@inject ILibraryDiscoveryService LibraryDiscovery

@* Library name field with a picker: type a title, or click Browse to load and
   choose from the libraries on the selected site. *@
<div class="form-group library-picker">
    <label class="form-label">@Label</label>
    <div class="flex-row" style="gap:8px;align-items:stretch">
        <input class="form-input" style="flex:1"
               placeholder="@Placeholder"
               value="@Library"
               @oninput="OnTextInput"
               disabled="@Disabled" />
        <button type="button" class="btn btn-secondary"
                @onclick="Browse"
                disabled="@(Disabled || _loading)">
            @(_loading ? "Loading…" : "Browse")
        </button>
    </div>

    @if (!string.IsNullOrEmpty(_error))
    {
        <div class="alert alert-error mt-8">@_error</div>
    }

    @if (_open)
    {
        <div class="library-picker-list" style="max-height:200px;overflow:auto;border:1px solid var(--border);border-radius:4px;padding:4px;margin-top:6px">
            @foreach (var lib in _libraries)
            {
                <button type="button"
                        class="library-picker-item @(string.Equals(lib, Library, StringComparison.OrdinalIgnoreCase) ? "active" : "")"
                        style="display:block;width:100%;text-align:left;padding:4px 8px;border:none;background:none;cursor:pointer;border-radius:3px"
                        @onclick="() => Pick(lib)">
                    @lib
                </button>
            }
            @if (_libraries.Count == 0)
            {
                <div class="text-muted" style="padding:6px">No document libraries found on this site.</div>
            }
        </div>
    }
</div>

@code {
    [Parameter, EditorRequired] public TenantProfile Profile { get; set; } = default!;
    [Parameter] public string? SiteUrl { get; set; }
    [Parameter] public string Library { get; set; } = string.Empty;
    [Parameter] public EventCallback<string> LibraryChanged { get; set; }
    [Parameter] public string Label { get; set; } = "Library";
    [Parameter] public string Placeholder { get; set; } = "Shared Documents";
    [Parameter] public bool Disabled { get; set; }

    private List<string> _libraries = new();
    private bool _loading, _open;
    private string _error = string.Empty;
    private string? _loadedForSite;

    private async Task OnTextInput(ChangeEventArgs e)
    {
        Library = e.Value?.ToString() ?? string.Empty;
        await LibraryChanged.InvokeAsync(Library);
    }

    private async Task Browse()
    {
        _error = string.Empty;
        if (string.IsNullOrWhiteSpace(SiteUrl)) { _error = "Select a site first."; return; }

        // Toggle closed if already showing the list for this site.
        if (_open && _loadedForSite == SiteUrl) { _open = false; return; }

        // Reload when the site changed since the last load.
        if (_libraries.Count == 0 || _loadedForSite != SiteUrl)
        {
            _loading = true;
            try
            {
                _libraries = (await LibraryDiscovery.ListLibrariesAsync(Profile, SiteUrl!)).ToList();
                _loadedForSite = SiteUrl;
            }
            catch (Exception ex) { _error = ex.Message; return; }
            finally { _loading = false; }
        }
        _open = true;
    }

    private async Task Pick(string lib)
    {
        Library = lib;
        _open = false;
        await LibraryChanged.InvokeAsync(Library);
    }
}