using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Sozsoft.Mcp.Entities;
using Sozsoft.Platform;
using Volo.Abp.Domain.Repositories;
using Volo.Abp.Domain.Services;
using Volo.Abp.MultiTenancy;

namespace Sozsoft.Mcp.Services;

/// <summary>
/// Istegin kiracisina dusen etkin sunucu kaydini cozer.
/// </summary>
public interface IMcpServerConfigProvider
{
    /// <summary>Etkin kayit; kiraciya acik aktif bir kayit yoksa null.</summary>
    Task<McpServer?> GetEffectiveServerAsync();

    /// <summary>Coklu deger tasiyan kolonu (kiraci/arac listesi) ogelerine ayirir.</summary>
    IReadOnlyList<string> SplitMultiValue(string? value);
}

public class McpServerConfigProvider(
    IRepository<McpServer, Guid> serverRepository,
    ICurrentTenant currentTenant)
    : DomainService, IMcpServerConfigProvider
{
    public async Task<McpServer?> GetEffectiveServerAsync()
    {
        var tenantName = currentTenant.Name;

        // Sunucu tanimlari host kapsaminda yasar; kiraci baglamindaki istek de ayni tabloyu
        // okur, hangi kiracilara acik oldugu Tenants kolonunda durur.
        List<McpServer> servers;
        using (currentTenant.Change(null))
        {
            var query = await serverRepository.GetQueryableAsync();
            servers = [.. query.Where(server => server.IsActive).OrderBy(server => server.Name)];
        }

        return servers.Find(server => IsAvailableForTenant(server.Tenants, tenantName));
    }

    public IReadOnlyList<string> SplitMultiValue(string? value)
        => string.IsNullOrWhiteSpace(value)
            ? []
            : [.. value.Split(
                PlatformConsts.MultiValueDelimiter,
                StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)];

    /// <summary>
    /// Kaydin kiraci listesi bos ise tum kiracilara aciktir; doluysa kiraci adi listede
    /// gecmelidir (AiBot ekraniyla ayni sozlesme).
    /// </summary>
    private bool IsAvailableForTenant(string? tenants, string? tenantName)
    {
        var allowed = SplitMultiValue(tenants);
        if (allowed.Count == 0)
        {
            return true;
        }

        return tenantName is not null
            && allowed.Any(name => string.Equals(name, tenantName, StringComparison.OrdinalIgnoreCase));
    }
}