@* Global resource search — header-level palette.

   Keyboard:  ↑/↓ move the highlight, Enter navigates, Esc clears.
   Blur:      Clicking anywhere outside the input closes the dropdown.
*@

@using Microsoft.AspNetCore.Components.Web
@using RackPeek.Domain.Persistence
@using RackPeek.Domain.Resources
@using Shared.Rcl.Services

@inject IResourceCollection Repo
@inject NavigationManager Nav

<div class="relative">
    <input type="search"
           data-testid="global-search-input"
           placeholder="Search resources…"
           autocomplete="off"
           class="bg-zinc-800 text-zinc-200 placeholder-zinc-500
                  border border-zinc-700 rounded
                  px-3 py-1 text-sm w-72
                  focus:outline-none focus:border-emerald-400"
           @bind="_query"
           @bind:event="oninput"
           @bind:after="RunSearchAsync"
           @onkeydown="OnKeyDown"
           @onfocusout="OnFocusOut"/>

    @if (!string.IsNullOrWhiteSpace(_query))
    {
        <div data-testid="global-search-results"
             class="absolute left-0 right-0 mt-1 z-50
                    bg-zinc-900 border border-zinc-700 rounded
                    shadow-lg max-h-96 overflow-y-auto text-sm">

            @if (_results.Count == 0)
            {
                <div data-testid="global-search-no-results"
                     class="px-3 py-2 text-zinc-500 italic">
                    No matches.
                </div>
            }
            else
            {
                @for (var i = 0; i < _results.Count; i++)
                {
                    var r = _results[i];
                    var highlighted = i == _highlightedIndex;
                    var rowClass = highlighted
                        ? "bg-zinc-800 border-l-2 border-emerald-400"
                        : "hover:bg-zinc-800 border-l-2 border-transparent";

                    <button type="button"
                            data-testid="@($"global-search-result-{Sanitize(r.Kind)}-{Sanitize(r.Name)}")"
                            @onclick="() => OnResultSelected(r)"
                            class="@($"w-full text-left block px-3 py-2 text-zinc-200 border-b border-zinc-800 last:border-b-0 cursor-pointer {rowClass}")">

                        <div class="font-medium text-emerald-400">@r.Name</div>
                        <div data-testid="global-search-result-match"
                             class="text-xs text-zinc-500">
                            @r.Kind · via @r.MatchedField: @r.MatchedValue
                        </div>
                    </button>
                }
            }
        </div>
    }
</div>

@code {
    // Brief delay on focus-out so a click on a result button can fire first.
    // Browser event order is mousedown → blur → click, so the focus-out fires
    // before the click handler on the button. The delay lets the click register
    // before we close the dropdown.
    private const int _blurCloseDelayMs = 150;

    private string _query = string.Empty;
    private IReadOnlyList<SearchResult> _results = [];
    private int _highlightedIndex;

    private async Task RunSearchAsync()
    {
        // Reload every search so newly added / edited / deleted resources show up
        // without a hard page refresh. The repo layer is already in-memory, so
        // this is a cheap dictionary lookup, not a disk read.
        var resources = await Repo.GetAllOfTypeAsync<Resource>();
        _results = GlobalSearchService.Search(resources, _query);
        _highlightedIndex = 0;
    }

    private void OnKeyDown(KeyboardEventArgs e)
    {
        switch (e.Key)
        {
            case "ArrowDown":
                if (_results.Count > 0)
                    _highlightedIndex = Math.Min(_highlightedIndex + 1, _results.Count - 1);
                break;

            case "ArrowUp":
                if (_results.Count > 0)
                    _highlightedIndex = Math.Max(_highlightedIndex - 1, 0);
                break;

            case "Enter":
                if (_highlightedIndex >= 0 && _highlightedIndex < _results.Count)
                    OnResultSelected(_results[_highlightedIndex]);
                break;

            case "Escape":
                Close();
                break;
        }
    }

    private async Task OnFocusOut()
    {
        await Task.Delay(_blurCloseDelayMs);
        if (!string.IsNullOrEmpty(_query))
        {
            Close();
            StateHasChanged();
        }
    }

    private void OnResultSelected(SearchResult r)
    {
        Close();
        Nav.NavigateTo(r.Url);
    }

    private void Close()
    {
        _query = string.Empty;
        _results = [];
        _highlightedIndex = 0;
    }

    private static string Sanitize(string value) =>
        value.Replace(" ", "-").ToLowerInvariant();
}