/**
 * Moderation Queue Sorting Utilities
 * 
 * Provides sorting functions and utilities for moderation queue items.
 */

import type { ModerationItem, SortField, SortDirection, SortConfig } from '@/types/moderation';

/**
 * Sort moderation items based on configuration
 * 
 * @param items - Array of moderation items to sort
 * @param config - Sort configuration
 * @returns Sorted array of items
 */
export function sortModerationItems(
  items: ModerationItem[],
  config: SortConfig
): ModerationItem[] {
  const { field, direction } = config;
  
  return [...items].sort((a, b) => {
    let comparison = 0;
    
    switch (field) {
      case 'created_at':
        comparison = new Date(a.created_at).getTime() - new Date(b.created_at).getTime();
        break;
        
      case 'username':
        const usernameA = a.user_profile?.username || a.user_profile?.display_name || '';
        const usernameB = b.user_profile?.username || b.user_profile?.display_name || '';
        comparison = usernameA.localeCompare(usernameB);
        break;
        
      case 'submission_type':
        comparison = (a.submission_type || '').localeCompare(b.submission_type || '');
        break;
        
      case 'status':
        comparison = a.status.localeCompare(b.status);
        break;
        
      case 'escalated':
        const escalatedA = a.escalated ? 1 : 0;
        const escalatedB = b.escalated ? 1 : 0;
        comparison = escalatedB - escalatedA; // Escalated items first
        break;
        
      default:
        comparison = 0;
    }
    
    return direction === 'asc' ? comparison : -comparison;
  });
}

/**
 * Get default sort configuration
 * 
 * @returns Default sort config
 */
export function getDefaultSortConfig(): SortConfig {
  return {
    field: 'created_at',
    direction: 'asc',
  };
}

/**
 * Load sort configuration from localStorage
 * 
 * @param key - localStorage key
 * @returns Saved sort config or default
 */
export function loadSortConfig(key: string = 'moderationQueue_sortConfig'): SortConfig {
  try {
    const saved = localStorage.getItem(key);
    if (saved) {
      return JSON.parse(saved);
    }
  } catch (error) {
    console.error('Failed to load sort config:', error);
  }
  
  return getDefaultSortConfig();
}

/**
 * Save sort configuration to localStorage
 * 
 * @param config - Sort configuration to save
 * @param key - localStorage key
 */
export function saveSortConfig(
  config: SortConfig,
  key: string = 'moderationQueue_sortConfig'
): void {
  try {
    localStorage.setItem(key, JSON.stringify(config));
  } catch (error) {
    console.error('Failed to save sort config:', error);
  }
}

/**
 * Toggle sort direction
 * 
 * @param currentDirection - Current sort direction
 * @returns Toggled direction
 */
export function toggleSortDirection(currentDirection: SortDirection): SortDirection {
  return currentDirection === 'asc' ? 'desc' : 'asc';
}

/**
 * Get human-readable label for sort field
 * 
 * @param field - Sort field
 * @returns Human-readable label
 */
export function getSortFieldLabel(field: SortField): string {
  switch (field) {
    case 'created_at':
      return 'Date Created';
    case 'username':
      return 'Submitter';
    case 'submission_type':
      return 'Type';
    case 'status':
      return 'Status';
    case 'escalated':
      return 'Escalated';
    default:
      return field;
  }
}

/**
 * Check if sort config is default
 * 
 * @param config - Sort configuration to check
 * @returns True if config matches default
 */
export function isDefaultSortConfig(config: SortConfig): boolean {
  const defaultConfig = getDefaultSortConfig();
  return (
    config.field === defaultConfig.field &&
    config.direction === defaultConfig.direction
  );
}