using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Json;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;
using StellaOps.Cli.Services.Models;

namespace StellaOps.Cli.Services;

/// <summary>
/// HTTP client for Authority console endpoints (CLI-TEN-47-001, CLI-TEN-49-001).
/// </summary>
internal sealed class AuthorityConsoleClient : IAuthorityConsoleClient
{
    private readonly HttpClient _httpClient;
    private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web);

    public AuthorityConsoleClient(HttpClient httpClient)
    {
        _httpClient = httpClient ?? throw new ArgumentNullException(nameof(httpClient));
    }

    public async Task<IReadOnlyList<TenantInfo>> ListTenantsAsync(string tenant, CancellationToken cancellationToken)
    {
        using var request = new HttpRequestMessage(HttpMethod.Get, "console/tenants");

        if (!string.IsNullOrWhiteSpace(tenant))
        {
            request.Headers.Add("X-StellaOps-Tenant", tenant.Trim().ToLowerInvariant());
        }

        using var response = await _httpClient.SendAsync(request, cancellationToken).ConfigureAwait(false);
        response.EnsureSuccessStatusCode();

        var result = await response.Content
            .ReadFromJsonAsync<TenantListResponse>(cancellationToken: cancellationToken)
            .ConfigureAwait(false);

        return result?.Tenants ?? Array.Empty<TenantInfo>();
    }

    public async Task<TokenMintResponse> MintTokenAsync(TokenMintRequest request, CancellationToken cancellationToken)
    {
        ArgumentNullException.ThrowIfNull(request);

        using var httpRequest = new HttpRequestMessage(HttpMethod.Post, "console/token/mint")
        {
            Content = JsonContent.Create(request, options: JsonOptions)
        };

        if (!string.IsNullOrWhiteSpace(request.Tenant))
        {
            httpRequest.Headers.Add("X-StellaOps-Tenant", request.Tenant.Trim().ToLowerInvariant());
        }

        using var response = await _httpClient.SendAsync(httpRequest, cancellationToken).ConfigureAwait(false);
        response.EnsureSuccessStatusCode();

        var result = await response.Content
            .ReadFromJsonAsync<TokenMintResponse>(JsonOptions, cancellationToken)
            .ConfigureAwait(false);

        return result ?? throw new InvalidOperationException("Token mint response was empty.");
    }

    public async Task<TokenDelegateResponse> DelegateTokenAsync(TokenDelegateRequest request, CancellationToken cancellationToken)
    {
        ArgumentNullException.ThrowIfNull(request);

        using var httpRequest = new HttpRequestMessage(HttpMethod.Post, "console/token/delegate")
        {
            Content = JsonContent.Create(request, options: JsonOptions)
        };

        if (!string.IsNullOrWhiteSpace(request.Tenant))
        {
            httpRequest.Headers.Add("X-StellaOps-Tenant", request.Tenant.Trim().ToLowerInvariant());
        }

        using var response = await _httpClient.SendAsync(httpRequest, cancellationToken).ConfigureAwait(false);
        response.EnsureSuccessStatusCode();

        var result = await response.Content
            .ReadFromJsonAsync<TokenDelegateResponse>(JsonOptions, cancellationToken)
            .ConfigureAwait(false);

        return result ?? throw new InvalidOperationException("Token delegation response was empty.");
    }

    public async Task<TokenIntrospectionResponse?> IntrospectTokenAsync(string? tenant, CancellationToken cancellationToken)
    {
        using var httpRequest = new HttpRequestMessage(HttpMethod.Post, "console/token/introspect");

        if (!string.IsNullOrWhiteSpace(tenant))
        {
            httpRequest.Headers.Add("X-StellaOps-Tenant", tenant.Trim().ToLowerInvariant());
        }

        using var response = await _httpClient.SendAsync(httpRequest, cancellationToken).ConfigureAwait(false);

        if (!response.IsSuccessStatusCode)
        {
            return null;
        }

        return await response.Content
            .ReadFromJsonAsync<TokenIntrospectionResponse>(JsonOptions, cancellationToken)
            .ConfigureAwait(false);
    }
}