using System.Net;
using System.Runtime.CompilerServices;
using Flurl;
using Flurl.Http;

namespace Piwigo.Client;

public class PiwigoClient : IPiwigoClient
{
    private CookieJar _cookies = new();
    private string _piwigoBaseUri = null!;
    public bool IsLoggedIn { get; private set; }
    public int ChunkSize { get; set; } = 512;
    private IFlurlRequest Request => _piwigoBaseUri.WithCookies(_cookies);

    public async Task LoginAsync(Uri uri, string username, string password)
    {
        if (uri == null)
        {
            throw new ArgumentNullException(nameof(uri));
        }

        if (string.IsNullOrWhiteSpace(username))
        {
            throw new ArgumentException("Value cannot be null or whitespace.", nameof(username));
        }

        if (string.IsNullOrWhiteSpace(password))
        {
            throw new ArgumentException("Value cannot be null or whitespace.", nameof(password));
        }

        if (IsLoggedIn)
        {
            throw new PiwigoException("The client is already logged in. Create a new instance or log out first!");
        }

        _piwigoBaseUri = uri.AppendPathSegment("ws.php").SetQueryParam("format", "json");

        var response = await _piwigoBaseUri.WithCookies(out var cookieJar).PostMultipartAsync(c =>
            c.PiwigoLogin(username, password));

        if (response.StatusCode != (int)HttpStatusCode.OK)
        {
            throw new PiwigoException($"Could not log in to {_piwigoBaseUri} using username {username}");
        }

        _cookies = cookieJar;
        IsLoggedIn = true;
    }

    public async Task Logout()
    {
        EnsureLoggedIn();

        await Request.PostMultipartAsync(c => c.PiwigoLogout());

        IsLoggedIn = false;
        _cookies.Clear();
    }

    private void EnsureLoggedIn([CallerMemberName] string? callerName = null)
    {
        if (!IsLoggedIn)
        {
            throw new InvalidOperationException($"Could not execute {callerName} as the client is not logged in.");
        }
    }
}