using Core.Entities;

namespace Core.Parsers.EventOccurrence;

/// <summary>
/// Resolves event definitions from occurrence name patterns or section context.
/// </summary>
public static class EventDefinitionResolver
{
    /// <summary>
    /// Maps special event name patterns to their EventDefinition instances.
    /// Patterns are checked in order, and the first match wins.
    /// </summary>
    private static readonly Dictionary<string, EventDefinition> SpecialEventPatterns = 
        new(StringComparer.OrdinalIgnoreCase)
    {
        ["Meet the Candidates"] = EventDefinition.MeetTheCandidates,
        ["Chapter Officer Meeting"] = EventDefinition.ChapterOfficerMeeting,
        ["Voting Delegate Meeting"] = EventDefinition.VotingDelegateMeeting,
    };

    /// <summary>
    /// Determines the EventDefinition for an occurrence based on its name pattern or current section context.
    /// </summary>
    /// <param name="occurrenceName">The name of the occurrence.</param>
    /// <param name="currentEventDefinition">The current event definition from section header, if any.</param>
    /// <returns>The resolved EventDefinition, or null if it cannot be determined.</returns>
    public static EventDefinition? Resolve(string occurrenceName, EventDefinition? currentEventDefinition)
    {
        // Check for special event name patterns first (regardless of current section)
        foreach (var (pattern, eventDef) in SpecialEventPatterns)
        {
            if (occurrenceName.Contains(pattern, StringComparison.OrdinalIgnoreCase))
                return eventDef;
        }

        // If we're in a General Schedule/Session section and no pattern matched, use GeneralSchedule
        if (currentEventDefinition == EventDefinition.GeneralSchedule)
            return EventDefinition.GeneralSchedule;

        // If we have a current event definition from section header (e.g., regular events), use it
        return currentEventDefinition;
    }
}