import { 
  CheckCircle, 
  XCircle, 
  Clock, 
  MessageSquare, 
  RefreshCw, 
  UserPlus, 
  FileText, 
  Paperclip, 
  AlertTriangle, 
  Activity 
} from 'lucide-react';

/**
 * Utility: getPriorityConfig
 * 
 * Purpose: Get display configuration for priority badges
 * 
 * Returns: Object with color classes and label text
 * 
 * Priority levels:
 * - express/urgent: Red background, high visibility
 * - standard: Blue background, normal visibility
 * - default: Gray background, low visibility
 * 
 * @param priority - Priority string from backend
 * @returns Configuration object with Tailwind CSS classes
 */
export const getPriorityConfig = (priority: string) => {
  switch (priority) {
    case 'express':
    case 'urgent':
      return {
        color: 'bg-red-100 text-red-800 border-red-200',
        label: 'urgent priority'
      };
    case 'standard':
      return {
        color: 'bg-blue-100 text-blue-800 border-blue-200',
        label: 'standard priority'
      };
    default:
      return {
        color: 'bg-gray-100 text-gray-800 border-gray-200',
        label: 'normal priority'
      };
  }
};

/**
 * Utility: getStatusConfig
 * 
 * Purpose: Get display configuration for status badges
 * 
 * Returns: Object with color classes and label text
 * 
 * Status types:
 * - pending: Yellow (waiting for action)
 * - in-review: Blue (actively being reviewed)
 * - approved: Green (successfully approved)
 * - rejected: Red (declined)
 * - closed: Gray (finalized and archived)
 * - skipped: Orange (bypassed approver)
 * 
 * @param status - Status string from backend
 * @returns Configuration object with Tailwind CSS classes
 */
export const getStatusConfig = (status: string) => {
  switch (status) {
    case 'pending':
      return {
        color: 'bg-yellow-100 text-yellow-800 border-yellow-200',
        label: 'pending'
      };
    case 'paused':
      return {
        color: 'bg-gray-400 text-gray-100 border-gray-500',
        label: 'paused'
      };
    case 'in-review':
      return {
        color: 'bg-blue-100 text-blue-800 border-blue-200',
        label: 'in-review'
      };
    case 'approved':
      return {
        color: 'bg-green-100 text-green-800 border-green-200',
        label: 'approved'
      };
    case 'rejected':
      return {
        color: 'bg-red-100 text-red-800 border-red-200',
        label: 'rejected'
      };
    case 'closed':
      return {
        color: 'bg-gray-100 text-gray-800 border-gray-300',
        label: 'closed'
      };
    case 'skipped':
      return {
        color: 'bg-orange-100 text-orange-800 border-orange-200',
        label: 'skipped'
      };
    default:
      return {
        color: 'bg-gray-100 text-gray-800 border-gray-200',
        label: status
      };
  }
};

/**
 * Utility: getActionTypeIcon
 * 
 * Purpose: Get appropriate icon for activity timeline entries
 * 
 * Returns: Lucide icon component for the action type
 * 
 * Action types:
 * - approval/approved: Green checkmark
 * - rejection/rejected: Red X
 * - comment: Blue message bubble
 * - status_change/updated: Orange refresh
 * - assignment: Purple user plus
 * - created: Blue file
 * - reminder: Yellow clock
 * - document_added: Indigo paperclip
 * - sla_warning: Amber warning triangle
 * - default: Gray activity pulse
 * 
 * @param type - Activity type from backend
 * @returns JSX icon element with appropriate color
 */
export const getActionTypeIcon = (type: string) => {
  switch (type) {
    case 'approval':
    case 'approved':
      return <CheckCircle className="w-5 h-5 text-green-600" />;
    case 'rejection':
    case 'rejected':
      return <XCircle className="w-5 h-5 text-red-600" />;
    case 'comment':
      return <MessageSquare className="w-5 h-5 text-blue-600" />;
    case 'status_change':
    case 'updated':
      return <RefreshCw className="w-5 h-5 text-orange-600" />;
    case 'assignment':
      return <UserPlus className="w-5 h-5 text-purple-600" />;
    case 'created':
      return <FileText className="w-5 h-5 text-blue-600" />;
    case 'reminder':
      return <Clock className="w-5 h-5 text-yellow-600" />;
    case 'document_added':
      return <Paperclip className="w-5 h-5 text-indigo-600" />;
    case 'sla_warning':
      return <AlertTriangle className="w-5 h-5 text-amber-600" />;
    default:
      return <Activity className="w-5 h-5 text-gray-600" />;
  }
};