namespace SeaHaven.Services.Helpers
{
    public static class WorkOrderBoardApptTimeParser
    {
        public static bool TryParse(string? value, out TimeSpan? start, out TimeSpan? end, out string? error)
        {
            start = null;
            end = null;
            error = null;

            if (string.IsNullOrWhiteSpace(value))
                return true;

            var trimmed = value.Trim();
            var parts = trimmed.Split(new[] { '–', '—', '-' })
                .Select(p => p.Trim())
                .Where(p => !string.IsNullOrEmpty(p))
                .ToArray();

            if (parts.Length == 1)
            {
                if (!TimeSpan.TryParse(parts[0], out var single))
                {
                    error = "Invalid appointment time format.";
                    return false;
                }

                start = single;
                return true;
            }

            if (parts.Length == 2)
            {
                if (!TimeSpan.TryParse(parts[0], out var startTime) || !TimeSpan.TryParse(parts[1], out var endTime))
                {
                    error = "Invalid appointment time range format.";
                    return false;
                }

                start = startTime;
                end = endTime;
                return true;
            }

            error = "Invalid appointment time format.";
            return false;
        }

        public static DateTime? CombineDateAndTime(DateTime? date, TimeSpan? time)
        {
            if (!date.HasValue || !time.HasValue)
                return date;

            return date.Value.Date.Add(time.Value);
        }

        public static DateTime? ToScheduledInstant(DateTime? date, TimeSpan? time)
            => time.HasValue ? CombineDateAndTime(date, time) : null;
    }
}