namespace Core.Parsers.EventOccurrence;

/// <summary>
/// Classifies lines to determine if they should be skipped during parsing.
/// </summary>
public static class LineClassifier
{
    /// <summary>
    /// Checks if a line is empty or contains only whitespace.
    /// </summary>
    public static bool IsEmptyLine(string line)
    {
        return string.IsNullOrWhiteSpace(line);
    }

    /// <summary>
    /// Checks if a line is a comment (starts with "#").
    /// </summary>
    public static bool IsCommentLine(string line)
    {
        return EventOccurrenceGrammar.IsCommentLine(line);
    }

    /// <summary>
    /// Determines if a line is a continuation/wrapped line that should be skipped.
    /// These are typically lines that:
    /// - Start with lowercase or special characters (not event names)
    /// - Are parenthetical notes like "(Semifinalists only)"
    /// - Are informational text like "Schedule Posted on..."
    /// </summary>
    public static bool IsContinuationLine(string line)
    {
        var trimmed = line.Trim();
        
        // Skip parenthetical notes
        if (trimmed.StartsWith("(", StringComparison.Ordinal) && trimmed.EndsWith(")", StringComparison.Ordinal))
            return true;
        
        // Skip lines that are clearly continuation text (start with lowercase, common continuation words)
        if (trimmed.Length > 0 && char.IsLower(trimmed[0]))
        {
            // Check if it starts with common continuation words
            var continuationPrefixes = new[] { "be ", "the ", "and ", "or ", "to ", "a ", "an ", "will ", "may ", "can " };
            foreach (var prefix in continuationPrefixes)
            {
                if (trimmed.StartsWith(prefix, StringComparison.OrdinalIgnoreCase))
                    return true;
            }
        }
        
        // Skip informational lines that don't contain dates/times
        if (trimmed.Contains("Schedule Posted", StringComparison.OrdinalIgnoreCase) ||
            trimmed.Contains("Note:", StringComparison.OrdinalIgnoreCase))
            return true;
        
        return false;
    }
}