/**
 * Domain Entity: EngagementEvent
 * 
 * Represents user interactions beyond page views.
 * Tracks clicks, downloads, sign-ups, and other engagement actions.
 */

export type EngagementAction = 
  | 'click_sponsor_logo'
  | 'click_sponsor_url'
  | 'download_livery_pack'
  | 'join_league'
  | 'register_race'
  | 'view_standings'
  | 'view_schedule'
  | 'share_social'
  | 'contact_sponsor';

export type EngagementEntityType = 'league' | 'driver' | 'team' | 'race' | 'sponsor' | 'sponsorship';

export interface EngagementEventProps {
  id: string;
  action: EngagementAction;
  entityType: EngagementEntityType;
  entityId: string;
  actorId?: string;
  actorType: 'anonymous' | 'driver' | 'sponsor';
  sessionId: string;
  metadata?: Record<string, string | number | boolean>;
  timestamp: Date;
}

export class EngagementEvent {
  readonly id: string;
  readonly action: EngagementAction;
  readonly entityType: EngagementEntityType;
  readonly entityId: string;
  readonly actorId?: string;
  readonly actorType: 'anonymous' | 'driver' | 'sponsor';
  readonly sessionId: string;
  readonly metadata?: Record<string, string | number | boolean>;
  readonly timestamp: Date;

  private constructor(props: EngagementEventProps) {
    this.id = props.id;
    this.action = props.action;
    this.entityType = props.entityType;
    this.entityId = props.entityId;
    this.actorId = props.actorId;
    this.actorType = props.actorType;
    this.sessionId = props.sessionId;
    this.metadata = props.metadata;
    this.timestamp = props.timestamp;
  }

  static create(props: Omit<EngagementEventProps, 'timestamp'> & { timestamp?: Date }): EngagementEvent {
    this.validate(props);

    return new EngagementEvent({
      ...props,
      timestamp: props.timestamp ?? new Date(),
    });
  }

  private static validate(props: Omit<EngagementEventProps, 'timestamp'>): void {
    if (!props.id || props.id.trim().length === 0) {
      throw new Error('EngagementEvent ID is required');
    }

    if (!props.action) {
      throw new Error('EngagementEvent action is required');
    }

    if (!props.entityType) {
      throw new Error('EngagementEvent entityType is required');
    }

    if (!props.entityId || props.entityId.trim().length === 0) {
      throw new Error('EngagementEvent entityId is required');
    }

    if (!props.sessionId || props.sessionId.trim().length === 0) {
      throw new Error('EngagementEvent sessionId is required');
    }
  }

  /**
   * Check if this is a sponsor-related engagement
   */
  isSponsorEngagement(): boolean {
    return this.action.startsWith('click_sponsor') || 
           this.action === 'contact_sponsor' ||
           this.entityType === 'sponsor' ||
           this.entityType === 'sponsorship';
  }

  /**
   * Check if this is a conversion event (high-value action)
   */
  isConversionEvent(): boolean {
    return ['join_league', 'register_race', 'click_sponsor_url', 'contact_sponsor'].includes(this.action);
  }

  /**
   * Get engagement weight for analytics calculations
   */
  getEngagementWeight(): number {
    const weights: Record<EngagementAction, number> = {
      'click_sponsor_logo': 2,
      'click_sponsor_url': 5,
      'download_livery_pack': 3,
      'join_league': 10,
      'register_race': 8,
      'view_standings': 1,
      'view_schedule': 1,
      'share_social': 4,
      'contact_sponsor': 15,
    };
    return weights[this.action] || 1;
  }
}