namespace Musify.Application.Tracks.Responses
{
    /// <summary>Result of a combined tracks listing/search: a page of local catalog tracks
    /// (uploads and previously provisioned YouTube tracks), plus, when a search term was given,
    /// live YouTube Music hits appended after them. Pagination metadata (<see cref="PageNumber"/>,
    /// <see cref="PageSize"/>, <see cref="PageCount"/>, <see cref="TotalItemCount"/>) describes only
    /// the local page — YouTube has no stable total, so its continuation is tracked separately via
    /// <see cref="NextYoutubeContinuationToken"/>.</summary>
    public record TracksSearchResponse(
        IReadOnlyList<TrackSearchItemResponse> Items,
        int PageNumber,
        int PageSize,
        int PageCount,
        int TotalItemCount,
        bool HasPreviousPage,
        bool HasNextLocalPage,
        string? NextYoutubeContinuationToken,
        bool YoutubeUnavailable,
        bool HasNextPage)
    {
        // HasNextPage is a real field (not a computed property) so it shows up as a required member
        // of the generated OpenAPI schema, same as every other field here — a get-only property added
        // outside the primary constructor gets reflected as optional instead, which is never true here.
        public static TracksSearchResponse Create(
            IReadOnlyList<TrackSearchItemResponse> items,
            int pageNumber,
            int pageSize,
            int pageCount,
            int totalItemCount,
            bool hasPreviousPage,
            bool hasNextLocalPage,
            string? nextYoutubeContinuationToken,
            bool youtubeUnavailable) =>
            new(items, pageNumber, pageSize, pageCount, totalItemCount, hasPreviousPage, hasNextLocalPage,
                nextYoutubeContinuationToken, youtubeUnavailable,
                HasNextPage: hasNextLocalPage || !string.IsNullOrEmpty(nextYoutubeContinuationToken));
    }
}