@page "/admin/federation"
@using Iceshrimp.Backend.Components.Admin
@using Iceshrimp.Backend.Core.Configuration
@using Iceshrimp.Backend.Core.Database.Tables
@using Iceshrimp.Backend.Core.Extensions
@using Iceshrimp.Backend.Core.Middleware
@using Microsoft.EntityFrameworkCore
@using Microsoft.Extensions.Options
@using static Iceshrimp.Backend.Core.Configuration.Enums;
@using Microsoft.AspNetCore.Components.Forms
@inherits AdminComponentBase
<AdminHead/>
<AdminPageHeader Title="@($"{ModeString} instances")"/>
<table>
    <thead>
    <th>Host</th>
    <th>Imported</th>
    @if (IsBlocklist)
    {
        <th>Reason</th>
    }
    <th>Actions</th>
    </thead>
    <tbody>
    @if (IsBlocklist)
    {
        @foreach (var instance in _blockedInstances)
        {
            <tr>
                @{
                    var host = instance.Host;
                    if (host.StartsWith("xn--"))
                        host = $"{host.FromPunycode()} ({host})";
                }
                <td>@host</td>
                <td>
                    <i>@(instance.IsImported ? "Yes" : "No")</i>
                </td>
                <td>
                    @if (instance.Reason is not null)
                    {
                        @instance.Reason
                    }
                    else
                    {
                        <i>No reason set</i>
                    }
                </td>
                <td>
                    <a class="fake-link" onclick="unblockInstance('@instance.Host', event.target)">Unblock</a>
                </td>
            </tr>
        }
    }
    else
    {
        @foreach (var instance in _allowedInstances)
        {
            <tr>
                @{
                    var host = instance.Host;
                    if (host.StartsWith("xn--"))
                        host = host.FromPunycode() + $"({instance.Host})";
                }
                <td>@host</td>
                <td>
                    <i>@(instance.IsImported ? "Yes" : "No")</i>
                </td>
                <td>
                    <a class="fake-link" onclick="disallowInstance('@instance.Host', event.target)">Remove</a>
                </td>
            </tr>
        }
    }
    </tbody>
</table>

@if (_blockedInstances is [] && _allowedInstances is [])
{
    <p>
        <i>No instances listed.</i>
    </p>
}

@if (Offset is > 0)
{
    <button role="link" data-target="/admin/federation?offset=@(Math.Max(0, Offset.Value - 50))" onclick="navigate(event)">❮ Previous page</button>
}
else
{
    <button disabled>❮ Previous page</button>
}

@if (_blockedInstances.Length == 50 || _allowedInstances.Length == 50)
{
    <button role="link" data-target="/admin/federation?offset=@((Offset ?? 0) + 50)" onclick="navigate(event)">Next page ❯</button>
}
else
{
    <button disabled>Next page ❯</button>
}

<h3>Add @ModeString.ToLowerInvariant() instance</h3>
@if (IsBlocklist)
{
    <EditForm FormName="add-host" Model="Model" OnSubmit="@OnSubmit">
        <label for="host">Host</label>
        <InputText @bind-Value="@Model.Host" id="host" placeholder="example.org" required/>
        <label for="reason">Reason</label>
        <InputText @bind-Value="@Model.Reason" id="reason" placeholder="Bad vibes"/>
        <button type="submit">Submit</button>
    </EditForm>
}
else
{
    <EditForm FormName="add-host" Model="Model" OnSubmit="@OnSubmit">
        <label for="host">Host</label>
        <InputText @bind-Value="@Model.Host" id="host" placeholder="example.org" required/>
        <button type="submit">Submit</button>
    </EditForm>
}

@code {
    [Inject] public required IOptionsSnapshot<Config.SecuritySection> Options { get; set; }

    [SupplyParameterFromQuery] public  int?            Offset { get; set; }
    [SupplyParameterFromForm]  private FederationModel Model  { get; set; } = null!;

    private bool              IsBlocklist => Options.Value.FederationMode == FederationMode.BlockList;
    private string            ModeString  => IsBlocklist ? "Blocked" : "Allowed";
    private BlockedInstance[] _blockedInstances = [];
    private AllowedInstance[] _allowedInstances = [];

    private class FederationModel
    {
        public string? Host   { get; set; }
        public string? Reason { get; set; }

        public void Canonicalize()
        {
            Host   = Host?.Trim().ToPunycodeLower();
            Reason = Reason?.Trim();

            if (Host?.Length == 0)
                Host = null;
            if (Reason?.Length == 0)
                Reason = null;
        }
    }

    protected override void OnParametersSet()
    {
        // ReSharper disable once NullCoalescingConditionIsAlwaysNotNullAccordingToAPIContract
        Model ??= new FederationModel();
    }

    protected override async Task OnGet()
    {
        if (IsBlocklist)
            _blockedInstances = await Database.BlockedInstances.OrderBy(p => p.Host).Skip(Offset ?? 0).Take(50).ToArrayAsync();
        else
            _allowedInstances = await Database.AllowedInstances.OrderBy(p => p.Host).Skip(Offset ?? 0).Take(50).ToArrayAsync();
    }

    private async Task OnSubmit()
    {
        Model.Canonicalize();
        if (Model.Host == null)
            throw GracefulException.BadRequest("Missing host field");

        if (IsBlocklist)
        {
            if (await Database.BlockedInstances.FirstOrDefaultAsync(p => p.Host == Model.Host) is { } instance)
            {
                instance.Reason     = Model.Reason;
                instance.IsImported = false;
            }
            else
            {
                var newInstance = new BlockedInstance
                {
                    Host       = Model.Host,
                    Reason     = Model.Reason,
                    IsImported = false
                };

                Database.Add(newInstance);
            }
        }
        else
        {
            if (!await Database.AllowedInstances.AnyAsync(p => p.Host == Model.Host))
            {
                var newInstance = new AllowedInstance { Host = Model.Host, IsImported = false };
                Database.Add(newInstance);
            }
        }

        await Database.SaveChangesAsync();
        ReloadPage();
    }
}