using System.Collections.ObjectModel;
using OF_DL.Models.Config;

namespace OF_DL.Gui.ViewModels;

public sealed class ConfigCategoryViewModel : ViewModelBase
{
    public ConfigCategoryViewModel(string categoryName, IEnumerable<ConfigFieldViewModel> fields)
    {
        CategoryName = categoryName;
        List<ConfigFieldViewModel> fieldList = fields.ToList();

        DownloadOnlySpecificDatesField = fieldList.FirstOrDefault(field =>
            string.Equals(field.PropertyName, nameof(Config.DownloadOnlySpecificDates), StringComparison.Ordinal));
        DownloadDateSelectionField = fieldList.FirstOrDefault(field =>
            string.Equals(field.PropertyName, nameof(Config.DownloadDateSelection), StringComparison.Ordinal));
        CustomDateField = fieldList.FirstOrDefault(field =>
            string.Equals(field.PropertyName, nameof(Config.CustomDate), StringComparison.Ordinal));

        IEnumerable<ConfigFieldViewModel> visibleFields = IsDownloadBehavior
            ? fieldList.Where(field => field.PropertyName is not nameof(Config.DownloadOnlySpecificDates)
                and not nameof(Config.DownloadDateSelection)
                and not nameof(Config.CustomDate))
            : fieldList;

        foreach (ConfigFieldViewModel field in visibleFields)
        {
            Fields.Add(field);
        }
    }

    public string CategoryName { get; }

    public bool IsDownloadBehavior =>
        string.Equals(CategoryName, "Download Behavior", StringComparison.Ordinal);

    public ConfigFieldViewModel? DownloadOnlySpecificDatesField { get; }

    public ConfigFieldViewModel? DownloadDateSelectionField { get; }

    public ConfigFieldViewModel? CustomDateField { get; }

    public bool HasSpecificDateFilterFields =>
        DownloadOnlySpecificDatesField != null &&
        DownloadDateSelectionField != null &&
        CustomDateField != null;

    public string SpecificDateFilterHelpText
    {
        get
        {
            List<string> parts = [];
            if (!string.IsNullOrWhiteSpace(DownloadOnlySpecificDatesField?.HelpText))
            {
                parts.Add(DownloadOnlySpecificDatesField.HelpText);
            }

            if (!string.IsNullOrWhiteSpace(DownloadDateSelectionField?.HelpText))
            {
                parts.Add(DownloadDateSelectionField.HelpText);
            }

            if (!string.IsNullOrWhiteSpace(CustomDateField?.HelpText))
            {
                parts.Add(CustomDateField.HelpText);
            }

            return string.Join(" ", parts.Distinct(StringComparer.Ordinal));
        }
    }

    public bool HasSpecificDateFilterHelpText => !string.IsNullOrWhiteSpace(SpecificDateFilterHelpText);

    public ObservableCollection<ConfigFieldViewModel> Fields { get; } = [];
}