@page "/voiceworks"
@using JSMR.Application.Common.Search
@using JSMR.Application.VoiceWorks.Queries.Search
@using JSMR.UI.Blazor.Components
@using JSMR.UI.Blazor.Filters
@using JSMR.UI.Blazor.Services
@using Microsoft.AspNetCore.WebUtilities
@inject VoiceWorksClient Client
@inject IJSRuntime JS
@inject NavigationManager NavigationManager
@implements IAsyncDisposable;

<PageTitle>Voice Works</PageTitle>

<h3>Voice Works</h3>

<VoiceWorkFilters Value="@FilterState" ValueChanged="OnFilterStateChanged" />

<JProductCollection Products="searchResults?.Items"></JProductCollection>

@if (searchResults is not null)
{
    <JPagination PageNumber="@FilterState.PageNumber"
                 PageNumberChanged="@(pageNumber => OnFilterStateChanged(FilterState with { PageNumber = pageNumber }))"
                 PageSize="@FilterState.PageSize"
                 PageSizeChanged="@(pageSize => OnFilterStateChanged(FilterState with { PageSize = pageSize, PageNumber = 1 }))"
                 @bind-TotalItems="searchResults.TotalItems" />
}

@code {
    private bool _isAlive = true;
    private CancellationTokenSource _cts = new();

    VoiceWorkFilterState FilterState = new();
    SearchResult<VoiceWorkSearchResult>? searchResults;

    protected override async Task OnInitializedAsync()
    {
        NavigationManager.LocationChanged += OnLocationChanged;

        FilterState = VoiceWorkFilterState.FromQuery(new Uri(NavigationManager.Uri).Query);
        await RunSearchAsync();
    }

    private async void OnLocationChanged(object? sender, LocationChangedEventArgs e)
    {
        if (!_isAlive)
            return;

        if (!IsThisPage(e.Location))
            return;

        // Parse query from the new URL and update state if it actually changed.
        string query = NavigationManager.ToAbsoluteUri(e.Location).Query;
        VoiceWorkFilterState next = VoiceWorkFilterState.FromQuery(query);

        if (next != FilterState)
        {
            FilterState = next;
            await RunSearchAsync();
            await InvokeAsync(StateHasChanged);
        }
    }

    private bool IsThisPage(string absoluteUri)
    {
        string baseRelativePath = NavigationManager.ToBaseRelativePath(absoluteUri);

        return baseRelativePath.StartsWith("voiceworks", StringComparison.OrdinalIgnoreCase);
    }

    async Task OnFilterStateChanged(VoiceWorkFilterState next)
    {
        if (next == FilterState)
            return;

        UpdateUrl(next, false);
    }

    void UpdateUrl(VoiceWorkFilterState next, bool replace)
    {
        string basePath = new Uri(NavigationManager.Uri).GetLeftPart(UriPartial.Path);
        string uri = QueryHelpers.AddQueryString(basePath, next.ToQuery());

        NavigationManager.NavigateTo(uri, replace: replace);
    }

    async Task RunSearchAsync()
    {
        await JS.InvokeVoidAsync("pageHelpers.scrollToTop");

        try
        {
            _cts.Cancel();
            _cts = new();

            SearchVoiceWorksResponse? response = await Client.SearchAsync(FilterState.ToSearchRequest(), _cts.Token);
            searchResults = response?.Results;
        }
        catch (OperationCanceledException)
        {
            
        }
    }

    public async ValueTask DisposeAsync()
    {
        _isAlive = false;
        NavigationManager.LocationChanged -= OnLocationChanged;
        _cts.Cancel();
        _cts.Dispose();
        await Task.CompletedTask;
    }
}