            .ToList();

        _items = hardware
            .Concat(systems)
            .OrderBy(i => i.TypeSort)
            .ThenBy(i => i.Group)
            .ThenBy(i => i.Label)
            .ToList();

        _lookup = _items.ToDictionary(i => i.Value, i => i);

        _model = new SelectionFormModel { Value = Value };
        _search = string.Empty;
    }

    private IReadOnlyDictionary<string, List<SelectionItem>> FilteredItems =>
        _items
            .Where(i =>
                string.IsNullOrWhiteSpace(_search) ||
                i.Label.Contains(_search.Trim(), StringComparison.OrdinalIgnoreCase) ||
                i.Group.Contains(_search.Trim(), StringComparison.OrdinalIgnoreCase))
            .GroupBy(i => $"{i.Type} — {i.Group}")
            .ToDictionary(
                g => g.Key,
                g => g.OrderBy(i => i.Label).ToList());

    private async Task HandleAccept()
    {
        await OnAccept.InvokeAsync(_model.Value);
        await Close();
    }

    private async Task Cancel()
    {
        await Close();
    }

    private async Task Close()
    {
        _model = new SelectionFormModel();
        _search = string.Empty;
        await IsOpenChanged.InvokeAsync(false);
    }

    private void OnSearchChanged(string? value)
    {
        _search = value ?? string.Empty;
    }

    private void OnSearchInput(ChangeEventArgs e)
    {
        _search = e.Value?.ToString() ?? string.Empty;

        if (FilteredItems.SelectMany(g => g.Value).All(i => i.Value != _model.Value))
            _model.Value = null;
    }

    private sealed class SelectionFormModel
    {
        [Required] public string? Value { get; set; }
    }

    private sealed record SelectionItem(
        string Type,
        string Group,
        string Label,
        string Value,
        int TypeSort)
    {
        public static SelectionItem Hardware(string name, string kind)
        {
            return new SelectionItem("Hardware", kind, name, $"{name}", 0);
        }

        public static SelectionItem System(string name, string category)
        {
            return new SelectionItem("System", category, name, $"{name}", 1);
        }
    }

}