using System.Collections.ObjectModel;
using Microsoft.Extensions.Logging;
using Piwigo.Client.Contract;

namespace Piwigo.Client;

internal static class DictionaryExtensions
{
    public static IDictionary<string, string> AddIfValueNotNull(this IDictionary<string, string> dictionary, string key, string? value)
    {
        if (dictionary == null)
        {
            throw new ArgumentNullException(nameof(dictionary));
        }

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

        if (value is not null)
        {
            dictionary.Add(key, value);
        }

        return dictionary;
    }
}

public class CategoryApi : ICategoryApi
{
    private readonly IPiwigoContext _context;
    private readonly ILogger<CategoryApi> _logger;

    public CategoryApi(IPiwigoContext context, ILogger<CategoryApi> logger)
    {
        _context = context ?? throw new ArgumentNullException(nameof(context));
        _logger = logger ?? throw new ArgumentNullException(nameof(logger));
    }

    public async Task<int> AddAsync(string name, int? parentId = null, string? comment = null, bool? visible = null, CategoryStatus? status = null, bool? commentable = null,
        CategoryPosition? position = null)
    {
        var statusValue = status switch
        {
            CategoryStatus.Public => "public",
            CategoryStatus.Private => "private",
            null => null,
            _ => throw new ArgumentOutOfRangeException(nameof(status), status, null)
        };

        var positionValue = position switch
        {
            CategoryPosition.First => "first",
            CategoryPosition.Last => "last",
            null => null,
            _ => throw new ArgumentOutOfRangeException(nameof(position), position, null)
        };

        var formParams = new Dictionary<string, string> { { "name", name } };
        formParams.AddIfValueNotNull("parent", parentId?.ToString()).AddIfValueNotNull("comment", comment).AddIfValueNotNull("visible", visible?.ToString())
            .AddIfValueNotNull("status", statusValue).AddIfValueNotNull("commentable", visible?.ToString()).AddIfValueNotNull("position", positionValue);

        var response = await _context.PostAsync<PiwigoResponse<AlbumAdded>>(_logger, "pwg.categories.add", formParams);
        if (!response.Result.Id.HasValue)
        {
            throw new PiwigoException($"Could not create album {name}: {response.Result.Info}");
        }

        return response.Result.Id.Value;
    }

    public async Task<IReadOnlyCollection<PiwigoCategory>> GetAllAsync()
    {
        _logger.LogInformation("Getting all existing categories from server");
        var formParams = new Dictionary<string, string> { { "recursive", "true" } };
        var response = await _context.PostAsync<PiwigoResponse<PiwigoCategoryList>>(_logger, "pwg.categories.getList", formParams);
        return new ReadOnlyCollection<PiwigoCategory>(response.Result.Categories);
    }
}